砌体填充墙RC框架结构平面内抗震性能有限元模拟

砌体填充墙RC框架结构是我国建筑结构中普遍采用的结构形式,历次地震震害表明填充墙的刚度效应和约束效应改变了主体结构的传力机理,导致整体结构的严重破坏。为了分析其砌体填充墙RC框架侧向承载力和刚度,研究砌体填充墙与RC框架之间的相互协同工作机理和砌体填充墙的开裂模式以及砂浆层的滑移,该文利用三维实体单元和基于表面的粘性接触面模型和摩擦原理,建立一种能够较好地模拟其平面内抗震性能的分离式有限元模型。对一个已有试验分别建立普通有限元模型和分离式有限元模型,二者的分析结果与试验结果的对比表明,分离式有限元模拟方法可以更加准确地预测砌体填充墙RC框架结构的侧向承载力和刚度,并且可以有效地模拟出砌体填充墙的开裂模式,通过塑性应变可以判断出RC构件的失效。

Study on in-plane seismic performance of solid masonry-infilled RC frames

Masonry-infilled RC frame is used widely in our country.In the past earthquake events,the lateral stiffness of the infill walls and their restrains altered the load transfer mechanism of the main structure,and therefore resulted sever structural damage.In order to predict the lateral capacity and stiffness of masonry infilled RC frame and investigate the infill masonry crack patterns and the interaction between the infill wall and the RC frame,a separate finite element method is proposed for simulating the in-plane seismic performance of the infilled RC frame by using the 3-D continuum element and the surface-based cohesive model and the friction principle.This paper established a common finite element model and a separate finite element model respectively for a published masonry infilled RC frame experiment.Comparing the results of the two analyses with the experiment result,it is indicated that the separate finite element model predicts the capacity and the stiffness of the infilled RC frame more accurate.And the proposed model can simulate the crack of the masonry infill effectively.The failure of the RC members can be judged by the plastic strain of the concrete and the steel.