中文摘要：

为考察在役钢管混凝土界面粘结性能与荷载作用时间的关系,以荷载作用时间段为基本参数,完成了7根圆钢管混凝土试件的推出试验。试验结果表明,钢管混凝土界面粘结力随荷载作用时间的延长而减小。根据试验结果,得出各个试件的荷载-滑移曲线。基于ANSI/ACI 308-1992混凝土养护规程,得出每个试件在荷载作用下的混凝土徐变应变。从损伤力学的角度出发,定义界面损伤变量,推导了混凝土徐变应变与损伤的关系。通过回归得出含损伤变量的界面粘结-滑移本构关系。

英文摘要：

In order to investigate the relation between interface bonding property and loading time of in-service concrete-filled steel tube （CFST）, push-out test of 7 round CFST specimens was carried out by taking time period as basic parameters. Experimental results indicate that the interface cohesive force of concrete-filled steel tube declines with the extension of loading time. Then, load-slip curves for each specimen were obtained, based on experimental results. According to ANSI/ACI 308-1992 concrete curing procedure, concrete creep strain produced by sustained loading for each tested specimen was obtained. Based on damage mechanics, the interface damage variable was defined, and the relation between the concrete creep strain and the damage was derived. Finally, the interface bond-slip constitutive relation including interface damage variable was obtained by regression.