盾构隧道防水密封垫长期服役性能预测的室内试验研究

Experimental Study on Prediction of the Long-term Serviceability of Waterproof Gasket for Shield Tunnels

文章研究了盾构隧道橡胶防水材料老化系数的确定方法,并用该方法来预测防水密封垫长期服役下的使用状态。采用哑铃状橡胶试样开展加速热氧老化试验,进行材料基础老化指标的分析;分别用试验结果中相对延伸率和相对弹性模量的试验数据拟合"阿累尼乌斯方程"的"P-T-t三元模型",然后计算橡胶材料的老化系数,预测密封垫长期服役后的性能劣化程度,进而推测防水能力的变化,为后期防水密封垫老化试验做准备。研究结果表明,两个指标中使用相对弹性模量指标拟合方程的效果优于相对延伸率;橡胶100年后的老化系数为36%。

The paper studied the determination method of aging coefficient of the waterproof rubber which will be used to predict of the long-term serviceability of waterproof gasket for shield tunnels.Accelerated thermal oxygen aging experiments were carried out for dumbbell-like sheets to analyze the basic aging properties of rubber materials.Two kinds of experimental data,relative value of extensibility and relative value of the modulus of elasticity,were used to fit.the Arrhenius equation.The fitted equations were used to calculate the aging coefficient of the rubber and predict the long-term waterproof capability of the gasket,which will guide the waterproof experiment of aged gasket.The result of experimental study showes that using relative value of the modulus of elasticity to fit the Arrhenius equation is better,which yields the aging coefficient of a hundred years to be 36%.