Simplified method for evaluating excavation-induced impact on surrounding environment based on numerical analysis
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摘要: 上海市《基坑工程技术规范》根据上海地区大量工程实测数据给出了预估深基坑开挖对周边建筑物影响的简化分析方法,但是该方法不能综合考虑影响基坑变形的主要因素。本文通过对有限元计算结果的分析及拟合,推导了能综合考虑基坑系统刚度、挖深和宽度因素的板式支护体系基坑地表最大沉降的简化计算公式,并给出了地表沉降预测曲线。采用给出的简化方法预测了若干板式支护体系基坑墙后地表沉降并与实测结果进行了对比,验证了方法的适用性。最后采用地表沉降预测曲线作为预估上海地区板式支护体系基坑开挖对环境影响的简化方法,计算实例表明该简化方法能较好地预估上海地区基坑开挖对周边环境的影响。
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关键词:
- 板式支护体系基坑 /
- 环境影响 /
- 简化方法 /
- HS-Small模型 /
- 有限元法
Abstract: A simplified analysis method is proposed by Shanghai Technical Code for Excavation Engineering to evaluate excavation-induced damage of buildings. However, this method can not consider the main factors which affect the deformation of excavations. The simplified calculation formula considering system stiffness, excavation depth, excavation width for the maximum ground surface settlement is deduced by normalizing FEM results. The ground surface settlement profile behind the embedded walls is also provided. The validity of the simplified method of ground surface settlement prediction for excavations retained by embedded walls is verified by calculating several case histories in Shanghai. The ground surface settlement profile is used as the simplified analysis method to evaluate excavation-induced impact on surrounding environment. An example shows that this simplified method is suitable for analyzing excavation-induced impact on surrounding environment. -
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