EXPERIMENTAL TESTS AND MODELING ON AXIAL TENSION-FLEXURE BEHAVIOR OF REINFORCED CONCRETE SHEAR WALLS

This paper presents a series of quasi-static tests of four reinforced concrete (RC) wall specimens with aspect ratio of 2.0 subjected to axial tensile forces and lateral cyclic loading. The coupled axial tension-flexure behavior of RC walls is investigated including the failure modes, hysteretic response, strength, stiffness, deformation and energy dissipation capacities. The test results indicate two types of failure modes for the wall specimens, including flexure-sliding failure (for specimens with the normalized vertical reinforcement tensile stress n_s=0.23~0.63) and flexure failure (for specimen with n_s=0.91). The axial tensile force results in significant decrease of lateral strength, stiffness and energy dissipation capacity of the RC wall specimens. The maximum strength of specimen HSW4 (n_s=0.91) is smaller than that of HSW1 (n_s=0.23) by 41%. The ultimate drift ratio of the RC wall specimens ranges from 1.3% to 1.6%, exceeding the inelastic drift limit of 1/100 specified in the Chinese code GB 50010-2010. Using the measured crack width data and Vecchio-Collins equation, the shear-sliding strength capacity degradation along the critical crack surface is calculated, and the mechanism of flexural-sliding failure is revealed. A rigorous finite element (FE) model is developed using VecTor2 software to simulate the coupled axial tension-flexural behavior of RC walls. The FE analytical results agree well with the experimental results, providing accurate prediction of failure modes, stiffness and strength of the wall specimens.