IMPROVEMENT OF COVERCRETE QUALITY BY CRACK CONTROL SYSTEM IN YAMAGUCHI PREFECTURE IN JAPAN

摘要

Yamaguchi prefecture in Japan has established crack control system of massive concrete structures by cooperating works among the local government, private companies, and academic institutions. One of the essential components of the system was to achieve appropriate concrete construction following standard specifications. Due to that achievement, massive concrete crack was well controlled, and furthermore, covercrete quality was much improved, that was confirmed with Surface Water Absorption Test developed by the authors. Another essential component of the system was database of concrete construction fully opened in the website of the prefecture. We analyzed the database with some viewpoints, and several important findings related to good controlling of cracking and durability design of concrete structures. It was clearly exhibited that covercrete quality measured by Surface Water Absorption Test had good correlation with Durability Points calculated by “Recommendations for Durability Design of Concrete Structures -Draft” proposed by JSCE. In the future, we will be able to analyze the effect of each component of construction works on durability of concrete structures, that should be fed back to durability design system.