Risk Assessment For Construction Safety Of Hekou Wetland Project Based On Unascertained Measure

In order to better cooperate with social and economic development and make the ecological environment more harmonious,the government has increased its investment in the construction of ecological protection projects in recent years.The construction of wetland projects has greatly improved from the quantity of construction,the scale of construction and the technical level.Hekou wetland project,located in Zunhua,Hebei province,it is an important part of the city key project which is "Luan water source protection project",and its size is the biggest in the country.The project has many types of project that includes frequent process conversion,wide construction range,long construction period,many unforeseeable factors and frequent wading operation,which leads to the high risk of construction safety and difficult to control the hidden danger.It is easy to cause more serious property loss,environmental damage and casualty accident.Therefore,the evaluation of the construction safety risk of Hekou wetland project can provide scientific basis and practical guidance for the management and control of construction safety risk.This article studies from the following aspects:(1)We analyze the characteristics and elements of construction project risk,induce and classify risks,and identify the risk causing disaster process.According to the risk characteristics of wetland engineering construction,we should clarify the principles,methods and procedures of wetland engineering risk identification.Based on personnel factors,technical factors,environmental factors and management factors,the risk categories of construction safety are summarized and analyzed.The Delphi method is used to classify the construction risks of wetland engineering,and the 5types of typical risks such as object strike,mechanical injury,collapse,electric shock,drowning are identified.(2)We investigate the safety risk distribution characteristics of estuarine wetland engineering construction,according to the principles of comprehensiveness,objectivity,relevance,scientificity and operability,and take the 5 types of risk as the first grade index of construction safety risk assessment,and determine the 20 factors such as safety awareness of the workers,safety protection facilities,mechanical scheduling,moisture protection and anticorrosion schemes,and so on as second level index.After that,a comprehensive evaluation index system for construction safety risk of wetland engineering is constructed.(3)We consider the unascertained characteristics such as fuzziness,randomness and nonlinearity of the safety risk index of wetland construction.The unascertained measurement model is used to analyze the unascertained degree of the index quantitatively.By designing questionnaire items and collecting 53 experts’ rating values of effective questionnaires,we conduct an unascertained measurement and evaluation of the construction safety risk of Hekou wetland projects.The information entropy theory is used to empower the lower index and calculate the measure vector of the higher level index.We construct the multi index measure matrix and combine the confidence interval recognition criterion to judge the risk grade of the construction safety.The results show that the safety risk grade of the Hekou wetland project is three grades,and it is in a "moderate" state.It is in the critical point of safety and danger.It is necessary for the safety management department to pay attention to and strengthen the prevention.In this paper,the theory of unascertained measure is used to evaluate the safety risk of estuarine wetland project construction.This method has a strong scientific significance and can be applied to other similar projects.