Social background

　It is said that there are more than 230km of decks that need to be replaced within the last 10 years due to repeated loads by traveling vehicles, freeze-thaw action in cold regions, and spraying of antifreeze agents. In addition, about 3,000 collapse accidents occur annually due to sewer pipes and other pipes. Sewerage facilities are also said to deteriorate rapidly in the future.

Purpose of the activity 　

Precast concrete products that can reduce the environmental load as well as "shorten the construction period", "reliable construction", and "improve the durability by repair" in the maintenance work to replace the parts whose deterioration has become apparent, using the blast furnace slag, which is a by-product of iron making. To realize.

Outline of activity 　

If amorphous blast furnace slag is used as sand, (1) high frost damage resistance can be obtained, (2) cracks can be reduced, (3) salt penetration can be suppressed to a low level, and (4) high resistance to sulfuric acid can be obtained. It has been clarified that the patent has been granted and a patent application has been filed.

Expected effect 　

Achieves more than 5 times the durability against frost damage, salt damage, and sulfuric acid compared to ordinary concrete. In addition, CO2 emissions from raw materials can be reduced by 35%, and 50% are recycled materials, which enables effective use of resources and reduction of environmental load.

URL

http://conc.civil.okayama-u.ac.jp