Research On Life-Cycle Design Index System For Port Concrete Structures

Port concrete structures are usually under the combination effect of loading and aggressive environment, resulting in premature failure of structural members, even creating serious security problems due to the inadequate durability. Therefore, it is urgent to predict the life-cycle performance of port engineering from the design stage, and to establish the life-cycle design index system of port engineering accordingly. On the one hand, limited resources of the port will be used efficiently. On the other hand, it can avoid the possible loss of security and economy caused by the premature failure of port structures. This paper carries out the systematic research on the life-cycle design index of port concrete structures from two aspects, including green evaluation and performance evaluation. Green index evaluation system of port engineering and performance evaluation system integrated time index, performance index and economic index of port engineering, are built up, on the basis of which the life-cycle design evaluate software system of port engineering is developed. The conclusions are as follows:(1) The results durability survey of port concrete structures are analyzed. And then, the duralility-sensitive members of port structures are classified. The service life assessment model of reinforce concrete structures in chloride corrosion environment is established and the maintenance strategy is considered, so the life-cycle service life assessment of sensitive members can be achieved. It is verified by a case study that the model can be used for predicting the service life of the sensitive members of port concrete structures.(2) The research of port concrete structures performance index and economic index is carried out, which is based on the research of the service life of port engineering concrete structures. The relationship between reliability index of port concrete structures and time is establishment. The life-cycle cost model of port concrete structures is also proposed. Several design plans are compared and the result show that the proposed calculation model can be use to determine the cost-optimal design plan.(3) The research status of green evaluation is summarized, and the importance of the evaluation of port engineering green degree is explained. The green index system, which combines the factors associated with sustainable development and environmental protection with the consumer satisfaction, is built up. The analytic hierarchy process (AHP) applied the three-scale method and the trapezoidal fuzzy number is used to analysis the green indicator system. A numerical example shows that the green indicator system and its fuzzy analytic hierarchy process method can be used in the evaluation of the port engineering green indicator. (4) The evaluation system of life-cycle design index of port engineering is developed. The evaluation system can be used to analyze and evaluate time index, performance indicator, economy index, and green index of port reinforced concrete structural components under different environmental conditions and different parts, which provide technical support for the life-cycle design of port engineering.