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Module 1: Design Guidelines for Pedestrian and Cycling Facilities

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Design of Pedestrian Crossing

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Now, let us look at, in this lecture, we'll look at, uh, how to design crosswalks or mid-block crosswalks, uh, along her, uh, urban. This is again as IRC one zero three, published in 2012. So what are crosswalks, uh, you know, crosswalks are, uh, the zebra crossing markings or the pavement markings that are. Uh, present either at signalized intersections or at other strategic locations, uh, which may be mid-block as well. Uh, these are provided so that pedestrians can cross, uh, can cross is the shortest possible route, right? Otherwise, uh, if the pedestrian have to walk for a long distance, uh, and then, uh, cross the road, they may not be taking. Uh, the pedestrian route and mainstay be using a motorized mode of transport. So in order to provide them the shortest, uh, crossing off, uh, a roadway or an urban street, these crosswalks are designed. So preferred crosswalks are always at grid. For example, this isn't at grid. Uh, crosswalk, it may be on a tabletop. So tabletop cross me a crosswalk, meaning, uh, it is a, there is a ramp that raises the crosswalk slightly above the, um, uh, right away or slightly above the, um, and then the markings are provided here, but these are also considered at grid. Whereas there are some crosswalks or they are called foot over bridges that are grid separated or. Above the grid. Okay. They're called foot over. So such kind of facilities are also crossings, uh, which are provided at certain locations where it is necessary dated, but they are not at grade their grade separated or they're above the ground or foot over. In another case, they may also be grid separated, but then maybe below the ground below grade, or they may be called underpasses. So there are three different types of. Crossings when you, uh, have to consider, uh, uh, crossing of pedestrians at urban streets or along urban streets, you can either design them at grid. You can provide them, uh, at, uh, uh, above grid or under grid, depending upon the situation. Crossings are a must at T junction. So whenever you encounter a, um, uh, a road geometry forming a T, so whenever you encounter, uh, something like this, yeah. You are encountered by her. Uh, you are encountered by a T junction at such a junction across work. Is there. Must right. You have to provide crosswalks. Otherwise people will not, our pedestrians will not be able to cross the road. So that is the basic principle of designing of crosswalk. They may be at grid. They're always preferred at grid. They may be on a table top, or may not be on a tabletop in the other locker. In the other situations, there may be some types of row provided above grid or beloved. Now crosswalks are often installed ad signalized intersections and select locations, right? These kinds of, uh, uh, markings, we zebra beat ladder zebra, eat ladder. We dashed it continental like this standard solid any kind of, uh, markings on the pavement denotes. Uh, crosswalk, right? There are some standard markings that denotes crosswalk. They are often signalized locations or at other select locations, select locations, meaning they may not be at an intersection. They may be mid-block, but there is a reason for providing a crosswalk. Without any reason, you should not provide crosswalks at multiple locations that will only obstruct the flow of vehicles on that street. So at either the junctions. Audit signalized intersections or at strategic locations, these crosswalks should be provided. Uh, the parallel lines. It would be 0.2, 2.6 meter in width and a minimum like 1.8 meter standard is three meter. So you have to at least provide a wit these two lines should be at least point to 2.6 meter apart. And the minimum length should be at least 1.8 meters. Standard length is usually three meters, so that the length of the crosswalk is nothing but the length, the width of the road that the pedestrian has to cross, right. Markings may be different. We've already seen the different types of markings. So in the last lecture, it was, we were talking about these kind of cross, uh, crosswalks. So these are provided at signalized intersections when there is an all red phase at all the four. Junctions. They allow people to crisscross, uh, at intersections, which they otherwise had to cross in a L shape. But now the other thing to, uh, think about when you're designing crosswalks is to look at the corner radius of the, um, streets. So these corner radius at the streets. Should be as small as possible, right? The smaller, uh, turning radius increases pedestrian safety by reducing regular speed. If this radius is too much, the vehicles will travel fast. If the vehicles turn fast, then there do not be enough time for the pedestrians to cross. Hence, one of the. Uh, safest designs at intersections that are always recommended is to have very small turning radio at the intersection. So that is one thing you should always remember. The other thing to remember is the ramp slope. The slope of the ramp should be between one is