Pavement Distress Detection Methods: A Review
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paper_title: Comprehensive performance indicators for road pavement condition assessment

paper_content:

AbstractThe selection and use of technical parameters and performance indicators plays an essential role in the pavement management process. It is known that if more parameters are used, a more accurate evaluation of pavement condition is achieved, improving the choice of maintenance and rehabilitation interventions. However, one of the most expensive activities of the pavement management process is data collection. Accordingly, it is necessary to find a balance between the data collected and the real needs of the process. This paper presents a new approach for the development of pavement condition indicators using a machine learning algorithm named regularised regression with lasso. The present discussion is supported by a case study, which compares the proposed method with current practice for the description of the condition of a Portuguese motorway. The results suggest that the application of machine learning methods can improve the accuracy of pavement condition indicators when less data are availabl...
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paper_title: Review of multicriteria-analysis methods application in decision making about transport infrastructure

paper_content:

U radu je obrazložena složena problematika donosenja odluka o prometnoj infrastrukturi u urbanim podrucjima te analizirana primjena metoda visekriterijske analize u tom procesu. Analizom je obuhvaceno planiranje, projektiranje, održavanje i rekonstrukcija prometne infrastrukture. Autori u radu daju zakljucke o mogucnostima, prednostima i ogranicenjima primjene metoda visekriterijske analize u cilju unapređenja kvalitete donosenja odluka o prometnoj infrastrukturi u urbanim podrucjima.
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paper_title: A Review of Three-Dimensional Imaging Technologies for Pavement Distress Detection and Measurements

paper_content:

With the ever-increasing emphasis on maintaining road assets to a high standard, the need for fast accurate inspection for road distresses is becoming extremely important. Surface distresses on roads are essentially three dimensional (3-D) in nature. Automated visual surveys are the best option available. However, the imaging conditions, in terms of lighting, etc., are very random. For example, the challenge of measuring the volume of the pothole requires a large field of view with a reasonable spatial resolution, whereas microtexture evaluation requires very accurate imaging. Within the two extremes, there is a range of situations that require 3-D imaging. Three-dimensional imaging consists of a number of techniques such as interferometry and depth from focus. Out of these, laser imagers are mainly used for road surface distress inspection. Many other techniques are relatively unknown among the transportation community, and industrial products are rare. The main impetus for this paper is derived from the rarity of 3-D industrial imagers that employ alternative techniques for use in transportation. In addition, the need for this work is also highlighted by a lack of literature that evaluates the relative merits/demerits of various imaging methods for different distress measurement situations in relation to pavements. This overview will create awareness of available 3-D imaging methods in order to help make a fast initial technology selection and deployment. The review is expected to be helpful for researchers, practicing engineers, and decision makers in transportation engineering.
---
paper_title: Incorporating Road Safety into Pavement Management

paper_content:

Improving road safety through proper pavement engineering and maintenance should be one of the major objectives of pavement management systems. When pavements are evaluated in terms of safety, a number of factors related to pavement engineering properties are raised, such as pavement geometric design, paving materials and mix design, pavement surface properties, shoulder type, and pavement color and visibility. Each year there are voluminous annual reports on traffic accident statistics and discussions of such road safety issues as road safety modeling and pavement safety measurements and criteria. Although road safety may be considered a separate area, it should be incorporated into pavement management systems. The main pavement engineering relationships associated with road safety are identified, and the various aspects of road safety related to pavement management, such as pavement types, pavement surface macrotexture and microtexture, and pavement safety measurements, criteria, and evaluation methods, are discussed. A systematic approach is proposed for the coordination of pavement maintenance programs with road safety improvement and the incorporation or integration of safety management with pavement and other management systems. Finally, a list of possible remedial measures for road safety improvements associated with pavement maintenance activities is recommended.
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paper_title: Sustainable Pavement Management System in Urban Areas Considering the Vehicle Operating Costs

paper_content:

Urban roads constitute most of the existing roads and they are directly managed by small administrations. Normally, these small administrations do not have sufficient funds or sufficient qualified personnel to carry out this task. This paper deals with an easy-implementation Pavement Management System (PMS) to develop strategies to maintain, preserve and rehabilitate urban roads. The proposed method includes the creation of the road network inventory, the visual surveys of the pavement and the evaluation of its condition by the Pavement Condition Index (PCI). The method intends to give a valid tool to road managers to compare alternative maintenance strategies and perform the priority analysis on the network. With this aim, the procedure assesses the Vehicle Operating Costs (VOC) by a written regression between PCI and International Roughness Index (IRI). The proposed method has several advantages because it can be easily adapted to various situations and it does not require a large amount of time and money for its implementation.
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paper_title: Investigating effects of asphalt pavement conditions on traffic accidents in Tennessee based on the pavement management system (PMS)

paper_content:

Pavement maintenance is essential for ensuring good riding quality and avoiding traffic congestion, air pollution, and accidents. Improving road safety is one of the most important objectives for pavement management systems. This study utilized the Tennessee Pavement Management System (PMS) and Accident History Database (AHD) to investigate the relationship between accident frequency and pavement distress variables. Focusing on 4 urban interstates with asphalt pavements, divided median types, and 55 mph speed limits, 21 Negative Binomial Regression models were developed to predict various types of traffic accident frequencies based on different pavement condition variables, including rut depth (RD), International Roughness Index (IRI), and Present Serviceability Index (PSI). Modeling results indicated that the RD models did not perform well, except for predicting accidents at night and accidents under rain weather conditions; whereas, IRI and PSI were always significant prediction variables in all types of accident models. Comparing the models goodness-of-fit results, it was found that the PSI models had a better performance in crash frequency prediction than the RD models and IRI models. This study suggests that the PSI accident prediction models should be considered as a comprehensive approach to integrate the highway safety factors into the PMS.
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paper_title: A review on automated pavement distress detection methods

paper_content:

In recent years, extensive research has been conducted on pavement distress detection. A large part of these studies applied automated methods to capture different distresses. In this paper, a literature review on the distresses and related detection methods are presented. This review also includes commercial solutions. Thereafter, a gap analysis is conducted which is concluded that in particular the distresses related to pavement micro-texture need serious additional research in order to be implemented in a cost-effective fashion. Depth-related distresses are detectible fairly well, but rely on expensive tools.
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paper_title: Development of Overall Pavement Condition Index for Urban Road Network

paper_content:

Abstract Pavements are major assets of highway infrastructure. Maintenance and rehabilitation of these pavements to the desired level of serviceability is one of the challenging problems faced by pavement engineers and administration in the highway sector. The evaluation of pavement performance using pavement condition indicators is a basic component of any Pavement Management System. Various indicators like Pavement Condition Index (PCI), Present Serviceability Rating (PSR), Roughness Index (RI), etc. have been commonly used to assign a maintenance strategy for the existing pavements. The present paper is an effort in the similar direction, to develop a combined Overall Pavement Condition Index (OPCI) for the selected network of Noida urban roads. The study area consists of 10 urban road sections constituting 29.92 km of Noida city. The methodology includes identification of urban road sections, pavement distress data collection, development of individual distress index and finally developing a combined OPCI for the network. The four performance indices viz. Pavement Condition Distress Index (PCI Distress ), Pavement Condition Roughness Index (PCI Roughness ), Pavement Condition Structural Capacity Index (PCI Structure ) and Pavement Condition Skid Resistance Index (PCI Skid ) are developed individually. Then all these indices are combined together to form an OPCI giving importance of each indicator. The proposed index is expected to be a good indicative of pavement condition and performance. The developed OPCI was used to select the maintenance strategy for the pavement section.
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paper_title: Data collection technologies for road management

paper_content:

