装配整体式结构模具成型结合面剪切性能试验研究

EXPERIMENTAL STUDY ON SHEAR PERFORMANCE OF MOLD FORMING BOND SURFACE OF MONOLITHIC PRECAST CONCRETE STRUCTURE

为提高装配整体式结构中结合面的粘结性能和施工效率,提出一种模具成型结合面。通过Z形直剪试验研究了三种不同成型方式结合面的抗剪性能,主要对比了模具成型和传统成型方式结合面的破坏模式和承载力。结果表明,所有的试件均表现为典型的剪切破坏特征。三种成型方式中,水洗露骨料结合面的抗剪承载力最高,其次是模具成型、凿毛结合面。模具成型与水洗露骨料结合面的抗剪承载力相差1.56%。试件达到峰值承载力前结合面连接钢筋发挥作用较小,界面间抗剪承载力主要取决于粘结力、骨料咬合以及摩擦作用。试件达到峰值承载力后钢筋屈服,随着结合面相对位移的不断增大,钢筋销栓作用和剪摩擦作用主要提供界面间承载力。

In order to improve the bonding performance and construction efficiency of joint surfaces in monolithic precast concrete structures,a mold forming joint surface is proposed.The results indicate that all the specimens show typical shear failure characteristics.Among the three molding methods,the washed exposed aggregate joint surface has the highest shear carrying capacity,followed by the molding and chiseled joint surfaces.The difference in shear carrying capacity between the molded and washed exposed aggregate joint surface is 1.56%.Before reaching peak load carrying capacity,the contribution of reinforcements in the joint surface is minimal.The interfacial shear load carrying capacity is primarily dependent on bonding strength,aggregate interlock,and friction.After reaching peak load carrying capacity,the reinforcements yield,and the dowel action and shear friction predominantly contribute to interfacial load carrying capacity with the continuous increase in the relative displacement of the joint surface.