型钢轻骨料混凝土构件钢骨翼缘临界宽度比计算

Computation of critical width ratio of shape steel flange in reinforced concrete with lightweight shape steel aggregate

对型钢轻骨料混凝土(SRLC)构件斜截面抗剪承载力计算模型进行分析,研究钢骨翼缘临界宽度比计算公式和相关影响因素.考虑型钢和轻骨料混凝土界面之间的粘结作用,建立剪切粘结破坏模式下的抗剪承载力.根据剪切粘结破坏和斜剪破坏抗剪承载力相等,推导钢骨翼缘临界宽度比计算公式,结合试验结果对临界宽度比的有效性进行验证.结果表明:当钢骨翼缘宽度比小于临界宽度比时,剪切破坏模式由斜剪破坏控制;反之,由剪切粘结破坏控制;混凝土强度对临界翼缘宽度比的影响最大.给出的钢骨翼缘临界宽度比计算公式可用于型钢轻骨料混凝土梁剪切破坏模式判别和抗剪承载力预估.

Computational formulas of steel flange critical width ratio and its relative influencing factors were studied based on the analysis of the computational model of bearing capacity of shear force on an in- clined section of steel reinforced lightweight aggregate concrete （SRLC） member. The shear bearing capacity in the shear bond failure mode was determined by taking into account the bond effect on the inter- face between steel and lightweight concrete. The computational formula of steel flange critical width ratio was deduced on the basis of equality of the shear bond failure capability with the bearing capacity of in- clined shear failure and its validity was verified by the with test results. The result showed that the shear failure mode would be controlled by the inclined shear failure when the width ratio of steel flange was less than the critical one. Otherwise, by the shear bond failure. The concrete strength wbuld have the biggest influence on the critical width ratio. The proposed computational formula of width ratio can be well used to identify the shear failure mode of the concrete beam with lightweight shape steel and predict its shear bear- ing capacity.