STRUCTURAL INFLUENCE OF SHEAR WALLS ON PLANE FRAMES

Abstract

High rise buildings have become one of the impressive reflections of today's civilisation. There are three major factors to consider in the design of such structures: strength. rigidity. stability. The strength requirement is the dominant factor in the design of low-height structures. However as the height increases, the rigidity and stability requirements become more important. and they are often the dominant factors in the design. There are basically two ways to satisfy these requirements in a structure. The first is to increase the size of members beyond and above the strength requirements. However this approach has its own limits, beyond which it becomes either impractical or uneconomical to increase the sizes. The second and more elegant approach is to change the form of the structure into something more rigid and stable to confine the deformation and increase stability. Wall — frame system is one such and most commonly used building system in the storey height range of 20 to 40 stories. Locating the shear — wall in the frame as well as using the right section of it can do further improvement in its performance by improving the rigidity and stability of the entire structure. In the present study, an effort has been made to see the effect of location and size of the shear wall in a real life building frame, forming part of an office complex, subjected to gravity loading and lateral loads (due to EQ and Wind). A large number of computer programs. based on stiffness matrix method are available for analysing the wall — frame structures. SDABS is one such program, used to analyse the frames considered in this study. Various combination of shear — wall and frame has been compared for two parameters; • drift and stresses in the columns. Total drift and inter-storey drift has been taken for drift comparison. To take into account the combined effect of axial-force and moment, steel requirement for various cases in different columns have been compared. Results have been presented in tabular fashion as well with the help of graphs.