L’importanza della normativa asismica e del béton armé nella ricostruzione delle città dello stretto di Messina
10.6092/issn.1973-9494/7172
Attraverso l’esempio di Reggio Calabria e Messina, completamente distrutte dal terremoto del 28 dicembre 1908, ci si interroga sull’importanza del ruolo della normativa asismica nella ridefinizione urbanistica delle due città dello Stretto, nonché sulla realtà nazionale di inizio secolo volta ad intervenire sulle conseguenze dei terremoti ed a prevenirne gli effetti disastrosi attraverso l’uso di materiali assolutamente innovativi per l’epoca, quali il cemento armato. Giustamente considerate primo esempio di città antisismiche in Italia, Reggio Calabria e Messina, agli inizi del XX secolo, diventano contro la loro volontà un banco di prova non solo per una nuova tecnica costruttiva ma anche per una nuova idea di città che, nella ricostruzione ex novo di ciò che è stato distrutto dal terremoto, intende riadattare le teorie urbanistiche di fine ‘800 alle esigenze architettoniche ed urbane provenienti dalla normativa antisismica emanata in seguito al terribile evento.
application/pdf
1973-9494
7172
en
Mariangela Licordari
Conservation Science in Cultural Heritage
earthquake 2016
The Importance of Seismic Legislation and Reinforced Concrete in the Reconstruction of the Cities of the Strait of Messina
Text.Serial.Journal
https://conservation-science.unibo.it/
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Articles
2017-07-24
2017-07-17
2017-07-24
2017-09-04
237-276
CSCH
Mariangela Licordari
2016
10.6092/issn.1973-9494/7172
237
Université Paris 1 Panthéon-Sorbonne
1973-9494
earthquake 2016
en
276
Zucconi, G. (1989). La città contesa. Dagli ingegneri sanitari agli urbanisti (1885 – 1942). Milano: Jaca Book.
The Importance of Seismic Legislation and Reinforced Concrete in the Reconstruction of the Cities of the Strait of Messina
https://conservation-science.unibo.it/article/download/7172/6903
16
T    HE IMPORTANCE OF SEISMIC LEGISLATION AND
     REINFORCED CONCRETE IN THE RECONSTRUCTION
     OF THE CITIES OF THE STRAIT OF MESSINA

   Mariangela Licordari*9
   Ecole Doctorale 441
   Université Paris 1 Panthéon-Sorbonne, France
   IHA - Universidade Nova de Lisboa FCSH-UNL, Portugal


  Keywords: reinforced concrete, earthquake 1908, aseismic legislation, earthquake
2016


   1. Introduction

    In light of the relationship between seismic legislation, the introduction of new con-
struction techniques and urban planning, the reconstruction of the cities of Reggio
Calabria and Messina after the disastrous earthquake of 1908 can undoubtedly be
considered an interesting field of analysis and study. Immediately after the earthquake,
in fact, many questions arose regarding aseismic legislation and the role that it should
have played in the reconstruction of the two cities of the Strait. [1]
    After the first phase of emergency assistance which, both in Reggio and in Messina,
coincided with the construction of barracks in debris-free areas on the edge of the
old town, the academic community then concentrated on the lines to be followed in
preparing the regulatory planning schemes for the two cities. Two important questions,




                                                                                                   CONSERVATION SCIENCE IN CULTURAL HERITAGE
moreover, needed an answer: on the one hand, the need to determine the most suit-
able sites for rebuilding the city; and, on the other hand, the need to specify the most
appropriate building techniques to prevent any collapse in the event of future earth-
quakes. The necessity of providing immediate answers to the problem of reconstruc-
tion in the areas affected by the earthquake of 1908 represented a decisive factor in
the development of a specific field of engineering: anti-seismic engineering. [2]
    Following the earthquake, the anti-seismic framework developed in those years
successfully established itself throughout the national territory, deeply influencing the
way reinforced concrete was used in Italy. The rapid spread of the material, already
employed in many building types and infrastructures, soon highlighted the need for a
more specific national legislation. A fundamental role in its preparation was assumed
by the Associazione italiana per gli studi sui materiali da costruzione, a centre for
the study of construction materials of the Ministry of Public Works. The drafting of
these regulations determined that each construction in reinforced concrete, had to be
built according to an executive project with static calculations signed by an engineer.
Provisions were made also regarding the quality of the materials and the executive
procedures of the works. For example, strict rules were imposed on the packaging of
mixtures, on the formworks for pouring the concrete into and on the time needed for


* Corresponding author: mariangela.licordari@gmail.com


                                                                                             237
                                                                                                                    dismantling; it also indicated that no work in reinforced concrete could be used before
                                                                                                                    it was properly tested. [1]
                                                                                                                        The planning schemes of the two cities of the Strait were approved in 1909, a few
                                                                                                                    months after the earthquake, to highlight the symbolic rebirth of the cities. To fully un-
M. Licordari - The importance of seismic legislation and reinforced concrete in the reconstruction of the cities




                                                                                                                    derstand the social and cultural conditions that influenced the realization of these plan-
                                                                                                                    ning schemes, special attention should be given to the impact that this natural event
                                                                                                                    caused in the field of scientific research. The extent of the destruction caused by the
                                                                                                                    earthquake started a fierce debate on the most appropriate technology to be adopted
                                                                                                                    for building in areas prone to seismic risk in such a way that the theme “Construct-
                                                                                                                    ing in seismic areas” was the main subject of the “XII Congress of Italian Engineers
                                                                                                                    and Architects”, held in Florence in 1909. Among the various proposals made in this
                                                                                                                    congress, it is important to remember those designed by the “Garden City Movement”,
                                                                                                                    which pointed out as the most suitable solutions: low-density construction, develop-
                                                                                                                    ment in extension of inhabited areas and use of advanced technologies, such as re-
                                                                                                                    inforced concrete and composite structures. The predominant concept was that the
                                                                                                                    new buildings would be a maximum of two floors, with roofing and ceilings that were
                                                                                                                    uniform and light and had massive foundations.1 [2, 3]
                                                                                                                        As a result, reconstruction methods used in both cities were strongly affected by
                                                                                                                    the highly restrictive anti-seismic legislation and strict building code that were adopted.
                                                                                                                    The planning schemes for the cities of Reggio Calabria and Messina, respectively
                                                                                                                    the “Piano De Nava” and “Piano Borzì”, must be re-read keeping in mind two basic
                                                                                                                    principles: on the one hand, maintenance of the safety principles guaranteed by the
                                                                                                                    technical standards for seismic design and, on the other, consideration of the nine-
                                                                                                                    teenth century theories on health and hygiene that strongly conditioned the drafting of
                                                                                                                    these plans. Thus, for example, the elimination of unhealthy urban areas was achieved
                                                                                                                    through the creation of two “new” cities, which extended lengthways and were divided
                                                                                                                    into regular blocks based on a reticular road system, where a decisive role was played
                                                                                                                    by the influence that the technical rules had in defining their “shape”. In fact, the use
                                                                                                                    of reinforced concrete and a specific relationship between building height and road
                                                                                                                    width, determined their “shape”, which still exists today and has allowed these cities to
                                                                                                                    become “newer and more autonomous” than the pre-existing ones. [4]


                                                                                                                       2. Seismic legislation: preventive methods in the urban planning of the two
                                                                                                                          cities of the Strait

                                                                                                                        A few months after the disaster, the problem of reconstructing the areas destroyed
                                                                                                                    by the earthquake was dealt with even greater conviction by special committees whose
                                                                                                                    preliminary work, involving technical and scientific knowledge, became important start-
                                                                                                                    ing points for the elaboration of the new seismic legislation to be adopted in the areas
                                                                                                                    affected by the earthquake. In particular, the study conducted by the “Regio Istituto di
                                                                                                                    Incoraggiamento di Napoli” and prepared in 1909 by a special commission of experts,
                                                                                                                    entitled Contributo alla ricerca delle norme edilizie per le regioni sismiche, had the task
                                                                                                                    of taking stock of the situation on earthquake standards up to that moment in Italy and
                                                                                                                    indicating the main studies published on the subject.2 [5]
                                                                                                                        On the 18th April 1909, the seismic legislation, adopted in the reconstruction of the
                                                                                                                    areas of the Strait was finally approved through the enactment of Royal Decree no.
                                                                                                                    193 (Norme tecniche ed igieniche obbligatorie per le riparazioni, ricostruzioni e nuove


