方套圆中空夹层不锈钢管混凝土短柱轴压承载力有限元分析

Finite element analysis of bearing capacity of concrete-filled double skin steel tubular short columns with square external stainless steel tube under axial compression

为了研究方套圆中空夹层不锈钢管混凝土短柱轴压承载力,采用Rasmussen本构模型,基于试验建立基准有限元模型,以空心率、不锈外钢管厚度、混凝土与内钢管强度等为主要影响参数开展有限元分析,提出了该类型结构承载力修正计算简式。分析结果表明:研究参数范围内,内钢管强度对结构受力影响不大;混凝土强度、不锈外钢管厚度与承载力呈线性正比关系;采用高强内钢管中空夹层结构承载力随空心率加大先增后减,空心率0.45时承载力最高;提出的修正计算简式可较好预测结构承载力。

In order to investigate the loading performance of concrete-filled double skin steel tubular short columns with square external stainless steel tube under axial compression,Rasmussen constitutive model is adopted and establish the finite solid element model.The main parameters of hollow ratio,outer stainless steel tube thickness and concrete strength are investigated,and the simplified equation is provided.The research results show in the range of study parameter,the strength of inner steel tube has little effect on the bearing capacity and the concrete strength and outer stainless steel tube thickness are approximately linearly proportional to the ultimate bearing capacity;the bearing capacity of concrete-filled double skin steel tubular short columns with high-strength inner steel tube increases firstly and then decreases as the hollow ratio increases,and the bearing capacity is the highest with the hollow ratio of 0.45;the simplified equation can better predict the ultimate bearing capacity of CFDST short columns with square external stainless steel tube under axial compression.