复杂地质条件下CSAMT法对隧道设计施工的指导意义

摘要

隧道在施工掘进期间,水涌、突泥或坍塌等地质灾害时常发生,使施工受阻甚至威胁施工人员生命安全,是隧道掘进的安全隐患.以汕昆高速公路中河池至百色段地质条件较复杂的巴翁隧道为例,运用可控源音频大地电磁法(CSAMT)对该隧道线路进行了勘查,结合线路地质调查和地层岩性资料划分了岩性分界线以及圈定了各类隐伏不良地质体,并对该隧道开挖可能的潜在隐患给予了科学评论和治理建议,钻探验证了勘察结果的可靠性.CSAMT法可指导复杂地质条件下隧道的优化设计并对开挖过程中的可能的地质灾害进行预防和提前处理,是隧道线路前期勘察有效的技术手段.%The geological disasters such as water fushing、mud bursting or collapse may occur frequently during the excavation of a tunnel,which make the construction blocked and even life-threatening to workers.The paper takes Baweng tunnel whose geological conditions is complicated in Hechi-Baise section of Shantou-Kunming highway as an example,using CSAMT method to prospect the geological body underground of tunnel line.Combining CSAMT results with the geological survey along tunnel line and stratigraphic lithologic data,we could make a good geological interpretation to the lithology interface and unfavorable geological bodies,we also give scientific recommendations for excavation and management of the tunnel,and the prospecting results fitting well with dirlling data.CSAMT method can be used to guide the optimum design of a tunnel under complex geological conditions and to prevent possible geological disasters in the excavation process,it is an effective technology for early prospecting of a tunnel.