Development of a Sustainable Concrete Waste Recycling System - Application of Recycled Aggregate Concrete Produced by Aggregate Replacing Method

Y. Dosho Journal of Advanced Concrete Technology, 5(1) 27-42, 2007 The generation of huge amounts of construction waste is anticipated due to the demolition of older structures such as power stations built more than 30 years ago. On the other hand, the reuse of construction waste is highly essential from the viewpoint of Life Cycle Assessment (LCA) and effective recycling of construction resources. In order to promote the reuse of construction waste, it is necessary to achieve three basic concepts: (1) assurance of safety and quality, (2) decrease of environmental impact, and (3) increase of cost effectiveness of construction. This paper outlines the development of a recycling system, application of recycled aggregate concrete produced by the aggregate replacing method, which is effective in reducing both cost and environmental impact from the viewpoint of LCA for concrete waste generated by the demolition of large-scale buildings such as powerhouses. Result of this study showed that recycled aggregate concrete using the aggregate replacing method can acquire sufficient quality as structural concrete and/or precast concrete products through material design based on the value of relative quality method. Moreover, with the adoption of the developed recycling system, it was confirmed possible to recycle concrete waste produced from the demolition buildings in a highly effective manner reducing both recycling cost and environmental impact.

This paper addresses an increasingly important problem of concrete aggregate recyling and proposes a industrial scale recycling system. The paper describes the societal impact of this research, and methods for assuring the quality of the resulting concrete containing recycled aggregates. (Prof. Victor Li, University of Michigan, USA) The paper reports the development of a recycling system which makes effective use of concrete waste from demolition of old structures. An aggregate replacement method is proposed, which lessens the environmental impact due to the production of concrete. The quality control of recycled coarse aggregate concrete is well researched and application is illustrated by two projects. The work contributes to a green and sustainable construction that is of current relevance. (Prof. Kiang Hwee Tan, National University of Singapore, Singapore )