Good afternoon everybody and you're very welcome to this webinar being conducted on behalf of the Institute for International European Affairs in Dublin. I'm delighted that our guest today is Dr Andrew McCormick who is a former director general of international relations and the lead official on Brexit for the Northern Ireland Executive, a post which he took up after a very distinguished career in the Northern Ireland civil service. Andrew will speak for about 20 minutes or thereabouts and then he'll take questions and answers and we'll finish about about four. The whole session, both the initial chat and the question and answer are on the record and please feel free to ask your questions via the Zoom platform and we'll get to them after Andrew's initial presentation. Andrew you're very welcome. Many thanks indeed. It's very good to be the host. I'm very grateful to IIEA for this opportunity. There's been so much comment, many events on the Windsor framework and in the very short space of time it's been around and I'm just very privileged to have this opportunity to contribute and I hope that we'll have an interesting discussion when we're into the Q&A phase. So just by way of outset, the framework achieves a delicate balance in both practical and constitutional terms. It's quite a big if it's applied as it's written and the hope and expectation is that it will lead to de-dramatisation, to borrow a word that's got a bit of history in the Brexit debate. That's the hope that there'll be a settling down into a new stability and I think so many people especially businesses in Northern Ireland and elsewhere need stability and certainty rather than any new tensions. So I'm not intending to do a detailed legal analysis. Others have done that. I want to just stay hopefully mainly at the big picture level looking at the thing in three sections. A little bit about the practical issues around the movement of goods which are at the heart of the issue. Just briefly on the competition issues but probably take a bit longer on the whole question around sovereignty and democratic deficit and all of that given the extent of attention that there's been on that. Just important just to start remembering that there's been so many horror stories talked about why on earth should there be restrictions on this or that be it plants or soil or pets or whatever in relation between GB&NI and the short answer is and was well it's because the land border is open. That's the choice that has been made and whatever the origin of that issue. I can't be any doubt that keeping the land border open is a good thing that any attempt to do anything else would have extremely serious consequences. Whatever may be said otherwise about that. In 2019 the approach agreed in the withdrawal agreement was very simplistic. It was the full application of EU law. The breakthrough that is now represented and it's been a journey towards this. It's not come all of a sudden is to adopt a risk-based approach. Now that takes us into complexity and compromise and that's therefore difficult. It's why the fine print and fine detail of all of this needs to be understood but that has a far better chance of leading to a stable and meaningful way forward. So just on movement of goods and all those issues. The Windsor framework enables a wider scope for the green land and red land idea than I thought possible. I do claim to have originated that five years ago and there's reports and evidence of that. I didn't see then or even up to quite recently how agri food goods could be included in that concept in the green lane and what I was told originally went back in October of 2017 about the EU's zero tolerance for risk on plant and animal health related issues. That's being mitigated by a combination of information requirements, labelling and there is an important reference in the EU fact sheet to green lane agri food goods continuing to comply with EU standards. I think that's quite an important point. Certainly the balance of opening things up in a very significant way while still having proportionate and adequate protections for the single market. That's why it's so complicated and detailed but the two sides seem to have settled that that is possible and that's very important. The compromises on parcels, on pets, on medicines are very important and are at the level of practical operation so again I'm not going to go into detail on those of their significant improvements. The wider issue of at risk goods as referred to in the protocol clarification and improvement of how that works that's very very important. It's been one of the trouble spots ever since the internal market bill of 2020. Second phase then just to talk a little bit about the competition issues. Again all logical and necessary from an EU point of view if you're going to have non-violent participation in the EU single market the change that's come about on state aid is mainly a clarification of what reach back means. The need for demonstration of a material impact on risk to competition and that's helpful again given that that was such a central issue throughout the whole main negotiations between the UK and the EU on what led to the trade and cooperation agreement. The level playing field all those concepts are so important. Similarly on VAT there's compromise on some details but still important elements of protection for the EU against distortions of trade so again those are they represent logical and reasonable compromises so at that level all of those things look remarkably sensible and you know I certainly struggle to see material ways to move on what's been agreed. A lot of the emotion in all of this is about sovereignty and of course even the things we've talked about already can be looked at through a sovereignty lens if you like but just going back to first principles this actually came up in quite an interesting discussion about that yesterday in the constitution committee of the Scottish Parliament where issues around sovereignty were being discussed in the context of regulatory divergence from within the UK but in principle you know all sovereign nations maybe except North Korea they share sovereignty in many ways on the basis of judgments about their self-interest so it's inclaimed that no other country would tolerate the position that applies to Northern Ireland under the withdrawal agreement well that's just drilling for that a little bit. The position arises as a result of a sovereign decision by the UK Parliament in 2020 which reflected the withdrawal agreement in the Conservative Manifesto. The facts of what was being entered into were known they were maybe denied, distorted or downplayed by the British government at that time which remains a very serious issue but Parliament if Parliament is sovereign it had the right to approve the withdrawal agreement. Secondly the protocol had the majority the support of a majority of elected representatives in Northern Ireland so the argument that consent was not given before a constitutional change is quite weak and inextremists could have been tested by a referendum I'm not sure that's been talked about all that much because it's a difficult thing to do I just wonder how unions would react to if there had been a referendum and support by the population for the protocol so just important to think about these things in the context of the constitutional settlement that is represented by the Belfast Good Friday agreement just then on being a rule taker well the EEA countries are in different respects in different ways their differences of detail but in principle they've made a sovereign choice to align to single market rules without the power of decision over those rules because as they judged as democratic institutions this was in their interests there are three important differences that apply first of all Northern Ireland does not pay into the EU budget the other countries have not only rule taking relationship with the single market but they pay for the privilege second point is that the four freedoms in relation to the single market aren't being applied in Northern Ireland especially freedom of movement was probably one of the most controversial issues throughout the whole of the Brexit debate and Northern Ireland has uniquely participation in the single market without the obligation to accept free movement of Labour and what we were told back in the early stages of our engagement as the Northern Ireland civil service with the EU post-Brek post that referendum we were told that Northern Ireland was just about small enough for exceptional treatment to be granted and that's I think an important point it certainly was an important point of my mind going to Edinburgh quite like quite a lot of what we've got the other third point that's different of course is that Northern Ireland is a region rather than a country so while from Norway the choice is simple they have the choice between staying in dynamic alignment or in extremist losing their participation in the single market so that's our it's a straightforward choice for Northern Ireland as a region of the UK the issues are potentially more invidious it might be which market to stay allowed to and that's why this does require much more thoughtful and detailed analysis and why I think it's worth pulling into stone and break and what all that all means there's been very good and detailed analysis presented by Jess Sargent from IFG by Sam and I sure would call on Murray and others that they've done super work in analysing all the tests stages and criteria stepping stepping back from that detail does seem to me that we're looking at what I would call a cliff edge risk uh if you speaking as a as a you know sometime occasional hill walker or cliff walker you walk too close to the edge the consequences can be catastrophic if you walk a reasonable distance away from the edge the risk is negligible so that just affects a perspective on this and behaviour and I would also have to say I think I think the whole issue is probably harder in theory in the abstract than it will be in practice I would be surprised if most of what happens looking ahead on the evolution of regulatory alignment most of the changes will be technical and uncontroversial and obviously a lot depends on how the UK perceives these things and what serves their self-interest even with the freedoms they have under the trade and cooperation agreement