STATUS OF RESEARCH AND APPLICATIONS OF CONCRETE-POLYMER COMPOSITES IN JAPAN
The present paper reviews the status of research and applications of concrete-polymer composites such as polymer-modified concrete (mortar), polymer concrete (mortar) and polymer-impregnated concrete (mortar) in the Japanese construction industry. In Japan, the concrete-polymer composites as environment-conscious construction materials have been developed with a great interest in recent years. Currently they are prevalently used as dominant construction materials in various applications because of their high performance, multifunctionality and sustainability compared to conventional cement mortar and concrete. The recent research and applications of the polymer-modified mortar and concrete are comprise of repair systems for deteriorated reinforced concrete structures, strengthening (or retrofitting) methods and exfoliation (or delamination) prevention methods for existing reinforced concrete structures, liquid-applied membrane waterproofing systems, advanced polymeric admixtures such as high-grade redispersible polymer powders and hardener-free epoxy resins, intelligent repair materials, application of accelerated curings, semiflexible pavements, and drainage pavements with photocatalyst. The research and applications of the polymer mortar and concrete are related to new liquid resins, setting shrinkage control, thermal properties and temperature dependence, lightweight or porous polymer mortars and concretes, artificial marble products and precast products. The polymer-impregnated mortar and concrete are mainly concerned with field polymer impregnation techniques using silane-based barrier penetrants.