隧道富水破碎围岩水泥-水玻璃注浆参数研究

The Effect of Cement-Sodium Silicate Parameters for Grouting in Tunnel with Cracked Surrounding Rock

福建某在建隧道围岩破碎,稳定性较差,部分位置有富水溶洞存在。在前期水泥浆灌注无效的情况下,隧道采用水泥-水玻璃(C-S)注浆技术,对富水破碎围岩进行治理。通过室内试验,对不同的水灰比、水泥浆与水玻璃之比以及水玻璃浓度的条件下对比凝胶时间的变化,得到水泥-水玻璃凝胶时间的影响规律。之后选取W∶C=1.2∶1,C∶S=1∶0.6,水玻璃波美度为28°Be′的浆液配比进行现场注浆试验,结果表明水泥-水玻璃具有良好的封堵效果。

A tunnel with cracked surrounding rock is located in Fujian Province. And there also are some karst caves in water bearing stratum. Because of inefficacy of cement grouting in the early stage, this study uses cement-sodium silicate(C-S) for grouting, combined with laboratory test and field test to limit the adverse factors. The main research step is as follows:laboratory test of cement-sodium silicate gelation time:optimize the grouting parameters by changing the ratio of cement and water, the ratio of cement and sodium silicate and the Baume degrees of sodium silicate;field tests:select the ratio of slurry(W∶C = 1.2∶1, C∶S = 1∶0.6, Baume degrees of sodium silicate is 28°Be’) to proceed grouting field tests in tunnel. The results show the grouting has a well reinforce effect.