【摘要】 地铁车站施工中常穿越大量的市政管道,由于隧道开挖引起地层损失和地表沉降,地下管道将会发生变形,往往影响地铁施工,注浆是对地下管道进行沉降控制的主要技术措施。以北京地铁黄庄站下穿热力管道抬升注浆工程为研究对象,利用三维有限差分数值方法分析了新建车站开挖引起超大管道的变形特征。结果表明,在抬升区注浆单元施加膨胀压力可以较好模拟注浆抬升既有管道的效果;采用应变软化模型,可以有效模拟土体材料的弹塑性力学行为,反映注浆完成后浆脉的固结和周围土体的湿陷作用。对比注浆抬升模拟计算和沉降监测结果,验证了有限差分数值方法模拟劈裂注浆抬升管道过程的正确性和有效性。同时模拟分析注浆抬升管道的影响因素,获得了一些规律性的认识,为劈裂注浆抬升地下管道工程的施工和设计提供指导。更多还原

【Abstract】 Many tunnels need cross the bottom of the existing pipelines during metro station excavation.Surface settlement and ground loss can be found during tunnel excavation;and the deformation of underground pipeline is brought consequently.In general,the key measure to pipeline recovering is grouting,which means grouting in subjacent bed to raising the pipeline.Based on the project of raising an existing pipeline by grouting during the construction of Huangzhuang station of Beijing metro,3-D finite difference method is used to study the feature of pipeline deformation caused by tunnel excavation.In numerical simulation,expanding pressure is applied to the grouting elements to simulate the heaving effect of the pipeline;strain-softening model is suitable for simulating elastoplastic behavior of soil,and embodying the interaction between grouting and soil.The conclusions of numerical analysis agree well with the in-site measured data,which can contribute to the construction and design of raising pipeline by fracture grouting in tunneling.更多还原