Numerical prediction of out-of-plane instability in RC walls subject to in-plane cyclic loading

摘要

A numerical model composed of nonlinear shell-type finite elements has been proposed and validated for seismic performance prediction and simulation of out-of-plane instability failure in rectangular RC walls. The plane sections are not enforced to remain plane in this type of model, and the in-plane axial-flexure-shear interaction can be simulated without requiring any empirical adjustment. The element used in the model (curved shell element available in DIANA finite element analysis program) has integration points along the thickness, unlike flat shell elements in which integration is performed in one plane only. This element is consequently able to capture the variation of strain along the thickness and simulate the deformation in the out-of-plane direction. Also, the computational ability of the program allows performance of bifurcation analysis based on the energy consumed by different possible modes of deformation.