The Deformation Analysis And Optimization Of CA20 Module Single Wall Construction Of AP1000 Nuclear Power Plant Based On The Analytic Hierarchy Process(AHP)

Nuclear power plant is an important application of nuclear energy. It is not only the cornerstone of the state’s economy development, but also the outlook of state’s industry level. As the low carbon emission increasingly attract world attention, nuclear power plant is leading the new energy development of its zero emission and high power output per single unit. Passive safety and module construction are the unique symbol of AP1000 as the 3rd generation nuclear power plant. In the background of clean power development, the first unit of AP1000 in the world is built in Zhejiang Sanmen 1# and becomes the support project on the importing of AP 1000 technology.Because of the unique module construction and safety design, there is no experience to refer to during the construction of first AP1000 unit. The course of building is not only the exploration from drawings to the reality, but also to accumulate the experience for the consequence plants. Therefore, it is important to gather the construction information and analyze the problems. In the course of building Sanmen 1# unit, different kinds of problems come up, in which CA20 module single wall deformation is typical one as it is in the critical path.This paper focuses on the process of construction of CA20 module single wall. An comprehensive analysis on exceeded tolerance of deformation of CA20 module single wall in different construction stages is carried on based on a large number data records of the construction document. The main effect factors include: sub-module fabrication and transportation, fit-up and weld, assembly rotation, CA20 module set, and concrete pour. This paper adopts different methods, i.e. the statistical analysis, theoretical computation, finite element analysis, etc to study different deformation during welding and concrete sections. The deformation trend of the single wall in a series construction phase and the corresponding influencing factors are summarized though those data analysis.According to the multiple and complicated factors involved in the construction, AHP is applied to represent such complex problem as a hierarchical structure and effectively solves the decision problem with multi-variable and multi-criteria. The important sequence of the factors is studied by AHP and the conclusion is drawn in that: the ranking order follows concrete section, weld section, lift section, assembly turnover section, etc. Such analysis results provide the basis and the experience of modular construction for the follow-up of nuclear power plant, and are conducive to the quality control management on subsequent similar construction.On the base of AHP result of, optimization solutions are proposed to effectively solve the complicated coupling construction issues. The AHP analysis on activities of AP1000 construction process provides valuable experience for the subsequent modular construction project.