有孔道混凝土局部承压拉压杆模型的受力机理研究

Study on Bearing Mechanism of Local Bearing Strut-and-Tie Model of Perforated Concrete

目前,钢筋混凝土局部承压承载力的计算以经验公式居多,且多以无孔道的情况为主,这表明有孔道局部承压的受力机理研究尚显不足。由此,文章将以拉压杆模型相关理论体系为指导,通过渐进性结构拓扑优化软件与三维非线性有限元分析,对有孔道局部承压问题进行受力机理(分为传力机理和破坏机理)研究。结果表明:有孔道局部承压符合空间桁架传力机理;其破坏始于局压劈裂区的开裂,终止于承压板下陷的崩溃。

Nowadays,the calculation of local bearing capacity of reinforced concrete was mostly based on empirical formulas,and most of them were in the case of no duct.This indicated that there was a lack of research on the bearing mechanism of local bearing with duct.Therefore,under the theoretical system of the strut-and-tie model,through the Evolutionary Structure Optimization software and three-dimensional nonlinear finite element analysis,this paper will study the bearing mechanism(including force transfer mechanism and failure mechanism)of the local bearing of the perforated concrete.The results show that the force transfer mechanism of local bearing of perforated duct was space truss.Its failure starts from the cracking of the local bearing splitting zone and ends with the collapse of the concrete under the plate.