Published Paper Details:

A nonlinear analysis is an analysis where a nonlinear relation holds between applied forces and displacements. These analyses are generally done for High Rise Buildings. One such structure which is used for analysis in this project is Outrigger structural system. Outriggers are interior lateral structural systems provided to improve the overturning stiffness and strength of high-rise buildings. The main aim of this project is to optimize the position and number of outriggers and compare the time history results to check the feasibility. After Optimization it was found that the optimum position was approximately at the center for all models and optimum number of outriggers for 25, 50, 75 and 100 story buildings were 5, 5, 7 and 10 respectively. The P-? effect also played its role considerably in higher story buildings and it had no role in 25 story building. The reduction in displacement was 50 % in 25 story building and it has increased to 62 % in 100 story building which tells that outriggers are more efficient in high rise structures. Also, shorter buildings have undergone periodic vibration with respect to the acceleration during time history analysis but taller buildings due to longer time period, it took time to transfer the acceleration to top story and they undergo damped oscillation after the end of ground motion which concludes that taller buildings are effective against seismic forces compared to shorter buildings which is why short buildings are designed with much care against seismic forces.