Research On Hazard Source Control Of HL Deep Foundation Pit Support Project In Wuhan

As an effective means of developing and utilizing underground space,the deep foundation pit support plays an important role in underground civil and industrial projects,such as multi-storey basement,underground pipe gallery,underground rail transit and so on.However,due to the influence of supporting design,hydrogeological conditions,stratum complexity and human factors,there are safety risks in the process of construction.If the risk sources are not identified,evaluated and controlled,the accidents will result in casualties and economic loss.Therefore,it is very necessary to identify,evaluate and control dangerous sources in,deep foundation pit support projects.By identifying and evaluating the hazards in deep foundation pit supporting engineering and adopting scientific and reasonable preventive measures,the occurrence of safety accidents can be effectively avoided.Based on Wuhan HL deep foundation pit project,this paper combines theoretical research with field engineering research,qualitative and quantitative research,identities the hazards existing in the construction process of deep foundation pit support project,In consideration of different hazards have different impacts on the toundation pit support structure,personal safety and property losses,so it is divided into foundation pit supporrt structure Failure hazards and non-structural failure hazards.Considering the difterence between the two types of hazards,the former often causes the overall damage,which is influenced by obiective conditions.Therefore,FTA analysis method is used to ca.rry out reverse analvsis from the whole to the part,drawing the logic tree leading to the failure of the whole foundation pit,and finding out the major hazards causing the failure of the foundation pit structure through Boolean operation and simplification;the latter usually causes local damage,The LEC method based on expert experience evaluation is used to analyze the impact of human factors.The evaluation forms are compiled and experts and front-line managers are organized to carry out hazard assessment to identify major hazards of non-structural failure.Through the comprehensive use of the two methods,the identification and evaluation of the hazard sources with different attributes in deep foundation pit projects are carried out,and finally five major hazards and eight major hazards leading to structural and non-structural failure of foundation pit are identified.Different measures should be taken according to different hazard sources to avoid the occurrence of safety accidents,in order to control the major hazard sources of the whole foundation pit project.