No abstract

Transportation system utilizing fluid film technology is widely used in various industries. In the U.S. nuclear industry, it is used for transporting concrete casks. Tokyo Electric Power Company (TEPCO) is planning to adopt this design concept to transporting metal cask inside a spent fuel interim storage facility (SFISF). We call this the Metal Cask Transportation System (MCTS). By adopting this system, we can lower the ceiling height of the building, and thus reduce the amount of building materials. The MCTS has not been licensed in Japanese nuclear facility, so that we carried out operational and seismic tests with 1/3-scale model system to verify applicability of this system. As the conclusions, the MCTS has sufficient stability to maintain the safety functions of metal cask. Furthermore, we designed a SFISF introducing the MCTS and confirmed that heat from casks is removed appropriately by natural convection and the dose to the general public is enough low against the statutory dose limit.

Construction of a nuclear power plant (NPP) requires a very long period because of large amount of construction materials and many issues for negotiation among multiple sections. Shortening the construction period advances the date of return on an investment, and can also result in reduced construction cost. Therefore, the study of this subject has a very high priority for utilities. We achieved a construction period of 37 months from the first concrete work to fuel loading (F/L) (51.5 months from the inspection of the foundation (I/F) to the start of commercial operation (C/O)) at the Kashiwazaki-Kariwa NPPs No. 6 and 7 (KK-6/7), which are the first ABWR plants in the world. At TEPCO’s next plant, we think that a construction period of less than 36 months (45 months from I/F to C/O) can be realized based on conventional methods such as early start of equipments installation and blocking of equipment to be brought in advance. Furthermore, we are studying the feasibility of a 21.5-month construction period (30 months from I/F to C/O) with advanced ideas and methods. The important concepts for a 21.5-month construction period are adoption of a new building structure that is the steel plate reinforced concrete (SC) structure and promotion of extensive modularization of equipment and building structure. With introducing these new concepts, we are planning the master schedule (M/S) and finding solutions to conflicts in the schedule of area release from building construction work to equipment installation work (schedule-conflicts). In this report, we present the shortest construction period and an effective method to put it into practice for the conventional general arrangement (GA) of ABWR. In the future, we will continue the study on the improvement of building configuration and arrangements, and make clear of the concept for large composite modules of building structures and equipment.

Since the construction of a nuclear power plant (NPP) requires a very long period, we have to wait for a long time before getting return on the investment. Furthermore, it is unfavorable that the longer construction period makes the construction cost higher. In order to improve these issues, we are studying the way of shortening construction period for the ABWR. In the previous study, we introduced a concept for shortening construction period and master schedule (M/S) based on the large-scale module method. In this study, we have developed the advanced concept for shortening construction period of the ABWR plant based on the rearrangement of its general arrangement (GA) and the application of large-scale composite modules. The estimated construction period is 22.5 months from the 1st concrete work to the fuel loading (F/L).