近距离下穿既有运营地铁车站的换乘车站施工风险评价研究

Research on Construction Risk Assessment of Transfer Station Undercrossing Adjacent Existing Operation Subway Station

近距离下穿既有运营地铁车站的换乘车站由于施工环境复杂,存在诸多潜在风险源。一旦施工管控不当,将出现较大质量问题,严重威胁既有地铁站的正常运行和公众安全。为有效评价换乘车站施工风险,引入模糊最优最劣法,构建基于该方法的灰色聚类风险评估模型。利用包含三角模糊数的非线性目标规划求解各指标权重,保留了专家语言中的不确定信息,且有效降低了不一致率。通过构建三角白化权函数,建立灰色聚类评价模型逐层计算一级指标、二级指标风险值,以确定工程风险等级。通过北京地铁16号线苏州街站实例分析,准确识别主要风险指标为变形缝差异沉降和结构裂缝宽度,得到精确风险隶属值8.645,风险等级为Ⅲ。实例计算表明,该方法可有效处理指标模糊性和评价过程灰色性的问题,评价结果合理可靠。

The construction environment of transfer station is complex with many potential risk sources.Improper control may seriously threaten the normal operation of existing metro stations and public safety.In order to effectively evaluate the construction risks of transfer station,a grey clustering risk assessment model based on fuzzy best-worst method is proposed.The nonlinear objective programming with triangular fuzzy numbers is used to solve the weight of each index,which retains the uncertainty information in the expert language and effectively reduces the inconsistency rate.By constructing the triangular whitening weight function,a grey clustering evaluation model is established to calculate the risk values of the first-level and the second-level indexes,so as to determine the engineering risk level.Based on the case study of Suzhou Street Station of Beijing metro line 16,the main risk indicators are the differential settlement of deformation joints and the width of structural cracks.The accurate risk subordinate value is 8.645,and the risk level isⅢ.Case calculation results show that this method can effectively deal with the problems of fuzziness of index and grey of evaluation process,and the evaluation results are reasonable and reliable.