混凝土板受冲切承载力计算方法探讨

Calculation of Ultimate Punching Shear Strength of Concrete Slabs

基于试验构件的冲切机理和受力特征,采用刚塑性模型和双剪应力三参数强度理论,对四边支承钢筋混凝土矩形板在矩形受力荷载作用下的冲切承载力进行极限分析,求得混凝土板冲切承载力的理论计算公式.在此基础上,考虑混凝土板中抗弯纵向钢筋的作用,提出混凝土板极限冲切承载力的建议计算公式.与试验数据比较表明,该公式的计算结果与试验结果吻合良好.

In this paper,the ultimate punching shear strength of concrete slabs supported on four sides is obtained by using the twin-shear stress three-parameter strength theory.Rigid-plastic model has been adopted and the punching failure of concrete slabs is simplified as a problem of plane strain based on the mechanism of punching shear and patterns of failure of the members.A theoretical formula for calculating the ultimate punching shear strength of such elements is established with theorem of plastic limit analysis.Therefor,a corresponding proposed simplified method is put forward taking account of the action of the longitudinal reinforcement.It is anastomotic compared with experiment.