隧道施工对水库安全的影响分析

Analysis on Influence of Tunnel Construction on Reservoir Safety

结合山岭隧道下穿深圳梅林水库实际案例,采用有限元模拟开挖施工中隧道的安全稳定性,以及开挖对水库的影响。分别按照完全排水施工工况和堵水限排施工工况进行分析,研究了隧道开挖的初衬变形,运营阶段二衬的安全性和水库在不同施工工况下的变形。水库在不同排水施工工况下的变形趋势不同:采用完全排水工况下变形较大;采用注浆限排的工况下变形较小。对此,推荐采用"堵水限排"施工方法,开挖时对掌子面和洞圈一定范围土层进行注浆。

Based on the actual case of a mountain tunnel passing through Meilin Reservoir in Shenzhen,the finite element method is used to simulate the safety and stability of the tunnel,and the influence of excavation on the reservoir during the tunneling construction.According to the construction conditions of complete drainage and water blocking drainage restriction respectively,the deformation of primary lining in the tunneling stage,the safety of secondary lining in the operation stage and the deformations of reservoir under different construction conditions are analyzed and studied.The deformation trend of the reservoir under different drainage construction conditions is different.The deformation is larger under the condition of complete drainage,and smaller under the condition of grouting and drainage restriction.Therefore,it is recommended to adopt the construction method of"water blocking and drainage restriction".During excavation,the grouting shall be carried out on the tunnel face and the soil layer within a certain range of the tunnel circle.