                                                                                                              238
costruzioni degli edifici pubblici e privati nei comuni colpiti dal terremoto del 28 dicem-
bre 1908 o da altri anteriori). The elaboration of this Royal Decree was also the result
of a commission composed of two subcommittees, one of geologists and the other of
engineers. Operating on two different levels, the task for the geologists was to identify
suitable sites for the reconstruction of the two cities, while that of the engineers was to
establish the building criteria to be adopted for the reconstruction, which would then
become legislation.3 [5]
   The Royal Decree, thus, firstly reaffirmed the importance of choosing the right loca-
tion for the new cities, taking up a concept already presented in Royal Decree no. 511
of 16th September 1906 (issued as a result of the 1905 earthquake that had hit the
same areas of the Strait). In Art.1 it states how different seismic, technical and hygiene
aspects, including those relating to the orientation of the buildings had to be taken
into account in the rebuilding of the cities. Article 1 in the Decree of 1909, also clearly
declares it is forbidden to build on land that is marshy, rugged or subject to landslides
or on a steep slope unless it is solid rock, thus renewing the need for a careful choice
of where to build. [6]
   As regards aspects of building design and construction systems to be adopted in
the erection of new buildings, individual solutions were not specified. In accordance
with Art. 7 of the regulations, it was however specified that they had to be built using a
framework made of wood, iron and reinforced concrete able to resist stress from com-
pression, traction and cutting. The regulations included some characteristic structural
types from local tradition, like houses in masonry and the “casa baraccata”, which
was made of stone with an internal structure in wood, whereas it did not consider it
appropriate to employ iron and concrete frames when there was a lack of materials or
their transportation was very expensive. The building types indicated therefore, were in
ordinary masonry; those with a frame composed of a skeleton of vertical and horizontal
elements made of wood, iron or reinforced concrete able to withstand different kinds
of stress; and those that were encaged, constituted by houses in masonry reinforced




                                                                                                      CONSERVATION SCIENCE IN CULTURAL HERITAGE
with iron struts. [5, 6]
   However, it was this legislation that actually promoted the spread of reinforced
concrete in the reconstruction of the two cities. In fact, the provision that limited the
height of masonry buildings to one floor made it less competitive and favored those
in reinforced concrete and reinforced masonry, which instead, gave the opportunity
to build two-storey constructions. Seismic legislation, therefore, became an important
starting point for defining the dimensional and volumetric data of the new buildings.
(Figure 1)
   In order to reduce possible oscillations, the height of the reinforced concrete build-
ings was limited to 10 meters, increased to 16 meters only in some exceptionally justi-
fied cases “[…] for reasons of public utility or services, or artistic interest or industrial
uses […]”.4 Vaults were prohibited as in many previous regulations, except for those
in basements5, and the use of suspended stairs or those borne by arches or masonry
vaults6. All projecting or cantilevered constructions were prohibited, except for balco-
nies, cornices and the overhangs of roofs for which the maximum protuberance was
fixed at 40 - 60 cm.7 In Art. 20, an indication was given of the possibility of replacing
ordinary roofs, either wholly or in part, flat terraces on a level with the eaves, provided
the material used for covering did not exceed 50 kg per m2. This legislation became
fundamental in several aspects of town planning, as it established a special relation-
ship between building height and road width. Specifically, the minimum width of the


                                                                                                239
                                                                                                                    streets was fixed at 10 meters, reduced to 8 in municipalities with fewer than 5,000
                                                                                                                    inhabitants, following the favorable opinion of the Civil Engineering Department, and 6
                                                                                                                    meters if there were buildings only on one side of the road.8 [6]
M. Licordari - The importance of seismic legislation and reinforced concrete in the reconstruction of the cities




                                                                                                                    Figure 1. Reggio Calabria, Isolato n. 24, Libretto delle misure, 1929. (Archivio Storico Comunale
                                                                                                                    di RC – Fondo Ente Edilizio, 10. 7. 2, B 25).

                                                                                                                        It is easy to understand then how these rules determined a type of homogeneity in
                                                                                                                    the urban layout and architecture of the two cities of the Strait in such a way that they
                                                                                                                    were recognized as the very first examples of earthquake-resistant cities in Italy. It also
                                                                                                                    meant that the engineers called to delineate the two plans, De Nava for the city of Reg-
                                                                                                                    gio Calabria and Borzì for Messina, were severely limited in their design.
                                                                                                                        It is evident that these earthquake standards played an important role, both in di-
                                                                                                                    recting the designers’ choices and in helping to establish, in practical terms, the territo-
                                                                                                                    rial dimension, morphology and urban space configuration defined by the proportions
                                                                                                                    between the “wide straight” streets and the reduced height of the buildings. 9 [7, 8]
                                                                                                                    (Figures 2-3).


                                                                                                              240
Figure 2. Luigi Borzì, Piano regolatore della città di Messina, 1910, color print on paper. (Archivio
di Stato di Me – Fondo Prefettura, B 81).




                                                                                                              CONSERVATION SCIENCE IN CULTURAL HERITAGE
Figure 3. P. De Nava, Piano regolatore della città di Reggio Calabria, 1914, India ink and pastels
on paper. (Archivio di Stato di RC – Archivio Foti, n. 10)



    The image of Reggio and Messina after the earthquake, today unfortunately altered
by constant substitutions and elevations, was that of two cities crossed by wide straight
roads with open spaces, whose width and spaciousness was in effect enhanced by the
uniformly low height of the blocks. Within this new spatial concept, the block became
the main constituent element of the urban structure10. In fact, according to the provi-
sions given in the “building regulations” of the two cities, almost all blocks: were to
have the same dimension and quadrangular shape, repeatable ad infinitum; they also
had to coincide with the lots demarcated by the streets; they had to maintain a height
of 10 meters and could not have overhangs or protruberances. The result of these
stringent requirements determined an urban structure without hierarchies, where each
block was an independent element, in other words, an element devoid of functional
and architectural dialogue with the urban context, capable of generating a uniform
periphery that could go in all directions. 11 (Figure 4) [7, 9]


                                                                                                        241
M. Licordari - The importance of seismic legislation and reinforced concrete in the reconstruction of the cities




                                                                                                                    Figure 4. Reggio Calabria, isolato n. 24, pianta del piano terreno, 1929, India ink on paper.
                                                                                                                    (Archivio Storico Comunale di RC – Fondo Ente Edilizio, 10. 7. 2, B 25).

                                                                                                                        To be fair however, it should be remembered that, in the planimetric definition of
                                                                                                                    the two cities, special attention was paid to the urban tradition of the late nineteenth
                                                                                                                    century, with the classic morphological division in blocks forming a chessboard pattern
                                                                                                                    and reflecting the culture of health and hygiene which almost certainly belonged to
                                                                                                                    Pietro De Nava and Luigi Borzì. The themes of spaciousness, sunlight and ventilation,
                                                                                                                    obtained through a rational and schematic structure of the roads, here became the
                                                                                                                    cornerstones for the new idea of the city. The elimination of unhealthy, disorderly and
                                                                                                                    overcrowded areas was embodied in a city divided into regular blocks separated by a
                                                                                                                    reticular system of roads.12 [3]
                                                                                                                       As in the urban mesh of many redesigned cities in the second half of the nine-
                                                                                                                    teenth century, such as Cesare Beruto’s Milan, reorganized with the master plan
                                                                                                                    developed between 1883 and 1884, here too, the block became the main matrix of
                                                                                                                    city building. It was capable of determining greater control of the areas to be built,
                                                                                                                    through the realization of built environments defined in negative (compared to the
                                                                                                                    ‘positive’ of public spaces, such as squares or green areas) and constituted by eve-
                                                                                                                    rything that was between the roads. [10-12] In the case of the two cities of the Strait,
                                                                                                                    however, the new urban grid, with its alternating solids and voids, was tightly bound
                                                                                                                    to the technical anti-seismic standards, resulting in a form of urbis that was really
                                                                                                                    original for the time.


