【摘要】 某铁路隧道在施工期间发生了涌水突泥等地质灾害,为了迅速查明隧道内涌水与隧址区暗河是否存在连通关系,采用了示踪实验的方法:利用NaCl作为示踪剂,在暗河入口处投放,在隧道内三处不同位置采集水样标本,使用硝酸银滴定法识别水样中氯离子的含量,通过合理计算示踪剂投放量与科学设置采样间隔及采样时长,对隧道内涌水与隧址区地下暗河的连通关系进行了定量分析。研究表明:地下暗河对隧道内涌水的补给时间不足10 min,流速略大于63 m/min,水力梯度为0. 193 3,为该隧道的地质灾害处理提供了科学客观的依据。示踪实验方法具有快捷方便、操作简单与工作效率高等优点,在我国西南喀斯特地貌岩溶发育区域铁路隧道勘察领域中具有广泛的应用前景。更多还原

【Abstract】 A large karst cave is discovered during the construction period,and geological disasters such as water and mud gushing are generated. Commissioned by the construction unit,in order to quickly determine the connection between the gushing water in the tunnel and the dark river in the tunnel area,the author adopts the tracer experiment method,using sodium chloride as the tracer,placing it at the entrance of the dark river,collecting water samples at three different locations in the tunnel,and identifying the chlorine content by silver nitrate titration. Quantitative analysis of the connection between the gushing water in the tunnel and the underground dark river in the tunnel site area is carried out by reasonably calculating the tracer dose and scientifically setting the sampling interval and sampling duration. Studies have shown that the supply time of the dark river for the gushing water is less than 10 min,velocity of flow is slightly larger than 63 m/min,and the hydraulic gradient is 0. 193 3,which provides a scientific and objective basis in processing geological hazards of the tunnel. Tracer experiment method is quick and convenient,simple in operation and extremely high in work efficiency,and has broad application prospects in the field of railway tunnel exploration in the karst development area of southwest China.更多还原