Earthquake Analysis by Providing Outriggers with Belt Truss System to Buildings

The detailed study is to understand structural behavior of the high rise building with lateral load resisting system under seismic loading is essential for appropriate design and their better performance. In high rise buildings the lateral loads are major concern like earthquake or wind. These are resisted by introducing a system of coupled shear walls and bracings in the structure. But in very tall buildings this lateral stiffness is not enough to resist the lateral loads and hence the introduction of the outrigger beams between the shear walls and external columns is the only solution to provide sufficient lateral stiffness to the structure. The outrigger is commonly used as one of the structural system to effectively control the excessive drift due to lateral load, so that, during small or medium lateral load due to either wind or earthquake load, the risk of structural and non-structural damage can be minimized. For high-rise buildings, particularly in seismic active zone or wind load dominant zone, this system can be chosen as an appropriate structure. The objective of this thesis is to study the outrigger location optimization and the efficiency of each outrigger which is used in the structure. In 60−storey three dimensional models of outrigger with belt truss system is subjected to earthquake load are analyzed and find the natural time period, frequency, base shear, storey drift, lateral displacement reduction related to the outrigger and belt truss system location. The modular analysis for outrigger with belt truss system has been carried out as the thesis.