to diverge which was obviously what they would regard Brexit as being all about so just thinking about those scenarios and the flow diagrams there there's been some brilliant work done I think cutting to the end point potentially difficult point that arises would be if after all tests and hurdles and consultations and negotiations that are referred to and in a highly exceptional case what happens if something arises which can't be resolved and paragraph 64 of the UK command paper and some of the Secretary of State's comments would suggest that there's a need for frost community vote in the Nile Assembly to adopt positively a change that's emerged which has been put to the test in this process now when I first thought about that thought well well hold on a moment how can it be democratic for a minority in Northern Ireland to prevent something that a majority might favour because you could have a whole philosophical debate about majority rights as well as minority rights that's one of the books on my shelves that actually addresses that question it's fascinating and is that I think in fairness though we should only reach that point if all the tests have been applied and so we are looking at something which has material impact have significant effect on the at least the perception if not the reality of the of Northern Ireland's place in the UK but it's also will only arise if it's essential for ongoing participation in the single market otherwise the risk of retaliation or consequences would not arise so I go back to 1992 and I would add a small part in the work alongside the Mayhew talks on the design of the Strangerman institutions the question we always looked at in that context was what's the default what happens you can design all sorts of elaborate processes what if there's no agreement what applies and what we adopted and this actually does is hardwired into the decision making and with the executive in the assembly under the good Friday agreement standard answer is that if there's no agreement the status quo remains so on the one hand it can be argued that in first principles that where a major concern rises storm and break is invoked then correctly cross community agreement should be required to complete the change I think the alternative the other other way could be put maybe the question is whether the status quo which should be the default is that the precise set of regulations that has apply on one hand or is it the principle of dynamic alignment with the single market and that it seems to me there's still scope for debate as to as to which way to look at it and I don't have a technical answer to that I think that's something that really needs further debate and the even paragraph 64 I mentioned was a need for detail on this to emerge and be brought through the parliamentary process I just wonder if it might be better for the first vote at the level of principle which is scheduled for next year the vote on consent as originally provided for in the protocol might be better for that to happen before any particular test arises maybe that's a natural thing anyway because the hurdles that apply to the storm and break that's just I think that's that's where things are interesting and if the approach that the UK seems to be proposing is adopted then consequences the reason I describe this as a cliff edge no if it takes us back to looking at the whole debate as to how to manage an open land border without sufficient protection for the single market then that's a big issue it's not a new point in that it could have arisen under the original protocol under the provisions in relation to new EU law where agreement in the joint committee was required but the storm break widens the scope for that and opens up that possibility and I would have to say I think this not likely to much appetite for coming back to those issues in whatever town might be so far better to see if we can stabilize and get to something which is certain and stable for going for the position going forward and all of that supposes and I think there's very good reason to expect this is detailed and sincere on behalf of both the UK and the EU that this is a genuine agreement and there was a lot of discussion on the retained EU law bill yesterday in Scotland the phrase was used this is performative government and it's about the ideology of being seen to be different as opposed to the practical application of difference for which there's a respectable reasonable case so I think we everyone should be aware of the risk of mischief I'm sincerely hoping that that's not the case but I think it's important not to not to ruin that possibility and to be wary of it so stepping back really just to conclude on the total picture I do think it's a bit hyperbolic to say that dual market access is the best of both worlds that was a an unwise phrase I probably fell into the trap of using myself way back in autumn of 19 or early in 2020 I think what is factually demonstrable is that the outcome before us the Windsor framework provides a valuable and unique opportunity for Northern Ireland it wouldn't be available in the United Ireland that's again demonstrable fact and Northern Ireland really needs stability and certainty for businesses I think that should be a massively important criterion looking at all of this and having a USP is a really important thing that that's something we've never had and there's more hope and expectation of that through the Windsor framework than I can remember important also to recognize that any evaluation of this proposal can only be meaningful if there's a viable alternative and if we accept the trilemma and the UK has the two that the UK chose actively consistently were avoiding a hard land border and they've been even in recent months very clear and consistent that is one of their choices and the choice of leaving the single model across the union as at least for Great Britain then if you choose the those then something like this model is inevitable isn't there's that's that's where we go and the the only question is how to de-dramatize it make it as practically manageable as as low-key as possible and I think there's awkwardnesses around some of the seven tests that I've written and talked about the active union which I think should be reasonably clear that that's not actually compatible with the 1998 Belfast Good Friday Agreement and it came into the debate because of the way the court case went on the challenge but I find it disturbing that that was referred to in the protocol bill and is in the a lot of the rhetoric that's around is that I'll ask the question is that really something we're looking at in 21st century trade policy so more generally in all the discussions over nearly seven years something like the Windsor Framework protocol about approach I haven't seen any any better idea and I think that's part of the question those put back if not this then what what what actual alternative is it available so while it's I think unwise to oversell the Windsor Framework it is complicated it does involve major compromises for an immense amount of detail but stepping back it seems to me to present a very real and significant opportunity to draw a line under a very difficult debate move forward that it is a new way forward for the UK for the relationships between the UK and the and that's my general impression and hopefully hope that that things can and will settle so that's what I wanted to say nothing I'm happy to go into questions and discussion


Doing two workouts per day is pretty common amongst high level athletes of almost all endurance sports, including running, swimming, cross country skiing, and so on. But not for cycling.  If they plan on riding more that day, then they'll simply do one longer ride as opposed to riding twice. Why is this? Well for starters, our bodies are better able to handle long periods on the bike than they are, say, long periods of running, both from a recovery and injury standpoint. On top of this, bike races are generally longer in duration than your average event in other endurance sports. For example, your average pro road race can last four to six hours or more, which is two to three times longer than it takes an elite marathon runner to run a marathon in around two to two and a half hours. And a marathon is considered a long event in running. Again, a five hour road race is not considered long, that's just standard. What is this dude talking about? I've never seen an option for a five hour race on Zwift before. Given this, it makes sense that cyclists would naturally gravitate towards doing one long ride and then calling it a day. But is there something that cyclists are missing here? Is there some sort of physiological benefit to doing two workouts in a day? And if you're forced to ride twice in a day, maybe because you commute to work or because you spend so much time training indoors that splitting up the rides is beneficial for your motivation, then is doing this helping you or hurting you? This is what I'm going to be addressing today by taking a look at what the science has to say on this topic. Now it's important to note that the research here is pretty limited, but there are still some interesting findings that can give us some insight into the pros and cons of doing two workouts per day.  