新建长输水隧洞中地下水影响评价分析及措施

Analysis evaluation and measures of groundwater influence in newly-built long water conveyance tunnel

为预防地下水对长输水隧洞施工的影响,本文通过现场地质钻孔资料对隧洞沿线地下水水位、地下水分布、涌水量及危害程度进行了分析研究,特别是对隧沿线裂隙发育、断层及高水头区间裂隙水进行了重点分析。结合多年来设计及施工经验,对地下水影响较大的洞段进行了排水处理、对突水涌泥的区段加设钢支撑、喷C20钢纤维混凝土、加大衬砌厚度等措施,同时还采取超前地质预报,提前排水减压,超前固结灌浆等措施,来确保施工安全。实践证明,采取的排水、支护方案合理可行,保证了后续施工的顺利进行。

In order to prevent the influence of groundwater on the construction of long water conveyance tunnel, this paper analyzes and studies the groundwater level, groundwater distribution, water inflow and harm degree along the tunnel through the field geological borehole data, especially analyzes the fissure development along the tunnel, the fault and the fissure water in the high head interval.Combining with the design and construction experience for years, influence on the groundwater drainage treatment was conducted on the larger tunnel section, adding steel support, in the section of water inrush mud C20 spraying steel fiber concrete, increasing the thickness of the lining, also take advance geological forecast, early drainage decompression, consolidation grouting in advance, to ensure construction safety.Practice has proved that the drainage and support scheme adopted is reasonable and feasible, which ensures the smooth progress of subsequent construction.