不同箱体形式混凝土密肋空心楼盖受力性能试验

为研究箱体形式对混凝土密肋空心楼盖受力性能的影响，设计制作了1块全现浇空心楼盖板带试件、1块明箱空心楼盖板带试件、1块暗箱空心楼盖板带试件，对3个试件进行静力试验，得到了各试件的破坏形态、荷载 钢筋应变曲线、荷载 混凝土应变曲线、荷载 跨中位移曲线，并对各试件开裂弯矩、极限弯矩进行对比分析。结果表明:预制混凝土箱体与现浇肋梁协同受力性能良好，全现浇板带试件与装配整体式板带试件刚度基本一致；由于现浇肋梁与预制混凝土箱体新旧混凝土结合面相对薄弱，以及板底钢筋不连续，明箱、暗箱空心楼盖板带的开裂弯矩和极限弯矩均低于全现浇空心楼盖板带；各试件开裂弯矩和极限弯矩的计算值与试验值吻合较好。

Experiment on Mechanical Behavior of Concrete Hollow-ribbed Floor with Different Box

Three specimens with different boxes, a cast-in-place slab, a visible-box slab and an invisible-box slab, were designed to study the influence of box on mechanical behavior of concrete hollow-ribbed floor. The failure patterns, load-strain curves of rebar and concrete as well as load-deflection curves at mid-span, were obtained by static experiment. The cracking moment and ultimate moment of specimens were analyzed comparatively. The results show that the precast concrete box works well with cast-in-place ribs, stiffness of cast-in-place slab and assembled monolithic slab are about the same. The cracking moment and ultimate moment of visible-box slab and invisible-box slab are lower than those of cast-in-place slab, on account of feeble interface between cast-in-place ribs and precast concrete box, as well as discrete rebars at the bottom of slab. The calculated values of cracking moment and ultimate moment are in good agreement with the test values.