配置500 MPa箍筋混凝土梁在间接荷载作用下受剪性能的研究

Shear behavior analysis of concrete beams reinforced with 500 MPa stirrups under indirect load

摘要:

对3根配置500 MPa箍筋的混凝土梁进行间接加载试验,分析了高强箍筋混凝土梁的受力性能、斜裂缝开展情况以及破坏形态。结合ABAQUS有限元软件研究了剪跨比和配箍率对试验梁抗剪承载力的影响。研究表明,《混凝土结构设计规范》能很好地预测配置500 MPa箍筋混凝土梁在直接加载作用下的抗剪承载力；间接加载梁与直接加载梁相比,抗剪承载力有一定程度的降低,降低因素主要为剪跨比和配箍率；规范中附加横向配筋的构造要求可以有效补偿间接加载作用下高强箍筋梁抗剪承载力的降低。

关键词:钢筋混凝土梁;500MPa高强箍筋;抗剪性能;间接加载

Abstract:

A test of three concrete beams with 500MPa high-strength stirrups under indirect load was performed to analyze the structural behaviors, the development of the diagonal cracks and failure modes under direct and indirect load. Numerical models were established with ABAQUS to study the effect of shear span ratio and stirrup ratio on the shearing capacity of the tested beams. The results show that the shearing capacity of high-strength concrete beams under direct load can be precisely predicted with the ’Code for design of concrete structures’. Moreover, the shearing capacity of the beams under indirect load decreases compared with the beams under direct load due to the variation of the shear span ratio and the stirrup ratio. The detailing requirements of additional transverse reinforcement as the code puts can effectively compensate the shearing capacity reduction of the high-strength stirrups beam under indirect load.

Key words:reinforced concrete beams; 500 MPa stirrup; shear behavior; indirect load