隧道施工超前地质预报研究现状及发展趋势

 超前地质预报是隧道施工中必不可少的环节，对隧道信息化施工、灾害防治和安全保障具有重要作用。在收集整理国内外研究资料的基础上，总结钻爆法和TBM施工隧道的超前地质预报技术的研究现状。钻爆法施工隧道超前预报技术取得较大进展，涌现出一批专用的反射地震类、电磁类和电法类超前探测地球物理方法、技术与设备，逐步形成定量化探测思想和综合超前预报技术。认为基于多元地球物理信息融合与联合反演理论的综合超前地质预报技术是压制探测多解性、提高预报可靠性的可行有效途径；激发极化技术和核磁共振技术则由于其参数对水量的响应敏感性在定量探测水量方面显示出较好的应用前景。同时，TBM施工环境具有其特殊性和复杂性，少数几项专用探测技术的探测效果无法满足工程需要，总体上处于初步研究阶段，尚没有可用、可靠、有效的超前预报技术。结合课题组的研究特色，介绍3种自主研发的钻爆法隧道超前预报技术的最新进展及其用于TBM环境的可行性，提出了四阶段全过程的隧道综合超前地质预报体系，初步形成基于约束联合反演理论的综合预报方法，在钻爆法施工隧道定量化超前预报方面进行有益探索。最后，对隧道施工超前地质预报的发展趋势及其中的关键问题进行预测，认为以下4个方向是今后研究的重点和趋势：(1) 隧道施工定量化超前预报理论与技术的发展深化；(2) TBM施工隧道超前地质预报技术与装备；(3) 钻孔精细超前探测理论与技术；(4) 实时超前地质预报与施工灾害监测技术。

STATE OF ART AND TRENDS OF ADVANCED GEOLOGICAL PREDICTION IN TUNNEL CONSTRUCTION

Advanced geological prediction has been an essential part in tunnel construction and has played an important role in aspects of informative construction，disaster prevention and safety guarantee in tunneling engineering. The state of the art and the trends of advanced geological prediction in drilling and blasting tunneling and TBM tunneling are summarized according to the available data. Great progress has been made in the advanced geological prediction in drilling and blasting tunneling with the emergence of a set of special methods，technologies and equipments，such as the reflection seismic method，the electromagnetic method and the electrical resistivity method，which gradually led to achieve quantitative detection and form a method of comprehensive advanced geological prediction. The comprehensive advanced geological prediction based on the fusion of multiple geophysical information and the method of combined inversion was considered an appropriate way for suppressing the multiple solutions and enhancing the reliability of advanced prediction. The methods of induced polarization and nuclear magnetic resonance have shown great prospects in the quantitative detection of water because of the sensitivity response of its parameters. Due to the particularity and complexity in the environment of TBM tunnel construction，some special detecting technologies did not meet the requirements of engineering practice which are at the preliminary stage of study and there have been no reliable and effective technologies for advanced prediction available generally. The latest developments in our group regarding three kinds of advanced prediction technology in drilling and blasting tunneling and its applicability to TBM tunnelling were described here. A system of comprehensive advanced geological prediction with four stages was proposed based on the theory of constrained joint inversion. The future studies are considered to be in the following four directions：(1) the further development of comprehensive quantitative detection during tunnel construction；(2) the technologies and equipments of advanced geological prediction in TBM tunnelling；(3) the theory and technology of precision probing at drilling；(4) the real time advanced prediction and construction disaster monitoring.