摘要
本文通过对13根不同类型的二阶段受力简支矩形截面钢筋混凝土叠合梁的斜截面破坏试验(共29次)、分析了二阶段加荷的叠合梁在叠合前、后受荷阶段剪跨区的斜裂缝开展过程及破坏特征等受力性能,研究了叠合梁的斜截面强度和计算方法,得出了由于叠合前“荷载预应力效应”等的有利作用,钢筋混凝土叠合粱斜截面强度较之相同钢筋混凝土整体梁,一般可提高约10％左右。 在试验研究和有限元法分析的基础上,本文提出了考虑叠合特征参数a_M=M_1/[M_1]、aN=h_1/h影响的简支钢筋混凝土叠合梁斜截面抗剪强度的设计计算公式。计算公式反映了二阶段受力叠合梁的主要特征,概念明确,对比性强,设计计算较简便,计算结果与试验值符合性较好。
Using two stage loading the strength of the inclined section and method of caculation are studied in this paper. through 20 shear failure tests of the compsite beam, process of development of the diagonal tension cracks and the failure characteristics of the composite beam under two stage loading are anlysed. It may be conclued that the composite beam under two-stage loading is about 10% stronger tham the integrated beam in shear strength.Based on tests and analysis with finite element mothod, a new desingn formula for caculation of shear strength of composite beam is proposed. these formulae show the main characteristics of composite beam under two-stage loading, also they are clear in conception and simple in calculating. The calculated results are reasenable agreement with the experimental deta.
基金
<全国钢筋混凝土结构设计规范>重点课题
关键词
叠合梁
钢筋混凝土
抗剪强度
梁
reinforced concrete beam
two-stage loading
the shear strengrh of inclined section
composite characteristic narameters