                                                                                                              242
   Although the urban spaces may have been seen as monotonous, it seems that,
in Reggio Calabria and Messina, a very simple ‘open’ cultural model was applied,
such as that described above, which created the conditions for a very distinctive urban
morphology. Paradoxically, therefore, with their extreme simplicity, the technical rules
of De Nava and Borzì’s urban development plan, together with the criteria for its imple-
mentation gave these cities uniform characteristics in their volumes, in the relationship
between the buildings, between the solid and the void, establishing for the time an
entirely original spatial image.13 [7, 13]
   That said, to have a complete idea of their reconstruction, in my opinion, another
question that was mentioned at the beginning of my discussion should be considered,
namely, which construction technique was seen as being the most suitable for building
in areas with seismic risk. In this regard, the role of reinforced concrete in the recon-
struction of the two cities was fundamental. Studies of reinforced concrete construc-
tions had already been conducted for the earthquake of 1905. One example is that of
Mario Baratta, who accurately described some types of houses in a famous little book
entitled The new buildings in Calabria after the disastrous earthquake of 8 September
190514, but it was mainly the earthquake of 1908 and the need to provide immediate
answers to the problem of reconstructing the areas destroyed by the disaster, that
resulted in the experimentation of this new construction technique through the specific
sector of anti-seismic engineering. [14,15]
   In the first decade of the twentieth century, the theme of the earthquake-resistant
house becomes a field of investigation both for the technical testing and assessment of
the new material, as well as for the free exercise of various formal fantasies that drew
inspiration from the structural possibilities offered by reinforced concrete. (Figure 5)




                                                                                                            CONSERVATION SCIENCE IN CULTURAL HERITAGE




Figure 5. Attilio Muggia, Prog. n. 1883, Villino antisismico con ossatura in cemento armato, 1916,
India ink on paper. (Archivio Storico dell’Ordine degli Architetti di Bologna – cart. 3/23, H XXIX,
D V bis)


                                                                                                      243
                                                                                                                        It was even identified as being responsible for a real revolution in building history
                                                                                                                    because, as recalled by Daniele Donghi in the Introduction to his famous Architect’s
                                                                                                                    Manual, “[…] it could replace a variety of constructive elements and so create a new
                                                                                                                    kind of architecture, as happened with iron […]”. [16]
M. Licordari - The importance of seismic legislation and reinforced concrete in the reconstruction of the cities




                                                                                                                        Reinforced concrete, the protagonist of the beginning of the last century, became
                                                                                                                    the construction technique to use to build the perfect earthquake-resistant house, and
                                                                                                                    sometimes included quite daring projects. Among them, the project for the “city of
                                                                                                                    round houses” that Giuseppe Torres had hypothesized for the new Messina, or the
                                                                                                                    much more feasible project of the maison-domino by Le Corbusier. 15
                                                                                                                        But it is Daniele Donghi, with the previously mentioned Architect’s Manual who, in
                                                                                                                    the Appendix, devotes an entire chapter to building safety entitled “Sicurezza contro lo
                                                                                                                    sfasciamento e la rovina dei fabbricati”, in which he describes the aseismic qualities of
                                                                                                                    reinforced concrete. Further study of the seismic problem resumes some studies previ-
                                                                                                                    ously conducted by the same author on behalf of the “Comitato Veneto-Trentino Pro
                                                                                                                    Calabria e Sicilia”, formed immediately after the earthquake of 1908. In these studies,
                                                                                                                    Donghi argues as follows that:
                                                                                                                        “[…] reinforced cement concrete was the best known material for building houses
                                                                                                                    that were monolithic, undeformable and elastic, requirements for countries at risk of
                                                                                                                    earthquakes and additionally with the advantage of being indestructible and non-in-
                                                                                                                    flammable […]”.16
                                                                                                                        Afterwards, in the work Organi di difesa e sistemi di ricostruzione, published in Ven-
                                                                                                                    ice in 1909, Donghi reiterates the importance of reinforced concrete in the concept of
                                                                                                                    the earthquake-resistant home, when he writes that:
                                                                                                                        “a) to withstand earthquakes, buildings should have a homogeneous, monolithic,
                                                                                                                             elastic and non-deformable structure;
                                                                                                                        b) structures built with only timber and those in which the timber is responsible for
                                                                                                                             resistance, should be avoided;
                                                                                                                        c) structures cast in reinforced concrete (siderocemento) are the safest. Everyone
                                                                                                                            is in accordance with these conclusions […].”17[17]
                                                                                                                        With the same propagandistic intent, he describes the highly innovative character-
                                                                                                                    istics of this building material, claiming that it represented the best that could be found
                                                                                                                    for the construction of indestructible buildings, declaring that “[…] it is known that struc-
                                                                                                                    tures in reinforced concrete are made of cast cement with metal, combined in such a
                                                                                                                    way that the metal and cement bear the strain to which each is best suited, namely,
                                                                                                                    tensile stress and secondly, compressive stress[…]”.18 [16]
                                                                                                                        Donghi proposed different types of earthquake-resistant houses built with reinforced
                                                                                                                    concrete pillars, platbands, floors, roofs and concrete foundations. According to the
                                                                                                                    author, this “cage” of reinforced concrete made it possible to construct buildings with
                                                                                                                    two or three floors, making them earthquake-proof. He states that “all that is needed is
                                                                                                                    for the foundations to be well-calculated with respect to the ground, the building to be
                                                                                                                    well-anchored to it and for the floors and roofs to divide the strain evenly on the pillars
                                                                                                                    and platbands”.19
                                                                                                                        In addition, the results of an international competition, launched in 1909 by the “So-
                                                                                                                    cietà cooperativa lombarda di opere pubbliche”, aimed at identifying the most suitable
                                                                                                                    building method for reconstruction, officially approved the primacy of reinforced con-
                                                                                                                    crete over other construction techniques. It was Arturo Danusso, who was awarded the
                                                                                                                    highest prize. Danusso, who had trained with the Engineering Company, Porcheddu,
                                                                                                                    one of the most important Italian construction companies to operate with reinforced


                                                                                                              244
concrete, presented a written statement. In the statement, he argued that the solution
to the seismic problem was not to be found in a massive and overly rigid structure, but
in a lightweight structure able to gently oscillate during the quake without causing any
detachment.20 According to Danusso, only a reinforced concrete framework was able
to ensure all of these elements.[2]
    Among the aseismic structures envisaged for the reconstruction, the most recom-
mended construction technique involved the use of reinforced concrete frameworks.
However, as mentioned above, in the construction of the post-earthquake buildings
of the two cities of the Strait, the presence of anti-seismic regulations were strongly
restrictive. So, for normative requirements, the design of the framework of beams and
pillars in the reinforced concrete presented small equally spaced spans to facilitate
calculations and in addition, infill masonry of the “right” thickness.21 Therefore, while in
the rest of Europe reinforced concrete became more and more synonymous with large
spans, daring spaces, large glass windows, in early twentieth century southern Italy,
regular rigid structures were used, where the infill masonry played a key role in the
volumetric rigidity of the building. 22 [1, 2]
    In the prospectus and in the layout, the architectural language followed that of the
classical tradition. In fact, in observing the projects of many historic buildings in Reggio
and Messina it is immediately evident how the innovative spatial potential connected
to the use of reinforced concrete does not particularly influence the design of the build-
ings in the reconstruction. The spatial setting that predominates is a traditional one, in
which the dividing walls, incorporating and hiding the reinforced concrete frames, re-
strict and fragment the space, forgoing the flexibility and continuity of the environments
and the possibility of large openings independent from the load-bearing structures.
(Figure 6 a, b) [13, 18]




                                                                                                       CONSERVATION SCIENCE IN CULTURAL HERITAGE




Figure 6. Camillo Autore, Reggio Calabria, Casa Mazzitelli, plan ground floor (a) and the main
prospect (b), India ink and pencil on paper (Archivio Storico Comunale di RC – Commissione
Edilizia, B 15, fasc. 9).

   In the reconstruction of Reggio and Messina, the Hennebique system was the most
widely used thanks to the presence of specialized firms that were depositories of the
patent; the principal company, located in Turin, was that belonging to the engineer,
Porcheddu. The system, in this case, was adapted to the different needs of the place
and to the precise legislative requirements. Once again, therefore, the seismic legisla-
tion became the primary method of prevention and monitoring used by the municipali-
ties involved.


