钢管轻集料混凝土黏结滑移试验研究

为探究钢管轻集料混凝土黏结滑移过程和机理，取钢管的长度和外径为变化参数，设计4个钢管轻集料混凝土柱。通过推出试验，得到试件位移-荷载曲线和相关特征点参数。从黏结破坏强度、黏结破坏位移和位移-荷载曲线等角度分析了长细比和紧箍系数对钢管轻集料混凝土黏结滑移影响和加载过程中钢管外壁的应力变化情况。试验结果表明:在荷载-位移曲线后滑移阶段，紧箍系数越大的试件，钢管与混凝土之间的摩擦力越大；相同长细比的情况下，紧箍系数大的试件，其黏结破坏强度大，黏结破坏强度对应的位移小；在相同紧箍系数的情况下，长细比大的试件，其相应黏结破坏强度对应的位移大；纵向应力随荷载变化正比变化；滑移过程中，钢管对混凝土有较大的环向应力。

Experimental Research and Analysis on Bond Slip of Lightweight Aggregate Concrete Filled Steel Tube

In order to explore the process and mechanism of the bond slip of lightweight aggregate concrete filled steel tube, the length and diameter of the steel tube are chose as the change parameter, and four steel tube light aggregate concrete column are designed. By the introduction of the test, the displacement load curve and the relevant characteristic parameters are obtained. The influence of the ratio of length and diameter on the bond slip and the stress change of the outer wall of the steel tube in the loading process are analyzed from the point of view of bond strength, bond failure and displacement load curve. The experimental results show that the friction force between the steel tube and concrete is greater when the load displacement curve is in the sliding stage and the larger the hoop coefficient is. Under the condition of the same slenderness ratio, the test piece with the large hoop coefficient, the bond strength is big, and the displacement of the bond failure strength is small. In the case of the same tight hoop coefficient, the test piece with the large slenderness ratio, the displacement of the bond failure strength is large. Longitudinal stress varies directly with the load change. In the process of slip, the steel tube has a large hoop stress to the concrete.