two, five, two, one is two eight. So when you are designing this crosswalk on a tabletop, right? So even you're designing the crosswalk on the table top. The ramp that you provide for the vehicles. This lab allows the vehicles to slow down because suddenly they see a change in, uh, inclination. They will slow down and that ramp should be anywhere between one is two, five to one is two it to ensure that the vehicles slow down at the crossing. Then the alignment with the desired lines, uh, pedestrian crossings at intersection should be located, says that there is minimum deviation from the path. Of travel, define better pedestrian zone. Often you will see that the design is such, but user experience tells us that people will. If they have to go from here to, from here to here, they will not take this part. They will usually take this part. So you will often see. Uh, part that is developed by the users themselves. So we have to keep this in mind when we design the, uh, design, the crossings at the intersection. So if there is the sh if there is a shortest part yeah. across in canvas design, we need to design it accordingly. Okay. So if the crossings have to be the shortest path between two points, So, uh, what we learned in this, uh, slide, uh, quickly summarizing them. You have to have a corner radius that is small. The coverages should not exceed six meter in residential areas. So that is kind of a guideline given VARC ramp slopes should be such that this load on the vehicles anywhere between one is to fight. One is two eight, and the desired line should be taken care off. the other thing to remember is at minor intersections, if the, uh, how to design for a crosswalk, right? If the intersection is not signalized, it is acceptable to raise the crossings that are perpendicular to the minor arms while the crossing at the major arms is provided at grade. So what happens is if it's an uncivilized intersection, Right. There is no uncivilized intersection between a minor and a major app. Right? So what is desirable here is raise the crossing data perpendicular to the minor arm. So when you're trying to develop a pedestrian crossing that is perpendicular to the minor arm, you can raise this on a tabletop, whereas. Along the major are perpendicular to the major app. You can provide it at grid. Okay. So that is one of the things to remember when you are designing between major and minor up for signalized intersections. If the crossing is at the level of the Gardner must be ramped. So each of the corners must be them, right? So if, if this is the sidewalk and this is the crosswalk, this is the crosswalk. Then there should be a ramp up, must be ramp. The width of the ramp should be at least a 1.2 meters. And the slope, no steeper. Then one is two. So these are some design guidelines. That ensure that there is a safe crossing, not only safe crossing for the pedestrian, but also keeping in mind the vehicles so that they will stop or reduce in speed while at the intersection, which may or may not be signalized. So you're always remember the distinction between a signalized and in on signalized intersection and how to provide a crossing at each one of them. Now, if it is a mid-block crossing, the next scenario could be that there is a, there are two, uh, intersections wide apart and in the middle of the two intersections people, there are a lot of activities that happen that are land users, uh, along that street, uh, that, uh, ensure that there is a lot of pedestrian activity. Then you are bound to provider mid-block crosswalk. So if, uh, this is the situation, uh, if this is the situation where, uh, there are two intersections that are so far from far away from each other, right? So these are the two intersections that are so far away from each other. And there is a lot of land use here that generates a lot of pedestrian traffic. So, instead of not only providing crosswalks at the signalized intersections, you also end up providing crosswalks somewhere mid-block as well. So this is, this is called a mid-block crosswalk, right? Is a similar situation is shown in both of these pictures. What, how do you do, uh, extra care has to be taken? While designing this mid-block crosswalks because it is in the middle of the block that the vehicles usually have arc top speed. Right? Uh, so when the vehicle has just crossed this, uh, signalized intersection and is now heading, heading South, it has already picked up pace because it has crossed the intersection and only here will it eventually reduce space because it is then approaching another intersection. So in between, right here where the crosswalk is, It may be at a very high speed. So when you are dealing with such a situation where there is high speed vehicles and no signals available at such a spot, when you design for a crosswalk, you have to be very, very careful and safety has to be paramount. So what you usually do is you provide curb extensions. For better visibility to on road motorists. So what you usually do is if the curve is like this on both the sites and you want to provide a crosswalk right here, you usually extend the curb out a little bit. So these are called curb extensions. You extend the curb inside, you extend the curb inside so