基于风险评价的岩溶隧道综合超前地质预报技术研究

Comprehensive geological prediction based on risk evaluation during tunneling in karst area

在岩溶地区隧道施工过程中,涌水、涌泥(砂)已经成为隧道施工的第一大害。对岩溶水进行准确及时的超前地质预报,是当前岩溶地区隧道设计与施工中亟待研究与解决的关键问题。应用地质学、岩溶学理论对隧道进行地质分析,运用模糊数学模型对隧道不同段落进行突水风险评价,进行风险分级。根据各种物探方法的优缺点和对岩溶水预报的敏感性,结合综合超前地质预报方法、原则,优化了综合超前地质预报的预报方案和流程,提高了岩溶水位置探查的准确性,并在沪蓉西高速公路乌池坝隧道予以实施。施工过程中,严格实施综合超前地质预报技术:通过地质分析和模糊数学模型,把乌池坝隧道划分为具有不同地质灾害风险等级的地段,在不同风险等级地段,制定了不同的预报方案。通过实施该综合超前地质预报方案,成功预报了隧道掌子面前方的岩溶水,证实了该方案的科学性和可行性。

During the construction of tunnels in karst mountain,water inrush and gushing mud（sand） disaster has ranked the first in all the disasters.The exact and timely geological prediction is the critical problem most needed to be studied and solved in the design and construction of tunnels in karst zone.The theories of geology and karstology are used for the geological analysis of the tunnel.A fuzzy mathematical model is put forward to evaluate the risk of different parts along the tunnel,and the risk rank is given.According to the advantages and disadvantages of various geophysical methods and the sensitivity of forecasting karst water,and with the method and principle of the comprehensive geological prediction,the forecast program and process of comprehensive geological prediction are optimized and the accuracy of the position exploration of karst water is improved greatly.And the forecast technology is used during the construction of the Wuchiba tunnel of Shanghai-Chendu Expressway west.During the construction of the tunnel,the comprehensive geological prediction technology is implemented strictly.Through analyzing the geology and the fuzzy mathematical model,different risk rating parts of geological disasters along the tunnel are divided.In different risk rating zones,different programs are enacted.Based on the programs,the karst water is successfully forecast,and the scientificity and feasibility are validated.