南宁地铁2号线盾构选型设计与适应性分析

盾构的选型与设计对地铁区间盾构施工具有重要意义,其选型的合适与否直接影响到盾构施工的成败。针对南宁地铁2号线所遇到的黏土层、硬岩层、夹杂碎石砂砾层、上软下硬地层及岩溶地层等多种地层相结合的特殊复杂地质条件,提出盾构选型总体要求,开展对盾构动力设备、刀盘、刀具等关键部位的选型研究,同时优化防泥饼、螺旋输送机、小倾角皮带机和同步注浆设计方案以及地质加固方案。通过实际掘进参数和地表沉降数据分析,结果表明盾构设备选型及优化设计方案对南宁地区特殊复杂地质条件适应性良好。

Type Selection Design and Adaptability Analysis of Shield Used in Line No. 2 of Nanning Metro

The type selection design of shield is very important to shield construction of metro; it directly affects the success of the construction. The Line No. 2 of Nanning metro crosses complex geological conditions, i. e. clay, hard rock, gravel, upper soft and lower hard stratum and karst stratum. As a result, the general requirements for shield type selection are put forward in terms of power device, cutterhead and cutter; meanwhile, the design of mud cake prevention, screw conveyor, small angle belt conveyor and synchronous grouting system and geological reinforcement methods are optimized. Finally, the actual tunneling parameters and ground surface settlement data show that the adaptability of the shield machine in Nanning area is good.