Influence Zone Division and Risk Assessment of Underwater Tunnel Adjacent Constructions

Table 1

Adjacent construction influence zone and risk classification.

No.	Adjacent construction influence zone	Risk level	Accepted guidelines	Disposal guidelines	Control plans
1	Extensively influence zone	Level I	Unacceptable	Risk control measures must be implemented to reduce the risk, at least to a level that is either acceptable or unwilling	Risk warning and emergency response programs, or program amendments or adjustments should be prepared
2	Strong influence zone	Level II	Unwilling to accept	Risk management should be implemented to reduce risk, and the cost of risk reduction should not be higher than the risk after the risk of loss	Risk prevention and monitoring should be implemented and risk management measures should be formulated
3	Fairly Strong influence zone	Level III	Acceptable	Risk management should be implemented and risk management measures can be taken	The daily management and monitoring frequency should be increased
4	Weak influence zone	Level IV	Ignorable	Can implement risk management	Examination can be conducted daily
5	No influence zone	None	No	No need to consider the risk	General management should be checked