that what now happens is. This vehicle that is coming here suddenly sees that there is something moving towards the, it, it sees the curb line moved towards this vehicle and the vehicle kind of stops. So somebody coming here they'll see that the curve is colorblind is moving towards this vehicle and they will stop. And on top of it, you can have a ramp up. On both sides up and ramp down on both sides and have the crosswalk design. So not only does it enable this vehicle to see better to see the, uh, but I still tried to cross better. It also shortens the distance that the pedestrian has to travel right now. He or she has to travel that distance. Whereas if there was no curb extension, they had to travel. Huh? Little bit of a greater distance. So what happens by curb extensions? It allows a, the motorists to visualize or to see the pedestrian more clearly the pedestrian who is trying to cross and B it also decreases the distance that the pedestrian now has to cross along the crosswalk. Right? So that is one way of providing mid-block crosswalks is to provide curb extensions. Okay. The other way is to provide a medium refuge Island, allow pedestrians, look for gaps in only one direction at a time. So the other way to do this is you can have a refuge Island in between and you can stagger the crosswalks, right? So the crosswalk is now kind of staggered. So the crosswalk is staggered. The person, this, this is a ramp you're provided the ramp. You provide no curb extension, but you're provided a ramp. And now, because there is a refuge Island here, this is either a refuge Island or a medium or whatever you may call it because there is a space for the pedestrian to stand at that position. Now he, or she can only look at this traffic. And not worry about this traffic while he, or she's crossing these lanes, then they stop at this refugee Island or the medium. Then again has to only worry about this traffic and not worry about this traffic and then crossover. Yeah. So these are two different design methods by which you can design a mid-block crosswalk. Again, you have to be very careful when you're designing mid-block crosswalk because. Usually the speeds of the vehicles between the two intersections is highest at some point in the middle of the two intersections and B, because, uh, there may or may not be, uh, too many people that are wanting to cross at that location. So, uh, the expectation of, uh, uh, motorists may not be, uh, very high to encounter a pedestrian. So because of these two reasons, you will have to. Very carefully designed for that mid-block crosswalk, uh, as per IRC, uh, crossings, not at, but in between the street connectivity, connecting to intersections. Uh, what it says is the spacing should be every 80 to two 50 meter, uh, in residential land uses. Whereas in commercial and mixed land uses, uh, anywhere with an 80 to one 50 meter. And in high intensity commercial areas, it should be pedestrianization as much as possible, right? When there is a lot of pedestrian activity in highly commercialized zone, you should provide crossings as per the need. They're crossing stakes, the priority and vehicular movement does not take priority. Okay. We have already talked about mid blocks. Mid-block with curb extensions provides better visibility with refugee islands. It allows pedestrians. So we have already looked at each of this. These are some standards that I R C recommends. Uh, now a typical, uh, curb ramp design is also a, um, uh, depict, uh, is also shown in, uh, IRC, which has to be taken care of when you are designing for a, uh, for, um, uh, A curb and a crossing. So again, remember universal design has to be applied, right? It has to take care of, uh, uh, pedestrians, which who are especially able. So not only are we, we're talking about, uh, small children and, uh, uh, elderly people crossing, but also about specially able people crossing by themselves, they may not be always accompanied by somebody else. So you are designed. Off your sidewalk or you're crossing, or your crosswalk should always include a universal design principles. So you have to have it flared, uh, flared ramp, a maximum of one is to 10 grade, right? A flared flared, meaning it has to have a flare like that. Uh, it has to have a grade of my, uh, maximum gradient of one is two 10. That has to be tested. Tile flooring are tactile paving. That'll allow the, uh, the, uh, person who, uh, who is visually impaired, uh, to walk, uh, it guides them to walk, uh, properly. Uh, then there has to be a guiding strip, which is 300 millimeter, 300 mm, wide, uh, that has to be provided. And then there has to be a continuous long. It, you know, Um, tell paving and, uh, uh, and guiding blocks so that it enables, uh, the differently abled people to navigate through the sidewalk as well. So these are some design principles to be kept in mind when you're looking at, especially the crossings. So these are the where people will get on and off the sidewalk. Uh, when it comes to, uh, pedestrian signals, we have already, uh, looked at how to design for pedestrian signals. Uh, Preston signals are designed basically considering the minimum time gap required for the crossing, right? Minimum time gap required for the crossing. And