And the order in which you do them and the amount of recovery time you give yourself between these two workouts matters. All right, without further ado, let's jump into the science. This study put two a day training to the test by having subjects follow one of two training patterns. In the first, subjects alternated between a 100 minute steady state aerobic ride one day and an eight by five minute interval session the next. The other group did both sessions on the same day every other day so that the volume was the same and both groups trained like this for three weeks. I've got to say I'm not too impressed with how they structured the training in this study and that will continue to be a theme in the two a day research for whatever reason. First of all, if somebody's going to train twice per day, they're not going to only train every other day. A much better solution would have been to have both groups do the same volume, but one group only does one ride per day and the other group splits the volume into two rides per day. Also, the two a day group does the steady endurance ride before the interval session. Again, not the way I would have structured it because this will negatively affect the quality of that interval session. But it appears that they did this to see what the effect of doing these sessions with low muscle glycogen would be. And sure enough, glycogen levels were significantly lower in the two a day group, which as you might expect resulted in the subjects training at a lower relative intensity. Although by the last week of the training, this group seemed to be catching up a number of physiological responses happened in this two a day group, including an increase in resting muscle glycogen concentration and whole body fat oxidation while riding. But performance in a one hour time trial was similar between the two groups. While the performance was not different between these groups, the physiological changes highlight some potential benefits of doing two a day training. And these benefits have considerable overlap with doing fasted training in which someone trains in a fasted state, usually by skipping breakfast before they go ride. That being said, now would be a good time to point out that the research on fasted training is mixed. It appears that fasted training shows beneficial effects in terms of signaling and transcription. But to date, few studies have been able to show any effect on performance. And given how important carbohydrates are to performance, this isn't surprising. That being said, there are certain fasted training strategies that do show promising results. For example, train high sleep low in which athletes train with high glycogen late in the day and then don't completely refuel afterwards so that they can go to bed in a low glycogen state and train in a low glycogen state the next morning. If this method sounds like pure torture to you, then I'm right there with you. Well, yeah, if these people were denied access to hypergain, beast mode, mask gain, or raw addition before they ride that morning, then technically, that is considered torture in 23 different countries. I wouldn't generally prescribe this to somebody, but it does appear to improve performance in a number of studies. And judging by the adaptations made in the last study that I referenced, the effects seem to be similar with two a day training. This study on twice a day versus once a day training was set up very similar to the first with three weeks of training in which subjects did a hundred minutes of endurance training followed by a high intensity interval session, either two or 14 hours later, essentially making it a two a day or once a day pattern. The study looked at a wide range of fitness markers and the only two that showed any difference between the two conditions was mitochondrial efficiency and perceived effort, which both improved more when subjects did two workouts per day. I wouldn't call this strong evidence that two a day training is better, but it is something. And there are other studies like it that test this once a day versus twice every other day approach. And some of them do look promising. However, from this review looking at many studies on the topic, despite increasing the muscle adaptive response and reducing the reliance on carbohydrate utilization during exercise, there is no clear evidence that these strategies enhance exercise performance. Low glycogen training is a reoccurring theme that you see with two a day training. And while it appears that there are some physiological benefits, the evidence that this actually translates into an increase in performance is pretty weak. But is this low glycogen state even the reason for these adaptations in the first place? As the intro to this twice a day study puts it, it's unknown whether this greater signaling response is due to performing two exercise sessions in close proximity as a first exercise session is necessary to reduce the muscle glycogen stores. Basically, these studies have subjects do a glycogen depleting workout in order to train in a low glycogen state shortly thereafter. But this is a potential confounding factor. What if the simple act of doing two workouts in close proximity to one another is the reason for these adaptations? The study tested this by having subjects do the second session two hours or 15 hours later, so effectively a two a day or once per day approach much like the previous study. But the difference was that the second trial in both conditions would be in a low glycogen state. By doing this, they could rule out whether it was the low glycogen that was causing the adaptations or the close proximity of the workouts. What they found was greater physiological adaptation with the two per day approach. This led them to conclude that the greater signaling with the so-called train low approach can partially be attributed to doing two exercise sessions in close succession rather than exercising with a reduced muscle glycogen. So it appears that the benefits of two a day training may have something to do with the fact that you're doing two rides very quickly one after the other. Is this a point in favor of two a day training? I don't think so and here's why. If we take this quick workout succession idea to its logical conclusion, there is no quicker succession of two workouts than just combining the two and doing one longer ride. Then you effectively have zero time between the two workouts. Also, even if training with low glycogen is the main driver behind these physiological adaptations that we're seeing in these two a day studies, then we can still achieve this by doing one longer ride per day because the longer you ride, the lower your glycogen stores will be and either way we're training in a low glycogen state. Again, it would be great to see a study in which one group does one long ride per day and then the other group does two shorter rides per day. Make the total volume the same between the two groups and see which group gains the most fitness by the end of the study. Unfortunately, we don't have that right now and given the research that we do have, I would say that the evidence that riding twice per day has some sort of extra benefit is pretty weak. Of course, all of this assumes that you have the time to do one long ride regularly in your training. And for many people, this simply isn't an option. And for these people, riding twice per day can be a good solution. Let's not forget that training volume is important for making improvement. Optimal training requires combining lower intensity longer duration sessions with fewer higher intensity bouts. If you don't have time to do a long ride multiple times per week or you're stuck indoors and the thought of doing five hours on the trainer is quickly squashing your motivation, then oftentimes your best option is splitting that workout into two during training periods where volume is prioritized. If you can get to your weekly volume goal by doing two days, then this is better than having to compromise on your weekly volume and sticking to one ride per day. Ideally, though, you would still have one day per week where you go out for that one long ride. Also, if you are going to ride twice in a day and you have any sort of intensity plan that day, then I would do the intensity during the first ride. As we saw from the research I referenced, that first ride will reduce your muscle glycogen stores and this will reduce the quality of that second ride that day. I actually wouldn't be surprised to see more improvement from the two-day group if they had flipped the order of the workout so that they were performing the interval session first. Doing two rides in one day is not the only time that two-day workouts comes up in training, particularly when you throw weightlifting into the mix. If you're a serious cyclist, then you should be lifting if you want to improve your performance and at a certain point you will have to lift and ride in the same day. So what is the best approach here which should be done first and does the amount of time between these two sessions matter? This meta-analysis looking at the effect of concurrent strength training and endurance training sequence found that lower body strength was significantly higher when strength training was done before endurance training. This compromise in strength training may last six to eight hours after endurance training, but for maximal aerobic capacity the exercise sequence has no impact on the ensuing adaptations and this preferred order has been confirmed in many studies. What does this mean in terms of how you should time your gym sessions? Well it all depends on what part of your season you're in. In the off season and even early on in the base season when you're prioritizing your gym sessions, it makes the most sense to do the gym session first and preferably after a rest day so that you can be as fresh as possible for that gym workout. This changes as the season approaches though. Remember that our goal is to become faster cyclists not necessarily to gain as much muscular strength as possible and if that is your goal then perhaps this is the wrong channel for you. As your peak approach is you want your high-intensity sessions to take priority over every other workout that you have on your calendar including your gym workouts. If you have intervals and a gym session scheduled on the same day then do the intervals first. If it's just an endurance day then the order is less important but you probably will get a little bit more out of that gym session if you do it first. Although at this point in the year you'll probably just be doing maintenance lifting and being as fresh as possible for that gym session is less important. Finally it's a good idea to separate the two workouts by a couple hours so you feel better for that second workout. If I'm doing a gym session and a ride in the same day and the day is relatively free and I can schedule these workouts whenever I want then I'll usually do the first workout shortly after I wake up in the morning and the second workout later in the evening usually right before dinner. Huh well if there's one thing I got out of this video is that this dude has way too much time on his hands. All right back to scrolling through cycling meme pages on Instagram. Thanks for watching if you enjoyed this video be sure to give it a like subscribe for more science-based cycling content just like this and share this video through cycling friends. I'll see you in the next one.


