软土地区邻近基坑高架桩基保护的简化模拟

Simplified Simulation of Protection of Viaduct Pier Foundation near Foundation Pit in Soft Soil Area

摘要:

城市中邻近地下工程基坑的建（构）筑物较多，为保证基坑施工时邻近建（构）筑物的正常使用，需限制地下工程基坑支护结构的变形，以减小基坑开挖过程对邻近建（构）筑物的影响；特别是软土地区，基坑支护结构变形较大，除限制基坑支护结构变形外，还需对邻近的重要建（构）筑物采取保护措施。广州南沙地区软土较为深厚，某隧道下穿现状高架桥，桥墩距离基坑较近且桥下净空有限，基坑与桥墩之间土体采用接杆搅拌桩进行加固。采用Soilworks软件对基坑开挖过程中桥墩变形进行简化模拟，模拟结果表明基坑与桥墩之间土体在采用搅拌桩加固后，高架桥墩及桩基变形明显减小。

关键词:软土地区，基坑变形，简化模拟，土体加固，高架桥墩变形

Abstract:

There are many buildings (structures) near the foundation pits of underground engineering in cities. In order to ensure the normal use of adjacent buildings (structures) during the construction of foundation pit, it is necessary to limit the deformation of foundation pit supporting structure in underground engineering to reduce the influence of foundation pit excavation on the adjacent buildings (structures). Especially in soft soil area, the deformation of foundation pit supporting structure is large. In addition to limiting the deformation of the foundation pit supporting structure, it is necessary to take the protective measures for the adjacent important buildings (structures). The soft soil in Nansha area of Guangzhou is relatively deep. A tunnel is under the current viaduct. The bridge pier is close to the foundation pit and the clearance under the viaduct is limited. The soil mass between the foundation pit and pier is reinforced by the mixing pile of connecting rod. And the Soilworks software is applied to simplify and simulate the pier deformation in the excavation of foundation pit. The simulation results show that the deformation of viaduct pier and pile foundation is significantly reduced after the soil mass between foundation pit and bridge pier is reinforced by the mixing piles.

Key words:soft soil area，deformation of foundation pit , simplified simulation, soil strengthening， deformation of viaduct pier