it is given by this formula where the first part of the formula takes care of the time to cross. Right. The time to cross, uh, the, uh, uh, the second one takes into account the time taken by Rose to follow one after the other, because, uh, because the width of the crosswalk, there will be multiple people may be crossing in multiple rows and they may be queued up one behind the other. So there is some time that is lost if there is queuing. And also if there are multiple rows, there is friction. So there is some time, additional time that. Uh, it takes to cross the sidewalk across the cross cross the carriage way. And the last one is the time taken to begin. Right? You see, you have to start from inertia. So the people who are closest, uh, to the, uh, uh, to the pavement start first, there's the people who are queued behind they start later. So there is some startup time that is involved. So this will give you the minimum green time. For the pedestrian crossings at the pedestrian signals. If you have to design a pedestrian signal, you have to at least give that much green time, or which is called the minimum time gap in seconds in order to allow for the pedestrians to cross. So if you just look at a simple, uh, uh, exercise where you are, you have been asked to calculate the time gap for a platoon of 27 school children. Who are crossing five in a row, right? Five children per row, consecutive time of two seconds. Uh, they have a consecutive time of two seconds between each other. Uh, with the, the crossing section is 7.5 meters. And the walking speed of the children is 0.9 meter per second, with a start-up time of three seconds. So how much minimum time gaps should they give you already know the formula, uh, for that, uh, N. Uh, if you just have to find out N you have 27 children and five per row. So if we divided by that, you are approximately, there are six roles that are formed, right? So if there are six roles that are formed, you already know the, uh, the width of the pavement. You already know the speed at which average speed at which the children, uh, uh, uh, cross, uh, the children are walking. You already know that, uh, seconds is that consecutive time. So. Time between two children. Walking is two seconds. Uh, your calculator and a six, six minus one. And the startup time is three seconds. So you are getting her time gap. The platoon is 21.33 seconds. That is needed for the entire platoon to cross that, um, category. Now, when you have to design a refuge Island, we have already discussed. About what a refugee Island does. It allows for the pedestrians to cross two different streams of traffic by not by only looking at one stream at a time, right? If there are more than two lanes per direction than a refugee Island is usually recommended that if there are two lanes in one direction and two lanes is another direction, it is not advisable to provide just one long crosswalk. Uh, especially if the lanes are wide enough. So you have to provide, uh, Mid-block a refugee Island. Then the grub pedestrian crosses once traffic stream waits in that refuge added for a gap to cross the next traffic street. Uh, so the dimensions refugee Island dimensions, uh, should be the same. The refuge should be the same width as the pedestrian crossing. And the depth should be no less than two meters, right? The width should be the same as that. Uh, the width should be the same as them. Uh, the, which will be the same as the pedestrian crossing, right? So if this is the refugee Island, which should be the same as the same as the, um, pedestrian crossing, the depth should be no less than two meter enough to park a wheelchair. So that is kind of, uh, uh, design criteria that has been given here. So this should be as much as the crossing and depth should be. At least. Two meters, right? Which should be as much as the pedestrian crossing width. So this is the pedestrian crossing width and the depth should be at least two meters so that a wheelchair can be easily part on the refuge Island. The refugee area, median is greater than crosswalk width, or 3.6 meters, a surface area of at least 4.6 square kilometer. If there is a refuge Island. So if there is a refuge Island that enables you to enables you to, so this is a refuge Island. So if there is a refuge Island that enables you to cross at multiple directions, so that refuge Island should have at least, eh, area of 4.6 square meters. Right? So this isn't a very big intersection and there are multiple refuge islands, right? So these are foods islands. You can. Go, you can cross this weight here, right. Even then either cross this way or that way. So it allows you multidirectional crossing. So if you have a refuge Island of salt that is usually provided when there is a, um, left channelization available, uh, for vehicles to turn left, uh, if they're channelized, then there is a refuge Island that is provided here where you can cross either this way or that way. And such a refuge Island should at least have a area of 4.6 square meters. this again is a design offer. The Fiji islands on a one on a wide two-way road. Median can be used for, uh, pedestrians for weight waiting. As we had already discussed the refuge Island. Can also be a medium, right? It