【摘要】 由于考虑到钢筋混凝土梁弯剪破坏的突然性和试验数据较大的离散性,从设计原则上应该使抗剪的安全度超过抗弯的安全度,规范取抗剪承载力的下限值。保守的设计方法在某种程度上可能会掩盖剪切破坏的某些问题,抗剪承载力实际值的研究非常必要。基于大量的试验数据和拉压杆方法,本文对不同破坏形态下混凝土梁抗剪承载力的平均值进行分析研究,提出了无腹筋梁剪压破坏的极限承载力与压杆角度θ(弧度值)成正比;得出了用压杆角度θ来计算抗剪承载力的计算公式,计算公式形式简洁,并且考虑了纵筋率的影响,与试验数据吻合度较好,有利于抗剪承载力的研究。更多还原

【Abstract】 Considering the suddenness of bending and shear failure of reinforced concrete beams and the large discreteness of test data, the safety of shear should exceed the safety of bending in design principle, and the lower limit of shear capacity should be taken in the code. Conservative design methods may conceal some problems of shear failure to some extent, so it is necessary to study the actual value of shear capacity. Based on a large number of experimental data and tension-compression bar method, the average shear bearing capacity of concrete beams under different failure modes is analyzed and studied in this paper. The ultimate bearing capacity of beams without web reinforcement is proportional to the angle of compression bar(radian value). The formula for calculating shear bearing capacity by using angle of compression bar is obtained, which is concise and considers longitudinal reinforcement. The effect of shear rate is in good agreement with the experimental data, which is beneficial to the study of shear capacity.更多还原