双面叠合试件界面抗剪性能试验研究

Experimental study on shearing performances of adhesive interface of double-superimposed specimens

摘要:

叠合板式剪力墙结构是一种新型的装配式结构体系，已经在国内中低层建筑中推广应用。对于叠合剪力墙结构，叠合面抗剪性能是保证其整体工作的关键；界面连接钢筋形式对其抗剪性能的影响同样重要，目前相关试验研究较少。通过6个双面叠合试件剪切性能试验，研究不同界面连接钢筋形式下叠合面的抗剪特性。试验结果表明：双面叠合构件均发生叠合面的剪切破坏，叠合面的裂缝出现过程并不同步，直到叠合面裂缝出现，叠合试块整体性保持良好；叠合无筋构件呈明显的脆性破坏特征，破坏过程中改进的箍筋连接构件的延性优于传统的桁架连接构件；通过理论分析确定叠合面的破坏机理：新老混凝土界面的极限抗剪强度由混凝土粘结力，摩擦力和界面钢筋的销栓力共同作用，然而极限状态时界面的粘结力已经有一定程度的破坏，在计算极限承载力时并不能用三者的最大值简单相加。

Abstract:

The superimposed shear wall is a new assembly-type RC structure, now the superimposed shear walls are applied to medium and low-rise buildings in China. The shearing performances of adhesive interface is crucial in developing a monolithic action for superimposed shear wall; Different types of connecting reinforcement at the interface also influence the shearing performances, there has been no experimental study on the mechanical behavior of adhesive interface. The shearing performances of adhesive interface under different types of connecting reinforcement were analyzed through six double-superimposed specimens. The results showed that shear failure of the interface was the cause of failure of double-superimposed specimens, but the crack formation and development in the two interface was not in synch, the double-superimposed specimen kept good integrity until cracks began to appear. The failure of non-reinforced specimens was brittle, during the process of failure, the improved specimens in which the type of connecting reinforcement is stirrup taken on better ductility than the traditional ones in which the type of connecting reinforcement is truss bar; The ultimate shear strength of the interface was determined by adhesion of interface, shear-friction and dowel action of shear reinforcement, however, adhesion of interface had been destroyed in a certain extent under the limit state, the ultimate bearing capacity of double-superimposed specimens was not simply by summarizations of maximum of three parts.