Response of R/C Asymmetric Community Structures Under Near-Fault Motion

Abstract

Seismic vulnerability of asymmetric structures is repeatedly reported by different seismic damage surveys conducted all over the world. Moreover, it is also pointed out by a number of previous research efforts that such damage is more severe in R/C structures due to progressive strength and stiffness degradation of R/C structural elements. Community structures like auditoriums generally have load resisting elements distributed only near the boundary region of the structures leaving a large empty space at the central region. These types of structures are also having very small natural periods due to there comparatively less height than other type of residential or official building structures. Moreover, most of these auditorium structures generally have similar type of orientation in two opposite side whereas other two sides differs in orientation due to functional requirements which lead these types of structures having unidirectional asymmetry. Investigation of response of such systems under near-fault ground excitation are of great importance as there may be a huge gathering of people inside an auditoriums and amount of energy input to the structural systems will be much more in near-fault ground motions are than their far-field counter parts. On this aspect the present research effort investigates the responses of such uni-directionally asymmetric auditorium like community structural systems under a number of real earthquake ground excitation of near-fault nature and a general trend of behaviour is indicated along with comparison between responses of R/C and steel structures of these types.