Safety Risk Grading Control And Hidden Danger Investigation And Treatment On Subway Shield Construction

In order to realize the scientific management and control of the whole process and all aspects of the construction of the subway shield project,and improve the overall safety level of the system,based on the research background of the whole process operation management of a certain section of the Dalian subway,combined with the actual work of enterprise safety management,the subway shield is constructed The dual prevention mechanism of hierarchical management and control of construction safety risks and the investigation and management of hidden dangers is expected to provide a reference for the safety management of subway shield construction.(1)The HAZOP method was used to identify the safety risk of a certain subway shield tunnel section.According to the classification analysis of accident level,type,time,etc.,three types of accidents with higher risk are obtained.Identify the construction factors,surrounding environmental factors,geological and hydrological factors,three first-level units,and then divide the construction factors into details including "shield preparation and ancillary facilities construction stage,shield launch and arrival stage,shield excavation stage,Segment assembly and simultaneous grouting stage" 4 second-level units,12 third-level nodes;in view of the deviation analysis of each key node in the shield construction process,as well as the possible consequences and causes of the deviation,the summary should be summarized The corresponding control measures have been taken to provide technical support for constructing the safety risk list of subway shield construction.(2)Constructed a subway shield construction factor risk assessment model based on the extension cloud model and the risk matrix method.First,for the complex evaluation index system of the shield construction system,the order relationship analysis method is used to strengthen the consistency of the index,the CRITIC method is used to identify the difference of the index,and the combination weighting realizes the optimization of the weight of the evaluation index.Then,from the two dimensions of accident probability and severity,the improved extension cloud model is used for quantitative assessment,and the risk level is obtained through the risk matrix method;finally,a security risk list containing 44 risk information is constructed(3)Constructed a FRAM model for screening and managing hidden dangers of shield tunneling.First,the construction department is divided into 9 functional modules,and the modules are characterized from six dimensions.Identify the coupling relationship between the modules,search for resonance to determine the easily broken functional links that are systemic hazards,apply control measures to the functional modules,propose systemic hazards management plans,and build a database of 79 hidden hazards at the construction site.(4)Designed an information platform for the hierarchical management and control of subway shield construction risks and the investigation and management of hidden dangers.The platform enters and integrates risk point information,and displays the risk levels in the construction bid section in the form of a risk list.The closed-loop management of hidden hazards is realized through functional modules such as hidden hazard reporting,release,rectification feedback,and acceptance of sales numbers,making safe production work more intuitive.It realizes the supervision and management of the whole process of the subway shield construction by the managers.