喷膜防水层在隧道复合式衬砌中的防水效能模拟试验研究

对丙烯酸盐喷膜防水层在隧道复合式衬砌中的不同工作状态进行模拟与测试，以对其防水效能及影响因素做出评价。通过单层、双层混凝土试验板对防水层及隧道衬砌的局部结构进行了模拟，并通过手动泵进行渗漏水压加载。由试验可见，在单层试验板中没有排水层或排水层不通畅时，较低的水压就能在防水膜后形成渗流通路；在双层试验板中没有排水层或排水层不通畅时，防水膜能抵抗一定程度的渗漏水压；只有在双层试验板中的排水层畅通时，防水膜才能有效地将渗漏水控制在排水层中排走。试验结果表明，衬砌间的挤压应力、防水层的弹性恢复能力、通畅的排水层对丙烯酸盐喷膜防水层在隧道复合式衬砌中的防水效能发挥首要作用。

Simulation Experiment Research on Waterproofing Effectiveness of Spraying-on Membrane in Tunnel Composite Linings

The different working conditions of the waterproof layer of spraying-on acrylate membrane in tunnel composite linings were simulated in tests to evaluate the waterproofing effectiveness and influencing factors of the layer.The waterproof layer and partial structures of composite linings were simulated by single and double shell concrete test slabs,and the seepage water pressure was applied to the slabs with the manual pump.The phenomena can be observed in the tests: low seepage pressures can easily form passageways behind the waterproof layer if there is no drainage layer or the drainage layer is blocked in the single-shell test slab;the waterproof layer can resist higher seepage pressure if there is no drainage layer or the drainage layer is blocked in the double-shell test slab;the seepage water can be controlled and drained away in the drainage layer by the waterproof layer only if there is unblocked drainage layer behind it in the double-shell test slab.The conclusion is that the extrusion presses between primary and secondary linings,elasticity of the waterproof layer and unblocked drainage layer are the vital factors influencing the waterproof layer of spraying-on acrylate membrane in tunnel composite linings.