摘要
对近接既有建筑物的明挖基坑失稳风险评价进行了研究,提出了控制措施。首先基于可靠度原理与瑞典条分法,建立了蒙特卡洛模拟的基坑失稳功能函数,在广泛调研以及对类似工程地勘资料和监测数据统计分析的基础上,总结出了可变参数的分布特征;其次根据概率论原理推导出了基坑失稳风险率的计算模型,以京石客专石家庄隧道近接影响段为工程依托进行了风险分析;最后根据评价结果制定了不同近接程度的风险控制措施。工程实践及监测数据表明,该模型的评价结果客观有效,能切实表征基坑失稳风险的大小,制定的控制措施可显著降低近接房屋对基坑的影响,与风险评价结果相符。其理论、方法、思路和结论可供同类工程所借鉴。
The instability risk of foundation pit close-spaced to existed buildings with open cutting method is studied,and control measures to this problem are also given out.First of all,according to the theory of risk reliability and Sweden slice method,a foundation pit instability function is developed,its parameters＇ distributing characters are concluded based on broad investigation and statistic analysis of similar projects＇ geological survey and local monitoring statistics.Secondly,based on the theory of probability,an instability risk model of foundation pit is developed,and the instability risk for excavation of foundation pit in close-spaced part of Beijing-Shijiazhuang express railway were analyzed.At last,according to final results,risk control strategies are made for object with different closeness level to the building.According to project＇s experiment and monitoring data,it has been proved that using the model could effectively describe the real project,evaluate amount of foundation pit＇s instability risk and the proposed relative risk control strategies could efficiently reduce close-spaced buildings＇ influence to foundation pit,the results correspond to those of the risk evaluation.The analytical approach and the results will be practical and helpful for similar engineering practice.
出处
《地下空间与工程学报》
CSCD
北大核心
2012年第6期1136-1141,1220,共7页
Chinese Journal of Underground Space and Engineering
基金
国家自然科学基金资助项目(No.50878185)
关键词
基坑
失稳风险
可靠度
蒙特卡洛
风险分析
控制措施
foundation pit
instability risk
reliability
Monte Carlo
risk analysis
control measures
