钻孔压水试验自动测试技术在某过江隧道中的应用

Application of Automatic Test Technology of Borehole Water Pressure Test in a River Crossing Tunnel

钻孔压水试验是利用勘察钻孔,采用栓塞止水,通过测量水位、水压、流量等相关要素,取得流量与压力曲线特征值,进而推算出渗透性能及岩体的完整性等岩体特征。该方法有测试过程简单,数据可靠等优点,已在国内和国外广泛采用。该项目通过自动测试技术,采用双栓塞止水,对天然气管线重要节点过江隧道工程应用压水试验求取水文地质参数,取得了隧址区围岩的渗透系数及岩体完整性特征,为隧道方案的设计和施工提供了重要依据。预测隧道洞身段主要的岩体粉砂岩和砂岩为弱透水,渗透系数为10^(-5)~10^(-4)cm/s;局部发育的砾岩为中等透水,渗透系数为10^(-4)~10^(-3)cm/s。

The borehole water pressure test is conducted by the survey borehole,using the plug to stop the water.Through measuring the water level,water pressure,flow and other related factors,the characteristic value of the flow and pressure curve are obtained,and then the permeability,rock integrity and other rock mass characteristics are calculated.This method has the advantages of simple testing process and reliable data,and has been widely used at home and abroad.In this project,through the automatic testing technology,the double plugs are used to stop water,and water pressure test is applied to a river crossing tunnel project at the important nodes of natural gas pipeline to obtain the hydrogeological parameters,thus obtaining the permeability coefficient and rock integrity characteristics of the surrounding rock in the tunnel site,which provides an important basis for the design and construction of the tunnel scheme.It predictes that the main rock siltstone and sandstone in the tunnel body section are weakly permeable,and the permeability coefficient is 10^(-5)~10^(-4)cm/s;The locally developed conglomerate is moderately permeable,and the permeability coefficient is 10^(-4)~10^(-3)cm/s.