钢筋混凝土受弯构件正截面弯剪承载力计算方法

Calculation method of normal section flexural⁃shear capacity for reinforced concrete flexural members

在我国现行《混凝土结构设计规范》(GB 50010-2010)中,受弯矩、剪力共同作用的钢筋混凝土构件的承载力,是按受弯承载力和受剪承载力分别计算的,而截面上实际是弯矩和剪力共同作用的复合受力状态。为此,本文基于混凝土剪压强度理论和截面极限平衡原理,提出综合考虑弯矩、剪力共同作用的受弯构件正截面弯剪承载力计算实用方法。计算结果表明,在受弯构件正截面承载力计算中考虑剪力作用影响后,按现行规范计算的受拉纵筋将出现一定程度不足,建议在承受较大剪力作用的钢筋混凝土受弯构件设计中适当增加纵向配筋。

For a reinforced concrete member under the combined action of bending moment and shear force,its bending capacity and shear capacity are calculated respectively according to Code for design of concrete structures(GB 50010-2010).However,the bending moment and shear force on the specified section are coupled force acting together.In this paper,a practical method for calculating the flexural⁃shear capacity of normal section of flexural members is proposed considering the combined action of bending moment and shear force,and this method is based on concrete shear strength theory and section limit equilibrium principle.The results indicate that the longitudinal reinforcement calculated according to current specifications is insufficient to a certain extent.It is suggested to appropriately add more longitudinal reinforcements in the design of reinforced concrete flexural members bearing large shear force,in order to consider the influence of shear in the calculation of normal section bearing capacity for flexural members.