笼模钢筋混凝土柱抗震性能试验研究

Experimental study on seismic performance of integrated RC columns with reinforcement cage and formwork

采用钢筋笼与周边预制混凝土薄板模壳连接形成一体的中空的笼模构件,在施工现场安装后一次性浇筑笼模构件中空腔体内的混凝土,形成完整的笼模钢筋混凝土构件。该新型笼模钢筋混凝土构件与传统钢筋混凝土构件的主要区别是:箍筋采用成型格网箍筋,笼模构件的模壳混凝土与中空腔体内的混凝土存在二次结合面,构件纵筋采用100%搭接方式连接。为研究笼模钢筋混凝土柱的抗震性能,进行了笼模钢筋混凝土柱和传统钢筋混凝土柱在恒定轴压力下的往复加载试验对比,研究试件的破坏形态、承载力和延性以及钢筋应力的发展过程。研究结果表明:笼模钢筋混凝土柱的破坏形式、承载能力和延性与传统钢筋混凝土柱基本一致,刚度略有提升,两者的受力机理没有明显差异;笼模钢筋混凝土柱可以按传统钢筋混凝土柱的计算原理和方法进行设计计算,提出的计算公式结果与试验结果基本吻合。研究成果可以作为笼模钢筋混凝土柱工作性能评价与工程设计的理论依据。

The reinforcement cage is connected with the surrounding prefabricated concrete shell to form a hollow component.After installation at the construction site,the concrete in the cavity of the component is poured at one time to form an integrated component.The main differences between the new integrated component and traditional RC component include the following that the prefabricated welded grid stirrups are used,a secondary interface appears between the concrete shell and the concrete in the cavity and the longitudinal reinforcement is overlapped connected by 100 percent.In order to study its seismic performance,reciprocating loading tests under constant axial pressure for integrated RC columns with reinforcement cage and formwork and traditional RC columns are carried on.The failure mode,bearing capacity and the development of strains in reinforcement were analyzed.The results indicate that the failure mode,bearing capacity and ductility are basically the same,the stiffness of the integrated RC columns is slightly improved,and there is no obvious difference in the stress mechanism between them.The integrated RC columns can be designed and calculated according to the calculation principle and method of traditional RC columns,and the calculated results of the formula proposed are basically consistent with the experimental results.The research results can be used as the theoretical basis for the performance evaluation and engineering design of integrated RC columns with reinforcement cage and formwork.