Welcome to Caltrans LSIT LS exam preparation course. One aid in your preparation for California licensure examinations. A word of caution, don't use this course as your only preparation. Devise and follow a regular schedule of study which begins months before the test. Work many problems in each area, not just those in this course's workbook, but problems from other sources as well. This course is funded by Caltrans, but you and I owe a profound thanks to others, the courses instructors from the academic community, the private sector, other public agencies, and from Caltrans as well. We wish you well in your study toward becoming a member of California's professional land surveying community. Hello, my name is Luke Wilson. I'm a land surveyor with Caltrans Geometronics Branch in Sacramento. My associates Ed Zimmerman, CJ Vandergrift, and I will be presenting this unit of the Caltrans land surveyor examination preparation course on route surveying. I'll begin our presentation with an introduction to the topic and the route surveying process. And then Ed will discuss horizontal curves followed by CJ's discussion of vertical curves. After that, I'll be back to discuss a recent land surveyor exam problem. Route surveying includes all surveying necessary for designing and constructing engineering works. Here at Caltrans, we normally think of route surveying in relation to road construction projects. In fact, highway construction probably accounts for the bulk of route surveying work. Other examples of route surveying are surveys for railroads, pipelines, transmission lines, canals, and airport runways. Other civil engineering projects like subdivision design, grading plans, and site plans, though not route surveys per se, utilize the basic techniques of the route surveyor. The route surveying system includes four steps. Reconnaissance and planning, design, right of way acquisition, and construction. During the planning stage, alternate routes are identified from small scale mapping. Then preliminary studies are undertaken to determine potential engineering problems, environmental concerns, and to estimate costs of various alternatives. The planning process culminates with the selection of a preferred alternative. The design phase of the project is undertaken with large scale mapping, generally produced by photogrammetric methods. Traditionally, designers have used paper maps, and designs have been done on hard copies. But this method is being rapidly replaced by the use of three-dimensional digital train models and computer-aided design and drafting systems. The first step in the design phase of the project is to determine an alignment. This requires the survey of a preliminary alignment, either on the ground or using large scale mapping, or in the CAD system. The second step is to design a typical finished cross-section for the work. The typical section is compared to each actual ground cross-section, and earthwork quantities are computed. The alignment is then adjusted until an optimal design for safety, economy, and utility is obtained. The next phase of the project is the right-of-way phase. Surveys are undertaken to develop survey information needed to acquire property rights for the project. Right-of-way surveying problems are covered in our units on boundary surveying and legal description writing. The construction phase is the final phase of route surveying. In this phase, land surveyors are called upon to set points on the ground to control the work of building the project. In the course of computing the location of improvements and the setting of construction stakes, conditions are often found that require design revisions. This is a favored source of exam questions. Routes are described in relation to a control line. For a highway, the control line is typically the center line. Distances are measured along the center line from the beginning of the project in units called stations. Each full station is 100 feet. Distances are given along the center line in stations plus feet between stations. For instance, if the measurement along the control line is 1,050 feet from the beginning of the project, the station would be 10 plus 50, which is 1,050 divided by 100 plus the remainder. Distances measured perpendicularly or radially from the control line are called offsets. Offsets are generally designated as left or right of the center line. Left and right are determined by your view of the project if you are standing on the center line looking in the direction of travel or increasing stationing. Normally offsets to one side of the control line are given negative values, while offsets to those of the other side are given positive values. Together, stationing and offsets define a plain coordinate system for the project. Any point within the project can be easily located by station and offset. Elevations are added to the system to give it three dimensions. Elevations are either referred to a standard datum like the North American Vertical Datum of 1929 or to the control line. When referred to the control line, elevations are given as cuts and fills. Cuts and fills are differences in elevation between an identified point on the control line and any other point in the project. A cut from the control line to another point is a decrease in elevation, while a fill is an increase in elevation. During the route surveying process, elevations are generally used to begin with, while cuts and fills are the reference system used when the process moves from design into the construction stage. Most questions on the land surveyor exams focus on the design and construction portions of the route surveying process. So let's walk through the design and construction phases of a typical project. Reconnaissance and initial studies for our highway project have identified the saddle shown here on our large-scale aerial mapping as a portion of the route. The first step in the design process is to construct a preliminary horizontal alignment. This is done by laying out tangents as shown here. Changes in direction of the route are designated as PIs or points of intersection. Positioning of these preliminary tangents is determined by topography and the change in elevation between the various PIs. In our example, the PI at the top of the hill in the saddle is placed along with the other PIs along the route so that changes in elevation between them meet design criteria. Elevations for the PIs are measured in the field or are obtained from a map or digital train model and grades are calculated between PIs. Grades express the change in elevation along a line and are quantified as a percentage of slope. The relationship is change in elevation divided by length of the line. A change in elevation of one foot between two PIs that are 100 feet apart would yield a grade of 1%, one foot divided by 100 feet. If elevation increases with increasing stationing, grade is expressed as a positive value. If elevation decreases with increasing stationing, grade is expressed as a negative value. Next, horizontal curves are designed to provide a transition for each change in direction. Design considerations such as site distance and speed of travel determine the selection of radius length for the curve. Using the mathematics of circular curves which Ed is going to discuss, the length between the PI and the beginning and end of the curve that is the BC and EC of the curve and the distance along the curve can be determined. With this information, stationing can be calculated along the curve. Next, elevations on the ground are plotted along the alignment. This can be done by staking the alignment and running levels or by plotting the intersection of the alignment with contours from a map or a digital terrain model. What you get is a ground profile with elevation plotted in relation to station, like the one shown. Next, a vertical alignment is plotted to fit the ground profile. In the case shown here, the positive grade line coming up the hill into the saddle intersects the negative grade line going on down the slope out of the saddle. The point where these design grades intersect is called the point of vertical intersection or PVI. For design considerations, such as site distances, smooth parabolic transition curves called vertical curves are designed to connect the grades. The beginning station, BVC and ending station, EVC of the curve and elevations along the curve are calculated and plotted on the profile using the mathematical relationships that CJ will be explaining. Rarely is an alignment designed in a direct linear fashion. The method is more of a series of loops in which information obtained in one step is fed back into the process requiring changes to other steps. Adjusting PI locations, changing curve radii and changing grades and links of vertical curves all demand an intimate knowledge of route surveying calculations. The alignment when complete is a mathematical relationship based on tangents, curves, grades and vertical curves. When the alignment is complete and stationed, the second part of the design process begins. A