以南京江岛变电站电源进线工程为例,介绍渗透系数为10-3 m/s的砂性地层中土压盾构掘进和快速穿越夹江技术,扰动地层中盾构始发和接收加固方式以及涌砂冒水的应急处理技术,分析盾构推进对防洪大堤的影响.研究结果表明:盾构试掘进提出的盾构推力,刀盘扭矩及转速,土仓压力等掘进参数合理可行,实现了快速推进施工;使用组合式轨枕能大大提高工作效率并适应狭小盾构空间内作业;采用三轴搅拌桩+垂直冻结法加固端头,盾构水中接收技术确保了盾构安全到达.%By taking Nanjing Jiangdao substation cable construction as an example, this paper introduced the technology of EPB shield thus tunneling and piercing through Jiajiang in sandy strata whose permeability coefficient is 10-3m/s, the type of shield originating and arriving strengthening manners in disturbed soil and the technology of emergency treatment with sand gushing and water leaking. The influence of shield tunneling on the flood control embankment was analyzed. The results show that the boring parameters such as shield thrust, cutter head torque and speed, pressure of the soil chamber in this putting forward trial driving are reasonable and feasible, and this realizes the fast feed construction. The utilization of combined sleeper can improve the work efficiency greatly and it can also adapt to the narrowness shield space. By using three-shaft stirring pile+vertical freezing to improve strata, the technology of shield water receiving can make sure the safety of shield arriving.
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