Analysis Of High Rise Buildings By Using Visco-Elastic Dampers

Abstract

 An earthquake directly affects a structure by increasing the energy within the structural system. A significant portion of this energy can be dissipated by the introduction of structural control systems. Several structural control systems such as passive, active and semi-active control systems are gaining importance nowadays in the earthquake resistant design of structures.  viscous damper (VD) is a type of passive energy dissipation device, which operates on the principle of fluid flow through orifices. This type of damper has found numerous applications in the military and aerospace industry from many years. Recently, in the civil engineering field, high capacity fluid viscous dampers have found commercial applications on buildings and bridges subjected to seismic and/or wind storm inputs. VDs use inertial flows, where oil is forced through small orifices at high speeds, in turn generating high damping force. In the present study, the effectiveness of fluid viscous dampers in reducing the responses of a structure under seismic excitations is evaluated analytically using non-linear time history analysis. A twenty story reinforced concrete structure with square plan is considered in this study. Acceleration time histories of Indian seismic zone III,IV and zone V are used for the analysis. The analysis is carried out using the computer package ETABS 2015. The analysis results confirmed that a significant reduction in the responses such as displacements and other forces is possible with the introduction of fluid viscous dampers and hence it can be used as an alternative to the conventional ductility based design method of earthquake.