Different types of data are required for managing the road infrastructure. Inventory data describe the physical elements of a road system. Condition data describe the condition of elements that can be expected to change over time. There are a wide range of technologies available to the road manager for measuring attributes of the road network. The challenge is to select the appropriate equipment, given local conditions and the way in which the data are expected to be used. The purpose of this note is to give a general view of the currently available survey technologies applied to pavements, bridges and traffic. This includes an assessment of the applicability of these technologies in developing countries. The goal is to assist managers in establishing an appropriate and sustainable e data collection program and procuring the appropriate equipment to collect the data. This note is a summary of the report 'Data Collection Technologies for Road Management' (see report no. 37372). The note opens with a discussion of data collection requirements. This is then followed by separate discussions on pavements, bridges and traffic survey technologies. A cost/performance analysis between available equipment is presented in each section. Finally, recommendations for data collection are presented as a guidance to managers in developing countries.
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paper_title: A Specified Procedure for Distress Identification and Assessment for Urban Road Surfaces Based on PCI

paper_content:

In this paper, a simplified procedure for the assessment of pavement structural integrity and the level of service for urban road surfaces is presented. A sample of 109 Asphalt Concrete (AC) urban pavements of an Italian road network was considered to validate the methodology. As part of this research, the most recurrent defects, those never encountered and those not defined with respect to the list collected in the ASTM D6433 have been determined by statistical analysis. The goal of this research is the improvement of the ASTM D6433 Distress Identification Catalogue to be adapted to urban road surfaces. The presented methodology includes the implementation of a Visual Basic for Application (VBA) language-based program for the computerization of Pavement Condition Index (PCI) calculation with interpolation by the parametric cubic spline of all of the density/deduct value curves of ASTM D6433 distress types. Also, two new distress definitions (for manholes and for tree roots) and new density/deduct curve values were proposed to achieve a new distress identification manual for urban road pavements. To validate the presented methodology, for the 109 urban pavements considered, the PCI was calculated using the new distress catalogue and using the ASTM D6433 implemented on PAVERTM. The results of the linear regression between them and their statistical parameters are presented in this paper. The comparison of the results shows that the proposed method is suitable for the identification and assessment of observed distress in urban pavement surfaces at the PCI-based scale.
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paper_title: Incorporating Road Safety into Pavement Management

paper_content:

Improving road safety through proper pavement engineering and maintenance should be one of the major objectives of pavement management systems. When pavements are evaluated in terms of safety, a number of factors related to pavement engineering properties are raised, such as pavement geometric design, paving materials and mix design, pavement surface properties, shoulder type, and pavement color and visibility. Each year there are voluminous annual reports on traffic accident statistics and discussions of such road safety issues as road safety modeling and pavement safety measurements and criteria. Although road safety may be considered a separate area, it should be incorporated into pavement management systems. The main pavement engineering relationships associated with road safety are identified, and the various aspects of road safety related to pavement management, such as pavement types, pavement surface macrotexture and microtexture, and pavement safety measurements, criteria, and evaluation methods, are discussed. A systematic approach is proposed for the coordination of pavement maintenance programs with road safety improvement and the incorporation or integration of safety management with pavement and other management systems. Finally, a list of possible remedial measures for road safety improvements associated with pavement maintenance activities is recommended.
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paper_title: Sustainable Pavement Management System in Urban Areas Considering the Vehicle Operating Costs

paper_content:

Urban roads constitute most of the existing roads and they are directly managed by small administrations. Normally, these small administrations do not have sufficient funds or sufficient qualified personnel to carry out this task. This paper deals with an easy-implementation Pavement Management System (PMS) to develop strategies to maintain, preserve and rehabilitate urban roads. The proposed method includes the creation of the road network inventory, the visual surveys of the pavement and the evaluation of its condition by the Pavement Condition Index (PCI). The method intends to give a valid tool to road managers to compare alternative maintenance strategies and perform the priority analysis on the network. With this aim, the procedure assesses the Vehicle Operating Costs (VOC) by a written regression between PCI and International Roughness Index (IRI). The proposed method has several advantages because it can be easily adapted to various situations and it does not require a large amount of time and money for its implementation.
---
paper_title: Investigating effects of asphalt pavement conditions on traffic accidents in Tennessee based on the pavement management system (PMS)

paper_content:

Pavement maintenance is essential for ensuring good riding quality and avoiding traffic congestion, air pollution, and accidents. Improving road safety is one of the most important objectives for pavement management systems. This study utilized the Tennessee Pavement Management System (PMS) and Accident History Database (AHD) to investigate the relationship between accident frequency and pavement distress variables. Focusing on 4 urban interstates with asphalt pavements, divided median types, and 55 mph speed limits, 21 Negative Binomial Regression models were developed to predict various types of traffic accident frequencies based on different pavement condition variables, including rut depth (RD), International Roughness Index (IRI), and Present Serviceability Index (PSI). Modeling results indicated that the RD models did not perform well, except for predicting accidents at night and accidents under rain weather conditions; whereas, IRI and PSI were always significant prediction variables in all types of accident models. Comparing the models goodness-of-fit results, it was found that the PSI models had a better performance in crash frequency prediction than the RD models and IRI models. This study suggests that the PSI accident prediction models should be considered as a comprehensive approach to integrate the highway safety factors into the PMS.
---
paper_title: A review on automated pavement distress detection methods

paper_content:

In recent years, extensive research has been conducted on pavement distress detection. A large part of these studies applied automated methods to capture different distresses. In this paper, a literature review on the distresses and related detection methods are presented. This review also includes commercial solutions. Thereafter, a gap analysis is conducted which is concluded that in particular the distresses related to pavement micro-texture need serious additional research in order to be implemented in a cost-effective fashion. Depth-related distresses are detectible fairly well, but rely on expensive tools.
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paper_title: Managing sidewalk pavement maintenance: A case study to increase pedestrian safety

paper_content:

Comfort is a major requirement in planning pedestrian facilities. Pedestrians walk where they feel comfortable and when they do not feel at ease, they walk elsewhere. A typical example is that filthy, distressed, or too narrow sidewalks induce pedestrians to walk on carriageways. This behaviour jeopardizes road safety and highly dangerous to most users, leave them vulnerable. Unsuitable pavements can be the result of irregular maintenance operations to restore evenness after shock damage, weather phenomena, installation of equipment (e.g., posts, fences, urban furniture) with a reduction of walkable surface, or substandard repair work on pavements and patches due to emergency operations. These problems can be solved with an appropriate maintenance management system, which optimizes financial resources to make smart decisions about how to intervene with an adequate and lasting maintenance operation. This paper defines an evaluation index for sidewalk conditions as a part of an efficient set-up of a Sidewalk Management System, which is similar to the better known Road Management System. The study relies on surveys, as well as the classification and analysis of sidewalk distresses. The authors adapted an index already standardized by ASTM for roads and airports: the Pavement Condition Index (PCI). PCI has been modified to consider the specific types on the sidewalks studied within this paper. To validate the method, a case study of a residential district in Rome, Italy, was carried out. The chosen area lacks regular maintenance and has therefore resulted in a network of unsafe sidewalks. Frequent detour routes were surveyed and related to the level of distresses within a general assessment of safety. This study concentrates on sidewalks with flexible pavements because this type of pavement is the only one adopted in the survey areas and, in general, throughout Italy.
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paper_title: Rutting in Flexible Pavement: An Approach of Evaluation with Accelerated Pavement Testing Facility☆

paper_content:

