宁波软土地区地铁深基坑施工风险评估与管控研究

Study on Construction Risk Evaluation and Control of Metro Deep Foundation Pit in Ningbo Soft Soil Area

通过对国内典型软土基坑事故案例的调查分析,得出结论:围护结构变形破坏是导致基坑事故发生的主要因素。在此基础上,依托宁波轨道交通4号线翠柏里站深基坑工程,对宁波典型软土地区地铁深基坑施工风险评估与管控进行研究。首先,基于WBS-RBS风险辨识方法,分析了软土基坑的风险源及其危害;其次,针对基坑开挖的随机性和模糊性特点,采用模糊综合评价方法,进行施工阶段风险评估;最后,对施工阶段风险评估结果进行分析,并提出了相应的风险管控措施。所取得的研究成果可为宁波软土地区基坑施工风险评估和管控提供借鉴经验。

With the investigation and analysis on the construction accident cases of the domestic typical soft soil foundation pits,the conclusion showed that the deformation failure of the enclosure structure would be main factor to cause the foundation pit accident occurred.Based on the circumstances,depended on the deep foundation pit at Cuibaili Station in No.4 Line of Ningbo Rail Transportation,a study was conducted on the construction risk and control of the deep foundation pit in Ningbo typical soft soil area.First,based on the WBSRBS risk distinguishing method,the risk sources and the danger of the soft soil foundation pit were analyzed.Second,according to the random and fuzzy features of the foundation pit excavation,the fuzzy comprehensive evaluation method was applied to the risk evaluation of the construction period.Finally,an analysis was conducted on the risk evaluation results of the construction period and the relevant risk control measures were provided.The study results obtained could provide the reference experiences to the construction risk evaluation and control of the foundation pit in Ningbo soft soil area.