Application of unascertained measure theory in safety risk assessment of shield tunneling
The construction of shield tunneling under existing tunnels usually involves large risks.To accurately and effectively evaluate the risk level,this paper proposes a safety risk assessment model for shield tunneling through existing tunnels based on the unascertained measure theory.Firstly,this paper established the safety risk assessment index system of shield tunneling.The establishment of the index system is based on the research of relevant specifications and existing documents and combined with the characteristics of shield tunneling under existing tunnels.The index system includes five first-level indicators of shield tunneling parameters,new tunnel conditions,existing tunnel conditions,geological conditions and construction management conditions,as well as nineteen second-level indicators such as tunneling speed,tunneling thrust,and grouting pressure.Secondly,the comprehensive safety risk is divided into five levels,and the classification criteria for each indicator are clarified.Then,based on the entropy weight unascertained measure theory,a safety risk assessment model for shield tunneling through existing tunnels is constructed.The entropy weight method is used to determine the indicator weight.According to the unascertained measurement theory,it constructs the single indicator unascertained measure function for each indicator.The data values of each indicator were substituted into the single indicator unascertained measure function to obtain a single indicator measure evaluation matrix.Combining the index weight and the single indicator measure evaluation matrix,the multi-indicator measure evaluation vector is calculated,and the safety risk level is determined according to the confidence criterion.Finally,applied the proposed model to an actual shield tunneling project to evaluate its safety risk level.The results show that the evaluation results of the model are consistent with the actual risk level.And verified the effectiveness of this model by comparing it with the fuzzy analytic hierarchy process.The research results can provide decision-making support for actual construction safety management.
safety engineeringshield tunnelundercrossing constructionrisk assessmententropy weight methodunascertained measure theory
万方数据
维普
