桁架-拱模型用于钢筋混凝土梁的受剪承载力计算分析

依据桁架拱模型理论分析了钢筋混凝土梁的受剪机理并给出了受剪承载力公式，该公式考虑了混凝土的软化效应、拱体作用等因素对钢筋混凝土梁的受剪承载力影响，并结合试验数据对公式中系数进行了修正。当结构材料与原建立规范计算公式时的材料性能差异较大时，规范公式不再适用。而经计算，采用桁架拱理论公式的计算结果与试验结果比值的均值更接近于1，标准偏差和变异系数均较规范公式计算结果小，与试验结果吻合较好。采用美国规范ACI 318-08中构件受剪承载力公式对所收集试验数据进行计算，计算结果表明，美国规范较中国规范保守。研究结果表明：桁架拱理论公式可以用于钢筋混凝土梁的受剪承载力计算。

Shear Capacity Calculation Analysis of Reinforced Concrete Beams Based on Truss-arch Model

According to the theory of truss-arch model, the shear mechanism of reinforced concrete beam was analyzed, and formula of shear bearing capacity was proposed. In this formula, softening effect of concrete and the arch function were taken into account, and the coefficients in the formula were amended with experimental data. When the performance difference between the structural material and the original material is huge, the code formula of shear bearing capacity calculation is inapplicable. After the computation, the ratio of the results calculated by truss-arch model theory formula and the results calculated by the current code formula was close to 1, and the standard deviation coefficient and coefficient of variation were smaller than those of standard formula results, and the results calculated by truss-arch model formula were in good agreement with the experimental results. The collected experimental data was calculated with the shear capacity formula in ACI318-08, and the calculation results showed that United States building code was more conservative than the standard of China. The results indicate that the shear bearing capacity formula based on truss-arch model can be used for computation of shear bearing capacity of reinforced concrete beams.