现阶段钢管混凝土柱推出试验中,核心混凝土应力水平较低,试验并没充分考虑核心混凝土膨胀性对钢管与核心混凝土之间的黏结性能的影响。为研究钢管混凝土柱中核心混凝土膨胀性对钢管与核心混凝土之间的黏结性能的影响,以钢管壁厚和高度、核心混凝土应力水平、长径比及钢管与核心混凝土之间滑动摩擦系数为变化参数,共设计了三组10个圆钢管混凝土柱试件进行推出试验。通过试验得到在不同应力条件下的推出试验中钢管混凝土柱的破坏方式、荷载-位移曲线、推出量和压缩量之间的关系曲线、钢管表面纵向和环向应变的分布规律及钢管与混凝土之间粘结强度。试验研究结果表明:低应力条件下钢管表面的纵向和环向应变都较低,全部测点未达到屈服应变,高应力条件下,钢管表面的纵向和环向应变变化幅度较大,部分测点达到屈服应变;两种应力条件下的荷载-位移曲线变化趋势基本相同,但高应力条件下承载力较高;核心混凝土的膨胀性对钢管与混凝土之间的粘结力有较大影响;通过在钢管内表面涂抹黄油减小钢管与核心混凝土之间的摩擦系数,对钢管与混凝土之间的相对位移影响明显,在高应力条件下,荷载较小时,推出量和压缩量基本相同,但随着荷载的增加压缩量增加比推出量增加速度快。 Many studies of concrete-filled steel tubular (CEST)colimn push-out test, failed to consider the impact of core concrete expansion on the bond performance between the steel ppe and core concrete. This study aimed to examine the influence of core concrete expansion on the bond performance between steel pipe and core concrete, with pipe wall thickness and height、core concrete stress level, aspect ratio and coefficient of sliding friction between steel pipe and concrete core as change parameters. It designed a total of three groups of 10 cotrete filled steel tube column specimens to carry on push-out test. Test results showed Loaddisplacement curve was basically the same trend under this two stress state, but it had a higher carrying capacity under high stress conditions. Under high stress conditions, when the load was small, the amount of the introduction and the amount of compression were basically the same, but with the increase of load, the increase of amount of compression is faster than the rate of the increase of the increase of the amount introduction. Core concrete expansion had a greater impact on the bond performance between steel pipe and core concrete. By buttering steel pipe inner surface to reduce the friction coefficient between the steel pipe and core concrete, it had a clear impact on th relative displacement between the steel and concrete.