 at planning stage. This is Professor C. G. Konapuray, Department of Civil Engineering, Washington Institute of Technology, Sulapur. So, this is the learning outcome for this session. At the end of this session, student will be able to apply the earthquake resistant measures at planning stage of structure. Now, what are the measures we will discuss in this session. The measures shall be taken during the planning stage itself for following features. What are the features? First is site selection. Second is the plan of the building and plan of the building, why it is important. The behavior of the building which is governed by plan that is discussed in this second feature. Third is shape of the building or structure in vertical direction of building. Third is the projection and overhangs for the structures and last is most important thing is the foundations of the building. So, these are the features which we will discuss which are required at the planning stage only. Now, first is site selection. Now, we can see here there are two diagrams and most important thing is the building is shown and slope is shown. Now, what is important in this, this building should be sufficiently away from steep slope. So, this is a slope, steep slope whenever any building is to be constructed on the slope. First you chip up that slope make it horizontal level on firm ground you should construct your building. Most important thing is explained in this sketch that is the foundation should rest on uniform soil. Here you can see firm soil or hard strata here it is filled up or reclaimed soil. So, there are two types of soil on which the building is supported. So, this foundation is resting on two different media medium. So, which is not expected. So, do not go for these types of sites where there are two types of soils this is one thing. And second thing is that from steep slope your building should be away from that steep slope. Now, the site itself is there if we cannot change the site if we cannot there is no scope for the selection of the site. And firm soil is also there and filled up or reclaimed soil is also there. Then in that case what major we should take for that the major is explained in this third diagram. Already there are two diagrams which we are explained in earlier slide. Now, what is to be done on firm soil the raft foundation is provided for this building. For remaining soil this reclaimed soil the piles are taken or raft and pile type foundation the combination is taken and those piles are anchored or end buried peered on this firm soil. So, this remedial major is required for this type of soil site. Now, the second planning feature is plan of the building. Now, especially in public buildings different our shapes are used like I shape, H shape, T shape, L shape, U shape and the X shape. These shapes are used for the public buildings in generally in which the length and width of the extent of the building is very high. So, but what is the problem in that these buildings are asymmetric and this asymmetry should be avoided in the earthquake. Why? That asymmetric building under boat torsion extreme corners are subjected to very large earthquake forces. So, because of this only we have to avoid these types of plans. What change or what major we should take here that the separation joints for this type of plan T plan you can separate these two parts means this web and flank that we can say in case of T plan. So, you separate it to separation joints should be provided and we separate these segments from each other. Why is it so that is explained in this slide. Now, this explains you the behavior of asymmetric building during the earthquake. So, this is earthquake shaking and the inertia force that acting on this building this is yel type of plan and you can see here this behavior this is the width of this section this segment and along that width there vibrations will be there sway is there and this is the length of this segment. So, the length of this segment and width of this segment in both these two directions the inertia forces act that is why fatigue will develop and your structure will fail here only. What is the expected now you separate this length and these two portions these two parts. So, along its width this part will sway along its length this part will sway and there will not be any fatigue there will not be any failure here that is why we should provide the separation joint. Now, this is the next feature. So, at planning stage we must adopt this especially elevation while giving the elation treatment or while making the plan or building in such a way that we should get a very good elevation. Proper care is required that the shape in vertical direction of the building that must be followed by this major or major should be taken while planning the building in vertical direction. Now, let us see this building height this h is height b is width of the building and h by b ratio must be less than 4 why if we make this h by b more than 4 you will get very high rise building or very slender building. So, slender buildings very slender building should be avoided. So, efficient width is required for that much height that is the important concept in this ok. Next thing is this type of building ok here cross it shown means we are do not go for these types of vertical direction or elevations ok. What is here? Here the mass of the building is some x here it is x 1, x 2, x 3 means the mass of the building is increasing as height is increasing or we can say that this entire building will act as inverted pendulum and that inverted pendulum type building is unstable because load path is little complex in this case. So, this cantilever will act its load on this vertical member again that will transport through moment and rotation. So, that is not expected and the inverted pendulum is always very risky for the stability point of view. So, what is expected you should go for this type of arrangement. So, your base width must be higher and as you go towards height your building mass or extent must reduce that is more expected. So, most important point all in all these three is sudden change in the lateral stiffness should be avoided most important. So, sudden change is there this is the change in the stiffness here stiffness here is also stiffness ok. So, whatever may be the plan, but in vertical direction we should avoid the sudden change in the stiffness. Again next these four slide diagrams are explaining you what to be done what shall be avoided. This is a plaza type or tower type of building here you can see the lateral stiffness of this segment this portion is some which is having some amount x let us consider. As you go towards this tower the lateral stiffness of the building is suddenly change at this corner. So, the sudden change in the lateral stiffness is not expected in the earthquake resistant structures probably the earthquake may hit this corner because there is a sudden change in the stiffness. For this plan or this vertical direction is also same thing is expected what we should do we should provide the separation here. Means structurally there are three part, but functionally these are as it is required for serving the purpose of functionality. Provide the separation joint make the structure separate structurally. Now, I am having this question now for all of you please pause the video. Why inverted pendulum type buildings are in unstable? There are four options A, B, C, D. Now just pause the video think of that and give the answer. The answer is B that is the sudden change in lateral stiffness that is making your building unstable. Next thing is projections and overhangs of the building. Now let us see this configuration first avoid long projected balconies. So, cantilevers length of the cantilever should be moderate not large this is explained in this. In next sketch large position should be avoided. So, here projections are there beyond your base or ground story of the building. This should be avoided and third is floating column should be avoided. So, most important thing is that the very favorable practices by the several structural engineers the floating column the column is taken from the B. So, that must be avoided. These three things are not accepted expected in the earthquake resistant design or structure. So, large overhangs projects and floating columns attract large earthquake forces they are of likely to damage and collapse. Damage that is expected within case of the cantilevers and overhangs. So, definitely there will be collapse and that must be avoided in the earthquake resistant structures. Now your third sorry last thing is that the foundations in for the building. Most important thing is your foundation or building actually liquefiable soil we should avoid, but if that is not possible then we have to go for some remedial measure for that. So, what is happening in liquefiable soil if you observe this diagram the your building is miserably sinking and that is with differential settlement for in the liquefiable soil. Next thing for a foundation is to be taken for those types of soils what is to be done we should go for rough foundation. So, rough foundation that will give you it may be liquefiable soil, but it will give you at least equal settlement. Next thing is that one more remedial measure for that foundations in liquefiable soil you should provide piles for that and anchor those piles up into the firm ground. So, this is liquefiable soil continue the pile up to the hard strata and anchor it your building will be stable. These are the references for this session. Thank you.