武汉地铁二号线越江隧道勘察与施工关键问题

Reconnaissance and Construction Key Issues for the Cross-river Tunnel of Wuhan Subway Line No.2

武汉地铁二号线越江隧道勘察设计和施工过程中存在若干工程地质问题和施工重难点,主要有两岸有害气体、浅层砂土是否液化、盾构机障碍物和江中联络通道冻结法施工等。围绕如何正确评价及合理解决上述关键问题,做到即要极大降低施工风险又需有效避免工程浪费,通过标准贯入试验、地下水流速流向测试、有害气体探测等原位测试方法,结合地质学理论分析,从综合液化判别、地下水参数取值、障碍物和有害气体地质预测及工程处理措施等多方面提出科学建议,为设计和施工提供了详实的地质依据。

During the survey, design and construction process of the cross-river tunnel of Wuhan Metro Line 2 there were a number of engineering geology problems and serious and difficuh construction issues, mainly the harmful gases at both sides of the river, whether there was liquefaction of shallow sand, barrier of the shield machine and freezing construction method for the contact channel and so on. How to properly evaluate and reasonably address these key issues, how to greatly reduce the construction risk and have effective avoidance of waste in construction, through in situ test methods, such as the standard penetration test and test on groundwater flow velocity, the detection of harmful gases, combined with the geology theory, discriminant analysis on the integrated liquefied groundwater parameter values, geological prediction of obstacles and harmful gases and engineering measures, some scientific advices are given, which provide a detailed geological basis to the design and construction.