What percentage of the total project cost is the maintenance cost of the shield machine? The proportion of the maintenance cost of the shield machine to the total project cost varies from project to project, but in general, the annual maintenance cost of the shield machine may account for about 10% to 15% of the total project cost. This proportion includes the costs of regular maintenance, preventive maintenance, fault repair, spare parts replacement, technical support and personnel training.

   However, the actual proportion may be affected by a variety of factors, such as:

   Project scale: TBMs in large projects may require more frequent maintenance and higher spare parts reserves, thereby increasing maintenance costs.

   Construction environment: In harsh underground conditions, the shield machine may suffer more wear and tear, requiring more frequent maintenance and more expensive spare parts.

   Equipment age: Newly purchased shield machines may enjoy free maintenance services from the manufacturer during the warranty period, while old shield machines may require higher maintenance costs.

   Maintenance strategy: An active preventive maintenance strategy can reduce the probability of failures, which may reduce maintenance costs, but this requires additional investment.

   Therefore, the specific maintenance cost ratio needs to be determined according to the specific situation of the project and the operating status of the shield machine. During the project planning stage, it is recommended to work closely with the shield machine supplier and maintenance team to develop a reasonable maintenance budget and plan.