基坑开挖对周边建筑物影响的计算及实测分析

Calculation and measurement analysis of impact of foundation pit excavation on surrounding building

预测基坑对周边建筑物的影响是城市地下空间开发中的重要问题之一。结合某地铁车站基坑工程,采用3种方法计算坑外地表、周边建筑的沉降量:一是参考上海地区统计经验,由围护结构侧移估算沉降;二是参考台北地区统计经验,由基坑参数直接计算沉降;三是通过ABAQUS软件建立土体、基坑的三维模型,来模拟施工过程。现场监测结果表明,基坑开挖使周边建筑产生了一些沉降和倾斜;上述3种方法的计算结果对比表明:基于上海地区的统计经验公式和基于台北地区经验的简化预测公式不适于本地区,而采用有限元模拟得到的结果更接近于该工程的实测值。

orecasting the impact of foundation pit on surrounding buildings is an important problem in urban underground space development. Combined with a foundation pit engineering of metro station,three methods were adopted to calculate the settlements of ground surface and surrounding buildings: First,referring to statistical experience of Shanghai region,these settlements were estimated by lateral displacement of the enclosure structure.Second,referring to statistical experience of Taipei region, the settlements were calculated directly by pit parameters. Third,the construction process was simulated by a three-dimensional model of soil mass and foundation pit using ABAQUS. The field measured results showed that some settlements and inclinations of the surrounding building occurred with the pit excavation. Comparisons of the measured results and calculation results of these three methods showed that,the formulas based on the statistical experience of Shanghai region and the simplified formulas based on the experience of Taipei region do not apply in this area,while the simulation results is close to the measured values of this engineering.