Safety Evaluation Of Urban Small-scale Integrated Pipe Gallery During Operation And Maintenance Period

The small-scale integrated pipe gallery adopts a more intensive single-compartment layout,which centralizes municipal pipelines and avoids problems such as "road-style zipper" and "air spider web" in cities.This is beneficial for saving underground space resources,improving urban infrastructure functions,and enhancing urban disaster prevention and mitigation capabilities.However,the single-compartment layout of smallscale integrated pipe gallery is limited,during operation and maintenance,the coupling effect between various pipelines in the pipeline corridor will affect the safe operation of the pipeline.In addition,under the influence of various factors such as equipment,environment,and management,it is easy to create a complex disaster-prone environment inside the pipe gallery,which can cause safety accidents and threaten the operation and maintenance safety of the pipe gallery.Therefore,how to correctly and effectively evaluate the safety of small-scale integrated pipe gallery during the operation and maintenance period is a key issue that needs to be addressed urgently in pipe gallery operation and maintenance processes.This paper evaluated the safety of small-scale integrated pipe gallery during the operation and maintenance period from two perspectives: the safety impact between pipelines and potential safety accidents.For the study of the safety impact between pipelines,an evaluation index system for the safety between pipelines during the operation and maintenance period was established based on factors such as the material of various pipelines,working pressure,and conveying medium.The combination weighting technique based on improvement game theory was applied to integrate the G1 method and entropy weighting method to determine the weights of the indicators.A safety evaluation model for the operation and maintenance period of pipelines based on coupling coordination degree was constructed to judge the operation and maintenance safety status between pipelines.For the study of potential safety accidents,a corresponding accident tree model was established based on the potential risk sources of three types of accidents:fire,water damage,and structural damage.The failure probability of basic events in the accident tree was determined by fusing expert opinions using the trapezoidal fuzzy number.Using the mapping rule between the accident tree and the Bayesian network,a potential safety accident evaluation model for the operation and maintenance period based on the Bayesian network was constructed.With the powerful reasoning and analysis capabilities of the Bayesian network,the probability of accidents occurring can be predicted,and key influencing factors leading to accidents can be identified.Finally,taking a small-scale integrated pipe gallery as an example,the evaluation method proposed in this paper was applied to evaluate its safety during the operation and maintenance period from different perspectives.The results obtained were consistent with the actual operation and maintenance situation of the small-scale integrated pipe gallery,which verified the effectiveness of the evaluation method.The research results of the safety evaluation of small-scale integrated pipe gallery during the operation and maintenance period can provide reference for the operation and maintenance safety management of pipe gallery,and have certain theoretical significance and practical value.