Hello everyone. I welcome you for this today's session. I am Ashok Kumar, Assistant Professor, Department of Civil Engineering, WALCHEN Institute of Technology, in this class, we are going to discuss about the transition curves on roads. Learning outcomes. At the end of the session, students will be able to describe the objective of transition curves and select the ideal type of transition curves on roads. Let us understand the function of a transition curves in horizontal alignment. Our transition curve is having a curve of having a varying radius. Why varying radius? You can see here, at the state path, the radius is infinity. And the centrifugal force P equal to 0 because the P, that is the centrifugal force, m e square upon r c, if I put the r value as infinity, automatically the P value is 0, the centrifugal force is 0. And from here onwards, the radius starts decreasing. And we are getting some value at this point r equal to r 1 and r equal to r 2 and r equal to r c, that is a start of the circular curve. We are getting a full designs radius. If I put the value of r equal to r 1, here denominator is lesser. Obviously, the centrifugal force is increasing. So, you can see here, the centrifugal force is increasing up to this point and here onwards it is constant. Now, the centrifugal force is increasing from this point. It means, if you do not have any transition curve in between, if I join the circular curve directly to the state path, having the centrifugal force, it applies a sudden jerk on the vehicle or lateral sway on the vehicle. So, what will happen? A sudden jerk and lateral sway, it causes the discomfort to the passengers sitting inside as well as the steering of the vehicle, the smooth steering of the vehicle will not be able to possibly to turn the steering safely. That is the main, the hazardous will happen without having any transition curve. If I design the transition curve over here between circular and state path, now we can introduce the centrifugal force gradually from this point to this point and this point and here onwards it is constant. So, start of the circular curve, we will be having a transition. Again at the end of the circular curve, we will be having another transition. Now, first application of the transition curve to introduce this centrifugal acceleration gradually from straight path to circular path. So, that they are not be having any discomfort as well as the smooth steering of the vehicle is also possible. Second application of the transition curve is for super elevation. Here the normal super elevation is camber that is 2.5 percent. Now, I want to take this 2.5 percent at the circular path, it is 6 percent or 7 percent depending upon the speed and the radius the super elevation is designed. Here it is 7 percent. So, now 2.5 to 7 percent, I cannot directly increase suddenly from 2.5 to 7 percent. So, this transition length if I use it, I can increase gradually having a suitable rate of super elevation, increase gradually super elevation from 2.5 to 3, 4, 5, 5.5, 6, 6.5 and 7 percent up to the circular path. Again from circular path it is 7 percent. Again from 7 percent to 2.5 percent, another end of the transition curve. So, transition curve will helps you to gradually introduce the super elevation from normal camber to designed super elevation. This is the second application of a transition curve. Third application again widening. At the curve we are depending upon the radius and speed we are increasing the width of the pavement at the curves.  So, from 0 to 0.9 meter again I will be using the transition curve to gradually introduce the extra widening on the pavement. So, this will helps you to introduce gradually the widening on the pavement. Third application is aesthetically it looks very pleasant appearance having a transition curve on the roads. So, these are the overall objective of a transition curves. Now, to fit this transition curve we need to here we can see here that we are shifted the original circular curve for a some distance. So, this is required to set out this accommodate this transition curves on the circular curve we need to shift this distance. So, how to calculate the shift it is given by Ls square upon 24r. So, this r is the radius of the curve and Ls is the length of the transition curve. Let us summarize the overall objective of a transition curve this is used the to introduce the gradually the centrifugal force so that they are not be having any sudden jerk on the vehicle. And turn the steering of the vehicle gradually for its own comfort and safety and gradually introduce the design super elevation and widening at curves as well as it looks very pleasant appearance or aesthetically it looks very good having a transition curves. Requirements of a transition curves radius of the curvature should decrease gradually from infinity to the minimum. So, because at the state point it is infinity and it should goes on decrease at the start of the transition at the start of the circular curve. So, infinity to the designed value rate of change of centrifugal acceleration should be uniform gradually introduced. So, this will take care about the discomfort or undesirable locate oscillations if you are introducing the centrifugal acceleration gradually and uniformly. So, there will not be problem with any discomfort or oscillations or lateral sway. Radius of the curvature should be inversely proportional to the length of the curve from the starting point. So, all these conditions will be fulfilled by spiral. So, spiral is the ideal transition curve where it will take care all these the points to set out in the field. We got different types of the transition curves. We got spiral, laminiscate and cubic parabola. Among all I told you the spiral fulfills the all the conditions. So, why it is fulfilling? For