Safety Problems During Tunnel Excavation in China

In these years, tunnel projects have been raising significantly in quantity and quality with the increasing of city constructions and expressways.Meanwhile, people are paying more attention on safety problems in tunnel constructions. This article has adapted some countries’ tunnel experiences and discusses the main safety problems in tunnel, how to monitor these problems, summarizes the principles and what measurements can be used for different categories problems with some relevant cases. Analyses these information and experience, so that it will have essential impacts on guiding the risks identification and safety management. The article mainly concentrates on these parts: This paper analyzes the typical tunnel construction safety cases with main risk sources, the conditions of risk factors and the mechanism of the tunnel risks to provide basis for assessment. To gain the conclusion of risk grades, the paper combines the geological factors, constructions , other factors , the analysis of the risk factors occurrence and the field survey with the standard query countermeasures.In the end, the paper brings forward the warning system of tunnel construction based on the mechanical tunnel risks. The paper consists of risk identification, risk assessment, risk countermeasures, analyzing each probability of risks.Then, assess the acceptable risk range. Through the special tunnel safety risk assessment, it will identify the key risks , reduce the probabilities in tunnel construction based on the analysis, provide for the construction units risk managements and guides. We can receive the feedback of risk analysis to verify the reliability of the field management. In order to test the tunnel safety, set up the tunnel safety evaluation system, it needs to integrate the collection of plenty of construction site safety management information and the practical tunnel construction dynamic risk analysis model.