                                                                                                 245
                                                                                                                       3. The aseismic architectures of the reconstruction

                                                                                                                        In the early constructions of Reggio and Messina, many buildings had a framework
                                                                                                                    structure in reinforced concrete that was not limited to the beams and pillars but also
M. Licordari - The importance of seismic legislation and reinforced concrete in the reconstruction of the cities




                                                                                                                    included architraves and jambs for the windows which in part reproduced the wooden
                                                                                                                    frame design of the “baraccata” house for greater security. Solid bricks were used for
                                                                                                                    the foundations and the ground floor, while for the first floor perforated bricks were
                                                                                                                    adopted. Even the floors were in reinforced concrete, so as to constitute a slab that
                                                                                                                    was resistant but elastic in both directions. Compared to the frame only being in rein-
                                                                                                                    forced concrete, therefore, there were substantial differences in design in the buildings
                                                                                                                    of Reggio and Messina of the early twentieth century. This different way of building was
                                                                                                                    termed confined masonry construction (muratura confinata). There were three main
                                                                                                                    structural elements that characterized the “muratura confinata”: the main framework,
                                                                                                                    the secondary frame and the masonry. They were closely related to each other and
                                                                                                                    together, constituted the resistant structure of the building, representing at the same
                                                                                                                    time, the construction technique mostly adopted for many of the Strait’s buildings. [8]
                                                                                                                        In the project reports of many buildings of the reconstruction, in fact, it is not uncom-
                                                                                                                    mon to find the words “brick masonry with reinforced concrete cage”23. So, for exam-
                                                                                                                    ple, in the project of the Prefecture of Reggio Calabria, realized by the engineer Gino
                                                                                                                    Zani, it was specified that the main framework, containing special iron reinforcement
                                                                                                                    composed of rods connected to each other by spiral coils, included the basic frames of
                                                                                                                    the bond-beams and those at the top, the intersection of the upright posts of the walls
                                                                                                                    and partitions, and those needed for the completion of the vertical frames. The second-
                                                                                                                    ary framework, instead, included all the ribs, both vertical and horizontal, that had to
                                                                                                                    maintain the masonry work inside the meshes of the main framework, in other words
                                                                                                                    it had “to confine” the masonry. More specifically, therefore, it was the main framework
                                                                                                                    that had to resist seismic stresses, while the secondary framework, connected to the
                                                                                                                    main frame, was used to ‘stiffen’ it and give more stability. The aim of the latter, moreo-
                                                                                                                    ver, was to “[…] enclose, animate and consolidate the masonry work itself; to connect
                                                                                                                    it to the main upright elements and pre-stressed concrete beams and to frame the
                                                                                                                    doorways and windows […]”.24 [19]
                                                                                                                        The construction technique of confined masonry building, still very much in use
                                                                                                                    during the ‘50s, is a clear demonstration of how, in the areas of reconstruction, differ-
                                                                                                                    ent construction systems were used alongside the single reinforced concrete frame.
                                                                                                                    Among the proposed solutions for the construction in the field of experimentation
                                                                                                                    in reinforced concrete, those to be remembered are those of the engineer, Gino
                                                                                                                    Zani (1882-1964) for the city of Reggio Calabria; especially for the originality of the
                                                                                                                    building system used, based mainly on the prefabrication of the different structural
                                                                                                                    elements.
                                                                                                                        Gino Zani was a key figure in the post-earthquake reconstruction of Reggio
                                                                                                                    Calabria. His architecture, in fact, was a distinctive and original element in the urban
                                                                                                                    reconstruction of the city. It represented the most modern that Reggio was able to
                                                                                                                    conceive for its rebirth. His obstinacy in the choice of his designs and his technical
                                                                                                                    background allowed him to carry out the reconstruction of many parts of the city in
                                                                                                                    a short time, becoming a skilled architect and a talented urban planner; as well as
                                                                                                                    one of the precursors of modern earthquake-resistant constructions and prefabrica-
                                                                                                                    tion systems. For the city of Reggio, he was a sort of pioneer in the use of reinforced
                                                                                                                    concrete. (Figure 7) [8]


                                                                                                              246
   It was in the reconstruction of the city, that he noted the disadvantages of the con-
struction systems employed until then. He therefore proposed, among other structural
innovations, the use of concrete blocks of various types, but “[…] all based on one
type, so that they could be produced from one formwork simply by moving the internal
cores to form holes and recesses, arranging the metal reinforcement horizontally and
vertically inside the holes in the blocks and filling them with a concrete mix […]”. 25
   Overly convinced that a proper earthquake-resistant house could only be achieved
through the adoption of lightweight structures in reinforced concrete adequately
blocked at the base, the engineer from San Marino at a ministerial meeting in 1912,
convinced those present of the positive qualities of his earthquake-resistant house in
reinforced concrete, described by Zani himself as follows:




Figure 7. Gino Zani, Tavola 3 – Nervature (ribs) (LO CURZIO 1986)

   “[…] I imagine my aseismic house like a boat that is able to dance on the waves
without breaking up […] able to prevent the cracks in the ground from being transmit-
ted to the walls and to minimize the effects of the undulatory movements […]”26
   Zani’s constructional solutions were numerous and were repeatedly revised and im-
proved; the documents can still be found today in the Municipal Historical Archives of
the city of Reggio Calabria.27 They include various types of wall structures, simple and
reinforced, superimposed on a skeleton made of reinforced concrete or free-standing;
architraves with prefabricated elements instead of the usual wooden beam to accom-
modate the reinforcement and subsequent concrete casting; parapets anchored to
horizontal structures with beams or walls; coping to anchor the roofs, so as to avoid
                                                                                                                    any pressure; provision and reinforcement of bond-beams; stairs with beams and but-
                                                                                                                    tressed foundations; reinforced steps with bracket supports; floors with parallel and
                                                                                                                    crossed ribbing, either partially prefabricated or entirely cast in situ, with slim hollow
                                                                                                                    bricks and hollow blocks provided with reinforced links with ceilings in expanded sheet
M. Licordari - The importance of seismic legislation and reinforced concrete in the reconstruction of the cities




                                                                                                                    metal to form an air chamber or with the use of pumice of Lipari to obtain the necessary
                                                                                                                    thermal and acoustic insulation. [1, 8]
                                                                                                                       As previously mentioned, the most striking aspect of the rich and varied produc-
                                                                                                                    tion of Gino Zani is the special attention given to the design of prefabricated aseismic
                                                                                                                    structures. For instance, the prefabricated elements used to obtain beams and pillars,
                                                                                                                    which were completed with additional reinforcement and concrete casts, especially
                                                                                                                    at the junctions, enabled aseismic frames of considerable rigidity to be made and at
                                                                                                                    the same time eliminated the use of formworks. Another example involved reinforced
                                                                                                                    concrete floor slabs with parallel ribbing produced using metal formworks that made it
                                                                                                                    quick and easy to cast and then dismantle. 28
                                                                                                                       The houses built during the years of expansion in the north and south of the city
                                                                                                                    of Reggio, especially in the districts of St. Lucia, Mussolini, Mezzacapo and Gabelle,
                                                                                                                    had this kind of reinforced concrete structure. It was made up of primary and second-
                                                                                                                    ary upright posts, with a stringcourse frame in correspondence with the paving of the
                                                                                                                    raised floor, eave framing and bond-beams and architectural elements for dividing
                                                                                                                    spaces. The floors were made of reinforced concrete slabs with ribs; full bricks were
                                                                                                                    used for the outside walls of the ground floor and in the interior walls facing the stairs,
                                                                                                                    while hollow bricks were used for the exterior and interior walls of the top floors. The
                                                                                                                    foundations were of masonry stones and semi-hydraulic mortar, and the base frame
                                                                                                                    in reinforced concrete rested directly on top. Finally the terrace coverings, typical of
                                                                                                                    Mediterranean constructions, were constituted by an inclined slab covered with a
                                                                                                                    layer of asphalt overlaid with concrete tiles. 29 (Figure 8 a, b) [20]




