红砂岩-卵石复合地层刀盘卡停分析及对策

富水红砂岩与大粒径砂卵石复合地层其骨架效应显著,且大粒径漂石随机分布,极易导致盾构施工过程中出现刀盘卡停等故障。本文以兰州2号线公定区间盾构刀盘卡死故障为例,结合工程实际分别从水文地质条件、盾构机性能、刀盘布局等方面分析刀盘卡死原因,并针对性提出渣土改良、盾构机自身减负及消除围岩对刀盘握裹力等技术处理措施,成功解决了红砂岩与大粒径砂卵石复合地层中盾构机卡顿问题,避免了进仓或地面加固后处理工序,实现了工期及成本效益双丰收,对同类型工程具有重要参考价值。

Cause Analysis and Countermeasures of Shield Cutterhead Jamming in Red Sandstone and Sand Gravel Composite Stratum

In the composite stratum of water-rich red sandstone and large-size sand and pebbles,the stratum skeletal effect is significant,and the large-size boulders are randomly distributed,which can easily lead to failures such as cutter head jamming during shield construction.Taking the jamming failure of the cutterhead of the shield machine in the regular section of Lanzhou Rail Transmit Line 2 as an example,the reasons for the cutterhead jamming were analyzed from factors such as hydrogeological conditions,shield machine performance,and cutterhead layout.Measures were put forward accordingly to reduce the burden of the shield machine itself and eliminate the gripping force of the surrounding rock on the cutter head.These measures have successfully solved the problem of shield machine jams in composite formations of red sandstone and large-grained sand and gravel,avoided entering warehouses or post-treatment after ground reinforcement,resulting in construction period and cost-effectiveness,which are of important reference value for similar projects.