DYNAMIC ANALYSIS OF BUILDING WITH SETBACKS

Abstract

Due to high rise of the cost of material it is customary for designer to design the structure economically. Out of the several methods of analysing the structure economically and attractively against earthquake forces, the best available method is to perform a detailed dynamic analysis of structure. In the present work a computer program is developed based on mode superposition method with which a four storied reinforced concrete building with set back is analysed. The building has four equal bays. The total height and width of the building are 19M and 20N respectively. The same problem is also analysed with the help of SAP IV. For this particular problem the horizontal ground motion recorded at El—Centro May 18, 1940 earthquake is assumed as the source of the input earthquake loading. Results obtained by both the programs are duly compared. With the help of developed program a ten storied building with set back having 30M width and 36,1514 height was also analysed by the timewise mode superposition method as well as with the response spectra method as specified in ISe1893-1975. The results obtained by the time step, IS Code and SRSS were compared. Response of different nodes at different time are also plotted. Forces of different members were calculated and also tabulated.