                                                                                                                    Figure 8. Gino Zani, Tavola 6 – Casa asismica; Tavola 4 - Solai, Soffitti e Scale. (LO CURZIO 1986)



                                                                                                              248
    Over the years, other sophisticated tests involving the framework structure and also
the type of reinforcement to be adopted in the areas of the Strait were envisaged. One
of them proposed a very expensive solution which was however immediately aban-
doned. It consisted of a latticed metal framework, created by riveting with L profiles
and flat profiles; it was subsequently embedded in a cast of cement mix in order to
achieve a highly reinforced concrete structure. Other structures were also adopted us-
ing reinforced concrete, they did not however use a framework structure. This was the
case of the patented system produced by the Società Vianini30, which provided for the
construction of the building through the aggregation of independent blocks, each com-
prising one or two rooms, connected externally only to ensure continuity of prospects
and internally for communication between the rooms. Each block was substantially
monolithic, with its own foundation which was capable of fluctuating without affecting
adjacent elements. The system, however, failed to spread, while the reinforced con-
crete frame, with simplified reinforcement, continued to gain ground, spreading rapidly
also in those areas not affected by seismic risk. [2]
    As regards the new construction technique, however, there was some concern from
academic circles which advocated the use of reinforced concrete only for certain parts
of the building, in particular, the foundations that were to be “grade slab”. All this gave
rise to a real debate on the use of reinforced concrete, testified by the numerous
articles that appeared in magazines and newspapers of the towns affected by the
reconstruction at the time. In the “Gazzetta di Messina e delle Calabrie” of 5-6 May
191031, for example, a polemical article involving the engineer Giunta versus the en-
gineer Giovanni Salemi Pace was published on the use of reinforced concrete in the
earthquake-resistant buildings of Reggio and Messina. As a member of the commis-
sion for the study of building standards to be adopted for the municipalities interested
by the earthquake, Salemi had proposed, as the best preventive method, the use of
reinforced concrete frames; in this regard he had been criticized by Giunta, who was




                                                                                                    CONSERVATION SCIENCE IN CULTURAL HERITAGE
inclined to use a mixed system of reinforced concrete and masonry. The argument was
therefore full of conflicting theories. In many texts and treatises of the period, in fact,
the use of a reinforced concrete frame for the construction of the buildings of the Strait
was still the most recommended system. [21]
    Beyond the recommended construction systems, however, many of the buildings in
earthquake areas are the result of conditions imposed by seismic legislations enacted
after the earthquake of 1908. In the city of Reggio Calabria, starting from 1924 and
until 1935, it emerges how through legislative decrees precise provisions are given
both for the size of the buildings and for the construction of the walls.
    These laws concerned technical and hygiene aspects for the areas hit by the earth-
quake of 1908 (“Norme tecniche ed igieniche per le località colpite dal terremoto del
1908”) issued in the years: 1909 (Royal Decree (R.D.) 18 April 1909, n. 193), 1913
Consolidated law approved with Legislative Decree 19 August 1913), 1924 (R.D. 23
October 1924, n. 2089), 1927 (R.D. 13 March 1927, n. 431) and 1935 ( R.D. 25 March
1935, n. 640). They gave rise to the construction of many earthquake-resistant build-
ings in Reggio in the first decades of the twentieth century, in which the mixed struc-
ture and that in reinforced concrete were just some of the possibilities envisaged,
although later these would become the most widespread. In 1911, for the construction
of aseismic houses in Reggio and its province, for example, one company, the Soci-
età Anonima Cooperativa di costruzioni edilizie nella Provincia di Reggio Calabria, in


                                                                                              249
                                                                                                                    agreement with another, the Cooperativa Lombarda di LL.PP., proposed the following
                                                                                                                    building systems:
                                                                                                                         “[...] a) Constructions of timber frame with suitable and robust iron joints and mesh
                                                                                                                    filled with light material and inner tube, and light-weight covering in Marseille or Eternit
M. Licordari - The importance of seismic legislation and reinforced concrete in the reconstruction of the cities




                                                                                                                    tiles. The timber must be of excellent quality and strong essence such as larch, pine,
                                                                                                                    with special seismic foundations. b) Constructions with mixed frame for economic and
                                                                                                                    rustic houses with hollow concrete blocks, metal reinforcements arranged in hollow
                                                                                                                    vertical columns and horizontal joints; mesh filled with interlocking hollow blocks, par-
                                                                                                                    titions in concrete with a core of wire mesh or sheet metal, terrace roofing or Mar-
                                                                                                                    seille tiles. Special anti-seismic foundations. c) Civil constructions and buildings with
                                                                                                                    reinforced concrete framework strengthened using platband profiles placed close to
                                                                                                                    parabolic profiles and mesh filled with light-weight masonry, connected by metal rods
                                                                                                                    passing through the masonry vertically and horizontally and connecting to the rein-
                                                                                                                    forced structure itself. Terrace roofing with air chamber, waterproof hood, tiled flooring
                                                                                                                    or roofing in Marseille or Eternit tiles. Special anti-seismic foundations in grade slab
                                                                                                                    reinforced with concrete beams. d) Buildings with metal frameworks, exterior walls in
                                                                                                                    light-weight material, secured by metal mesh covered with cement plaster, including
                                                                                                                    partitions with a steel frame in sheet metal or light masonry with special reinforcement
                                                                                                                    and anti-seismic foundations […]”.32[22]
                                                                                                                         Once the most suitable building system had been chosen by the clients accord-
                                                                                                                    ing to their needs, the project was drawn up observing all the technical and hygienic
                                                                                                                    provisions required by the building code of the municipality concerned. In addition, in
                                                                                                                    a scale of 1 to 10, it was necessary to include detailed drawings of all the ribs, founda-
                                                                                                                    tions, struts, chords, frames for openings, slabs for floors and roofs; quantities of the
                                                                                                                    materials to be used, their quality and origin and test loads. In particular, for construc-
                                                                                                                    tions in reinforced concrete, it was obligatory to respect the regulations containing the
                                                                                                                    ministerial standards of 17 April 1907.33


                                                                                                                       4. Final considerations about the post-earthquake reconstruction

                                                                                                                        The reconstruction of Reggio Calabria and Messina was a huge urban planning
                                                                                                                    operation of building design and experimentation as had never happened before in
                                                                                                                    Italy. Its ultimate goal was to protect the sites in question from a future earthquake dis-
                                                                                                                    aster, without forgetting the possibility, tragically provided by nature, of making these
                                                                                                                    two cities, reconstructed ex novo, a tangible example of early twentieth century urban
                                                                                                                    concepts. It was an example in which urban design, in harmony with architectural
                                                                                                                    design, became an indispensable starting point for the redefinition of a city that had
                                                                                                                    been reduced to rubble by an earthquake and where planning efforts easily shifted
                                                                                                                    from designing buildings, streets, squares, stairways and gardens, to designing kiosks,
                                                                                                                    benches, lamp-posts, fences and gates.
                                                                                                                        Architects such as Camillo Autore, Ernesto Basile, Marcello Piacentini worked
                                                                                                                    carefully to redefine the new image that Reggio and Messina was to have, repeatedly
                                                                                                                    interpreting the poetics of the neoclassical and modernist style. In reality, however,
                                                                                                                    the modernist movement, which during the twenty years of the Fascist regime, should
                                                                                                                    have led to a formal renewal of the buildings, in this case, appeared to be an illusion34.
                                                                                                                    Even if simplified, the architectural language remained that of the classical tradition in
                                                                                                                    which, both the exterior and the interior of the building itself remained untouched by


                                                                                                              250
the formal innovations related to the advent of reinforced concrete. The organization
of the interior spaces and the articulation of the facade recalled the compositional
scheme of Renaissance buildings and consequently followed its architectural canons.
[23, 24]
    Thus, for example, the appearance of the most representative public buildings re-
ferred to a single compositional layout consisting of a slightly protruding central body,
generally tripartite with two symmetrical wings characterized by a succession of identi-
cal elements, and corner solutions, which were also symmetrical, protruding and often
defined by pilasters.35 Even private buildings were affected by the compromise be-
tween the stereotypes of the past and the new earthquake regulations adopted after
the earthquake. In the small private buildings of Reggio Calabria, for example, the
nineteenth-century layout and the Renaissance language coexisted, without trouble,
with the modest views. The stone ashlars and fake ashlars blended with the brick and
the ‘hammered’ plastering. Double lancet and triple lancet windows with architraves
alternated rhythmically on the side view of the different floors, and the portal character-
ized by two columns supporting a “short protruding balcony”, in accordance with the
city’s building code. 36
    It seemed an illusory desire to re-establish, through architecture, a historical order
that had abruptly been eliminated by the unexpected strength of nature. “New” cities,
therefore, were built with stylistic references that, on the one hand, testified to a desire
to build a sometimes overly lavish, fictitious past and, on the other hand, appeared to
be influenced by the architectural historicism in vogue at the time. The weight of history
and the reassuring use of tradition prevailed over the formal and stylistic innovations
related to the use of reinforced concrete. It was a return to the architectural canons of
the past in order to rebuild not only a city but also the historical memory of a people
whose cultural identity had been so hard hit.




