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在地铁基础坑中监测和预测地下围堆的水平移位
Yue Dong1, Yuanzhong Luan1, Fei Wang1,2
1College of Geodesy and Geomatics, Shandong University of Science and Technology, Qingdao 266590, China.
ACS omega
|July 10, 2023
概括
一个新的调整后勤模型提高了地下围堆稳定性在基础坑的预测准确度. 这种方法提高了城市地下空间工程和铁路运输发展的安全性.
科学领域:
- 地质技术工程 地质技术工程
- 土木工程 土木工程是指土木工程.
- 城市规划 城市规划
背景情况:
- 城市铁路运输和地下空间开发对于缓解交通拥堵至关重要.
- 监测和预测地下围堆的稳定性对于地下太空工程至关重要.
- 青岛基础坑支堆的现有预测模型缺乏足够的准确性.
研究的目的:
- 为解决青岛基础坑支堆的低动态预测准确性和稳定性问题.
- 开发一个更准确的模型来预测地下围堆的变形.
- 提高地下太空工程项目的安全性.
主要方法:
- 提出了调整后勤时间函数模型,结合了三个物理参数来调整变形速度和加速.
- 分析了各种时间函数曲线及其参数含义.
- 使用时间序列数据建立了用于水平移位尖端分析的灾难模型.
主要成果:
- 调整后勤模型表现出优异的性能,RMSE为0.5316,MAE为0.3752,R2为0.9937,表现优于Gompertz,Weibull和Knothe模型.
- 现场验证证实了该模型在各种地质条件下预测堆变形的准确性.
- 确定最大水平位移在0.62-0.71H时稳定,随着挖掘深度的增加.
结论:
- 调整后勤模型提供了更准确的预测地下围堆变形.
- 灾难模型有助于识别稳定性较弱的位置,并为基础坑安全提供多点警告.
- 这些发现有助于确保城市地下工程项目的安全建筑实践.
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