城市大断面浅埋暗挖隧道施工与既有建筑物的响应分析研究

Analysis and Study on Response of Large-section Shallow-buried Tunnel Construction and Existing Buildings in Urban Areas

摘要:

城市地下道路具有断面大、埋深浅、施工环境复杂等特点，常对地表既有建筑物造成不利影响。以济南市玉函路隧道工程为依托，利用现场监测数据分析和数值模拟方法，对城市大断面超浅埋暗挖隧道施工与不同走向的既有建筑物的响应作用进行研究，研究结果如下：既有建筑长边垂直隧道走向时，发生靠近隧道的柱基差异性沉降造成建筑破坏。既有建筑物长边平行于隧道走向，破坏形式为倾斜破坏，平行于隧道走向的建筑柱基不均匀沉降相对最大值发生在隧道掘进过程中，垂直于隧道走向的建筑柱基不均匀沉降相对最大值则有概率发生在全过程中的每个阶段。当地表建筑物存在时，特征点沉降变化趋势与天然地面沉降变化趋势基本一致，但是在建筑物荷载的作用下进行隧道开挖施工，应力释放过程变长，后期的固结沉降量也相应增加，导致地表沉降要明显大于天然地表的沉降。

Abstract:

Urban underground road has the characteristics of large section, shallow burying and complex construction environment, and often causes the adverse effects on the existing buildings on the ground. Relying on the Jinan Yuhan Road Tunnel Project, the field monitoring data and numerical simulation method are used to study the response of large-section ultra-shallow buried tunnel construction and the existing buildings with the different directions. The study result shows that the building damage would be caused by the difference settlement of pile foundation closing to the tunnel if the long edge of the existing building is perpendicular to the tunnel. The failure form is inclined failure if the long edge of the existing buildings runs parallel to the tunnel. The non-uniform settlement relative maximum of the building pile foundation parallel to the tunnel will happen in the tunneling process, and the non-uniform settlement relative maximum of the building pile foundation perpendicular to the tunnel is likely to occur at each stage of the whole process. When the buildings on the ground exist, the variation trend of characteristic point settlement is basically consistent with that of natural ground settlement. During the tunneling construction under the action of building load, the stress releasing process becomes longer, and the later consolidation settlement will also relevantly increase, which results that the land surface settlement is obviously greater than that of natural land surface settlement.