Recycled construction and demolition concrete waste as aggregate for concrete

Abstract

Concrete is the most largely consumed construction material worldwide. The Portland cement and concrete is a major consumer of natural resources. Rate of development of infrastructure has increased year by year. Regular use of aggregates for making concrete cause depletion of natural resources like rock, minerals etc. we know these natural resources are limited and cannot be developed further again and again. Besides of this the production of raw materials used in concrete such as aggregate and Portland cement requires a significant amount of energy input and causes various environmental problems (e.g., emission of greenhouse gases).The “green” concrete is defined as the concrete produced by utilizing alternative and/or recycled waste materials which are eco-friendly so that can reduce energy consumption, environmental impact, and use of natural resources.One of major issues associated with “green” concrete are what can be alternatives/waste for replacing conventional aggregate and  how the alternative/waste materials affects concrete properties compared with the conventional Portland cement concrete. Another important issue is “the benefits and barriers of producing “green” concrete” by replacing conventional aggregate. This paper first discusses suitability /potential benefits of using alternative and/or waste materials as aggregate in concrete production, followed by a review of previous studies on “green” concrete.This paper further investigates what are the different alternative/waste materials that can be used as aggregate by replace conventional aggregate in concrete production, followed by a review of previous studies on “green” concrete.In last it discusses barriers in using alternative/waste materials.