typical cross section for the work is designed. The typical cross section represents a view of the finished work at right angles or radially to the control line. Shown here is the typical section for our highway project. Dimensions or offsets are given from the center line to hinge points or changes in grade on the section. Typical hinge points shown here, moving from right to left, are located at the top of cut, flow line of ditch, center line, shoulder and toe of fill. Elevations of the hinge points can be calculated by using the elevation of the center line from the vertical alignment and changes in elevation shown on or calculated from the typical section. The change in elevation from the center line to the left shoulder in our example could be shown as a grade from the center line. In this case, grade times offset distance will equal the change in elevation. Slopes like the side slope shown on the right side of the section are typically noted as ratios. For instance, a one to one ratio indicates that for each one foot increase in offset, there is a one foot change in elevation. Ratios and grades shown on the cross section can be used in conjunction with offset distances to calculate cuts and fills in relation to the control line. After the typical cross section is developed, ground cross sections are plotted from direct measurements in the field or are generated from paper maps or digital terrain models. At given stations, the ground cross section and the typical design cross section are plotted together like the one shown here. At this particular station, there's an area that represents material that will have to be removed during construction. Here labeled the cut area. Some of this material can be used to place the embankment necessary in the area shown as fill area. Volumes of earthwork can be computed using these cut and fill areas. On this sketch, the red lines represent the ground cross section while the yellow lines represent the typical design section. This case is an example of a through cut which is a section without embankment, only excavation. Quantities are calculated by first computing the areas of sections A sub one and A sub two. This can be done by using the coordinate method for computing the area of a polygon. Corners of the polygon are defined by hinge points, grade breaks in the ground cross section and catch points, which are at the intersections of the typical section and the ground cross section. The volume is calculated by multiplying the average end areas by the difference in stationing. The formula shown will yield an area in cubic yards. After volumes are calculated for the route, adjustments are made to the alignment and the volumes are computed again. This process is repeated until the design is optimized. When the design is complete, the construction phase of the project begins. Construction slope stakes are set at catch points at the intersection of the design section side slopes and the ground section. Position of the slope stakes can be approximated graphically from the sections or computed by solving an intersecting line problem. Because ground lines are usually measured to the nearest few tenths of a foot, normally adjustments to the calculated positions must be made in the field when the stakes are set. You should be thoroughly familiar with alignment, earthwork and slope staking problems. The LSIT exam typically has a question on each of these computations. The LS exam you take will probably have at least one problem that will require use of several of these computations. I'll return to discuss a typical LS exam problem, but first, Ed and CJ will review the problems posed by alignment design. Thank you for the introduction Luke and welcome viewers to this segment of the Caltrans route surveying video. I'm a licensed land surveyor and work in the survey section of the Geometronics branch at Caltrans headquarters in Sacramento. In the past I have worked both for a private surveying firm and for the city of Sacramento. I also teach surveying at Sacramento City College where highway curves are among my favorite subjects. And now to the business at hand, understanding and most importantly, simplifying and working with horizontal curves. I want to emphasize that I will only address simple constant radius curves. However, an understanding of the simple curve is basic geometry, calculation methods and stakeout procedure is necessary to understand the more complex forms of curves that you will eventually encounter in your surveying career. Horizontal or circular curves lie in a horizontal plane and are used to connect tangents. Tangents are used for control and alignment of straight sections of various public works such as streets and highways, railroads, pipelines and canals. It is important to remember that all points lying on a circular curve are a constant distance or radius from a central locating point known as the radius point. Consider any horizontal curve as a portion of a complete circle. The math computations required for solutions of circular curves is not difficult. Almost all curve problems and solutions can be done using basic principles of trig, algebra and or geometry. The trigonometry involved in those curve computations and solutions is based largely on the sides and angles of a right triangle. All the curve formulas and equations to follow are presented in a format handy for use than electronic handheld calculator. Handhelds should be capable of trigonometric functions including radian conversion. The simplest form of a circular curve and the one most often encountered in surveying is tangent two and connects two tangent sections of a route alignment. The basic components will be shown in the next few graphics. There is no universally accepted terminology for the parts of a curve in surveying practice. Every surveying company or public agency seems to have different curve terms and abbreviations. Therefore, I will be using terminology and notation that I am comfortable with having lived with them for the last 30 or 40 years. Let's first look at the intersection of back and forward tangents of a soon to be formed circular curve. Keeping in mind that in our example the direction of travel and or stationing is from left to right, the tangent to the left of the point of intersection or PI is called the back tangent. The tangent to the right is the forward tangent. Back and forward tangents intersect at the PI forming a deflection angle I. Deflection angle I between the tangents is generally measured in the field or computed. Usually the PI will have either an assigned or measured station designation as part of the preliminary survey. The next element of our curve to think about is the radius or dimension of sharpness of the curve. For any pair of tangents, an infinite number of curves may be designed. Field conditions generally dictate the choice of size or radius of the curve. For instance, a larger radius curve would be required for a high speed highway allowing traffic to comfortably negotiate the turn. Mountainous terrain considerations may limit curves to smaller radii with a corresponding decrease in speed. As shown on the screen, two lines are generated from the center of the curve or radius point and connect to the beginning of curve BC and to the end of curve EC. The radius or R is the distance from the center of the curve or radius point to any point on the arc of the curve. Since a curve is always symmetrical around the PI, distances from the PI to the BC and EC are equal and are called sub tangent distances or T for a particular curve. In this next graphic, we have added additional basic components of our curve. Note that the central angle or delta for the curve is an angle included between the two radial lines. The delta angle is always equal to angle I at the PI and radial lines from the BC and EC are always perpendicular to the tangents. Some highway agencies and railroads use a degree of curve definition rather than radius to define the sharpness of circular curves. Since degree of curve frequently appears in many land surveyor examinations, I will give you a brief look at this definition and its relationship to radius. The two definitions of degree of curve are arc definition and chord definition. First, let's look at the arc definition. Highway surveying practice defines degree of curve by arc definition as shown in this graphic. This is the definition most commonly used. As shown, this definition of degree of curve is the central angle of an arc of curve subtended by an arc 100 feet in length. It is identified as D or degree of curve by arc definition. Degree of curve expressed by arc definition can be converted to a radius distance by the formula shown on the graphic, 5729.58 divided by degree of curve. D is always expressed in degrees and decimals of degrees when used in this operation. The second definition of degree of curve is by chord definition as shown in the next graphic. The chord definition is most often used by railroads and is defined as the central angle of an arc of curve subtended by a curve with a