The radioactive waste is disposed safely at the underground and so on, after treatment and storage in the nuclear power facility. During treatment, storage and disposal of radioactive waste, the concrete is used and will be used for various purposes. This paper presents the states of the application of concrete to treatment, storage and disposal of the radioactive waste and the spent fuel from the nuclear power plant. In the chapter of the 1st and the 2nd, it is described what kind, how about and how many the radioactive wastes are. In the chapter from the 3rd to the 5th, it is described the requisites for the concrete material and application of concrete to the management of radioactive waste. Those are the solidification material, the material for the container in the treatment, the radiation shielding wall material in the storage facility and material for the construction of the disposal facility and the water stop structure at the disposal site and so on.

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The Kurobe dam, ccnstructed in 1912, is the first concrete gravity dam for hydroelectric power plant in Japan, located in the Kinu river, a tributary of the Tone river. In 1989, the renewal works of the Kurobe dam were performed, then some characteristics of the dam concrete aged 80 years were widely examined, that is, microscopic observation, compressive strength test, determination of distribution of pore size, estimation of mix proportion, observation with electron probe microanalyzer and so on. The results of the examination are summarized as below. Although the concrete has a slightly low density and rather high permeability, it posesses sufficient compressive strength and distribution of pore size is near to ordinary new concrete, calcium silicate hydration products are stiffly formed, so that there is no indication of deterioration even aged 80 years.

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Corrosion-induced damages have occurred on the reinforced-concrete members (i.e., slabs and beams) being located underneath the superstructures of Fujimi quaywall No. 5 at Shimizu port, which is an open-type wharf with vertical piles and has elapsed 20 and several years after construction. To stop corrosion of reinforcing steel in the salt-contaminated members, the application of cathodic protection (galvanic anode system) commenced in December 1989 and was complete in March 1990. In the system, zinc plates were used as galvanic anodes with the conductive paste. The works were undertaken without any disruptions to cargo operations and without any constructional troubles. The protection criterion of 100 mV potential shift has applied to the system; this potential shift is achieved at current levels in the range of 10 to 20 mA/m² of concrete area. The paper is the first full-scale, nontrial application of cathodic protection to the salt-contaminated concrete structures under marine environments in Japan.

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This report describes the outline of concrete works at the construction of PCCVs in the No.3 and No.4 units at Ohi Nuclear Power Station, Kansai Electric Power Company. In order to obtain the high reliable concrete structures with high quality, various tests for the quality control of the concrete and construction methods were conducted. Precooling of concrete with Liquid-Nitrogen, the forms using special cloth and the newly developed jumping-form were very effective during the works. The good results of the control concerning the structural concrete strengths were obtained by using the curing system following temperature hysteresis of the structural concrete after placement.

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The size of this project is really “Giant” which is large enough to describe as “One of the top leading size project in world-wide”. The project had been developed by the joint co-operative venture among American, Chinese and Japanese. The nature of the building structure is the purely “Cast-in-site Reinforced Concrete”. The project was commenced with its construction in March 1986, and the Structure of Hotel Tower, which is the highest part of project in the height of 167 meters, was topped out in November 1988, and finally the project was completed and was opened for business in Spring of 1990. The building of this project was principally designed by John Portman & Associates (JP&A), Design Consultant in Atlanta, U.S.A. and was further developed by Kajima Corporation who had also managed the Quality Control of the “High-strengthened Concrete for the superhighrised R.C. Structure” as Main Contractor. The structural characteristic of this building can be described as “The first case of the highrised R.C. Rahmen structure with earthquake-resistant and wind-load-resistant structural design in Shanghai”, which are consisted of one tower of 50 storeys and two towers of 32 storeys, and “The mixed design code and specifications” namely, ACI and ASTM for the structural design and the Chinese Code of Practice of construction. The construction method of the tower structure is the normal “1-storey cycle” system, namely, concrete of columns, beams and slabs of one storey were poured at one time by utilizing with the special concrete distributor produced in China for this project. The concrete slump was 18 cm on delivery at sits ground level. The vertical form of the shear walls and the core walls was the jumping steel form with the self-climbing system produced in China. In the results of the actual construction, the concrete having the specifications of 18 cm slump, crushed stone aggregates, water-reducing admixture, could be enough workable even on top of the 50 storey levels. The record of the shortest period of one-storey cycle was 8 days. The quality of the erected structure frame was achieved as the high level more than expected. The followings are the report of the construction results of this project.

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[in Japanese]

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[in Japanese]

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