OPTIMUM OUTRIGGER LOCATION IN OUTRIGGER STRUCTURAL SYSTEM FOR HIGH RISE BUILDING.

Abstract

In modern tall buildings, lateral loads induced by wind or earthquake are often resisted by a system of coupled shear walls. But when the building increases in height, the stiffness of the structure becomes more important and introduction of outrigger beams between the shear walls and external columns is often used to provide sufficient lateral stiffness to the structure. The outrigger and 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, 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 when three outriggers are used in the structure. In 40−storey three dimensional models of outrigger and belt truss system are subjected to wind and earthquake load, analyzed and compared to find the lateral displacement reduction related t o the outrigger and belt truss system location.