The Use of Recycled Fine Concrete Powder in Cement Mortar

The recent increase in industrial waste in the construction industry has created a number of problems. One is that the total amount of concrete scrap members resulting from rebuilding currently exceeds 100 million tons. The recently enforced Construction Law for the Promotion of Utilization of Recycled Resources stipulates that at least 95%of concrete scrap must be recycled by the year 2010. This paper examines the fresh and hardened properties of recycled fine powder from river aggregate concrete and limestone concrete when mixed into cement mortar using the following procedures: Test1: To find an effective ratio of recycled fine powder mixed into mortar either as a substitute for fine aggregate materials or for ordinary portland cement ; Test2: To examine the effectiveness of mixing both recycled fine concrete powder and admixture material for flow values at fresh state and for strength of cement mortar. From the test results we can confirm the effectiveness of the combined use of both recycled fine aggregate and fine concrete powder for cement mortar. We should also examine the effectiveness of the use of recycled fine powder for concrete members