RESPONSE STUDYOF HIGH RISE BUILDING UNDER WIND LOAD

Abstract

Wind is a phenomenon of great complexity because of the many flow situations arising from the interaction of wind with structures. Wind is of the most significant forces of nature that must be considered in design of buildings. The characteristics of wind-induced loads on buildings continuously vary in temporal and spatial dimensions. Adequate design of buildings depends on the success in predicting the actual effects of turbulent wind forces to account for the most critical design scenarios which may occur during a certain design period. Under the action of lateral load, a tall building can subjected to lateral or torsional deflection. Due to this lateral stiffness is a major criterion in the design of high rise building. From the past studies, it is found that to resist the lateral force, bracing system in a frame model is highly economical and efficient method. Wind loading computed from wind tunnel test carried out on square shape of frame model. This thesis is composed of two major parts (1) Experimental study and (2) Response study. In the first part of thesis, square shape model is tested in wind tunnel in order to find differential pressure on the surface of model at 140 pressure points under isolated condition with three different wind incidence angle named as 00, 300 and 600. In the second part of thesis, study is carried out to investigate the behaviour of building under wind load obtained experimentally in first part of thesis. A G+17 frame model having RCC beams and columns of plan area 20m X 20m and first storey height is 4.75m and remaining storey’s height is 3.25m, is subjected to wind speed of 47m/s. And the same model is reinforced with X-bracing system at each corner of the building with an angle of size ISA 200X200X25mm. STAAD PRO software is used to analyze the building model subjected to wind load. The response study includes axial force, moment about both axes and displacement under various wind incidence angle. Behaviour of frame with and without bracings is also compared.