The majority of roads in India are constructed of flexible pavements, wherein, the bulk of distress is in the form of either cracking (fatigue) or rutting (permanent deformation). Rutting is the longitudinal depression in the wheel path in bituminous pavements, which can be attributed to excessive consolidation, formed by an accumulation of permanent deformations caused by repeated heavy loads, or lateral movement of the material, caused by shear failure of the bituminous concrete layer, or a combination of both mechanisms. There are countries facing functional constraints on their flexible road pavements due to rutting and trying to resolve this failure. Rutting in pavement is a serious mode of distress beside fatigue in bituminous pavement in high temperature areas, including India, and may lead to premature failure in pavements and result in early and costly rehabilitation. In addition, rutting in pavements causes hydroplaning and severe physiological and safety concern for users. Premature distress and associated problems in pavement result in an economic burden on the tax payer. Hence, this problems needs to be properly addressed through evaluation and mitigation measures so that the occurrence and resulting impacts are minimized. In order to study the pavement failure modes and to minimize them so as to get good serviceability from the huge road assets the country is having, the actual response of pavement structure needs to be monitored. This necessitates a systematic assessment and performance evaluation of pavement with known design and influencing factors. An array of response measuring instruments, under measurable loading conditions is required to accrue objective indicators. Evaluation strategies use performance monitoring through laboratory and field evaluation, while the field evaluation itself can be accomplished by monitoring in-service pavements or smaller replicated test strips using an "Accelerated Pavement Testing" protocol. CSIR-CRRI (Central Road Research Institute) has recently procured and established a national facility of Accelerated Pavement Testing. Through this, tire pressure can be simulated on the in-field loading on pavements, and design traffic. A systematic study was initiated on the permanent deformation development involving a flexible pavement designed as per Indian practice. The paper brings out the details of this evaluation study and also features the capabilities and applications of Indian APTF in the issue.
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paper_title: Road Roughness Limit Values Based on Measured Vehicle Vibration

paper_content:

AbstractThis study identified longitudinal road roughness limit values based on measured vibration induced in a road-vehicle-driver interaction system. The relations between measured vehicle vibration response and the international roughness index (IRI) were summarized. Frequency-weighted acceleration on the seat and dynamic load coefficient (DLC) were used to quantify ride comfort, ride safety, and the dynamic load of the vehicle and road. Linear relationship coefficients were identified or taken from references. The expected large range of vibration response root mean square (RMS) values was observed for the same level of IRI. IRI limit values were derived for chosen threshold values of vehicle vibration response as a function of vehicle velocity. Velocity-related IRI limit curves were proposed based on the fitting of IRI limit values lower envelope. IRI limit curves were compared with threshold proposals of other authors and width thresholds used in road maintenance. Some of the estimated IRI limit cur...
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paper_title: Roughness and roadway safety

paper_content:

Roughness can play a significant role in roadway accidents and should be considered when evaluating pavement safety as well as when planning and designing safety improvements. Roadway roughness can cause problems with steering, braking, maneuvering, and response that can lead to loss of vehicle control and can result in an accident. In addition, rough pavements can sometimes shake or bounce a vehicle so severely that it will lose part or all of the load it is carrying, which then leads to lost-load accidents. This paper discusses the magnitude of the various problems associated with vehicle performance on rough roads and the types of accidents and safety problems that result. The various individual parameters that cause roughness are examined and their overall effect on safety are prioritized. Examples of corrective actions and their benefits are discussed. In the future additional consideration should be given to this problem and to using safety funds to make rehabilitations that decrease roughness and improve the ride quality and safety of a highway. (Author)
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paper_title: POTENTIAL SAFETY COST-EFFECTIVENESS OF TREATING RUTTED PAVEMENTS

paper_content:

Pavement rutting is a problem that has unknown consequences from a safety-based point of view. It is assumed that the wheelpath fills with water in wet-weather situations, thus increasing the potential for a vehicle to hydroplane. A study was conducted to quantify how pavement rutting affects accident rates and to evaluate possible safety-based guidelines for the treatment of pavement rutting. Rut depth, traffic volumes, and accident databases maintained by the Wisconsin Department of Transportation for undivided rural highways were then analyzed to identify statistical trends and relationships. Accidents were categorized as rut-related if the prevailing conditions could be potentially associated with the occurrence of hydroplaning. Rut depth measurements were average values for both directions of 1.8-km (1.1-mi) segments and represent the average elevation difference between the tire paths and the high point between them. The results of the statistical analyses indicated that the defined rut-related accident rate begins to increase at a significantly greater rate as rut depths exceed 7.6 mm (0.3 in.). The cost-effectiveness of potential accident reductions associated with reductions in the relative amount of rutted pavement was also evaluated.
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paper_title: Road Roughness Limit Values Based on Measured Vehicle Vibration

paper_content:

AbstractThis study identified longitudinal road roughness limit values based on measured vibration induced in a road-vehicle-driver interaction system. The relations between measured vehicle vibration response and the international roughness index (IRI) were summarized. Frequency-weighted acceleration on the seat and dynamic load coefficient (DLC) were used to quantify ride comfort, ride safety, and the dynamic load of the vehicle and road. Linear relationship coefficients were identified or taken from references. The expected large range of vibration response root mean square (RMS) values was observed for the same level of IRI. IRI limit values were derived for chosen threshold values of vehicle vibration response as a function of vehicle velocity. Velocity-related IRI limit curves were proposed based on the fitting of IRI limit values lower envelope. IRI limit curves were compared with threshold proposals of other authors and width thresholds used in road maintenance. Some of the estimated IRI limit cur...
---
paper_title: Incorporating Road Safety into Pavement Management

paper_content:

Improving road safety through proper pavement engineering and maintenance should be one of the major objectives of pavement management systems. When pavements are evaluated in terms of safety, a number of factors related to pavement engineering properties are raised, such as pavement geometric design, paving materials and mix design, pavement surface properties, shoulder type, and pavement color and visibility. Each year there are voluminous annual reports on traffic accident statistics and discussions of such road safety issues as road safety modeling and pavement safety measurements and criteria. Although road safety may be considered a separate area, it should be incorporated into pavement management systems. The main pavement engineering relationships associated with road safety are identified, and the various aspects of road safety related to pavement management, such as pavement types, pavement surface macrotexture and microtexture, and pavement safety measurements, criteria, and evaluation methods, are discussed. A systematic approach is proposed for the coordination of pavement maintenance programs with road safety improvement and the incorporation or integration of safety management with pavement and other management systems. Finally, a list of possible remedial measures for road safety improvements associated with pavement maintenance activities is recommended.
---
paper_title: A review on automated pavement distress detection methods

paper_content:

