Design of R.C.C structure using direct displacement based design

Abstract

In recent years, design emphasis is shifting from “Strength” to “Performance”. Structures designed with current seismic design codes and standards, should be able to satisfy specific performance level, defined as life safety performance level, for a specific intensity of ground motion. However, economic losses and occupancy interruptions are not provided (i.e. human lives are protected, but the damages are not limited which may not be economic to repair, the period for re-occupancy is not given). In addition, although life safety performance level is obtained for different structures, the concept of uniform risk is not satisfied (i.e. the response of various structures is different in terms of damages for the same earthquake hazard levels) Direct-Displacement Based Design (DDBD) approach, proposed by Priestley for structures, is one of the simplest design approaches, widely accepted by researchers and it is based on PBSD approach. In DDBD approach maximum displacement in inelastic deformation of the structure is considered, and in contrast with Force-Based Design (FBD) approach, displacement response spectrum is used for obtaining base shear force. In this study it is proposed to evaluate DDBD with reference to Indian scenario, in consistence with IS codes and practice. Keywords—Force Based Design, Direct Displacement Based Seismic Design, ETABS 2016, IS 456-2000, IS 1893-2002.