中文摘要：

方钢管膨胀混凝土结构是一种较为理想的钢管混凝土结构。通过对18根方钢管膨胀混凝土短柱的偏压试验研究,考察了方钢管膨胀混凝土结构的基本偏压力学性能。试验结果表明,掺入适量膨胀剂,方钢管膨胀混凝土偏压短柱的极限承载力提高程度可达3%～12%,另外,分析了膨胀剂、偏心率、宽厚比等因素对构件偏压相关力学性能和变形破坏过程的影响,所得结论可供有关工程设计和理论研究参考。

英文摘要：

Square expansive concrete-filled steel tubes（ECFT） are a sort of optimization design for concrete-filled steel tubes（CFT）.Tests on 18 eccentrically compressed square ECFT specimens were carried out.The mechanical behavior of the members under eccentrically compressed load was studied.The experimental results indicated that the ultimate strength of eccentrically compressed square ECFT columns with appropriate expansion agent was increased by 3%~12% as compared with that of ordinary CFT columns.Moreover,the influences of the expansion agent,eccentricity ratio and width-thickness ratio on the behavior of eccentrically compressed square ECFT columns were also investigated.The achievements of the paper could be a reference for the design and the theory study of square ECFT members.