In recent years, extensive research has been conducted on pavement distress detection. A large part of these studies applied automated methods to capture different distresses. In this paper, a literature review on the distresses and related detection methods are presented. This review also includes commercial solutions. Thereafter, a gap analysis is conducted which is concluded that in particular the distresses related to pavement micro-texture need serious additional research in order to be implemented in a cost-effective fashion. Depth-related distresses are detectible fairly well, but rely on expensive tools.
---
paper_title: Data collection technologies for road management

paper_content:

Different types of data are required for managing the road infrastructure. Inventory data describe the physical elements of a road system. Condition data describe the condition of elements that can be expected to change over time. There are a wide range of technologies available to the road manager for measuring attributes of the road network. The challenge is to select the appropriate equipment, given local conditions and the way in which the data are expected to be used. The purpose of this note is to give a general view of the currently available survey technologies applied to pavements, bridges and traffic. This includes an assessment of the applicability of these technologies in developing countries. The goal is to assist managers in establishing an appropriate and sustainable e data collection program and procuring the appropriate equipment to collect the data. This note is a summary of the report 'Data Collection Technologies for Road Management' (see report no. 37372). The note opens with a discussion of data collection requirements. This is then followed by separate discussions on pavements, bridges and traffic survey technologies. A cost/performance analysis between available equipment is presented in each section. Finally, recommendations for data collection are presented as a guidance to managers in developing countries.
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paper_title: Review and Analysis of Pothole Detection Methods

paper_content:

As one type of pavement distresses, potholes are important clues indicating structural defects of the asphalt road, and accurately detecting these potholes is one of important tasks for determining proper strategies of asphalt-surfaced pavement maintenance and rehabilitation. However, manually detecting and evaluating methods are expensive and timeconsuming. Thus, several efforts have been made for developing a technology which can automatically detect and recognize potholes, which may contribute to improvement of survey efficiency and pavement quality through prior investigation and immediate action. In this study, we investigate and analyze pothole detection methods which have developed and propose a potential direction of developing a pothole detection method to accurately and efficiently detect potholes.
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paper_title: Automatic Road Crack Detection and Characterization

paper_content:

A fully integrated system for the automatic detection and characterization of cracks in road flexible pavement surfaces, which does not require manually labeled samples, is proposed to minimize the human subjectivity resulting from traditional visual surveys. The first task addressed, i.e., crack detection, is based on a learning from samples paradigm, where a subset of the available image database is automatically selected and used for unsupervised training of the system. The system classifies nonoverlapping image blocks as either containing crack pixels or not. The second task deals with crack type characterization, for which another classification system is constructed, to characterize the detected cracks' connect components. Cracks are labeled according to the types defined in the Portuguese Distress Catalog, with each different crack present in a given image receiving the appropriate label. Moreover, a novel methodology for the assignment of crack severity levels is introduced, computing an estimate for the width of each detected crack. Experimental crack detection and characterization results are presented based on images captured during a visual road pavement surface survey over Portuguese roads, with promising results. This is shown by the quantitative evaluation methodology introduced for the evaluation of this type of system, including a comparison with human experts' manual labeling results.
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paper_title: CrackIT — An image processing toolbox for crack detection and characterization

paper_content:

This paper presents a comprehensive set of image processing algorithms for detection and characterization of road pavement surface crack distresses, which is being made available to the research community. The toolbox, in the Matlab environment, includes algorithms to preprocess images, to detect cracks and characterize them into types, based on image processing and pattern recognition techniques, as well as modules devoted to the performance evaluation of crack detection and characterization solutions. A sample database of 84 pavement surface images taken during a traditional road survey is provided with the toolbox, since no pavement image databases are publicly available for crack detection and characterization evaluation purposes. Results achieved applying the proposed toolbox to the sample database are discussed, illustrating the potential of the available algorithms.
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paper_title: Road pavement crack automatic detection by MMS images

paper_content:

The research topic was to test different feature extraction methods to localize road pavement cracks useful to construct a spatial database for the pavement distress monitoring. Several images were acquired by means of a line scan camera that assembled in a Mobile Mapping System (MMS) allows tracking directly the position of the images by a GPS-INS system. Following an automatic digital image processing was performed by means of several algorithms based on different approaches (edge detection and fuzzy set theory). The detected cracks were described with some parameters in relation to some shape characteristics (dimension, typology, direction), which are necessary to recognize the gravity of the road pavement conditions. The edge detection techniques tested in this research allowed identifying fatigue cracking or alligator cracking and also thin linear cracks in images with strong radiometric jumps by applying filters, gradient functions and morphological operators. The snake approach was one of them, in particular the type called Gradient Vector Flow (GVF). Another approach was based on the fuzzy theory. The advantage of this method is that the pixels, necessary to identify the cracks in road pavement, are darker than their surroundings in an image. The last stage was the pavement distress spatial database collection. The Mobile Mapping System (MMS) has allowed localizing the raster data and consequently the vector features of the detected cracks, associating into the table their attributes too. The proposed approaches allow to automatically localize and classify the kind of road pavement crack.
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paper_title: Pavement Raveling Detection and Measurement from Synchronized Intensity and Range Images

paper_content:

Raveling on asphalt surfaces is a loss of fine and coarse aggregates from the asphalt matrix. The severity of raveling can be an indicator of the state of pavements, as excessive raveling not only reduces the ride quality but eventually leads to pothole formation or cracking. Hence, raveling must be detected and quantified. In this study and for the first time, raveling was quantified from a combination of two- and three-dimensional images. First, a texture descriptor method called Laws’ texture energy measure was used in conjunction with Gabor filters and other morphological operations to distinguish road areas. Then, digital signal processing techniques were used to detect and to quantify raveling. Hundreds of images captured by an automated pavement surveying system were used to test and to show the promise of the proposed algorithm.
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paper_title: A Review of Three-Dimensional Imaging Technologies for Pavement Distress Detection and Measurements

paper_content:

With the ever-increasing emphasis on maintaining road assets to a high standard, the need for fast accurate inspection for road distresses is becoming extremely important. Surface distresses on roads are essentially three dimensional (3-D) in nature. Automated visual surveys are the best option available. However, the imaging conditions, in terms of lighting, etc., are very random. For example, the challenge of measuring the volume of the pothole requires a large field of view with a reasonable spatial resolution, whereas microtexture evaluation requires very accurate imaging. Within the two extremes, there is a range of situations that require 3-D imaging. Three-dimensional imaging consists of a number of techniques such as interferometry and depth from focus. Out of these, laser imagers are mainly used for road surface distress inspection. Many other techniques are relatively unknown among the transportation community, and industrial products are rare. The main impetus for this paper is derived from the rarity of 3-D industrial imagers that employ alternative techniques for use in transportation. In addition, the need for this work is also highlighted by a lack of literature that evaluates the relative merits/demerits of various imaging methods for different distress measurement situations in relation to pavements. This overview will create awareness of available 3-D imaging methods in order to help make a fast initial technology selection and deployment. The review is expected to be helpful for researchers, practicing engineers, and decision makers in transportation engineering.
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paper_title: Use of a Self-Organizing Map for Crack Detection in Highly Textured Pavement Images

paper_content:

