Abstract：
During construction of the Zhongtianshan tunnel, a developed joint zone was encountered with water pressure of up to 6.3 MPa and a water inflow of 500 m3/h/probing hole, causing a flood disaster in the tunnel. In this context, the principle of "drainage reduction by grouting and depressurizing by dewatering" was adopted. The grouting and dewatering design parameters, the new hole-drilling technology with "high pressure percussion drilling," and the new grouting technology with simultaneous grouting and discharging at the same working face are described in this paper. Prospective effects of water blocking by grouting are achieved based on the analysis of a P-Q-t curve, water inflow in the drilling hole, water inflow in the testing hole, and stability in the testing hole, ensuring the success of tunnel construction.
.Treatment Techniques for an Ultrahigh Pressure Bearing Fissure Water
at a Developed Joint Zone in the Zhongtianshan Tunnel[J] MODERN TUNNELLING TECHNOLOGY, 2013,V50(6): 158-162
2013, Vol. 50 