大直径盾构下穿越导堤数值分析

以上海沿江通道隧道工程为背景,采用有限差分法模拟超大直径盾构隧道开挖对上海吴淞导堤的影响,评价堤身加固在控制导堤变形、沉降差、堤顶地表沉降等方面的效果;分析开挖面土体加固对控制地层损失的有利影响程度、及在泥水盾构隧道中谨慎采用土体加固的原因。结合现场实际施工情况与监测数据,得出穿越过程中盾构主要施工参数确定的原则及控制措施。

Finite difference analysis of impact of undercrossing super-large-diameter shield tunnel on training jetty

Based on the tunnel project of highway passage along Yangtze River in Shanghai, the impat of undercrossing super-large-diameter shield tunnel on training jetty is analyzed by using the finite difference methods. The deformation of jetty structures, settlement difference and ground settlement of jetty top are used to evaluate the improvement effectiveness of jetty structures. The numerical simulation method in cooperation with the construction experience is employed to study the soil reinforcement at the excavation face of shield tunneling, and its advantages and disadvantages are analyzed. Finally, based on the numerical analysis and in-situ monitoring results, the key construction parameters and control measures of the shield tunnel undercrossing the training jetty are obtained.