基于梯形模糊数和C-OWA算子的地铁盾构施工风险评估方法

城市地铁盾构隧道施工过程十分复杂,涉及诸多潜在风险,施工控制不当将严重威胁公共安全。为有效管控地铁盾构隧道施工风险,提出了一种基于梯形模糊数和C-OWA算子赋权法的风险评估方法,将专家评价信息用梯形模糊数表示,运用模糊数运算规则计算各潜在风险因素的风险水平,运用C-OWA算子赋权法计算所得各风险指标权重,从评价体系底层因素向上逐层运算,确定各级风险指标的风险水平,依据风险矩阵进行风险等级划分。以深圳地铁12号线某盾构隧道区间为例,应用所提出的方法对风险进行评估,获取了需实施风险防范措施的潜在风险因素。实例计算表明,该方法合理可靠,处理定义模糊和涉及主观性的复杂问题相对于传统风险评估手段更具优势。

A Risk Assessment Method for Metro Shield Construction Based on Trapezoidal Fuzzy Number and C-OWA Operator

The process of shield tunnel construction for metro is very complicated involving many potential risks. If not properly controlled, the construction will pose severe threats to public safety. In an attempt to effectively control the risks of shield tunnel construction, a risk assessment method based on trapezoidal fuzzy number and C-OWA operator is proposed. The evaluation information of experts is represented by trapezoidal fuzzy numbers, and the operational rule of fuzzy number is adopted to calculate the risk level of each potential risk factor. The risk level of evaluation indicators at all hierarchies, combined with the weight of each risk index calculated by C-OWA operator weighting method, is determined by calculating down-top of the evaluation system. The risk rating is obtained according to the risk matrix. The proposed method was applied to evaluate the construction risks of a shield tunnel construction of Shenzhen Metro Line 12, and the potential risk factors that require risk prevention measures in the project are obtained. The example shows that the proposed method is reasonable and reliable. Compared with traditional risk assessment methods, it has more advantages in dealing with complex problems involving fuzzy definition and subjectiveness.