Numerical analysis tools for modelling reinforced concrete shear wall buildings subjected to earthquake loadings

Abstract

When it comes to resist lateral loads, shear wall is a preferred structure form. There are two main categories of finite elements to model seismic responses of reinforced concrete shear walls, namely the microscopic and macroscopic elements. These numerical tools suffer from several vital problems, such as accuracy, efficiency, reliability and applicability, which hinder their engineering applications. Both experimentally and numerically, it is shown that the in-plane axial-flexural-shear interaction does exist in wall panels. It is not applicable to simply neglect its effect since it could contribute up to 50% of total deformation for short walls. However, it cannot be well predicted by current macroscopic wall elements yet. Available 1D macro elements, in which heavy use of spring/truss elements is involved, cannot fully reproduce the non-linear shear response/profile along the horizontal direction due to the `plane sections remain plane' assumption which is unavoidable during the process of simplifying a 2D planar problem to a 1D one. Another severe issue is the capability of simulating wall-frame interaction. Although some simplification methods have been proposed for hand calculation, it is still complicated to develop finite element models to handle the interactions between wall panels and beams/slabs by using current macro elements, due to the lack of in-plane rotational degrees of freedom.

This project aims to solve above two drawbacks. The main objective is to develop an efficient quadrilateral shear wall element. The new element should be capable of reproducing coupled in-plane axial-flexural-shear interaction with reasonable coarse-mesh accuracy subjected to high shear stress and allowing straightforward simulations of the wall-frame interaction without any additional configuration.