Risk Assessment And Prediction Study Of Deep Pit Foundation That Adjacent To Existing Subway

With the continuous development of China's urbanization process,urban infrastructure construction is also in full swing in progress.Urban rail transit,large-scale urban complex,large commercial buildings are constantly erected,underground space used for the construction and utilization increased continually and at the same time foundation pit construction safety risk issues have attracted more and more attention.And as the city continues to join the subway track of the traffic era and the pit project is close to the urban area,resulting in more and more complex surroundings of the foundation pit project,especially the closer distance of infrastructure projects and urban rail transit,and even the intersection of the foundation pit project with the subway tunnel.This situation is much more frequent in recent years.Because deep foundation pit project may cause too large deformation of adjacent existing subway tunnel,thus jeopardizing the safe operation of existing subway.Therefore the construction risk of the deep foundation pit project near the subway has become the focus of attention in the academic and engineering circles.In this paper,the safety risk assessment of the deep foundation pit near the existing subway is taken as the research content.Through the risk analysis,the index system is established and the evaluation method is selected.Finally,taking the deep foundation pit project of the existing subway in the city of Zhongyuan as an example,this paper assess the impact of the safety risks in the construction process and their impact on the project.In this paper,through the research on the development of deep foundation pit at home and abroad,as well as in the development of deep foundation pit project,the experts have studied the safety risk from different angles and different methods,and have an in-depth study of the deep foundation pit project,By comparing and analyzing the applicable scope and advantages and disadvantages of different evaluation methods,the appropriate methods are used to study the specific situation of engineering examples.This paper analyzes the safety risk of the deep foundation pit project of the existing subway,analyzes the construction safety and evaluation index system of the deep foundation pit near the existing subway,and explains every index.Based on the established safety risk assessment index system,the material and resource extension method based on entropy weight method is used to evaluate the potential safety risks of human,material and machine in the construction of deep foundation pit near existing subway.The results obtained Indicating that the project in the construction process of management norms,reasonable,by the management of the safety risks caused by the occurrence of less likely.At the same time,the BP neural network prediction model is established on the basis of the theoretical knowledge of BP neural network.The model is trained,learned,predicted and utilized based on the monitoring data of the subway and the relevant data of the pit construction monitoring.Construction of the accuracy of the forecast results to check the results of the forecast and the actual situation of the error of 0.7% below the prediction of a higher degree of accuracy.With the accumulation of subsequent data,BP neural network model using a dynamic method of continuous learning,predict the accuracy will continue to improve.According to the prediction of the safety risk assessment and the development of the subway edge in the construction of the deep foundation pit near the existing subway,the safety risk control can be formulated in the subsequent safety risk management of the deep foundation pit construction Measures and programs that can be done in advance.