Japan Partnership for Circular Economy

Japan Partnership for Circular Economy


Concrete with Recycled Cement using Waste Fresh Ready-Mixed Concrete Sludge. 「Eco-Crete R3」

[Company / organization] Kajima Corporation


Concrete work involves unavoidable waste of about 1% to 2% of the ordered concrete and there may be surplus. When surplus concrete is returned to the ready-mixed concrete plant, the aggregates are removed and the remaining cement content(sludge) is discarded as industrial waste.

Outline of Eco-Crete R3

Eco-Crete R3 is concrete produced by using recycled the sludge that has been dried and pulverized as admixture (CemR3). Eco-Crete R3 is used for ready-mixed concrete and precast concrete products. This concrete recycling technology contributes to reduction of CO2 emissions and waste, and is a result of joint research by Kajima Corporation, Sanwa Sekisan, Ltd., and Tokai University.


Eco-Crete R3(Ready-mixed concrete) was applied for the first time to actual construction, confirming the practical level competitiveness in terms of quality and cost. The social implementation of this technology has been realized by commercializing competitive product that combine environmental performance, high quality and superior economic efficiency, and established an advanced “local production for local consumption” model of the recycling system in Kanagawa.