寒区隧道防水材料长期性能研究

为更全面了解寒区隧道防水材料长期性能, 以赛里木湖隧道为依托, 选取EVA防水板分别在0次、 25次、 50次冻融循环条件下开展了室内拉伸、 低温及顶破试验, 研究了其作为寒区隧道防水材料的工作性能. 结果表明: 冻融循环对EVA防水材料的纵横向拉伸强度、 纵横断裂延伸率、 顶破强力和顶破延伸率有着较明显的影响, 即随着冻融循环次数的增加, 这些指标均降低, 且有随着循环次数的增加降低幅度有增大的趋势, 这说明冻融循环对材料性能的负面影响很大; 冻融循环对EVA的低温抗裂性能基本没有影响.

Study of Long-term Behaviours of Waterproofer in Cold Region Tunnel

In order to understand the behaviors of waterproofer used in cold region tunnel,Sayram Lake Tunnel was chosen to be an object.EVA waterproof board was chosen to do laboratory test,including tension test,low temperature test and bursting test under freeze-thaw cycles of 0,25 and 50,searching the board’s behaviors as waterproofer working in cold regions.It is found that the number of freeze-thaw cycles has great effect on EVA’s vertical and horizontal tensile strength,vertical and horizontal fracture elongation rate,bursting strength and bursting elongation rate.As the cycle number increasing,the above behaviour’s indexes decrease,and as the cycle number increasing,the decreasing amplitudes increase as well,showing the cycle number has great negative effect on the waterproofer.However,freeze-thaw cycle has less effect on anti-cracking of EVA in low temperature.