粘钢法加固RC梁受弯与受剪承载力公式的工程应用

Engineering application of flexural and shear bearing capacity formulas of RC beam strengthened by bonding steel plate method

粘钢法是一种常用的加固方法,其设计依据为《混凝土结构加固设计规范》(GB 50367-2013)。首先,以规范为基础,分析了粘钢法加固RC梁受弯承载力公式在不同加固阶段中的应用,推导出了受拉钢板厚度t1与受压钢板厚度t2满足的函数关系,探讨了粘钢法加固RC梁在不同加固阶段的受弯承载力。然后,借助拱形空间桁架模型建立了粘钢法加固RC梁的受剪承载力公式,分析了粘钢法加固RC梁受剪承载力的提高程度。最后,借助有限元分析软件ANSYS研究了粘钢法加固RC梁在弯矩与剪力作用下的破坏形态。研究结果表明:粘贴厚度为4.2 mm的钢板后,RC梁的受弯承载力提高约33%;侧面粘贴厚度为1 mm的钢板后,RC梁的受剪承载力提高约57%。通过对有限元模型不同参考点的时程曲线进行分析可知,相比较未加固RC梁,粘钢法加固RC梁的受弯与受剪破坏程度明显降低,其承载力均有较大的提高。

Bonding steel plate method is a common reinforcement method,and its design is based on Code for design of concrete structure reinforcement(GB 50367-2013).Firstly,based on the standard,the application of the flexural bearing capacity formula of RC beam strengthened by bonding steel plate method in different reinforcement stages was analyzed.The functional relationship between the thickness of tensile steel plate t1 and the thickness of compressed steel plate t2 was deduced.The flexural bearing capacity of RC beam strengthened by bonding steel plate method in different reinforcement stages was discussed.Then,with the help of the arched space truss model,the shear bearing capacity formula of RC beam strengthened by bonding steel plate method was established,and the improvement of shear bearing capacity of RC beam strengthened by bonding steel plate method was analyzed.Finally,with the help of finite element analysis software ANSYS,the failure pattern of RC beam strengthened by bonding steel plate method under the action of bending moment and shear force was studied.The results show that the flexural bearing capacity of RC beam increases by about 33%after bonding 4.2 mm thick steel plate,and the shear bearing capacity of RC beam increases by about 57%after bonding 1 mm thick steel plate on the side.Through the analysis of the time history curves of different reference points in the finite element model,it can be seen that compared with the RC beam without reinforcement,the RC beam strengthened by bonding steel plate method has a significantly reduction of flexural and shear failure,and its bearing capacity is greatly increased.