中文摘要：

采用ABAQUS软件,在合理选用材料本构模型的基础上,对18个偏压中长柱进行全过程分析,考察长细比、偏心率、钢材屈服强度等因素对构件极限承载力及荷载-跨中挠度曲线的影响。分析结果表明：构件荷载-跨中挠度曲线可分为弹性阶段、弹塑性阶段、下降段和平缓段4个阶段。长细比、偏心率和含钢率对构件力学性能影响较大,随着长细比和偏心率的增加,构件的极限承载力迅速下降;增加含钢率可以提高构件的极限承载力;增加混凝土强度可以提高构件的极限承载力,但延性有所降低;随着钢材屈服强度的提高,构件极限承载力提高,但荷载-跨中挠度曲线的弹性阶段几乎不变。

英文摘要：

Eighteen concrete-filled square steel tube columns with inner I-shaped CFRP profiles under eccentric load were analyzed on the basis of choosing the reasonable constitutive relation by ABAQUS. The effects of slenderness ratio,eccentric ratio,concrete strength,steel tube wall thickness and the yield strength on the ultimate bearing capacity and load-midspan deflection curves of the columns were investigated. The load and mid-span deflection curve of the column could be divided into 4 stages,elastic stage,elastic-plastic stage,decline stage and stabilization stage.The results showed the eccentric ratio,slenderness ratio and steel tube wall thickness had obvious effects on the mechanical behavior. With the increase of eccentric ratio and slenderness ratio,the bearing capacity decreased quickly. With the increase of steel tube wall thickness,the bearing capacity increased. With the increase of concrete strength,the bearing capacity increased,but the ductility reduced. With the increase of the yield strength,bearing capacity increased,but elastic stage was almost constant.