砂卵石地层矩形盾构顶掘减摩关键技术研究

Research on Key Antifriction Technology of Rectangular Shield Tunneling in Sandy Gravel Stratum

以成都市四川大学地下停车场下穿人民南路为研究背景,工程采用矩形盾构顶掘法施工,穿越的砂卵石地层具有卵石粒径大、含量高、土层摩阻力大等特点。为了有效地减小顶进过程中的摩阻力,对施工中减摩触变泥浆的成分和性能进行了详细分析,并对浆液与管节,以及周围土体之间的相互作用和注浆对土体移动的影响进行了研究,分析了适用于砂卵石地层矩形盾构顶掘减摩触变泥浆的制作和注浆控制等工艺,探讨了在砂卵石地层中注入减摩触变泥浆需要注意的问题。其成果可为以后类似工程提供技术参考和理论支撑。

Based on the underground parking lot of Sichuan University in Chengdu underpassing South Renmin Road, the rectangular shield tunneling construction is used in the project. The sandy gravel stratum passed through in the project has the characteristics of the big-sized pebble, high content and large frictional resistance of soil layer. In order to effectively reduce the friction resistance in the tunneling process, the composition and performance of antifriction colloidal mud in the construction are analyzed in detail. The interaction among the grout and pipe segment as well as surrounding soil body, and the influence of grouting on the soil movement are studied. The technologies of manufacture and grouting control of antifriction colloidal mud suitable for the rectangular shield tunneling in the sandy gravel stratum are analyzed. The problems for attention during the grouting of antifriction colloidal mud in the sandy gravel stratum are discussed. The results can provide the technical reference and theoretical support for the similar projects.