chord 100 feet long. It is defined as D or degree of curve by chord definition. Degree of curve by chord definition is converted to radius distance by using the formula shown in the graphic now on screen. Radius equals 50 divided by the sign of one half the degree of curve. D is always expressed in degrees and decimals of degrees for this formula. Although the degree of curve and radius are mathematically related and both define sharpness of the curve, the radius definition of circular curves is more prevalent in modern survey practice and will be used in the example calculations for the rest of this presentation. At this point, let's drop back and review two basic facts of horizontal curves. As shown in this graphic, angle I always equals delta or central angle and radio lines from the BC and EC are always perpendicular to the tangents. Let's move on to the next sketch. Note that the line from the radius point to the PI bisects all related lines and angles. Now let's start some calculation procedures by determining the sub tangent distances for our curve. As shown on the screen, the formula for this particular computation is sub tangent distance equals tangent of one half delta times radius. In the sketch, note the right triangle formed by a line from the radius point to the PI or midpoint of curve, hypotenuse, a radial line to the BC adjacent side and the back's sub tangent opposite side. The next thing to do is determine the station of the BC, easily done. Simply subtract the sub tangent distance from the preliminary station of the PI. The length of arc or actual distance traveled around the curve from BC to EC is computed next. To find this distance, multiply delta expressed in radians by the radius distance. To determine the station of the EC, add the length of arc L to the station of the previously calculated BC. The use of radian measure rather than degrees, minutes and seconds, greatly simplifies calculations for arc lanes. Most hand held electronic calculators will perform this conversion. The next element of a circular curve is the length of the long cord or LC. The LC length of long cord is shown in this screen and is a straight line connecting the BC and the EC. Note the right triangle formed by the midline of the curve, the long cord and the radial line to the BC. As shown in the sketch now on screen, the formula for computing the LC is twice the radius times sine of half delta. The graphic now on screen is used to show the angle identified in the sketch as the total deflection angle and its angular relationship to both the angle at I and the delta angle. A survey instrument set up at the BC, zeroed on the PI and then turned to the EC, will read one half of the angular value for angle I. The total deflection angle will always equal half delta. Since sub tangent distances are identical, triangle BC, PI, EC, is considered an isosceles triangle. Note that in the preceding graphics in discussion, each curve, though complete within itself, is a portion or partial arc of a complete circle. Therefore, all elements of the particular curve or arc have a strict geometrical relationship to each other and are unique to a curve of certain radius and central angle. If any two of the curve's elements are known, the remaining elements can be calculated from the two known values. This graphic is used to show how a particular arc of curve can be divided into a sub arc length, L sub one. Sub arc one starts at the BC and runs along the curve to POC sub one. Therefore, sub arc one will have among its other elements, delta sub one, long chord sub one, and deflection angle sub one. These values are always unique to their particular arc. Before proceeding into curve layout computations and layout procedure, let's take a look at some other elements of a circular curve keeping in mind that all elements of a curve are mathematically related. This graphic shows the external distance. This curve element is the distance from the midpoint of the arc outwards to the curve's PI. The computation to determine this dimension is performed as shown on screen. Determine the quantity one over the cosine of half delta subtract one from it and then multiply the difference by the radius of curve. The next curve element is shown on this graphic and is called the midordinate distance. This is the distance from the midpoint of the long chord to the midpoint of the arc. This measurement is determined by multiplying the quantity one minus the cosine of half delta by the radius distance. Now on with the business of computing and laying out individual points on a curve. The deflection angle between the back tangent and a line or sub chord drawn from the BC to a point on the curve POC is the deflection angle for that particular POC or station. If a particular POC or station's deflection angle and sub chord distance are known, layout of the station from the BC is easily accomplished. After the design elements of a curve have been finalized, deflection angles for each station on the curve that are required to be laid out are computed. Let's take a look at the complete curve ready for stakeout and compute some deflection angles and sub chords to lay out the curve. The radius of this curve is 550 feet and the central angle is 28 degrees, 35 minutes, zero seconds. The total deflection angle for the complete curve is half delta or 14 degrees, 17 minutes and 30 seconds. Calculation of the total arc length is shown on this graphic. The computation is total arc equals 550 feet times 28 degrees, 35 minutes and zero seconds expressed in radians or 0.498873. This equals 274.38 feet. Considering the sub arc defined as L sub one, we determined it has an arc length of 40 feet. This is based on the stationing of the BC being 21 plus 80 and the station of POC sub one being 22 plus 20. Three calculations are shown on this sketch. Determination of delta sub one, determination of half delta and or deflection sub one for the same arc sub one and determination of the chord sub one for the same arc sub one. L sub one's central angle or delta is determined by dividing L sub one 40 feet by the radius 550 feet which equals 0.072727 radians or four degrees, 10 minutes and one second. Deflection angle sub one D sub one equals four degrees, 10 minutes, one second over two or two degrees and five minutes. Next LC sub one is determined by twice the radius times sine of half delta or 1100 feet times 0.036358 which equals 39.99 feet. Therefore, using a theatolite set up the BC and zero to the PI, deflection angle D sub one is set off to the right and the distance 39.99 feet is measured, laid out from the BC on the line produced from BC to POC sub one or long chord sub one correctly placing station 2200 in its position on the arc of the curve. This method of curve layout by deflection angles can be used to stake any portion of a curve on the ground. Now for the final portion of our curve discussion let's take a look at computing and laying out a curve by using coordinates and inversing between coordinates of required curve stations and a setup point remote from the curve. Combining the computing powers of today's electronic calculators and state of the art electronic total stations it can be more efficient to lay out a curve using coordinates and inverse methods. In this approach to curve layout a centrally located or convenient setup station is selected. This point is not necessarily located on the curve but is selected to allow all points of the curve to be staked out from the one setup. As seen in this graphic the setup station is not located on the curve but is tied to the BC and EC by bearing and distance or coordinates. With all elements of the curve located on the coordinate system calculations for the curve data and also the actual layout are reduced to routine inverse calculations. This provides staked out data for bearing and distance layout of all required curve points using a single setup location. In practice the setup point is selected and tied to the curves control system either in the field by actual measurement or by office calculation. As shown in this graphic the BC, RP, EC and setup stations all have coordinate values. To determine a coordinate for POC sub one first determine L sub one by station differences as in the deflection angle method just discussed and then calculate delta sub one by the same process used in the deflection method. For example, if the BC station is 12 plus 46 feet and the station at POC sub one is 12 plus 80 feet L sub one 12 plus 80 minus 12 plus 46 equals 34 feet. Assuming a radius of 550 feet delta sub one equals L sub one 34 feet divided by radius 550 feet equals 0.061818 radians which converts to three degrees, 32 minutes and 31 seconds. Applying delta sub one to the bearing RP BC the bearing RP POC sub one is determined. Using the coordinates of the RP the coordinate of POC sub one is computed. Inversing between the setup point and POC sub one determines the bearing in distance to be laid out to correctly position POC sub one on the arc. Coordinates are calculated for each POC that is to be set to define