a up to 4 degree we can see here all this spiral laminiscate and cubic parabola the path followed by all this curves are same. But after the 4 degree are more than 9 degree are larger angles we are trying to what will happen the radius is not uniform the rate of change of the radius is not uniform. When the radius is not uniform automatically your the centrifugal acceleration is also not uniform. Other than increasing when the radius starts increasing automatically the centrifugal acceleration starts decreasing. So, that causes the hazardous are accident at that particular location. So, laminiscate and cubic parabola is holds good for smaller angles. But when you go larger angles the spiral fulfills the ideal condition. Spiral or clothite here as I told you the radius of the curve is inversely proportional to the length of the curve. And this will take care about the centrifugal acceleration when the radius is inversely proportional to the length of the curve the rate of change of centrifugal acceleration is uniform throughout the length of the curve. We can introduce the centrifugal acceleration uniformly. And this will take care having designed spiral length we can control the centrifugal acceleration at particular points. So, that is another advantage of having a spiral. And for easily setting out in the field we can set out and we can easily calculation part spiral is easy setting out is easily as well as the execution and construction of the spiral is easy in the construction. And it is given by L r equal to L s into R c the L s is length of the transition R c is the radius. So, that is L s into R c equal to constant c. Bernoulli's lemniscate here as I told you for smaller angles this Bernoulli's lemniscate holds good here is also the radius is inversely proportional to the length of the curve. But the problem is for larger angles higher than 4 degree the rate of change of radius or rate of change of centrifugal acceleration is not constant. So, when there is this is not constant will not able to control the centrifugal acceleration the rate of change of centrifugal acceleration. So, when the radius is not constant when your centrifugal acceleration is also not constant. For smaller angles this holds good cubic parabola again here is also the radius the curve is inversely proportional to this x and here is also this is also a type of the transition curve. But for the radius and the rate of change of radius and rate of change of centrifugal acceleration is not constant when the reflection angle is goes beyond the 9 degree. So, this is not ideally suitable for construction of the highways because this is not the points the ideal transition will not able to when angle is goes beyond 30 degree or higher than higher than 9 degree. So, this will not able to having the transition properties. Now, let us pause the video and try to select the correct answer where the rate of change of radius is constant in which type of the curve whether it is spiral, cubic parabola or Bernoulli's MNISC or all the above. I hope you are able to select the correct answer the correct answer is spiral in the spiral your rate of change of radius and centrifugal acceleration is uniformly introduced. So, spiral is the correct answer. These are the references I have used for presenting this presentation. Thank you.


Good afternoon, everyone, and welcome. Welcome to the Stockswish Show play of the day in Cree. This is a bearish gap. Of course, this is a nice golden gap rated well this morning and had a nice shorting at this morning and actually is setting up here to go lower this afternoon. Every once in a blue moon, you could do a trade in the afternoon. It's not something I do every day. It's not something I even do every month. It might be something I do a couple of times a year. You have to have certain criteria that you're looking for in order to do that and you still have to have risk to reward and target left in the trade to do it. I even actually still think it helps you maybe to have the market with you in the afternoon, but not necessarily. It's really about the gap. Still in all, even in the afternoon. But this is a nice gap here today. It doesn't look like much, but again, this could get some more extension into it this afternoon. Target this afternoon is $40. Let's look at this overall look here. This was a swing entry to go short for longer term trade in the Korean. I'm considering starting a swing trade letter. I don't know when I'd have time to do it, but I knew that this was a core short. And this is, if you did that short there as a swing trade, it's on its way down in here now. Even today, you're up very nicely. From the high of this original gap that happened back here, which was short as a day trade back in April from 5340. The stock is now down today and almost got to 40 bucks. I'm sure a lot of people did not stick with this, even if they shortened this here. Why? It did go to a nice move here in the first couple of days. You could have done it as a quick swing trade. This moved nicely into that move. But in the longer term picture here, Cree is lower. Cree is lower. I said that when I did that gap originally, and I'm even saying this now here today as well. And I'd have to figure long-term targets in here, but $30 is actually realistic in this for a longer-term trade. Not today, but later. Look at the nice doji. This is making them the five turn out, even the 15 minute for this afternoon. So this is waiting for the 20 minute, 20 pre-moving hour. Just squish on top. I'd have been here in the 15 minute. Love the doji's here in the five and in here too. This Cree looks great. Again, 12, 15. You're just going to have to be patient here. Where should this break the low of the day if it's going to this afternoon? Probably 1 o'clock, 1.15, 1.45, 2 o'clock, major reversal time. It's got two by two. And we'll see where it goes. Let's look at the morning play. Beautiful dollar move in the morning. Beautiful. Aggressive entry in the Cree in here. Here's the buck. Again, you're really, the morning is it. I mean, the morning is a time.  