Study On Safety Evaluation Of Blasting Demolition Of A High Chimney In An Industrial Plant

With the rapid development of Chinese urbanization level,a large number of structures constructed in urban central zone need to be moved or dismantled because they cannot meet the new use requirements or meet the needs of the city.How to dismantle the old structures safely,quickly,efficiently and economically is a problem that has been studied in the industry.Especially in the complex urban environment,the safety of blasting demolition construction is always the focus of attention when the chimneys,water towers,large cooling towers and other tall structures are demolished by blasting.When blasting demolition is carried out in urban areas,there are many dangerous sources,which will also bring various safety risks.In this paper,through the study of high chimney blasting demolition project in an industrial plant,in order to make the identification of hazard sources more scientific and accurate,on the basis of referring to a large number of relevant literature,collected and analyzed the safety accidents occurred in the blasting demolition construction cases in the past,identify the risk factors.Such as blasting design error,blasting construction scheme is unreasonable,the structure of the building is not analyzed clearly,resulting in insufficient explosive force.The pre-risk analysis method was used to summarize the risk factors identified in the combined copy study method and case analysis method.Meanwhile,the risk factors of the project were identified in combination with the actual situation of the project,and the risk factors were evaluated.Finally,7 risk units with greater impact on the construction safety of the project were selected,with a total of 20 risk factors.In the research process,the analytic hierarchy process is used to compare the identified influencing factors in pairs,calculate the comprehensive weight of all indicators,and conduct importance analysis and ranking.According to the evaluation indexes obtained by the analytic hierarchy process,the fuzzy comprehensive evaluation method constructs the fuzzy comprehensive evaluation set,determines the evaluation grade and each scoring interval,determines the membership degree of the evaluation indexes by scoring all factors,selects the appropriate membership function and fuzzy operator,constructs the fuzzy comprehensive evaluation model,determines the weight vector of the evaluation factors,and carries out the fuzzy comprehensive evaluation.Fuzzy comprehensive evaluation set and total fuzzy comprehensive evaluation set of each index are obtained,and the overall grade of the project is between general safety and relatively safe by calculation.According to the evaluation results,starting from the dangerous factors that have great influence,the corresponding countermeasures are put forward for the project from the initiation stage to the final process of slag removal,so as to improve the safety in the blasting demolition process.In this paper,safety system engineering analysis method is applied to a practical case through the safety evaluation study of blasting demolition of high chimneys in an industrial plant,which can help us better prevent the occurrence of accidents,reduce casualties,avoid property losses in the process of the project,and make the whole system safer and more scientific.