                                                                                                     CONSERVATION SCIENCE IN CULTURAL HERITAGE
   5. Appendix: Short notes on today’s preventive methods

   The sad news of the earthquake of 24 August 2016, with epicenters in the provinces
of Rieti, Ascoli Piceno and Perugia, tragically reminds us that Italy is a territory of high
seismic risk. The news from the places of the disaster depict an area lacking the most
basic anti-seismic measures necessary for the safeguard of the town, both in the case
of old towns without seismic adaptations and in the not ‘up to standard’ construction of
new buildings. This sad story, consequently invites us to make some additional consid-
erations about today’s preventive methods.
   Nowadays, in Italy, seismic safety is achieved through the use of two important
tools: seismic regulations which, as seen, establish the criteria by which to build in
areas subject to seismic risk and seismic classification which catalogues the territo-
ry according to the seismic hazard in the different geographical areas. In Italy, from
1908 until 1974, it was only after the occurrence of telluric events that municipalities
were classified “at risk of earthquake” and therefore submitted to restrictive building
regulations. However, with the enactment of Law n.64 of 2 February in 1974, it was
established that seismic classification had to be based on proven technical-scientific
grounds and applied to the whole territory of Italy.
   Between 1981 and 1984, through criteria drawn up by the CNR, special ministerial
decrees were issued, that ensured the classification of about 45% of the territory under


                                                                                               251
                                                                                                                    examination. More than half of the territory, however, remained unclassified. Only after
                                                                                                                    the earthquake of 2002 that struck Puglia and Molise was it decided to act decisively
                                                                                                                    to complete the task. Through the Order of the President of the Ministers Council, no.
                                                                                                                    3274 of 2003, reclassification of the entire national territory was established in four
M. Licordari - The importance of seismic legislation and reinforced concrete in the reconstruction of the cities




                                                                                                                    different hazard levels. This represented an important turning point for Italy, because
                                                                                                                    it highlighted, definitively, that no area of the country could be considered unaffected
                                                                                                                    by the earthquake problem. The classification in question goes from grade 4 (gray
                                                                                                                    areas) attesting to minimum risk, up to grade 1 (red zones) representing the highest
                                                                                                                    level of danger; but starting from level 3 and up to level 1, aseismic planning was to be
                                                                                                                    considered mandatory.
                                                                                                                        Improvement in territorial monitoring, over the years, has been accompanied by
                                                                                                                    equivalent improvement in the law. The anti-seismic standards currently in force in Ital-
                                                                                                                    ian legislation date back to 2008; they are stated in the Ministerial Decree of January
                                                                                                                    14, published in the Official Gazette n.29 of 4 February 2008 - Ordinary Supplement
                                                                                                                    n.30. These new technical standards, describing in more detail the aspects set down
                                                                                                                    by Eurocode8 for construction in seismic areas, became mandatory from 1 July 2009
                                                                                                                    onwards, following the enactment of Law n.77 of 24 June 2009.
                                                                                                                        The Decree of 2008 is extremely important because it defines the principles for
                                                                                                                    planning, building and testing all earthquake-resistant buildings, at the same time,
                                                                                                                    guaranteeing that an accurate assessment is made of the static nature of public build-
                                                                                                                    ings (considered “strategic buildings”), such as schools, hospitals, churches, muse-
                                                                                                                    ums, bridges, etc. In the building design it indicates the minimum size of the pillars and
                                                                                                                    load-bearing walls and accurately defines architectural limits. Specifically, the layout
                                                                                                                    of the buildings must be regular and symmetrical, whereas the maximum height of the
                                                                                                                    building depends on the seismic classification of the territory: houses that fall in zone
                                                                                                                    1, for example, must not exceed two floors in height.
                                                                                                                        Therefore, when planning to build in a seismic zone, there are several things to
                                                                                                                    keep in mind, including of course the material to be adopted in constructions consid-
                                                                                                                    ered “safe”. Among the recommended aseismic materials we find reinforced concrete
                                                                                                                    either normal or pre-stressed, wood, steel and reinforced masonry. In constructing with
                                                                                                                    reinforced concrete the following points are defined: the minimum diameter of the steel
                                                                                                                    bars to be used for reinforcement (5 millimeters); the strength of the cement, which
                                                                                                                    varies from area to area depending on the seismic risk (class 8/10 is the minimum,
                                                                                                                    class 90/105 is the maximum); and the amount of steel to be used in proportion to
                                                                                                                    the cement, the so-called reinforcement of pillars and beams. If properly assembled
                                                                                                                    with mechanical joints, wood is also an excellent material for building earthquake-
                                                                                                                    resistant houses due to its characteristics of great flexibility and strength. Its history as
                                                                                                                    an aseismic material goes back in time to the “casa baraccata”, used by the Bourbon
                                                                                                                    Government after the earthquake of 1789 in Calabria and the “gaiola pombalina” of the
                                                                                                                    famous Marques de Pombal, used in Lisbon after the disastrous earthquake that de-
                                                                                                                    stroyed the city in 1755. Steel structures are also particularly suited to withstand earth-
                                                                                                                    quakes due to the ductile property of the material and its high flexibility and lightness.
                                                                                                                    In fact, if one starts from the premise that earthquake forces are associated to inertia
                                                                                                                    and thus connected to the mass of the structure, we can understand how, by reduc-
                                                                                                                    ing the mass, it automatically reduces the seismic forces in the design. This explains
                                                                                                                    why, in past earthquakes these structures have been shown to perform much better
                                                                                                                    than those built with heavier materials. Finally, the construction system of “reinforced
                                                                                                                    masonry” is also recommended because it is the natural evolution of the load-bearing


                                                                                                              252
masonry structures used for zones at greater risk of earthquakes and, if properly con-
structed, is considerably more ductile, behaving in a similar way to structures, such as
dividing walls, in reinforced concrete.
    In the planning phase, the structure’s resistance to a whole series of stresses is
obtained by applying the calculation rules described in detail in the law. An anti-seismic
building, in particular, must be able to resist torsion, deformation, cutting, bending,
vibration, cracking and corrosion. It is also necessary to assess the adhesion of the
steel bars to the concrete and, in the case of wooden constructions, the resistance to
tensile, bending and compression of the wood fiber itself.
    The ultimate aim of the anti-seismic construction is to build a structure that can
withstand as much as possible the action of the earthquake, thus delaying the to-
tal collapse of the building to save more lives. In addition to practical arrangements
related to the correct use of construction techniques, another part of the planning
includes other preventive methods to minimize damage. Among them it is worth men-
tioning, for example, strengthening certain parts such as dividing walls, stairwells,
elevator shafts which, if perfectly connected to the rest of the structure, tend to absorb
horizontal movements. Good preventive methods also include the careful design of
structural nodes (beams-pillars) with appropriate buttresses; the use of chains to in-
crease structural resistance; the adoption of seismic vibration dampers in the vicinity
of the structural joints; or implementing the criterion of “the hierarchy of resistances”
that envisages the design of a structure in which the plastic hinges that generate the
collapse is formed first in the beams, then in the pillars, so as to delay the general
collapse of the building. [25, 26]
    Currently, there is a tendency to replace the traditional frame in reinforced concrete,
consisting of pillars and beams, with a structure of internal and external deep beams
with different orientations linked directly with the flat slabs. There are also recent stud-
ies based on the possibility of building structures capable of modifying their structural
elasticity in relation to the seismic shock that strikes them. Known as seismic isolation,




