预应力混凝土叠合板弯曲性能研究

Research on Flexural Behavior of Concrete Composite Slab with Precast Pre-stressed Panel

为辅助某装配式结构工程的施工,对其预应力混凝土叠合板进行四点弯曲试验,研究了其荷载-跨中挠度曲线、荷载-纵筋应变曲线的变化规律,分析了其开裂荷载、峰值荷载、挠度和破坏形态,并将峰值荷载的试验结果与规范计算结果进行了比较。结果表明:在加载初期,预应力叠合板表现出与整浇板相同的受力特点和变形特征;但是,峰值荷载后,叠合板的叠合面出现裂缝,预制预应力板与后浇板共同工作能力降低。叠合板的受弯承载力的计算结果与实测值吻合较好;在正常使用阶段,底部预制预应力板与上部后浇板可共同工作,不会在界面出现裂缝。

In order to assist the construction of a fabricated structure,the four point bending test was conducted with the concrete composite slab.The load-deflection curve and the load-steel rebar strain curve were studied.The first crack load,the peak load,the deflection and the failure pattern were analyzed.The load bearing capacity calculated by the code was compared to the test value.The results show that at the beginning of loading,the composite slab with precast pre-stressed concrete panel exhibited the same characteristics as the conventional bending element,but after the peak load,the cracks appeared along the overlapping surface,and the collaborative work ability between the precast pre-stressed concrete panel and the post-pouring panel reduced obviously.The load bearing capacity calculated is consistence with the experimental value.At the serviceability stage,the precast pre-stressed panel and the post-pouring panel may work together.