the curve by using the bearing radius from the radius point. The bearing of each sub POC is determined by applying its sub delta to the bearing of line RP BC The resulting coordinates of individual POC stations are used to obtain bearings and distances to the POCs from the setup point by the inverse generation process. All calculations should be done in a logical sequence and be neatly tabulated. There is an increase in computation time for the coordinate method when compared to the set point. to the deflection angle method. But this increase is more than made up for by the decrease in time required for field layout. Well, I've pretty well used up my allotted time discussing the basics of circular curves. I realized that only the bare necessities have been addressed in my presentation. Hopefully with study aids such as the workbook and reference books listed in the bibliography you will be able to cope with the mysteries of circular curve computation and layout. Thanks for your attention and I sincerely hope that I was able to make the horizontal curve process a little more user friendly. Good luck with your surveying career in general and with the land surveyors examination processes in particular. I now want to introduce CJ Van de Gryff, a land surveyor for Caltrans, who will discuss the aspects of vertical or parabolic curve computation. CJ, it's all yours. Thanks Ed and hello viewers. My name is CJ Van de Gryff. I'm a surveyor at the Hilltop Field Office in district four. I've been surveying for approximately 12 years and have been licensed since 1987. I will be presenting vertical curves as a portion of the route surveying unit. Simply put, vertical curves are parabolic curves that lie in the vertical plane. Vertical curves are used in design to transition from one grade line to another in order to maintain safe side distances for passing and stopping and to provide comfortable riding conditions. The geometry of parabolic curves allows easy computation of elevations at any point on the vertical curve. Field applications of vertical alignments usually requires that elevations be calculated for specific stations or at regular intervals. These values may be derived by either the tangent offset method or the parabolic curve equation. Both methods are based on the following properties. The offsets from a tangent to a parabola are proportional to the squares of the distances from the point of tangency. This presentation will only discuss the parabolic curve equation. It is less complex and well suited to computer and calculator use. Other curve computation methods are no less correct and some familiarity with them is encouraged. Most of the sources listed in the workbook cover both methods. This graphic shows the two classifications of vertical curves. Curve A points upwards from its point of beginning or BVC and is called a sag curve. Curve B moves downwards from its point of beginning or BVC and is called a summit or crest curve. The elements of a symmetrical or equal tangent curve are as follows. BVC is the beginning of vertical curve sometimes shown as PVC or point of vertical curvature. EVC is the end of vertical curve sometimes shown as PVT or point of vertical tangency. PVI is the point of vertical intersection of the incoming and outgoing tangents. Capital L is the length of the curve in stations measured on the horizontal plane. One full station equals 100 feet. The distance from the BVC to the PVI is always one half the length of the curve. Small L is not shown here but it is often used to define the distance from the BVC to a station of interest on the curve. G sub one and G sub two are the grade rates in percentages with the tension to algebraic sign. G one refers to the tangent grade entering the curve and G two refers to the tangent grade leaving the curve. Little R is the rate of change for a vertical curve and is found by subtracting G one from G two, preserving algebraic signs and dividing by L, the length in full stations. For example, a vertical curve where the incoming G one equals plus 2.75% and the outgoing G two equals minus 4.25% with a length of 800 feet. Little R would equal minus 0.875% per full station. The rate of change is always negative for a crest curve and positive for a sag curve. The value of little R is the rate of change of the slope in percent per station. Since the rate of change for a symmetrical vertical curve is a constant, the following equation can be derived. The equation states the elevation of any given station is equal to one half the rate of change times the distance to the given station from the BBC squared plus G one times the distance to the station plus the elevation at the BBC. This next graphic shows where the elements of the equation come from. Begin with the elevation at the BBC. Then add algebraically the beginning grade multiplied by the stations along the curve. Then add algebraically the offset from the tangent to the curve. For example, let's say the equation, the station at the BBC of our curve is 10 plus 00 and the elevation is 100 feet. The elevation at station 12 plus 50 would equal minus 0.875% divided by two multiplied by 2.5 squared plus 4.25 times 2.5 plus 100 feet which equals 107.89. In practice, it's not always critical to know all the equations. We often just plug numbers into computers and record answers. But this one relatively simple equation will allow you to compute grades at any station on a vertical curve. Questions involving vertical curve computations are very common on both the LSIT and the LS exam. Since the computations are quite simple, the critical elements to solve the vertical curve are often hidden in with lots of unneeded data. Always identify which of the basic components are given and which are required to find. We've just looked at finding an elevation on a vertical curve given the curve length, the tangent grades, and the stationing. A problem on the 1991 exam was presented as such. A 12-inch water pipe was found at station 18 plus 50. The top of the pipe elevation at centerline was given as 730.92 feet. Required was to design a vertical curve to clear the water pipe. Carefully using all the information given, the length of the curve became the only unknown. It is helpful when setting up an equation to list what is known and therefore identify what must be solved for. In our example question, the elements given are as follows. G1 equals plus 8.75%. G2 equals minus 1.50%. The BVC station is 16 plus 50 and the BVC elevation equals 720.23. The elevation needed to clear the water pipe at station 18 plus 50 is 734.32. And little L equals 2.0 stations from the BVC to the water pipe, left to find the length of the curve. If we plug these values into the basic parabolic equation, it looks like this. Some basic algebra shows the value of L, in this case rounded, to be 6.0 stations or 600 feet. The final aspect I want to cover is locating the station and elevation of the highest and lowest point of the vertical curve. This can be very helpful when checking profiles for conflicts like our water pipe. At the higher low point, the slope of the tangent to the curve equals zero. Therefore, the value of little L, the stations from the BVC to the higher low point is equal to G1 divided by the rate of change. Changing the sign of this value will always yield a positive number. This provides a good check that all the algebraic signs have been carried correctly. Using the values for our water pipe problem, the rate of change equals minus 1.708. Little L then equals 5.120 stations from the BVC. Therefore, the high point station is 21 plus 62.20. The elevation can then be calculated using the parabolic equation. The elevation of the high point in this case does equal 742.64 feet. This concludes my portion, and I want to wish you all success in your pursuits as professional land surveyors. Now back to you, Luke. Thanks, CJ. Now we're going to discuss problem B5 from the 1990 land surveyors exam. The problem is in your workbook. We're provided with information in the form of a street centerline profile, a street section, and the site plan you see, which I've modified for our use. We're required to answer five questions about the site plan. If you want, you can stop the tape now and solve the problem on your own. Then turn the tape back on and compare your method against mine. This site plan problem can be solved using a route surveying methodology because it is based on a control line, in this case, the centerline of the street. The first step in the solution is to read and study the whole problem. The problem statement, you have been provided design criteria as shown on the diagrams below and on the facing page. Problem requirement, answer the following questions using the information provided in the diagrams. One, determine the ground elevations of the back of sidewalk at the following locations. Driveway centerline, southeasterly property corner, southwesternly property corner. Two, provide the grade percentage between point C and the building pad. Three, what is the slope ratio from point A to the toe of