can also be a medium between the two, uh, uh, between the two directions of traffic where people can stop media and it can be landscaped with three plantations, regular street temperature, and treating with a filtering and stormwater. So that is how, uh, you can treat, uh, a median. So. Uh, we often, we often think that the median, uh, should not be taken care of if there is grass growing on the median. Uh, that is the last thing that we should be thinking about. Usually that is not true. Cause medians are for not only for beautification and landscaping, they have other functions as well. So the medians have to be properly taken care of because one of the functions is that it may act as a refuge Island for pedestrians. This is another example, offer a crossing design for specially abled person. Oh, here are multiple refuge islands. You could, you can look at that. So this is a refugee Island. Uh, this may be a service lane to the cross, the service lane, and then the main right-of-way cross it again. You have a refuge Island, then you can, again, cross there. Service lane. So the refuge area should be at least 1.2 meter wide and depend upon the traffic speed. VIT varies with speed of vehicles on road 1.5 meter width for speeds, up to 42 48 kilometer wide, uh, 42 48 kilometer per hour and 2.4 meters for anything between 56 days. So. What internet is telling you is that you have to design these refuge islands, uh, based on the speed of the vehicles that are in the traffic stream. Right? If the speed is too high, what happens is if the speed is too high, then the number of people that have accumulated in the refuge Island will not be able to, uh, cross the Lake across the road very quickly. Right. So there'll be more and more people that start on. That keeps on accumulating here. And then, then, uh, it becomes very crowded. So based on the speed of the vehicles on, on the road, the area of this refugee Island has to be decided upon the lower the speeds. The lower can be the area of the, if you Janet, again, if you take a look at the another problem, A road that is 30 meter wide needs a pedestrian crossing with them. Refuge Island. It is regularly crossed by a platoon of 30 school children, six in a row. These children cross with the consecutive time of three seconds, a start-up time of 3.5 seconds. The walking speed of 1.1 meter per second, to increase the comfort of the pedestrians while crossing the city. Officials decide not to set up. Better in green time of the pedestrian signal beyond 30 seconds. Right? Not more than 30 seconds determine and justify the position of the refuge Island on the cross section of the road. So if you have told to do such a, an intervention, such a design, what should you do? You should first calculate what is the green time are? What is the minimum gap that should be provided for this kind of a situation? You should calculate N you already know, uh, there are 30, uh, students that cross six in a row. So, and you have been told that a maximum of 30 seconds of screen time is given. So if a maximum 30 seconds is given and a, you know, the speed, average speed, you know, the consecutive time, you know, and it's a five and in those startup time, So you can know the VIT author crosswalk. You can know that with, so therefore a median refuge Island at the midway of the road solution is required for a safe and comfortable crossing. 30 seconds is not enough for safe crossing off 15 meters. So fifth. So here, what you are saying is that our road is 30 meter wide. So the road is 30 meter wide. And the green band that you have provided is only 30 seconds. So in that 30 seconds, what you are seeing is that people can only cross 15.95 meters. So the rest 14 odd meters, they still have to cross. So that tells you that there is a requirement for the refuge Island somewhere in the middle of the road. Right? So that is what. Justifies that there must be a median refuge Island, somewhere. The midway of the roadside uh, IRC one Oh three also, um, uh, recommends, or it does not recommend, but it provides, uh, some guidelines for, uh, mid-block crossings as to what are the, what different types of signage can be used. It also recommends that in pavement raised markers could be used along the crosswalk that will reflect a light onto the, uh, onto the motorist. And the motorist will be able to see, uh, the pedestrians crossing. You could have overhead pedestrian signs that alert, uh, the motorists that there is somebody who is crossing on the crosswalk. You can always have a pedestrian signals that have some animation in them. Uh, about, uh, pedestrians crossing, uh, at schools zones, typically you should provide signs that says, uh, schools or with the schools on simple symbol. So many of these signs have been recommended in the IRC, uh, 35, uh, have been taken from the RFC 35 as well. Uh, these are, this is a very, uh, typical, uh, road crossing at yields, uh, at yield science where you have to, where there is no signal. Available, you have to yield for pedestrians. That is what that signal says. So, uh, my recommendation would be, you have to go through this IRC very carefully before you start designing for any kind of pedestrian crossings at your art constricts.