AbstractA study on using an unsupervised learning technique, called a self-organizing map (SOM) or Kohonen map, for the detection of road cracks from pavement images is described in this paper. The main focus is on highly textured road images that make the crack detection very difficult. Road images are split into smaller rectangular cells, and a representative data set is generated for each cell by analyzing image texture and color properties. Texture and color properties are combined with a Kohonen map to distinguish crack areas from the background. Using this technique, cracks are detected to a precision of 77%. The algorithm also resulted in a recall of 73% despite the background having very strong visual texture. The technique applied here shows a great deal of promise despite the images being captured in an uncontrolled environment devoid of state-of-the-art image-acquisition setups. The results are also benchmarked against an advanced algorithm reported in a recent research paper. The benchmarking ...
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paper_title: Automatic Road Crack Detection and Characterization

paper_content:

A fully integrated system for the automatic detection and characterization of cracks in road flexible pavement surfaces, which does not require manually labeled samples, is proposed to minimize the human subjectivity resulting from traditional visual surveys. The first task addressed, i.e., crack detection, is based on a learning from samples paradigm, where a subset of the available image database is automatically selected and used for unsupervised training of the system. The system classifies nonoverlapping image blocks as either containing crack pixels or not. The second task deals with crack type characterization, for which another classification system is constructed, to characterize the detected cracks' connect components. Cracks are labeled according to the types defined in the Portuguese Distress Catalog, with each different crack present in a given image receiving the appropriate label. Moreover, a novel methodology for the assignment of crack severity levels is introduced, computing an estimate for the width of each detected crack. Experimental crack detection and characterization results are presented based on images captured during a visual road pavement surface survey over Portuguese roads, with promising results. This is shown by the quantitative evaluation methodology introduced for the evaluation of this type of system, including a comparison with human experts' manual labeling results.
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paper_title: Automatic Road Pavement Assessment with Image Processing: Review and Comparison

paper_content:

In the field of noninvasive sensing techniques for civil infrastructures monitoring, this paper addresses the problem of crack detection, in the surface of the French national roads, by automatic analysis of optical images. The first contribution is a state of the art of the image-processing tools applied to civil engineering. The second contribution is about fine-defect detection in pavement surface. The approach is based on a multi-scale extraction and a Markovian segmentation. Third, an evaluation and comparison protocol which has been designed for evaluating this difficult task—the road pavement crack detection—is introduced. Finally, the proposed method is validated, analysed, and compared to a detection approach based on morphological tools.
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paper_title: Procedure to Determine the Geometry of Road Alignment Using GPS Data

paper_content:

Traffic safety and road geometry are strictly interlinked because road geometry deeply influences the drivers’ performance. So it is very important to know road alignments geometry. Road centreline data for the geometry definition can be generally collected from existing maps or by static measurements (traditional surveys) or by dynamic measurements (GPS receiver mounted on a car). The procedure to define the road geometry, independently from the survey technique and the data type, must be implemented considering the precision level necessary to road applications. This study tries to define intrinsic limits of this integrated data measurement and processing procedure, with the aim to define the reliability of road alignment geometry according to the final employing of road geometry recognition.
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paper_title: CrackIT — An image processing toolbox for crack detection and characterization

paper_content:

This paper presents a comprehensive set of image processing algorithms for detection and characterization of road pavement surface crack distresses, which is being made available to the research community. The toolbox, in the Matlab environment, includes algorithms to preprocess images, to detect cracks and characterize them into types, based on image processing and pattern recognition techniques, as well as modules devoted to the performance evaluation of crack detection and characterization solutions. A sample database of 84 pavement surface images taken during a traditional road survey is provided with the toolbox, since no pavement image databases are publicly available for crack detection and characterization evaluation purposes. Results achieved applying the proposed toolbox to the sample database are discussed, illustrating the potential of the available algorithms.
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paper_title: Crack detection using image processing: A critical review and analysis

paper_content:

Abstract Cracks on the concrete surface are one of the earliest indications of degradation of the structure which is critical for the maintenance as well the continuous exposure will lead to the severe damage to the environment. Manual inspection is the acclaimed method for the crack inspection. In the manual inspection, the sketch of the crack is prepared manually, and the conditions of the irregularities are noted. Since the manual approach completely depends on the specialist’s knowledge and experience, it lacks objectivity in the quantitative analysis. So, automatic image-based crack detection is proposed as a replacement. Literature presents different techniques to automatically identify the crack and its depth using image processing techniques. In this research, a detailed survey is conducted to identify the research challenges and the achievements till in this field. Accordingly, 50 research papers are taken related to crack detection, and those research papers are reviewed. Based on the review, analysis is provided based on the image processing techniques, objectives, accuracy level, error level, and the image data sets. Finally, we present the various research issues which can be useful for the researchers to accomplish further research on the crack detection.
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paper_title: Characterizing Pavement Surface Distress Conditions with Hyper-Spatial Resolution Natural Color Aerial Photography

paper_content:

Roadway pavement surface distress information is critical for effective pavement asset management, and subsequently, transportation management agencies at all levels (i.e., federal, state, and local) dedicate a large amount of time and money to routinely evaluate pavement surface distress conditions as the core of their asset management programs. However, currently adopted ground-based evaluation methods for pavement surface conditions have many disadvantages, like being time-consuming and expensive. Aircraft-based evaluation methods, although getting more attention, have not been used for any operational evaluation programs yet because the acquired images lack the spatial resolution to resolve finer scale pavement surface distresses. Hyper-spatial resolution natural color aerial photography (HSR-AP) provides a potential method for collecting pavement surface distress information that can supplement or substitute for currently adopted evaluation methods. Using roadway pavement sections located in the State of New Mexico as an example, this research explored the utility of aerial triangulation (AT) technique and HSR-AP acquired from a low-altitude and low-cost small-unmanned aircraft system (S-UAS), in this case a tethered helium weather balloon, to permit characterization of detailed pavement surface distress conditions. The Wilcoxon Signed Rank test, Mann-Whitney U test, and visual comparison were used to compare detailed pavement surface distress rates measured from HSR-AP derived products (orthophotos and digital surface models generated from AT) with reference distress rates manually collected on the ground using standard protocols. The results reveal that S-UAS based hyper-spatial resolution imaging and AT techniques can provide detailed and reliable primary observations suitable for characterizing detailed pavement surface distress conditions comparable to the ground-based manual measurement, which lays the foundation for the future application of HSR-AP for automated detection and assessment of detailed pavement surface distress conditions.
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paper_title: Road pavement crack automatic detection by MMS images

paper_content:

