川东互层式岩溶山区公路隧道涌水量预测分析

Prediction and analysis of inflow of highway tunnels in interlayered karst mountain areas in the Eastern Sichuan Basin

川东地区互层式岩溶山区由于富水的碳酸盐岩与相对隔水的碎屑岩相互交替穿越,地下水分布不均匀,导致公路隧道施工涌水量预测准确性较低。运用4种解析法公式计算隧道的涌水量,并建立三维数值模型对涌水量进行预测,同时对隧道施工期近2年时间的的实际涌水量进行监测,数据对比分析得到以下结论:(1)不同公式计算的隧道涌水量差别较大,需要根据实际情况判断后选择更为合适的结果;(2)三维模型的建立可以充分的考虑到隧道周边现状条件,使得隧道施工前的初始条件与实际情况更为吻合,计算结果也更具有参考性;(3)三维数值模型可以预测不同工况条件下的涌水量,可以更好的结合实际情况,使得计算结果更与实际结果更为接近。

Due to the alternating flow of water-rich carbonate rocks and relatively separated clastic rocks,groundwater distribution is not uniform in the east of Sichuan basin,which leads to the low accuracy of prediction of water inflow in highway tunnel construction. Four analytical formulas are used to calculate the amount of water flowing in the tunnel,and a three-dimensional numerical model is established to predict the amount of water flowing in the tunnel. At the same time,the actual amount of water flowing in the tunnel construction period of nearly two years is monitored. The data comparison analysis has obtained the conclusion that:( 1) the different formulas calculate the tunnel water inflow is quite different,and it is necessary to choose the more suitable result after judging according to the actual situation;( 2) The establishment of a three-dimensional model can fully take into account the current conditions around the tunnel,so that the initial conditions before the tunnel construction are more consistent with the actual conditions,and the calculation results are also more referential;( 3) The three-dimensional numerical model can predict the amount of water flowing under different working conditions,which can better combine the actual situation and make the calculation results more similar to the actual results.