钢筋混凝土板的压力膜效应承载力计算方法

Calculation method of load capacity compressive membrane effect of reinforced concrete slab

基于钢筋混凝土板的压力膜效应受力机理及极限状态下的几何条件,以侧向约束力为中间参数,提出了一种压力膜效应的极限承载力计算方法。该方法基于附加承载力理论,将压力膜效应承载力看作纯弯曲作用下的弯曲承载力和三铰拱作用下的附加承载力之和,采用计算机辅助的程序化算法分别计算可以较方便地获得满足要求的计算结果。设计了一组剪力墙约束钢筋混凝土板,采用侧向约束刚度为定值的水平支座约束试件的侧向变形,试件的极限承载力较屈服线法的计算结果平均提高了38.3%。与其他方法的计算结果对比表明,该方法使用简便,且具有较高的计算精度,适于工程应用。

A new calculation method was proposed to predict the ultimate load capacity of the reinforced concrete slabs under the compressive membrane effect based on its loading mechanism and the geometrical conditions at ultimate state with the lateral restraint load as intermediate variable.The method is according to the theory of the additional load capacity,considers the load capacity of the compressive membrane effect as the sum of the puve bending load capacity and the additional load capacity by the three-hinge arch effect,uses the computer-aided programable algorithm to easily get the required results.A series of specimens of the shear-wall restrained reinforced concrete slabs were designed with the horizontal support with constant lateral restraint stiffness to restrain the dateral deflection of the specimen.The ultimate load capacities of the specimens obtained by the proposed method were on an average 38.3% higher than those calculated by the yielding line method.Compared with the other calculation methods,the proposed method is easy to use and the test data proved its calculation precision suitable for engineering application.