地铁隧道近距离穿越既有桥梁桩基影响分析及对策研究

Influence Analysis and Countermeasure Study of Subway Tunnel Crossing Existing Bridge Pile Foundation in Short Distance

摘要:

为了对盾构隧道近距离穿越桥桩基础的影响规律进行精细化研究，以北京地铁19号线支线盾构区间隧道近距离侧穿清河火车站专用Z1匝道桥工程为例，采取数值计算的研究方法，对双线盾构隧道穿越桩基桥梁的全过程进行模拟分析，重点分析施工过程中桥梁基础结构的变形规律，研究结果表明：（1）在盾构施工过程中，位于地铁盾构左右区间之内的桥梁桥桩和承台变形影响较大，建议穿越期间对其相应基础沉降、倾斜值采用实时监测方法进行监测；（2）如果桥梁桩基在施工图设计阶段提前采取了必要的专项设计加固措施，则穿越施工风险会相应降低。

Abstract:

In order to conduct a detailed study on the influence law of shield tunneling through bridge pile foundations in short distance， taking the Z1 ramp bridge project for the tunneling through Qinghe Railway Station in the short distance in the branch shield area of Beijing Metro Line 19 as an example， the research method of numerical calculation is used to simulate and analyze the whole process of double-line shield tunneling through the pile foundation bridges， and the focus is on analyzing the deformation law of the bridge foundation structure during the construction process. The study shows that during the shield construction process， the pile and base slab of the bridge located in the left and right sections of the subway shield have great influence on the deformation. It is recommended to use real-time monitoring methods to monitor the corresponding foundation settlement and inclination values during the tunneling period. And if the necessary special design reinforcement measures are taken for the bridge pile foundation in advance during the construction drawing design stage， the risk of this tunneling construction will be correspondingly reduced.