The research topic was to test different feature extraction methods to localize road pavement cracks useful to construct a spatial database for the pavement distress monitoring. Several images were acquired by means of a line scan camera that assembled in a Mobile Mapping System (MMS) allows tracking directly the position of the images by a GPS-INS system. Following an automatic digital image processing was performed by means of several algorithms based on different approaches (edge detection and fuzzy set theory). The detected cracks were described with some parameters in relation to some shape characteristics (dimension, typology, direction), which are necessary to recognize the gravity of the road pavement conditions. The edge detection techniques tested in this research allowed identifying fatigue cracking or alligator cracking and also thin linear cracks in images with strong radiometric jumps by applying filters, gradient functions and morphological operators. The snake approach was one of them, in particular the type called Gradient Vector Flow (GVF). Another approach was based on the fuzzy theory. The advantage of this method is that the pixels, necessary to identify the cracks in road pavement, are darker than their surroundings in an image. The last stage was the pavement distress spatial database collection. The Mobile Mapping System (MMS) has allowed localizing the raster data and consequently the vector features of the detected cracks, associating into the table their attributes too. The proposed approaches allow to automatically localize and classify the kind of road pavement crack.
---
paper_title: Pavement Raveling Detection and Measurement from Synchronized Intensity and Range Images

paper_content:

Raveling on asphalt surfaces is a loss of fine and coarse aggregates from the asphalt matrix. The severity of raveling can be an indicator of the state of pavements, as excessive raveling not only reduces the ride quality but eventually leads to pothole formation or cracking. Hence, raveling must be detected and quantified. In this study and for the first time, raveling was quantified from a combination of two- and three-dimensional images. First, a texture descriptor method called Laws’ texture energy measure was used in conjunction with Gabor filters and other morphological operations to distinguish road areas. Then, digital signal processing techniques were used to detect and to quantify raveling. Hundreds of images captured by an automated pavement surveying system were used to test and to show the promise of the proposed algorithm.
---
paper_title: Critical Assessment of Detecting Asphalt Pavement Cracks under Different Lighting and Low Intensity Contrast Conditions Using Emerging 3D Laser Technology

paper_content:

AbstractAfter decades of research and development, a fully automated system for pavement crack detection with an intensity-based two-dimensional (2D) imaging data acquisition system under different lighting and low intensity contrast conditions still remains a challenge. With the advances of sensor technology, a three-dimensional (3D) laser technology that can collect high-resolution 3D continuous transverse pavement profiles for detecting cracks on the basis of their 3D elevation rather than 2D intensity has become available. This study, sponsored by the U.S. Department of Transportation (US DOT) Research Innovative Technology Administration (RITA) program, evaluates the feasibility of using emerging 3D laser technology to detect cracks under different lighting and poor intensity contrast conditions. For this purpose, 3D surface data from laboratory tests on cracks ranging from 1 to 5mm wide and tests on the actual pavement cracks of different widths and depths and under different lighting conditions wer...
---
paper_title: Use of a Self-Organizing Map for Crack Detection in Highly Textured Pavement Images

paper_content:

AbstractA study on using an unsupervised learning technique, called a self-organizing map (SOM) or Kohonen map, for the detection of road cracks from pavement images is described in this paper. The main focus is on highly textured road images that make the crack detection very difficult. Road images are split into smaller rectangular cells, and a representative data set is generated for each cell by analyzing image texture and color properties. Texture and color properties are combined with a Kohonen map to distinguish crack areas from the background. Using this technique, cracks are detected to a precision of 77%. The algorithm also resulted in a recall of 73% despite the background having very strong visual texture. The technique applied here shows a great deal of promise despite the images being captured in an uncontrolled environment devoid of state-of-the-art image-acquisition setups. The results are also benchmarked against an advanced algorithm reported in a recent research paper. The benchmarking ...
---
paper_title: MaNIAC-UAV - a methodology for automatic pavement defects detection using images obtained by Unmanned Aerial Vehicles

paper_content:

Intelligent Transportation Systems - ITS is a set of integrated technologies (Remote Sensing, Image Processing, Communications Systems and others) that aim to offer services and advanced traffic management for the several transportation modes (road, air and rail). Collect data on the characteristics and conditions of the road surface and keep them update is an important and difficult task that needs to be currently managed in order to reduce accidents and vehicle maintenance costs. Nowadays several roads and highways are paved, but usually there is insufficient updated data about current condition and status. There are different types of pavement defects on the roads and to keep them in good condition they should be constantly monitored and maintained according to pavement management strategy. This paper presents a methodology to obtain, automatically, information about the conditions of the highway asphalt pavement. Data collection was done through remote sensing using an UAV (Unmanned Aerial Vehicle) and the image processing and pattern recognition techniques through Geographic Information System.
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paper_title: Road crack detection using color variance distribution and discriminant analysis for approaching smooth vehicle movement on non-smooth roads

paper_content:

We present an image analysis based automatic road crack detection method for conducting smooth driving on non-smooth road surfaces. In the new proposal, first the road surface areas which include cracks are extracted as crack images by analyzing the color variance on norm. Then cracks are extracted from those areas by introducing a method on discriminant analysis. According to experiments using the images of different road surfaces, the new proposal showed better performances than the conventional approaches.
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paper_title: Adaptive Road Crack Detection System by Pavement Classification

paper_content:

This paper presents a road distress detection system involving the phases needed to properly deal with fully automatic road distress assessment. A vehicle equipped with line scan cameras, laser illumination and acquisition HW-SW is used to storage the digital images that will be further processed to identify road cracks. Pre-processing is firstly carried out to both smooth the texture and enhance the linear features. Non-crack features detection is then applied to mask areas of the images with joints, sealed cracks and white painting, that usually generate false positive cracking. A seed-based approach is proposed to deal with road crack detection, combining Multiple Directional Non-Minimum Suppression (MDNMS) with a symmetry check. Seeds are linked by computing the paths with the lowest cost that meet the symmetry restrictions. The whole detection process involves the use of several parameters. A correct setting becomes essential to get optimal results without manual intervention. A fully automatic approach by means of a linear SVM-based classifier ensemble able to distinguish between up to 10 different types of pavement that appear in the Spanish roads is proposed. The optimal feature vector includes different texture-based features. The parameters are then tuned depending on the output provided by the classifier. Regarding non-crack features detection, results show that the introduction of such module reduces the impact of false positives due to non-crack features up to a factor of 2. In addition, the observed performance of the crack detection system is significantly boosted by adapting the parameters to the type of pavement.
---
paper_title: A review on automated pavement distress detection methods

paper_content:

In recent years, extensive research has been conducted on pavement distress detection. A large part of these studies applied automated methods to capture different distresses. In this paper, a literature review on the distresses and related detection methods are presented. This review also includes commercial solutions. Thereafter, a gap analysis is conducted which is concluded that in particular the distresses related to pavement micro-texture need serious additional research in order to be implemented in a cost-effective fashion. Depth-related distresses are detectible fairly well, but rely on expensive tools.
---
paper_title: A Simplified Computer Vision System for Road Surface Inspection and Maintenance

paper_content:

This paper presents a computer vision system whose aim is to detect and classify cracks on road surfaces. Most of the previous works consisted of complex and expensive acquisition systems, whereas we have developed a simpler one composed by a single camera mounted on a light truck and no additional illumination. The system also includes tracking devices in order to geolocalize the captured images. The computer vision algorithm has three steps: hard shoulder detection, cell candidate proposal, and crack classification. First the region of interest (ROI) is delimited using the Hough transform (HT) to detect the hard shoulders. The cell candidate step is divided into two substeps: Hough transform features (HTF) and local binary pattern (LBP). Both of them split up the image into nonoverlapping small grid cells and also extract edge orientation and texture features, respectively. At the fusion stage, the detection is completed by mixing those techniques and obtaining the crack seeds. Afterward, their shape is improved using a new developed morphology operator. Finally, one classification based on the orientation of the detected lines has been applied following the Chain code. Massive experiments were performed on several stretches on a Spanish road showing very good performance.
---
paper_title: A Review of Three-Dimensional Imaging Technologies for Pavement Distress Detection and Measurements

paper_content:

