Study On Risk Control System And Monitoring System In Construction Of Beijing Metro

Due to the influence of surrounding building environment, engineering and hydrology geology conditions on metro engineering, there are a large number of safety risks during metro construction. With the rapid development of metro engineering, present safety risk control has been becoming an increasingly serious concern.With the construction experience of Beijing metro as the background, the concept of risk engineering is put forward, and grading standards, pre-warning system, monitoring management mode, safety control and the duties of construction units are introduced on the basis of engineering experience analysis, and then the safety risk control system for metro engineering construction is presented, according to the actual situation and needs of Beijing metro construction. Based on the typical adjacent building environment engineering (including existing metro lines, bridge foundations, buildings and pipelines) in Beijing metro line4,5and the first period of line10, a typical environment risk evaluation and control system for metro engineering is established and applied to the project of Military Museum station in Beijing metro line9. Based on the risk control system and environment risk evaluation and control system, Beijing metro construction safety risk monitoring system is developed. Moreover, above two systems are successfully used in the construction of Beijing metro, from the case of the running tunnel between the Beitaipingqiao station and Beijing west railway station in line9, the effectiveness and practicality of the two systems are verified at the same time.The main contributions are:The core idea of risk control system of Beijing metro construction is put forward, which is the solid basic work, specifying monitoring criterion, standing on preventing and pre-controlling, highlighting process control. Surrounding the core idea, the key works establishing the system are specified, which including strengthening basic works, optimizing control criterion, strengthening control process, combining with qualitative and quantitative analysis, integrating control measures, perfecting expert system, tessellating safety responsibilities.The concept of risk engineering is put forward, and the grading standards is determined. The pre-warning management pattern is proposed, which includes the combination with overall monitoring by construction enterprises and major monitoring by third party monitoring enterprises, integral on-site inspection with construction, supervision and the third party enterprises, and risk pre-warning mainly by the third party monitoring enterprises. The third party monitoring job requirement is proposed, and on-site inspection idea is put forward based on monitoring, and the content and key point of inspection is establish according to the construction method(cut and cover, mining method and shield method) and object(metro engineering itself and building environment risk). The2-level pre-warning system is established, which includes the single monitoring pre-warning, inspection pre-warning and comprehensive pre-warning. The safety risk management pattern and responsibility is proposed, and the risk identification, analysis, classification and control system is formed, which runs through the entire construction course (investigation and environment survey, schematic plan design, preliminary design, construction documents design, construction and after construction accomplishment). The key point of risk control and management in every stage of engineering construction is specified.An evaluation and control system is established for typical adjacent building environment in Beijing metro engineering, including current situation investigation and evaluation, construction effect forecast, the control criterion and measures setting. The specific evaluation process includes dividing adjacent grade, investigation and evaluation, construction effect forecast, determining effect grade, setting the control index and criterion, confirming the control measure, monitoring deformation, evaluation after construction accomplishment.Based on the risk control system of Beijing metro construction, the design idea and process of monitoring system is put forward, and the network frame is proposed. The use case models are designed about monitoring, inspection, risk disposal and engineering document, and the system module includes geology and geography information system, engineering data management, basic information management, engineering affair management and risk pre-warning management. The risk engineering information management is achieved through the studied system under the leadship.The application of the risk control system and monitoring system shows that the system running through the entire construction course meets the needs of large-scale engineering construction of Beijing metro, and the system is a systemic and comprehensive technical management manual for risk management in metro construction. The system can provide insurance service for engineering construction, and can promote the achievement of systematism, normalization and informatization in the risk control work.