Concurrent Effects of the Shear-Lag and Warping Torsion on the Performance of Non-Rectangular RC Shear Walls

This paper aimed at analytically investigating the simultaneous effects of the shear-lag and warping torsion on the performance of non-rectangular reinforced concrete (RC) shear walls. Under the concurrent action of shear and axial loadings, the induced warping deformation due to the shear-lag as well as the warping torsion has been accounted for in the elastic region. On the strength of the minimum potential energy principle, a general formulation has been derived for the stress distribution of non-rectangular RC shear walls. By introducing the appropriate geometrical assumptions, the established formulations have then been re-written for conventional T-, U-, and L-shapes RC shear walls. The veracity of the results is ascertained through a comparative study employing finite element simulations for a U-shaped wall, and good agreement has been achieved to an extent that the proposed analytical formulation is capable to, respectively, predict the axial deformation and stress distribution with an accuracy of 95 and 90%. Also, the findings for the U-shaped wall indicate that the shear-lag can significantly affect the axial stress distribution and cracking load, and neglecting the influence of this phenomenon can lead to an inaccurate and a non-conservative design. Moreover, the contribution of the shear-lag and warping torsion has separately been highlighted for the U-shaped RC wall considered in this study.