地铁盾构施工穿越工程难点分析及相应措施

Difficulties and Preventive Measures in Crossing Projects of Subway Shield Construction

为了有所参照和解决盾构施工工程所面临的一些特殊的工程难题,本文以佛山市三号线南海广场站~叠滘站区间地铁隧道施工为依托工程,研究了盾构机穿越不同类型区间所遇到的工程难点并进行了分析,提出相应措施。该区间地质条件复杂、穿越锚索等地中障碍物、穿越及邻近密集建筑群等地表风险源,且左右线隧道由平行布置转至上下层交叠、小半径曲线等线路条件也增加了该区间施工的难度,会遇到盾构机姿态控制困难、螺旋输送机出土时易发生喷涌、成型隧道衬砌上浮、管片错台、地层扰动大、周边建(构)筑物变形超限等一系列风险与挑战。根据实际情况因地制宜,采取科学合理的方法和工艺,确保了该工程的顺利推进。工程结果表明,佛山地铁三号线南海广场站~叠滘站区间盾构工程施工实践安全可靠。

In this paper,the construction of subway tunnel from Nanhai square station to Diejiao station of Foshan Line 3 was taking as study object to solve some special engineering problems faced by the shield construction method.The engineering difficulties encountered by the shield machine when passing through different section types are studied and analyzed,and corresponding measures are proposed.The geological conditions of this project are complex,passing through ground obstacles(e.g.,anchor cables) and through surface risk sources(e.g.,dense building complex).The geometric layout of the tunnel changed from parallel to overlapping,and the existence of small radius curves condition all increases the difficulty of construction.A series of risks and challenges have encountered during the construction:difficult control of shield machine,easy water gushing when the screw conveyor unloads soil,up floating of tunnel lining,dislocation of segments,large ground disturbance,and excessive deformation of surrounding structures.According to local conditions,scientific methods and technology are adopted to ensure the smooth progress of the project.This engineering practice shows that the shield tunneling construction between Nanhai Square Station and Dijiao Station of Foshan Metro Line 3 is safe and reliable.