Analytical study on residual displacements in reinforced concrete cantilever walls under cyclic loading

The experience of large earthquakes in the last decades has indicated that reinforced concrete structures under large inelastic deformations are also likely to retain considerable residual displacement. The presence of large residual displacements leads to undesirable final performance. Therefore, the development of methods to predict residual deformation in reinforced concrete structures represents an important challenge. The objective of this study is to evaluate the progress of residual deformations in flexural-dominant cantilever walls subjected to cyclic loading. Two types of walls were examined in this study: one (BC) with boundary columns and the other (NC) without any, but with confinement at the sides. Nonlinear finite element analyses were used to assess the residual displacements in the concrete walls. The finite element models were able to capture well enough the cyclic behavior and the residual deformation of the studied walls. A parametric analysis was carried out for some parameters such as axial load, boundary confinement reinforcement and boundary reinforcement ratio. Furthermore, the effects of boundary columns were also discussed. The results showed that the axial load level on the walls had a substantial influence in the magnitude and progression of residual deformations. It was observed that boundary reinforcement content also affected the progression of residual drifts. On the other hand, it was noted that spacing of confinement reinforcement has little influence on formation of residual drifts.