厦门越海隧道盾构施工若干技术难题及对策

针对厦门2号线越海段盾构施工过程中出现掘进参数异常、刀具磨损严重及异常失效、堵管等工程难题,通过地质补勘,发现局部存在极硬而多裂隙的破碎带复杂地层。基于此,对越海隧道盾构施工技术进行探讨研究,创造性地提出了海上注浆加固技术,并对刀盘上的滚刀结构进行重新设计。后续施工过程刀盘推力恢复至21 000~22 000 kN之间,掘进速度维持在2~4 mm/min,达到正常掘进水平,同时降低了刀具的异常磨损和消耗。有效解决了盾构海底穿越破碎带复杂地层的难题,使得盾构顺利掘进,可为后续类似盾构越海施工提供指导。

Difficulties and Countermeasures in Shield Construction of Xiamen Sea-crossing Tunnel

Aimed at the engineering problems such as abnormal tunneling parameters,serous tool wear and abormal cutter failure a well a pipe plugging during the construction of the sea-crossing section of Xiamen Line 2,the reasons for the difficulties in shield tunneling in this section were analyzed with the method of geological supplementary exploration,which were caused by the complicated strata in the fractured zone with extremely hard and mulifissures.Based on this,the shield construction tchnology of the sea-crossing tunnel was discussed and studied,a method of stbilizing strata by grouting on the sea was put forward creatively,and the structure of the disc cutter on cutterhead are redesigned.The results show that the method can efctively solve the problem of sea-crossing construction in this kind of strata.The thrust of cutrhead can be restored between 21000 and 22000 kN,the driving speed can be maintained between 2 and 4 mm/min,the abnormal wear and consumption of cutter are also reduced.It will make the shield tunneling smoothly,and provide guidance for similar shield sea-crossing construetion.