压型钢板-混凝土组合楼板的承载能力研究

Study of Load carrying Capacities of 3W DECK Composite Slabs

压型钢板-混凝土组合楼板的承载能力受楼板叠合面的纵向抗剪能力控制。本文通过3组组合楼板的荷载试验,研究了单跨简支组合楼板和两跨连续组合楼板的极限抗剪和抗弯性能。试验结果表明:组合楼板的极限承载能力受叠合面的纵向抗剪能力控制;与简支组合楼板相比,连续组合楼板承载能力有明显提高,跨中挠度显著减小,端部支座剪力出现滑移时与简支板端部剪力值相近,显示了连续组合板的端部滑移与剪力的关系与简支板的情况相似。但与简支组合板不同的是,连续组合板端部出现滑移后,其极限承载能力明显高于相同跨度简支板极限承载力。根据试验结果,得到了组合楼板叠合面纵向抗剪能力的计算公式。在组合楼板的承载力设计中,应对支座端部的竖向剪力进行叠合面的纵向抗剪能力验算,文中提出了连续组合楼板的承载力计算方法。

The load carrying capacities of steel deck concrete composite slabs are governed by the longitudinal shear strength. A series of 3 groups of steel deck composite slab tests were carried out. The ultimate longitudinal shear strength as well as the load carrying capacities for both simply supported composite slabs and continuous composite slabs are studied. The test results show that the load carrying capacities of the composite slabs are governed by the longitudinal shear strength at the shear bond interface of the slabs. Compared with simply supported composite slab, continuous composite slab sustains high load carrying capacity with small deflection in midspan. The shear forces at ends of a continuous composite slab are in magnitude at the onset of the shear bond slip initiation close to the shear forces of the simply supported slab, which suggests that a similar shear bond slip behavior may exist for both types of the slabs. However, the difference is that the continuous composite slab can carry further substantial load even after the shear slip initiation as against the simply supported slab. The longitudinal shear strength of 3W DECK composite slab is formulated as based on a linear regression of the test results. It is pointed out that the longitudinal shear bond strength should be checked for the vertical shear at support ends. Finally, a design method for steel deck continuous composite slab is proposed.