slope? Four, calculate the cut from the back of the sidewalk to the sewer lateral invert at the property line. And five, calculate the distance from the north property line to the toe of slope at point B. Notice that questions one and four require back of walk elevations and that the other three questions require use of these back of walk elevations to develop their answers. To solve questions one and four, calculate elevations on the centerline of the street for stations that correspond to the southwest property corner, driveway centerline, southeast property corner, and sewer lateral. To do this, first, stations on the property corners must be calculated. Property corner stations can be calculated using the station on the driveway centerline, the dimension given from the driveway centerline to the west property line, and the width of the lot. The elevations can all be calculated using the street profile that is given. Two of these elevations are in a vertical curve section, so you must be familiar with vertical curves to solve the problem. From the street section, we find that there is a 0.33 foot fill from the centerline to the back of the walk. Adding 0.33 feet to the centerline elevations for each station will give us the answer to question one. Question four asks for the difference in elevation from the back of the walk to the invert of the sewer. Because we planned ahead and already know the back of walk elevation at station 12 plus 67, we need to only know the invert of the pipe at the back of the walk. We're given the invert of the pipe two feet from the house and the grade on the pipe, so we only need the distance from the position of the given invert elevation to the back of the walk to figure the difference in elevation we need. The site plan shows the swale as being five feet from the house and 25 feet from the back of the walk. With this information, we can determine the distance from our given invert to the back of the walk, which is 28 feet. Next, calculate the invert of the pipe and then the cut to the invert of the pipe. Questions two, three, and five all require elevations along the swale. We'll do question two first, because to do it, we will have to figure elevations at each grade break in the swale needed to solve both questions three and five. We begin with the elevation we obtained in question one at the back of the walk and the center line of the driveway. Dimension and grade from this point to the swale grade break in the driveway is given. So we can calculate an elevation at the swale grade break at the center of the drive. The elevation of the flow line at point D can be computed from the grades and dimensions given on the plan. Finding the distance from the swale grade break in the driveway to point F at the flow line of the swale is a bit tricky. Here's where you can use your years of experience pouring over architects' plans that always seem to admit key dimensions. The dimension from the west property line to the center of the swale at the center of the drive can be calculated and is 35 feet. The swale on the east side of the lot is five feet from the property line. Therefore, we can add these two distances, five feet and 35 feet, and subtract the sum from the width of the lot to obtain the distance necessary to calculate the elevation at grade break F in the swale. From point F, distance and grade shown on the plan give us the elevation at point E. Now for point C. With elevations at D and E and grades given from these two points to the grade break in the swale at C, we can solve for the elevation at C in the following way. We can write equations for the elevation of C from both point D and point E. The equation from point D is the elevation of C equals the elevation of D plus 0.015 times the distance D, C. The equation from point E is the elevation of C equals the elevation of E plus 0.02 times the distance C, E. We know that distance D, C plus distance C, E equals 120 feet. So distance D, C equals 120 feet minus distance C, E. Now we can rewrite our equation for C from point D by substituting 120 feet minus distance C, E for distance D, C. Giving us elevation of C equals the elevation of D plus 0.015 times 120 feet minus the distance C, E. Now we can combine the two equations as shown and solve for distance C, E. With distance C, E and the grade of 2%, we can easily calculate the elevation at grade break C and from that, the grade to the building pad. After question two, question three is a breeze. It asks for the slope from point A to the toe. We know the elevation of point F at the flow line of the swale from our work on question two and the fact that the top of the slope and point A are one foot above the flow line from the plan. We've already computed the back-of-walk elevation at the southeast property corner for question one so we know the change in elevation. From the site plan, we know that the dimension from the back-of-walk to flow line is 25 feet and that the top of the slope is five feet from the flow line and the toe of the slope is one foot from the back of the walk. This leaves 19 feet for slope. The grade is the difference in elevation between point A and the elevation of the southeast property corner divided by the distance allowed for slope on the site plan. The last question, number five, asks for the distance from the north property line to the toe of slope at point B. The elevation of the toe of slope is given on the site plan. The top of the slope is one foot above the flow line of the swale at point E, which we calculated for question number two. The change in elevation is easily obtained as a difference between the elevation of top and toe. The ratio of the slope is given as two to one so the distance from the top to the toe is two times the change in elevation. From the site plan, the distance from the top of slope to the property line is 20 feet. So the dimension from the property line to the toe is 20 minus two times the change in elevation between the top and the toe. As you can see, a lot of time and effort can be saved by proper planning and organization. The method you use is very important. Efficient method can be the difference between success and failure in your day-to-day practice as a land surveyor. On the exam, correct method becomes all important because of time restraints. Inefficiency on the job might cause evening or weekend shifts, but on the test situation, it can cause failure. With that in mind, I wish you good planning.


Hi everyone. As you are now aware, CFA is moving to the use of the radios or Sine Biocon for all radio communications with their stuff on operational radio networks and dispatch channels. The change to the use of Biocon was initiated by CFA after discussions commenced about the new model of CFA and IFRV interaction on radio networks across the state. In order to understand how this worked in other jurisdictions, CFA reached out to colleagues in the state fire services in the Ufis and Queensland, Fire Rescue and RFS in New South Wales and the Tasmanian Fire Service. All of these fire services used Biocon as their course line. Now that both CFA and IFRV are using the same radio channels on the RMR network in regional areas and that CFA will be responding more frequently to the IFRV and expanded mutual aid areas in the inner metro districts on the RMR network. It was agreed by all agencies, CFA, IFRV and ESTA, that a new single call sign be used statewide as this is the safest, most effective, efficient way of operating and of all its unnecessary confusion. From the 1st of September this year, CFA Acting Chief Officer Gary Cook has made the decision that CFA will transition to be used in fire comms. IFRV have been using fire comms since they came into operation on the 1st of July this year and ESTA have also adopted fire comms from that point in time. The Chief's decision will now say all agencies align and use a common call sign statewide. We understand that this is a significant change and will take some time to be used. For this reason, CFA has been working closely with ESTA and their fire operators to assist with the transition. If you forget to use fire comm after the 1st of September, you may receive a prompt from an ESTA operator over the radio such as an a la pump up fire comms. As per agreement between CFA and ESTA, please use fire comm in all radio comms from now on. Thank you. We will also be re-issuing updated dashboard systems for vehicles that provide guidance on structured radio communications and reference fire comm to assist with this change. Thanks for your time and stay safe.


Get your sprites moving with blocks from the Motion Palette. Try dragging a Move 10 Steps block. Click on the block to see your character move across the screen. Use a Repeat block to make your code repeat again and again. Slow it down by adding a Weight block.  Next, make it interactive by snapping a When This Sprite Clicked block on top. Now, whenever you click on the sprite, it dances back and forth. Explore other blocks in the Motion category and see how else you can get your character to move.