Disaster Control Technology And Risk Management Of Urban Tunnel Construction With Complex Geological Conditions

Because of the rapid development of national economy and high concentration of urban population, worldwide construction of various of urban tunnel tend to increase dramatically in order to relieve or radically solve the pressure on urban environment caused by population increase. However, problems of security and environment pollution during urban tunnel construction are also increasingly urgent. To some extent, the consideration of structure design and construction method of urban tunnel distinguishes from that of soft soil tunnel, due to its special position. Meanwhile, it is remained to be done for the problem of the influence of blasting vibration under complex geological conditions to the constructions around, comprehensive management of water inrush, and the government of the whole process of construction.By referring to the results of judgment risk level of excavation process and surrounding buildings, this paper mainly concerns of urban tunnel blasting vibration and tunnel water inrush disaster risk control, taking advantage of technique advance. By referring main safety technique risk as study object, works were accomplished for risk judgment, access and process control of tunnel construction security under normal construction conditions of urban tunnel. The main achievement and study progress are as follows:(1) Main risk factors encountered during the construction of urban tunnel under complex geological conditions were studied. Risk level identification methods were proposed. Indicator system and risk level were established. The corresponding risk accept guideline were also proposed.(2) Risk estimation and control technology of urban tunnel water disaster risk estimation were studied. On the basis of Zhongliangshan tunnel project of track traffic in Chongqing, dynamic water information grouting system and non-grout prevent wall deep hole grouting control key technology were established. Combining varies sorts of management access methods, effects of grouting pre-curtain grouting were estimated.(3) With reference to urban tunnel construction main methods, consideration of existing risk factors in blasting consideration and combination of existing risk estimation methods, large diameter spiral cutting blasting technology and shallow buried tunnel cushion blasting technology were proposed. (4) Summing up above achievements, this paper established a tunnel construction security protection system under complex geological conditions, with an optimized design construction, a basement of engineering disaster protection method, a platform of security management system and in-situ detection statistics management system, and a judgment of in-situ detection information feedback. Results of this paper provide a technical direction for urban tunnel construction security protection under complex geological conditions.