Correlation between strength and ductility design of slender rectangular shear walls following the fundamental principles of limit state method

Abstract

In high-rise buildings shear walls have performed very effectively as lateral load resisting system. Similar to columns, shear walls being generally subjected to flexure with axial forces should have been designed by P-M interaction charts obtained from the concept of capacity-based-approach. Following the design provisions of IS 456:2000,P-M interaction charts for RC slender rectangular shear walls have already been reported depicting failures within the domain of compression-bending. However, shear walls under seismic effects may fail in tension. In the present work P-M interaction charts have been proposed for slender rectangular shear walls for the entire domain of failure right from pure compression to pure tension following the design provisions of IS 456:2000. Quantification of ductility values to assess the seismic performance of shear walls designed as per Indian standards have been very scarcely reported. In the present work curvature ductility of rectangular shear walls have been quantified following the fundamental principles of Limit State Method and presented in the proposed P-M interaction charts. This can enable designers to assess the strength and ductility of shear walls simultaneously. The present study has indicated that ductility of shear wall failing in pure bending has been found to be maximum when designed with minimum percentage of vertical reinforcement (0.25). Damage assessment of shear wall sections as per Performance-based Criteria of ASCE 41-13 has indicated that the minimum vertical reinforcement percentage (0.25%) specified in IS13920:2016 requires modification to restrict the damage within the collapse prevention stage.