基于模糊层次分析法的黄河岸滩深大风井安全度评价

Safety Evaluation of Large and Deep Shaft on Yellow River Floodplain Based on Fuzzy Analytic Hierarchy Process

兰州地铁1号线奥体中心站一世纪大道站区间隧道下穿黄河,在黄河岸滩设中央风井。针对风井建造过程中的灾害事故特点,将风险可能性、损失等级标量化评分并提出与规范风险接受准则中4级风险相对应的隶属度;采用专家调查法进行风险因素辨识,构建包括地连墙、施工降水、土方开挖等两层风险指标层次模型;采用模糊层次分析法确定风险模型各因素权重并得到岸滩风井在内墙顺作、内墙逆作(无止水帷幕)、内墙逆作(有止水帷幕)3种工况下的风险可能性值和风险后果值,实现对规范的量化补充和设计过程风险控制及评价。结果显示,土体滑坡是影响风井安全的首要因素,内衬逆作+止水帷幕工法为最佳设计方案。

The tunnel located in the section between Olympic Sports Center Station and Century Avenue Station of Lanzhou Rail Transmit Line 1 passes through the Yellow River,and a central air shaft is set on the Yellow River floodplain.Being directed against the disasters features in the construction of shaft,this paper firstly quantified the risk possibility and lost grade and put forward the membership degree corresponding to the 4-Ievel risk based on code for risk management of underground works in urban rail transit.Secondly,the expert investigation method was adopted to identify the risk factors,and risk hierarchy model was constructed,consisting of 2-layer grade indexes including retaining wall,construction precipitation and earth excavation.Lastly,fuzzy analytic hierarchy was used to determine the weight of each factor,risk probability and risk consequence value in the model result of 3 construction methods,namely top-down.bottom-up with or without waterproof curtain method.It could serve as the code supplement and complete the risk assessment and control.Analysis results show soil landslide is the main influencing factors and bottom-up with waterproof curtain is the optimal scheme.