宁波地区深基坑工程施工预警指标及风险评估研究

Forewarning Index for Deep Foundation Pit Construction and Risk Assessment in Ningbo area

在国内外现有关于基坑变形、控制技术和标准、实验和经验数据的文献资料和科研成果基础上,结合宁波轨道交通建设工程实践,并基于14个深基坑工程实测数据,对宁波地区软土深基坑的变形特性进行研究,建立了宁波地区深基坑监测过程中的预警指标体系,确保了基坑安全。进而,利用风险分析理论对深基坑工程开挖期的主要风险事故发生的概率和后果进行分级,并采用基于权重的专家调查法进行调研,最后通过计算得到了宁波轨道某车站深基坑工程施工风险度,并判定了风险级别。

Combined with Ningbo urban rail transit project construction, the deformation law for deep foundation pit engineering is investigated, and the characteristic of horizontal displacement and settlement of ground is obtained based on the monitoring data of 14 deep excavations. On basis of the literature data and research achievement on deformation characteristic, controlling technology and norms, as well as experimental and empirical data, the forewarning index for foundation pits monitoring in Ningbo soft clay region is presented. Furthermore, the theory and method＂ of risk analysis is used to grade the probability of occurrence and the consequence of the risk accident during the excavation. The weight-based expert surveying is used in investigation, and the risk level in the construction of a deep excavation in Ningbo urban rail transit project is obtained and the risk class is determined.