Multi-objective Optimization To The Maintenance Plan Of Irrigation District Building Group Based On Life Cycle Cost

Irrigation district in China is the basis and security to achieve agriculture modernization and for the development of national economic, but most of the large and medium irrigation districts that are running in our country were built in the fifties and sixties last century, there are serious difficulties of irrigation district further development. The Chinese economy into a high-speed development period, now, large numbers of other industry sectors are beginning to carve up the agricultural water, water resources is necessarily further developed and large numbers of water conservancy projects need to be constructed, water resources development has entered the phase of high cost. In this article, life cycle cost (referred to as LCC) theory will be introduced into the field of maintenance management of irrigation district water conservancy projects, in order to optimize the maintenance plans of projects. In addition, multi-objective optimization model with maintenance methods of the concrete structures and the repair times corresponding to the methods as optimization variables, while minimization of LCC and maximization of service life and deterioration rate as optimization objectives is put forward. A certain optimization method that was chose to optimize the maintenance program of irrigation group structures, look forward to finding a reasonable maintenance program between security and economy. To ensure the maintenance plan of a minimum capital investment for better performance and longer works life that aim at different stages of operation for the project. The pareto solutions of optimization can provide reasonable maintenance plans so as to achieving the purposes of saving costs and maximizing structural performance when the social capital investment is inadequacy.The main content of this article is summarized as follows:(1) Application of LCC theory in the field of water conservancy projects and the practical analysis model research for repairing and strengthening plans.(2) Statistically analyzed the main diseases of the irrigation district concrete structures, and pointed out the main features of the disease irrigation structures; researched the causes and mechanisms of the structure aging and different diseases.(3) Established appraisal index system of hydro-structure's degradation degree regarding structure reliability as appraisal standard, and introduced gray clustering method, fuzzy topology analytic hierarchy process and fuzzy entropy weight analytic hierarchy process as appraisal methods.(4) Taking into account the deterioration process of hydraulic structures has certain randomness, in this paper, the Markov process was using to analyze and predict the deterioration of hydraulic engineering concrete structures, laid the basis for optimization of LCC.(5) Introduced the basic principles of the NSGA-â…¡algorithm, on this basis, a modified group selection of non-dominated sorting genetic algorithm (GNSGA-â…¡) was introduced, this algorithm inherits the original advantages of the NSGA-â…¡algorithm, provides a better optimization method for the multi-objective optimization problems which contains the constraints, so that the final generated non-inferior solutions can be more reasonable.(6) Established the hydraulic structures maintenance plan optimization model based on the LCC analysis, and using the improved group selection of non-dominated sorting genetic algorithm (GNSGA-â…¡) to optimize the maintenance program.