方钢管混凝土粘结强度试验研究

Experimental Study of Bond Strength of Concrete-filled Square Steel Tube

为了得出方钢管混凝土构件的粘结强度计算公式,进行了不同长宽比、宽厚比方钢管混凝土柱的轴心推出试验,得到了方钢管混凝土的粘结强度变化规律;总结并分析了各国相关试验,提出了当核心混凝土周边的薄壁混凝土破坏之后试件破坏这一思路,利用弹性力学与材料力学的相关理论,推导了方钢管混凝土粘结强度的半经验半理论公式。分析结果表明:方钢管混凝土的粘结强度受构件宽厚比影响较大,受长宽比影响较小;所得公式的计算结果与试验值吻合良好,为方钢管混凝土粘结强度计算提供了新思路。

To obtain the bond strength calculating formula of concrete-filled square steel tube specimens, push out experiments were carried out under different slendernesses and widththickness ratios, and the change principle of bond strength of concrete-filled square steel tube specimens was obtained. According to domestic and foreign experiments, authors proposed that when the thin-walled concrete damaged, the sample was destoryed. Base on this principle, a semiemprical theory formula was deduced using elastic mechanics and material mechanics methods. Analytical results show that bond strength of concrete-filled square steel tube specimen is more affected by width-thickness ratio, and is less affected by the slenderness. The results of formula match well with those of experiments, which provide a new way to calculate bond strength of concrete filled square steel tube columns.