With the ever-increasing emphasis on maintaining road assets to a high standard, the need for fast accurate inspection for road distresses is becoming extremely important. Surface distresses on roads are essentially three dimensional (3-D) in nature. Automated visual surveys are the best option available. However, the imaging conditions, in terms of lighting, etc., are very random. For example, the challenge of measuring the volume of the pothole requires a large field of view with a reasonable spatial resolution, whereas microtexture evaluation requires very accurate imaging. Within the two extremes, there is a range of situations that require 3-D imaging. Three-dimensional imaging consists of a number of techniques such as interferometry and depth from focus. Out of these, laser imagers are mainly used for road surface distress inspection. Many other techniques are relatively unknown among the transportation community, and industrial products are rare. The main impetus for this paper is derived from the rarity of 3-D industrial imagers that employ alternative techniques for use in transportation. In addition, the need for this work is also highlighted by a lack of literature that evaluates the relative merits/demerits of various imaging methods for different distress measurement situations in relation to pavements. This overview will create awareness of available 3-D imaging methods in order to help make a fast initial technology selection and deployment. The review is expected to be helpful for researchers, practicing engineers, and decision makers in transportation engineering.
---
paper_title: Automated Imaging Technologies for Pavement Distress Surveys

paper_content:

This circular documents state-of-the-art techniques and technologies in the acquisition of pavement surface images, and basic requirements needed to automatically identify and classify pavement surface distresses. The basics of film or magnetic tape–based image acquisition are presented. The circular also discusses digital acquisition and reports on the new laser-based imaging system with its high-quality image and low-power usage, as well as the potential for using 3-D laser imaging technology for pavement surveys.
---
paper_title: Pavement cracking measurements using 3D laser-scan images

paper_content:

Pavement condition surveying is vital for pavement maintenance programs that ensure ride quality and traffic safety. This paper first introduces an automated pavement inspection system which uses a three-dimensional (3D) camera and a structured laser light to acquire dense transverse profiles of a pavement lane surface when it carries a moving vehicle. After the calibration, the 3D system can yield a depth resolution of 0.5 mm and a transverse resolution of 1.56 mm pixel−1 at 1.4 m camera height from the ground. The scanning rate of the camera can be set to its maximum at 5000 lines s−1, allowing the density of scanned profiles to vary with the vehicle's speed. The paper then illustrates the algorithms that utilize 3D information to detect pavement distress, such as transverse, longitudinal and alligator cracking, and presents the field tests on the system's repeatability when scanning a sample pavement in multiple runs at the same vehicle speed, at different vehicle speeds and under different weather conditions. The results show that this dedicated 3D system can capture accurate pavement images that detail surface distress, and obtain consistent crack measurements in repeated tests and under different driving and lighting conditions.
---
paper_title: A review on automated pavement distress detection methods

paper_content:

In recent years, extensive research has been conducted on pavement distress detection. A large part of these studies applied automated methods to capture different distresses. In this paper, a literature review on the distresses and related detection methods are presented. This review also includes commercial solutions. Thereafter, a gap analysis is conducted which is concluded that in particular the distresses related to pavement micro-texture need serious additional research in order to be implemented in a cost-effective fashion. Depth-related distresses are detectible fairly well, but rely on expensive tools.
---
paper_title: Pavement Raveling Detection and Measurement from Synchronized Intensity and Range Images

paper_content:

Raveling on asphalt surfaces is a loss of fine and coarse aggregates from the asphalt matrix. The severity of raveling can be an indicator of the state of pavements, as excessive raveling not only reduces the ride quality but eventually leads to pothole formation or cracking. Hence, raveling must be detected and quantified. In this study and for the first time, raveling was quantified from a combination of two- and three-dimensional images. First, a texture descriptor method called Laws’ texture energy measure was used in conjunction with Gabor filters and other morphological operations to distinguish road areas. Then, digital signal processing techniques were used to detect and to quantify raveling. Hundreds of images captured by an automated pavement surveying system were used to test and to show the promise of the proposed algorithm.
---
paper_title: Critical Assessment of Detecting Asphalt Pavement Cracks under Different Lighting and Low Intensity Contrast Conditions Using Emerging 3D Laser Technology

paper_content:

AbstractAfter decades of research and development, a fully automated system for pavement crack detection with an intensity-based two-dimensional (2D) imaging data acquisition system under different lighting and low intensity contrast conditions still remains a challenge. With the advances of sensor technology, a three-dimensional (3D) laser technology that can collect high-resolution 3D continuous transverse pavement profiles for detecting cracks on the basis of their 3D elevation rather than 2D intensity has become available. This study, sponsored by the U.S. Department of Transportation (US DOT) Research Innovative Technology Administration (RITA) program, evaluates the feasibility of using emerging 3D laser technology to detect cracks under different lighting and poor intensity contrast conditions. For this purpose, 3D surface data from laboratory tests on cracks ranging from 1 to 5mm wide and tests on the actual pavement cracks of different widths and depths and under different lighting conditions wer...
---
paper_title: A Review of Three-Dimensional Imaging Technologies for Pavement Distress Detection and Measurements

paper_content:

With the ever-increasing emphasis on maintaining road assets to a high standard, the need for fast accurate inspection for road distresses is becoming extremely important. Surface distresses on roads are essentially three dimensional (3-D) in nature. Automated visual surveys are the best option available. However, the imaging conditions, in terms of lighting, etc., are very random. For example, the challenge of measuring the volume of the pothole requires a large field of view with a reasonable spatial resolution, whereas microtexture evaluation requires very accurate imaging. Within the two extremes, there is a range of situations that require 3-D imaging. Three-dimensional imaging consists of a number of techniques such as interferometry and depth from focus. Out of these, laser imagers are mainly used for road surface distress inspection. Many other techniques are relatively unknown among the transportation community, and industrial products are rare. The main impetus for this paper is derived from the rarity of 3-D industrial imagers that employ alternative techniques for use in transportation. In addition, the need for this work is also highlighted by a lack of literature that evaluates the relative merits/demerits of various imaging methods for different distress measurement situations in relation to pavements. This overview will create awareness of available 3-D imaging methods in order to help make a fast initial technology selection and deployment. The review is expected to be helpful for researchers, practicing engineers, and decision makers in transportation engineering.
---
paper_title: Use of a Self-Organizing Map for Crack Detection in Highly Textured Pavement Images

paper_content:

AbstractA study on using an unsupervised learning technique, called a self-organizing map (SOM) or Kohonen map, for the detection of road cracks from pavement images is described in this paper. The main focus is on highly textured road images that make the crack detection very difficult. Road images are split into smaller rectangular cells, and a representative data set is generated for each cell by analyzing image texture and color properties. Texture and color properties are combined with a Kohonen map to distinguish crack areas from the background. Using this technique, cracks are detected to a precision of 77%. The algorithm also resulted in a recall of 73% despite the background having very strong visual texture. The technique applied here shows a great deal of promise despite the images being captured in an uncontrolled environment devoid of state-of-the-art image-acquisition setups. The results are also benchmarked against an advanced algorithm reported in a recent research paper. The benchmarking ...
---
paper_title: Road crack detection using color variance distribution and discriminant analysis for approaching smooth vehicle movement on non-smooth roads

paper_content:

