Comparative and parametric study on codal provisions of seismic analysis of RC frame structure as per IS 1893-2016 (Part 1) and IS 1893-2002 (Part 1)

Abstract

Considerable improvement in earthquake resistant design has been observed in recent past. The sixth revision of IS 1893 (Part 1): 2016, “Criteria for Earthquake Resistant Design of Structures” have been published by Bureau of Indian Standards recently in December 2016. The new code comprises changes considering standards and practices prevailing in India. The present work aims at studying the comparison of revisions in various clauses of IS 1893 (Part 1): 2016 with IS 1893 (Part 1): 2002 and their effect on Equivalent static method and Response spectrum method. The present work focuses on parametric study of G+3 multistory building with varying the number of storey levels 4, 8, 12, 16 and 20 storeys using ETABS software is performed. The effect of varying storey levels on free vibration and response spectrum analysis is carried out. The different modes of vibrations are observed and natural frequencies, time period are tabulated. The RC structure behave in bending for first few modes and later torsion and then buckling. The first few modes contribute to closely spaced modes with lateral bending, torsion. For increasing number of modes the natural frequencies of the structure increases. The differences in storey displacements, base shear, and storey drift are compared with both codes and the effect of variation is addressed. The base shear increases as number of strorey increases, because of increase in seismic weight and depends upon the value (horizontal acceleration coefficient).