金鸡峡隧道底板突水处治探讨

Discussion on Disposal of Water Inrush from the Bottom of Jinjixia Tunnel

介绍了金鸡峡运营隧道季节性暴雨期间底板突水病害的发生、发展过程,结合突水段底部结构破损特征、工程地质及相关施工资料,认为突水病害原因是:隧道建设期间对砾岩岩溶认识不足,溶隙空洞仅采取回填处理堵塞了原地下水通道,导致暴雨期间底部仰拱结构在短期高水压力作用下发生破坏,地下水涌入形成病害。水害治理采取“排、堵”相结合的原则,提出增设底部泄水孔、增设路面下横向排水沟、加大中央排水沟断面尺寸、仰拱增配钢筋等综合处理措施。病害治理竣工一年多以来,未再发生任何水害。实践证明,处治效果良好。据此,提出岩溶隧道设计注意事项与运营隧道底板突水病害处治的建议措施。

The paper introduces the occurrence and development of floor water inrush during seasonal rainstorm in Jinjixia operating tunnel.Combining with the damage characteristics of the bottom structure, engineering geology and related construction data of the water inrush section, it is considered that the causes of the water inrush are: insufficient understanding of conglomerate karst during tunnel construction, and the original groundwater passage is blocked due to the backfilling treatment of the karst voids, which results in the destruction of the inverted arch structure under the action of short- term high water pressure during the rainstorm, and the influx of groundwater causes diseases. The principle of "drainage and blockage" is adopted in water hazard control. Comprehensive treatment measures such as adding bottom drainage holes, adding transverse drainage ditches under pavement, enlarging the section size of central drainage ditches, and adding steel bars to inverted arch are put forward. Since the completion of water inrush control for more than a year, no water disaster has occurred. Practice has proved that the disposal effect is good. Accordingly, the design precautions of karst tunnels and the treatment measures of water inrush from floor of operation tunnels are put forward.