集中荷载作用下简支预应力空心板的抗剪性能试验研究

Experimental Study on Shear Behaviour of Prestrssed Hollow Slab with Two Opposite Simple Supported Edges under Concentrated Load

通过4块单块板和4块拼缝板试验,研完了预应力空心板在中置集中荷载作用下的抗剪性能,研究结果表明:预应力空心板的破坏型志主要有4种:(1)冲陷破坏;(2)剪切冲陷破坏;(3)冲弯破坏;(4)纵裂——横弯破坏。影响破坏生态的主要因素是空心板的剪跨比λ。此外还提出了抗剪强度的计算公式,采用该公式的计算结果与试验结果吻合较好,并可与非预应力空心板抗剪强度计算公式相衔接。本研究成果可供修订规范及工程设计参考。

Four single slabs and four joined-slabs which are made by Putting two slabs together side by side are tested in this paper. From the experiments, the shear behaviour of prestressed hollow slabs under concentrated load acting on the centre of width are investigated and the following conclusions are reached: (1) There are four main failure modes in the slabs, which are bursting failure, shear-bursting failure, bursting-flexure failure and Iongitudinal cracking transverse flexure failure. (2) The main factor affecting the failure mode is the shear span to depth ratio of the slab. (3) A formula for calculating the shear capaity of the slab is proposed. The formula can give results which are in good agreement with experimental data and dovetail the formula for calculating shear capacity of non-prestressed hollow slabs. These conclusions can be for reference of engineering design and modification of code.