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Based on the references , the mechanical models are created to study the pre support mechanism of forepoling bolt structure.

在文献［１］、［２］、［３］基础上建立了超前锚杆预支护机理的力学模型。

The urban underground pipe-jacking method attempted oversea is adopted as the tunnel pre-support technique.

采用国际上已尝试的城市地下管道顶管作为隧道预支护技术,对顶管施工技术进行归纳总结,分析顶管作为隧道预支护的原理;研究了地面建筑物、地下管线及地下铁道允许的隧道施工引起的地表沉降基准;说明了大刚度顶管作为隧道预支护与传统预支护相比,可大幅度减少隧道施工引起的地表沉降。

In order to control the subsidence of the interval tunnel and guarantee the safety of operation strictly,pipe-jacking is used as pre-support for the first time.

为了严格控制既有环线区间隧道的沉降,确保环线地铁运营安全,首次采用了顶管作超前预支护。

Strictly to control the subsidence of the interval tunnel and ensure the safety of the operation, pipejacking is to be used as pre-support for the first time.

为了严格控制既有环线区间隧道的沉降,确保环线地铁运营安全,准备首次采用顶管作超前预支护,用3D-Sigma三维有限元软件进行施工效应的计算模拟,掌握顶管预支护洞室的力学效应。

Based on Weining station #3 passageway of #2 line west extending engineering in Shanghai subwayt,he synthetic construction techniques of pipe pre-support,deep hole grouting in working face,short excavation and strong support are used in silty stratum.

分析结果表明,施工过程中洞室结构稳定,浅埋暗挖管幕预支护施工方法可行,并可实现洞内施工安全和施工地面沉降的控制要求,解决了明挖施工对城市交通的干扰,所得结果可为后续类似工程提供一定的理论参考。