Study On Unsafe Actions Of Urban Underground Space Collapse Accident

With the rapid economic and social development,urban land resources are becoming scarcer,and China has entered the stage of large-scale development and utilization of urban underground space.At the same time,urban underground space collapse accidents have become more frequent,so the prevention of urban underground space collapse accidents becomes indispensable.This article takes 70 cases of urban underground space collapse accidents with detailed investigation reports as the research object,and comprehensively and systematically analyzes all unsafe actions leading to the accidents with the help of behavioral safety “2-4” model theory as the analysis tool,and establishes all Safe action library;by classifying the unsafe actions within different organizations of underground space engineering,determine the unsafe actions of key position responsible personnel,statistically analyze the frequency of unsafe actions,reveal the occurrence of urban underground space collapse accidents,and then propose effective Precautions.The main research conclusions are as follows:1.The occurrence law of urban underground space collapse accident was studied.From 2011 to 2018,urban underground space collapse accidents across the country showed a trend of decreasing first and then rising;from the perspective of accident types,urban underground space collapse accidents were mainly underground pipeline construction collapse accidents,subway construction collapse accidents and tunnel construction collapse accidents These three types account for 92% of the total accidents.Among them,the number of underground pipeline construction accidents occurred first,accounting for 50% of the total accidents.2.A comprehensive and systematic analysis of the unsafe actions of urban underground space collapse accidents,and the establishment of a database of all unsafe actions of urban underground space collapse accidents.According to the "2-4" model theory of behavioral safety,a total of 403 unsafe actions in 70 accidents were analyzed,of which 303 unsafe actions(VA),46 unsafe actions(VO),and VC)Appeared 11 times.3.The unsafe actions issued by different organizations in urban underground space accidents are studied.A total of 303 unsafe actions occurred in construction units,divided into 11 categories.Among them,the unsafe actions that occurred more than 20 times include "safety production education and training work is not in place","protection work is not in place during excavation",etc..A total of 79 unsafe movements occurred in the construction supervision unit,which were divided into 4categories.Among them,the most frequent occurrence was “the on-site violations were not effectively supervised”.A total of 26 unsafe actions by the construction unit were divided into 3 categories,of which "illegal subcontracting","project engineering irregular handling" and "project engineering related irregularities" occurred 8 times,15 times and 3 times respectively.4.The unsafe persons in the construction accidents of urban underground space are studied.The results show that the persons responsible for unsafe actions mainly include senior managers,middle managers,on-site managers and on-site operators.Among them,the person responsible for the unsafe actions of the construction unit issued the most unsafe actions by the safety officer and the team leader,which occurred 183 and 162 times respectively,accounting for 21.86% and 19.35%.The person who is responsible for the unsafe actions of the supervision unit is the director with the most frequent unsafe actions,which occurs 120 times,accounting for 50.63%.The person in charge of the unsafe action of the construction unit is the person in charge of the project with the most unsafe actions,with 26 occurrences,accounting for 89.66%.In terms of personnel level,the middle-level management personnel of the construction unit issued the most unsafe actions,accounting for 29.35%.The top management personnel of the supervision unit issued the most unsafe actions,with 75 occurrences,accounting for 38.24%.The highest number of unsafe actions issued by the construction unit was the senior management personnel,which occurred 26 times,accounting for 89.66%.5.In order to reduce the occurrence of urban underground space collapse accidents,the preventive countermeasures of unsafe actions are analyzed from the perspectives of the three responsible entities of the urban underground space project:construction unit,supervision unit and construction unit.