                                                                                                     CONSERVATION SCIENCE IN CULTURAL HERITAGE
it became established especially after the Kobe earthquake of 1995. The new seismic
method consists in putting a horizontally deformable device between the ground and
the supporting base of the structure. The device is called a seismic isolator which,
in most cases, is made from layers of high bearing capacity rubber alternated with
layers of steel plate bonded together; these are interrupted centrally by a damper,
which generally consists of a ductile metal. Used mainly for the construction of pub-
lic buildings, such as schools, this system is not applicable to very high buildings or
when the supporting soil is very soft. In this case, instead of insulating the foundations,
structures can be designed with a ductility capable of dissipating plastically the energy
transmitted to the construction by the earthquake. Energy dissipation must take place
in strategic points, planned in the design phase, so that they are able to withstand large
displacements. [27, 28]
    The superiority of structures with seismic isolation systems compared to those with
fixed base systems, is motivated by the fundamentally diverse oscillation period. In
fact, while the frequencies of structures in reinforced concrete with fixed base coincide
with the majority of earthquake frequencies which, through the phenomenon of reso-
nance in the elastic range, lead to the amplification of the shock effects, in structures
equipped with “seismic isolation” it is possible to design an isolated structure with a
much lower frequency than that of earthquakes. The result is a much more resist-
ant structure, because it significantly reduces the horizontal forces transmitted by the


                                                                                               253
                                                                                                                    earthquake to the building. Seismic protection of this kind is therefore of a high level
                                                                                                                    and greatly limits overall damage. [29]
M. Licordari - The importance of seismic legislation and reinforced concrete in the reconstruction of the cities




                                                                                                                        Acknowledgments

                                                                                                                        I would like to thank Professor Lorusso for his assistance and advice.


                                                                                                                        Notes
                                                                                                                    1
                                                                                                                      For details, see: SIMONE, La città di Messina tra norma e forma, Roma, Gangemi editore, 1996,
                                                                                                                    p. 111.
                                                                                                                    2
                                                                                                                       Cf. BARUCCI, La casa antisismica: prototipi e brevetti; materiali per una storia delle tecniche e
                                                                                                                    del cantiere. Roma, Gangemi, 1990, pp. 165-167.
                                                                                                                    3
                                                                                                                      Ibid.
                                                                                                                    4
                                                                                                                       Norme tecniche ed igieniche obbligatorie per le riparazioni, ricostruzioni e nuove costruzioni
                                                                                                                    degli edifici pubblici e privati nei Comuni colpiti dal terremoto del 28 dicembre 1908 o da altri an-
                                                                                                                    teriori, R.D. 18 aprile 1909, n. 193, art. 3 (Published in the Gazzetta Ufficiale n. 95, 22 April 1909).
                                                                                                                    5
                                                                                                                      Norme tecniche ed igieniche obbligatorie..., cit., art. 10.
                                                                                                                    6
                                                                                                                      Norme tecniche ed igieniche obbligatorie..., cit., art. 16.
                                                                                                                    7
                                                                                                                      Norme tecniche ed igieniche obbligatorie..., cit., art. 18.
                                                                                                                    8
                                                                                                                      Norme tecniche ed igieniche obbligatorie..., cit., art. 22.
                                                                                                                    9
                                                                                                                      Cf. FERA, La città antisismica: storia, strumenti e prospettive della pianificazione territoriale per
                                                                                                                    la riduzione del rischio sismico. Roma, Gangemi, 1991, p. 94.
                                                                                                                    10
                                                                                                                       For details, see: COLISTRA, Reggio Calabria: l’architettura e la città. (Collana del Dipartimento
                                                                                                                    di architettura e analisi della città mediterranea. Quaderni della ricerca), Jason stampa, 1999, in
                                                                                                                    particular the chapter entitled “Gli elementi dell’architettura”.
                                                                                                                    11
                                                                                                                       Cf. COLISTRA, Reggio Calabria: l’architettura e la città…, op. cit.
                                                                                                                    12
                                                                                                                       Cf. SIMONE, La città di Messina tra norma e forma, Roma, Gangemi editore, 1996, p. 71.
                                                                                                                    13
                                                                                                                       Cf. FERA, La città antisismica: storia, strumenti…, op. cit., pp. 100-101.
                                                                                                                    14
                                                                                                                       Analyzing several kinds of houses designed by the engineer Accusani for the town of Favel-
                                                                                                                    loni, Baratta described the aseismic typologies adopted : “[…] The houses adopt a construction
                                                                                                                    system in reinforced concrete constituted by a vertical pillar structure with horizontal beams and
                                                                                                                    girders, so as to form a frame in rigid béton, then closed with thin walls and slabs of the same
                                                                                                                    material [...]. The openings between the vertical reinforcement, the base frame and the overlying
                                                                                                                    horizontal beams are closed by masonry made with small parallelepiped blocks with double ho-
                                                                                                                    les, produced with pumice concrete and joined together using cement mortar; air circulates in
                                                                                                                    the holes which serves as insulation [...]. The partitions, of variable thickness are also built with
                                                                                                                    small blocks [...]. Some of these rectangular blocks, for greater security, are reinforced section
                                                                                                                    by section with vertical round rods and cement […].” Cf. BARATTA, Le nuove costruzioni in Cala-
                                                                                                                    bria dopo il disastroso terremoto dell’8 settembre 1905, Modena, Società Tipografica Modenese,
                                                                                                                    1908, pp. 80-83.
                                                                                                                    15
                                                                                                                        In reality, there is no trace of the two cities in the projects of Le Corbusier and Torres this is
                                                                                                                    because, once again the use of reinforced concrete is strongly restricted due to the presence of
                                                                                                                    aseismic legislation that limited the formal freedom of the designers by imposing a rigid approach
                                                                                                                    in the design of the buildings.
                                                                                                                    16
                                                                                                                       DONGHI, Manuale dell’architetto, Appendix , p. 145.
                                                                                                                    17
                                                                                                                       DONGHI, Organi di difesa e sistemi di ricostruzione, Venezia 1909, pp. 18-19.
                                                                                                                    18
                                                                                                                        This is a highly advantageous combination compared to non-reinforced concrete monoliths,
                                                                                                                    because, as they have the same resistance, the dimensions of the reinforced concrete are much
                                                                                                                    smaller than those of the simple concrete and because the composition of this material has a
                                                                                                                    higher degree of elasticity than the limited elasticity of simple concrete. DONGHI, Manuale…,
                                                                                                                    op. cit. pp. 35-37.


                                                                                                              254
19
    Ibid.
20
    In the text, the engineer also speaks of the dynamics of the structures, in which he physically
establishes the relationship between the resistance of a building, its mass and its flexibility. See:
DANUSSO, La statica delle costruzioni antisismiche, in “ Il Monitore Tecnico”, 33, 1909, pp. 641-
645.
21
    For details, see: IORI, Il cemento armato in Italia: dalle origini alla seconda guerra mondiale.
Roma, Edilstampa, 2001.
22
    Cf. IORI, Il cemento armato in Italia…, op. cit. For more details on the concrete story, see:
SIMONNET, Le bèton: histoire d’un materiaux: économie, technique, architecture. Marseille, Ed.
Parenthèses, 2005.
23
    Corpo Reale del Genio Civile, Edificio per la sede della R. Prefettura di Reggio Cal., Capitolato
speciale d’appalto. Roma, Cooperativa Tipografica Manunzio, 1914, pp. 19-20.
24
    Ibid.
25
    Cf. LO CURZIO, L’architettura di Gino Zani per la ricostruzione di Reggio Calabria. Gangemi,
1986, p. 17.
26
    Ibid.
27
    Cf. LICORDARI, L’utilizzo del cemento armato nella ricostruzione delle città dello Stretto dopo
il terremoto del 1908. Roma, Aracne Editrice, 2016.
28
    LO CURZIO, L’architettura di Gino Zani…, op. cit., p. 28.
29
    Cf. Ente Edilizio di Reggio Calabria, Ufficio Tecnico, Progetto per la costruzione di case econo-
miche, relazione descrittiva. Reggio Calabria, 18 dicembre 1927. (ASRC, 10.8.3 , B 103).
30
    Patent n. 100064, G.Vianini & C.; see IORI, op. cit, Note p. 105.
31
    GIUNTA, Discussione libera in tema di costruzioni, in “Gazzetta di Messina e delle Calabrie”,
5-6 Maggio 1910.
32
    Convenzione tra la Cooperativa Lombarda di LL.PP. e la Cooperativa di costruzioni edilizie
nella Provincia di Reggio Calabria. Reggio Calabria, 1911, pp. 2-3. (ASRC, D.P. B11/634).
33
    Ibid.
34
    Cf. COLISTRA, Reggio Calabria: l’architettura e la città…, op. cit.
35
    Cf. ARICO’, MILELLA. Riedificare contro la storia. Roma, Reggio Calabria. 1984.
36
    Ibid.




