陡倾裂隙发育岩层深大竖井突涌水量预测及防控

Prediction and prevention and control of sudden surge water in deep and large shaft in steeply dipping fractured rock formation

为实现对裂隙发育岩层深大竖井突涌水情况的有效防控,统计高黎贡山隧道1号竖井富水花岗岩地层节理裂隙的发育特征,基于现场突涌水情况,采用数值模拟对不同裂隙发育情况下竖井开挖突涌水量预测分析,并探讨注浆堵水的合理参数,提出1种基于节理裂隙岩层竖井数值模型的竖井突涌水量预测分析方法。研究结果表明:竖井涌水量预测分析结果较符合现场情况;在节理裂隙交汇处水压较高,涌水速度激增,且随着节理裂隙密度的增加,涌水量逐步增大,裂隙密度为2条/m时最大涌水量已达337.0 m^(3)/h,已远超现场最大抽排水能力;增加注浆圈厚度或降低渗透系数可控制涌水量,根据依托工程,提出相应堵水参数的控制标准。研究结果可为陡倾裂隙发育岩层竖井开挖突涌水量预测及防控提供参考依据。

In order to realize the effective prevention and control of sudden surge water in deep and large shaft in the fracture development rock formation,the statistics on the development characteristics of joint fracture in the water-rich granite stratum in No.1 shaft of Gaoligongshan tunnel was carried out.Based on the site sudden surge water situation,the numerical simulation method was used to predict and analyze the sudden surge water of shaft under different fracture development conditions,then the reasonable parameters of grouting for water plugging were discussed,and a prediction and analysis method for the sudden surge water of shaft based on the numerical model of shaft in the joint fracture rock formation was put forward.The results show that the prediction and analysis results of the surge water of shaft are more in line with the site situation.The water pressure at the intersection of joint and fracture is higher,and the speed of surge water increases sharply.The surge water increases gradually with the increase of joint fracture density,and the maximum surge water reaches 337.0 m^(3)·h^(-1)when the fracture density is 2 per meter,which far exceeds the site maximum water pumping and draining capacity.Increasing the thickness of grouting circle or reducing the permeability coefficient can control the amount of surge water,and the control standard of the corresponding water plugging parameters is proposed according to the dependent project.The results can provide reference basis for the prediction and prevention and control of sudden surge water in shaft excavation in steeply dipping fractur development rock formations.