We present an image analysis based automatic road crack detection method for conducting smooth driving on non-smooth road surfaces. In the new proposal, first the road surface areas which include cracks are extracted as crack images by analyzing the color variance on norm. Then cracks are extracted from those areas by introducing a method on discriminant analysis. According to experiments using the images of different road surfaces, the new proposal showed better performances than the conventional approaches.
---
paper_title: Automated Imaging Technologies for Pavement Distress Surveys

paper_content:

This circular documents state-of-the-art techniques and technologies in the acquisition of pavement surface images, and basic requirements needed to automatically identify and classify pavement surface distresses. The basics of film or magnetic tape–based image acquisition are presented. The circular also discusses digital acquisition and reports on the new laser-based imaging system with its high-quality image and low-power usage, as well as the potential for using 3-D laser imaging technology for pavement surveys.
---
paper_title: Terrestrial laser scanner for the analysis of airport pavement geometry

paper_content:

AbstractThe knowledge of the geometric features of an airport’s pavement surface is essential to ensuring the safety and comfort of the driving users. For this purpose, it is important to find the most suitable survey methods and computation procedures for determining these geometric features and their evolution over time. In this study, we used a terrestrial laser scanner (TLS) to survey a stretch of a taxiway of an international airport. We designed the survey with the goal of defining the optimal parameters for the scans and the spacing between the TLS station points, combining high efficiency with data quality and accuracy. An algorithm for the semi-automatic extraction of the longitudinal and transversal profiles of the track from the digital elevation model (DEM) has been implemented. Longitudinal and cross slopes have been computed from the profiles using a linear fit, assessing the conformity of the values to the standards. The algorithm allows the verification of irregularities and the assessment...
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paper_title: Use of Terrestrial Laser Scanner for Rigid Airport Pavement Management

paper_content:

The evaluation of the structural efficiency of airport infrastructures is a complex task. Faulting is one of the most important indicators of rigid pavement performance. The aim of our study is to provide a new method for faulting detection and computation on jointed concrete pavements. Nowadays, the assessment of faulting is performed with the use of laborious and time-consuming measurements that strongly hinder aircraft traffic. We proposed a field procedure for Terrestrial Laser Scanner data acquisition and a computation flow chart in order to identify and quantify the fault size at each joint of apron slabs. The total point cloud has been used to compute the least square plane fitting those points. The best-fit plane for each slab has been computed too. The attitude of each slab plane with respect to both the adjacent ones and the apron reference plane has been determined by the normal vectors to the surfaces. Faulting has been evaluated as the difference in elevation between the slab planes along chosen sections. For a more accurate evaluation of the faulting value, we have then considered a few strips of data covering rectangular areas of different sizes across the joints. The accuracy of the estimated quantities has been computed too.
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paper_title: AN AUTOMATED ROAD ROUGHNESS DETECTION FROM MOBILE LASER SCANNING DATA

paper_content:

Abstract. Rough roads influence the safety of the road users as accident rate increases with increasing unevenness of the road surface. Road roughness regions are required to be efficiently detected and located in order to ensure their maintenance. Mobile Laser Scanning (MLS) systems provide a rapid and cost-effective alternative by providing accurate and dense point cloud data along route corridor. In this paper, an automated algorithm is presented for detecting road roughness from MLS data. The presented algorithm is based on interpolating smooth intensity raster surface from LiDAR point cloud data using point thinning process. The interpolated surface is further processed using morphological and multi-level Otsu thresholding operations to identify candidate road roughness regions. The candidate regions are finally filtered based on spatial density and standard deviation of elevation criteria to detect the roughness along the road surface. The test results of road roughness detection algorithm on two road sections are presented. The developed approach can be used to provide comprehensive information to road authorities in order to schedule maintenance and ensure maximum safety conditions for road users.
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paper_title: Improving MMS Performance during Infrastructure Surveys through Geometry Aided Design

paper_content:

A Mobile Mapping System (MMS) equipped with laser scanners can collect large volumes of LiDAR data in a short time frame and generate complex 3D models of infrastructure. The performance of the automated algorithms that are developed to extract the infrastructure elements from the point clouds and create these models are largely dependent on the number of pulses striking infrastructure in these clouds. Mobile Mapping Systems have evolved accordingly, adding more and higher specification scanners to achieve the required high point density, however an unanswered question is whether optimising system configuration can achieve similar improvements at no extra cost. This paper presents an approach for improving MMS performance for infrastructure surveys through consideration of scanner orientation, scanner position and scanner operating parameters in a methodology referred to as Geometry Aided Design. A series of tests were designed to measure point cloud characteristics such as point density, point spacing and profile spacing. Three hypothetical MMSs were benchmarked to demonstrate the benefit of Geometry Aided Design for infrastructure surveys. These tests demonstrate that, with the recommended scanner configuration, a MMS, operating one high specification scanner and one low specification scanner, is capable of comparable performance with two high-end systems when benchmarked against a selection of planar, multi-faced and cylindrical targets, resulting in point density improvements in some cases of up to 400%.
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Title: Pavement Distress Detection Methods: A Review
Section 1: Introduction
Description 1: Write an overview of the importance of road conditions, challenges in pavement maintenance, and the role of Pavement Management Systems.

Section 2: State of Practice in Pavement Distress Classification and Related Indices
Description 2: Discuss current methods for pavement distress labeling and quantification, the lack of standardization, and various indices used for pavement management.

Section 3: Distress
Description 3: Explain the focus of the review on flexible pavement distresses and categorize them into families, emphasizing their impact on safety and comfort.

Section 4: Cracking Group
Description 4: Describe different types of pavement cracks, their causes, and effects on road safety and comfort.

Section 5: Viscoplastic Deformation Group
Description 5: Explain various viscoplastic deformations and their impact on pavement structure and vehicle safety.

Section 6: Surface Defect Group
Description 6: Discuss surface defects such as bleeding, polish aggregate, and raveling, along with their causes and identification characteristics.

Section 7: Miscellaneous Distress
Description 7: Detail other common distress types like patching, utility cuts, and manholes, and their impact on urban road conditions.

Section 8: Indices Review
Description 8: Review different pavement condition indices such as PCI, IRI, RD, and PSI, and discuss their applications and limitations.

Section 9: Method of Distress Classification Based on Comfort and Safety
Description 9: Propose a framework for classifying distresses based on their impact on safety and comfort and suggest appropriate technologies for distress detection.

Section 10: State of Art in Distress Detection
Description 10: Provide an overview of current and emerging technologies in pavement distress detection, including their precision, accuracy, and cost implications.

Section 11: Results
Description 11: Summarize the findings of the review, evaluate the effectiveness of different technologies in distress detection, and their suitability for various types of distresses.

Section 12: Conclusions
Description 12: Conclude with the importance of proactive pavement management, the necessity of appropriate distress detection technologies, and recommendations for future research.