Risk Assessment Research During The Construction Of Hubin East Road Subway Station Of Xiamen City Based On Entropy Method

With the rapid development of urbanization and the national economy,the city scale is getting bigger and bigger,subway construction is getting more and more necessary,because of the special environment of the subway construction in urban areas with dense population,so the safety of subway construction has always been the focus of attention,so the risk management of subway construction is becoming more and more necessary.If we can find the sources of risk,and according to the comprehensive consideration between the occurrence probability of risk event and event is caused by the consequences of their results,we could put some disposal measures forward for the associated risk,then we can improve the security of subway construction,and effectively reduce the emergence of the subway accident,which is essential for the subway construction.This paper takes Xiamen City subway Hubin East Road station as an engineering example,establish the risk assessment system of the Hubin East Road station during the construction period.And in order to determine the key risk,this paper put forward to the entropy weight method calculation system to weight the risk in the risk assessment system.The main study contents of this paper are as follows:(1)This paper established the construction risk assessment system of the Hubin East Road station,through analytic hierarchy process structure model.Firstly,using the principle of Analytic hierarchy process to divide the risk assessment system of Hubin East Road Station of the subway construction risk project into two tiers of system.the first layer of Engineering risk index are the five subsystem——its own engineering risk,its own subsidiary engineering risk,environmental engineering risk,environmental subsidiary engineering risk,common engineering risk.Then these five subsystems would be further subdivided,which obtained a total of 29 second level risk index.Rating these risk indicators through the specification.To obtain the judgment matrix of the risk indicators under the same system,using the scale method of 1-9,the risk indicators of the same level can be compared to obtain the judgment matrix of the risk indicators under the same system.After checking the consistency of these matrices,calculated the maximum eigenvalue of each judgment matrix.After normalization,the characteristic value group is the weight value which is obtained by using the analytic hierarchy process.(2)The weight of the construction risk events of the Hubin East Road station by entropy weight method doesn’t rely on the subjective judgment of experts which is different from the analytic hierarchy process.The advantage of entropy weight method is that it can be calculated by statistical data,which is more objective.The weight value of the bottom risk index and the weight value of the first level risk index can determine the overall weight value of each risk index in the construction period of the subway station,which can determine the importance degree of each risk index.Comparing the importance degree of each risk index calculated by the analytic hierarchy process and the entropy weight method,We can test the feasibility of applying entropy weight method to the risk assessment of subway station construction.We can see the results according to the comparison: the first risk events ranked in the list of the weight values of each index calculated by the two methods is the Two Hole 2300×1100mm Drainage Box Culvert,which the weight value is 0.1944 by the AHP method,and 0.1241 by the entropy weight method.The top three in the list of the weight values of each index calculate by the two methods are: Two Hole 2300×1100mm Drainage Box Culvert,2300×1100mm Drainage Box Culvert,Jin Xiang Community Office Building.And the row in the forefront of the risk events of the results calculated by the entropy are basically consistent with the information of some of the key risks which is determined by the experts earlier.The conclusion afer comparision is that the entropy weight method for risk assessment is feasible.(3)This paper fanally used the FLAC3 D numerical dynamic simulation software to simulate some of the key construction events of the Hubin East Road station dynamically.The dynamically simulated results can also provide a basis for the later constrction and monitoring measurement,and provides a means to realize the risk information management.