Concrete works in the construction of PCCVs in unit No.3 and No.4 at Ohi Nuclear Power Station

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. (author)