Done with your day on a Monday to get a move like that in a gap in a Monday and a quality trade like this in a Monday. You don't always get it, but I will say one thing. It is fall. It is September, September, October, November. It is it. This is the time to trade. If you were going to trade, if you're a day trader, then now is the time. If you're a swing trader, now is the time. This is it. These are going to be huge massive months in here for the stocks to show live trading room. Now is the time to make money and trade. And actually, September is good. September has been good. And we are in the middle of the month, but this has been a good month so far. And earning season has not even started yet. earning season hasn't even started yet, but the fall trading season has. And it is underway and proof positive in the pudding by the money I've made so far since beginning of this month. And it's halfway through. And so you will get gaps like this on Monday, even though you don't normally on normal time periods and earning season, you will in the fall, you will. I think fall is actually the busiest season of the time to trade even busier than spring. But a lot of people like to trade in the spring too. But fall is a major time when people are doing things or taking positions on and off before the end of the year. And and we will see some nice sell offs and some things quality quality gold and gas, which this was today in the cream. So beautiful dollar move in the morning. If you didn't, it got all out fine. If you're back in this for the afternoon, fine. This looks good. I have a high level of conviction this for longer term trade as well, though the perfect entry was not today before today in reference to having to place your stop and a position size yourself, you could not be in this over behind the gap today. But I do know all the areas in here. And this is a nice trade. So we'll we'll see where this ends up today. I'll do a video then at the end of the day to see how this plays out. Beautiful short ahead of this in the morning. Again, I love to trade the morning timeframe and gaps every once in a while. You could watch something for the afternoon. I do know how to take a late trade. You just have to make sure that you are patient with it, put the stop at the right place, give it a chance to go know where you're getting out and and stay with it. Stay with it because you're going to be in a longer term trade for several hours. Whereas the morning, if things happen quickly, you're done in, you know, 10, 5, 15, 20 minutes. That's what I like about the morning. But every once in a while, you can see potential and the target of this from even here is a buck. So nice create in here. Beautiful golden gap today. Played it through in the morning as a nice short. If you want to do this this afternoon, there's absolutely nothing wrong with this. I keep saying is not doing anything wrong whatsoever. Nice longer term shorting free as well. This is still lower on the daily chart. Beautiful free. If anyone has any questions for me, email me and Melissa at thestockswitch.com. There's going to be another golden gap class this month at the end of the month of September 27 to 28. I had a lot of people actually that sent me paperwork to sign up. Depending on the different times, I didn't get some people stuff until Saturday morning. And so I had to process and plan another class date quickly here to get these people in that wanted trade with me this month. So I did out of class for September on the 27th and 28th, because I had to commit to certain dates for people that wanted to sign up this weekend, but didn't get their papers back to me this Saturday morning. And just couldn't get everybody in for the weekend. So wonderful, wonderful bearish gap here in the Kree. Nice look to it. Great look to it. If you want to pre register for the next class, I suggest doing so. And because you want to make sure you get in, I take a limited amount of people every class. And if you miss the cut off, then you're not going to get to do the next one. So if you want to trade here this fall, the next class is September 27 to 28 to learn the golden guy. Once you take the class, you are eligible to join the live trading room and get my calls. There will not be an exception for that. There is never any exceptions for that. I don't make exceptions for anyone. So if you want to trade in the room and get my calls, you have to do the gap class. That helps you as a trader because you know what you're doing when you take the calls. You cannot trade this market and trade gaps and take trades into the open unless you know what to do and what to look for and how to rate the gaps and how to take the entries. Okay, I tell everyone, learn how to do this, learn how to do this, because you're going to want to learn how to do it because there will come a time when I'm not going to run the live trading room. And then if you don't know what I'm doing, you're not going to be able to get the trades. Okay, you have to learn from me how to do this and you can. You can. I've talked to people how to do it and you can learn. And some people are doing it extremely well with me here in the room. So congratulations to everyone that did Decree Today. Beautiful, beautiful, bearish gap. Next cold and gap class is September 27th to 28th. Email me and Melissa at thestockswish.com if you want to sign up. Have a fantastic start to the week, great start to the week for the Stock Swish Show live trading room and for me, Melissa, today. Have a great day, everybody.