固结黏土地层盾构直接破除排水板关键技术研究

宁波地铁5号线1期下穿高速公路路基时存在68°斜交长40 m的含塑料排水板的固结黏土地层，为研究盾构直接通过可行性、刀具选型、施工参数优化等问题，利用TBM掘进模态综合试验平台，进行了不同类型刀具、不同掘进参数的固结黏土地层排水板破除试验。研究表明： 对于含排水板的固结黏土地层，在合理选择刀具、盾构参数并优化掘进参数情况下，盾构法施工直接破除基本可行，试验为宁波地铁工程建设提供了依据，也可为类似工程设计及施工提供参考。

Key Technologies for Shield Cutting Plastic Drainage Plate in Consolidated Clay

The shield used in Phase 1 of Ningbo Metro Line No. 5 has to cross consolidated clay with plastic drainage plates with oblique angle of 68° and length of 40 m when crossing underneath highway roadbed. The highway roadbed would settle and the shield would be jammed in case of improper treatment. In order to prove the feasibility of the shield cutting and direct crossing and study the cutter selection and parameter optimization, some experiments on drainage plate breaking of consolidated clay with different types of cutters and tunneling parameters are carried out based on TBM boring mode experimental platform. The results show that the shield direct cutting plastic drainage plate in consolidated clay is feasible under the conditions of rational cutter selection and optimal parameter settings. The experiments provide basis for the construction of Ningbo Metro has provided experimental reference, and can further provide reference for shield tunneling and design of similar projects in the future.