                                                                                                              CONSERVATION SCIENCE IN CULTURAL HERITAGE
      References

[1]     Licordari, M. (2016). L’utilizzo del cemento armato nella ricostruzione delle città
        dello Stretto dopo il terremoto del 1908. Roma: Aracne Editrice.
[2]     Iori, T. (2001). Il cemento armato in Italia: dalle origini alla seconda guerra mon-
        diale. Roma: Edilstampa.
[3]     Simone, R. (1996). La città di Messina tra norma e forma. Roma: Gangemi edi-
        tore.
[4]     Fera, G. (1991). La città antisismica: storia, strumenti e prospettive della piani-
        ficazione territoriale per la riduzione del rischio sismico. Roma: Gangemi edi-
        tore.
[5]     Barucci, C. (1990). La casa antisismica: prototipi e brevetti; materiali per una
        storia delle tecniche e del cantiere. Roma: Gangemi editore.
[6]     R. D. n. 193, 18 aprile 1909, Norme tecniche ed igieniche obbligatorie per le
        riparazioni, ricostruzioni e nuove costruzioni degli edifici pubblici e privati nei
        Comuni colpiti dal terremoto del 28 dicembre 1908 o da altri anteriori, in Gazzetta
        Ufficiale n. 95, 22 aprile.
[7]     Colistra, D. (1999). Reggio Calabria: l’architettura e la città. (Collana del Dipar-
        timento di architettura e analisi della città mediterranea. Quaderni della ricerca).
        Reggio Calabria: Jason stampa.


                                                                                                        255
                                                                                                                    [8]    Lo Curzio, M. (1986). L’architettura di Gino Zani per la ricostruzione di Reggio
                                                                                                                           Calabria. Roma: Gangemi editore.
                                                                                                                    [9]    Cagliostro, R. M. (1981). Ricostruzioni e linguaggi: Reggio Calabria per una sto-
                                                                                                                           riografia delle scritture architettoniche dopo il 1908. Reggio Calabria: Casa del
M. Licordari - The importance of seismic legislation and reinforced concrete in the reconstruction of the cities




                                                                                                                           libro.
                                                                                                                    [10]   Zucconi, G. (1989). La città contesa. Dagli ingegneri sanitari agli urbanisti (1885
                                                                                                                           – 1942). Milano: Jaca Book.
                                                                                                                    [11]   Calabi, D. (2004). Storia dell’urbanistica europea: questioni, strumenti, casi es-
                                                                                                                           emplari. Milano: Bruno Mondadori.
                                                                                                                    [12]   Sitte, C. (1981). L’arte di costruire la città: l’urbanistica secondo i suoi fondamenti
                                                                                                                           artistici. Milano: Jaca Book.
                                                                                                                    [13]   Milella, O., Marino, A. (1988). La catastrofe celebrata: architetture e città a Reg-
                                                                                                                           gio dopo il 1908. Roma: Gangemi editore.
                                                                                                                    [14]   Baratta, M. (1907). A proposito del nuovo codice di edilizia sismica per le
                                                                                                                           Calabrie, Perugia: Tip. Guerra.
                                                                                                                    [15]   Baratta, M. (1908). Studio delle nuove costruzioni in Calabria dopo il disastroso
                                                                                                                           terremoto dell’8 settembre 1905. Modena: Società Tipografica Modenese.
                                                                                                                    [16]   Donghi, D. (1935). Manuale dell’architetto. Torino: UTET.
                                                                                                                    [17]   Donghi, D. (1909). Organi di difesa e sistemi di costruzione nei paesi colpiti fre-
                                                                                                                           quentemente da terremoti, Rivista di ingegneria sanitaria, V, n. 6.
                                                                                                                    [18]   Cagliostro, R. M. (1986). Giudicare per immagini: Reggio Calabria e il suo territo-
                                                                                                                           rio nei disegni ottocenteschi dell’Archivio di Stato. Facoltà di Architettura di Reg-
                                                                                                                           gio Calabria, saletta del centro audiovisivo, 5-15 giugno 1986. Roma: Gangemi
                                                                                                                           editore.
                                                                                                                    [19]   Corpo Reale del Genio Civile. 1914. Edificio per la sede della R. Prefettura
                                                                                                                           di Reggio Cal., Capitolato speciale d’appalto. Roma, Cooperativa Tipografica
                                                                                                                           Manunzio, 1914, pp. 19-20.
                                                                                                                    [20]   Ente Edilizio di Reggio Calabria, 1927. Progetto per la costruzione di case eco-
                                                                                                                           nomiche, relazione descrittiva. Reggio Calabria, 18 dicembre 1927 (ASRC,
                                                                                                                           10.8.3 , B 103).
                                                                                                                    [21]   Giunta. 1910. Discussione libera in tema di costruzioni, in Gazzetta di Messina e
                                                                                                                           delle Calabrie, 5-6 Maggio.
                                                                                                                    [22]   Convenzione tra la Cooperativa Lombarda di LL.PP. e la Cooperativa di costru-
                                                                                                                           zioni edilizie nella Provincia di Reggio Calabria. Reggio Calabria, 1911, pp. 2-3
                                                                                                                           (ASRC, D.P. B11/634).
                                                                                                                    [23]   Aricò, N., Milella, O. (1984). Riedificare contro la storia. Roma: Gangemi editore.
                                                                                                                    [24]   Valtieri, S. (2008). 28 dicembre: la grande ricostruzione dopo il terremoto del
                                                                                                                           1908 nell’area dello Stretto. Roma: CLEAR.
                                                                                                                    [25]   Reitherman, R.K. (2012). Earthquakes and engineers: An international history.
                                                                                                                           Virginia: ASCE.
                                                                                                                    [26]   Khan, R. A. 2014. Performance Based Seismic Design of reinforced concrete
                                                                                                                           building, International Journal of Innovative Research in Science, Engineering
                                                                                                                           and Technology, Vol. 3, Issue 6, June.
                                                                                                                    [27]   Paulay, T., Priestley, M.J.N. (1992). Seismic design of reinforced concrete and
                                                                                                                           masonry buildings. Chichester: John Wiley & Sons.
                                                                                                                    [28]   Pampanin, S. (2005). Emerging solutions for high seismic performance of pre-
                                                                                                                           cast-prestressed concrete buildings. Journal of Advanced Concrete Technology,
                                                                                                                           3, pp. 202-222.


                                                                                                              256
[29] Phocas, M.C. (2013). Initiations and Future Directions in the Development of
     Kinetic Structures for Earthquake Resistance, J Archit Eng Tech S10:e001.
     doi:10.4172/2168-9717.S10-e001


   Biographical notes

    Mariangela Licordari is a PhD candidate in History of Architecture at the University
Paris1 Panthéon-Sorbonne of Paris and the Universidade Nova of Lisbon (FCSH).
Particularly interested in architecture of the twentieth century, she is currently engaged
in the study of the Portuguese architecture of the Modern Movement. She graduated
in “Architecture” at the IUAV of Venice (2010) and in “History and Preservation of Archi-
tectural and Environmental Heritage” at the Faculty of Architecture of Reggio Calabria
(2004); in May 2006 she completed a Master CIPAA at the Politecnico di Milano; in July
2013, the Master Erasmus Mundus TPTI at the University Paris1 Panthéon-Sorbonne
and in October 2015, the DEA in Contemporary Art History at the Universidade Nova
of Lisbon.




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