Strength and Stiffness of Recycled Concrete Aggregates

Abstract

As the construction is in its highest pace, the demand of raw material especially coarse aggregate is in great demand. At the same time the renovation, demolition and refurbishing of old structures is a continuous process, it is resulting in significant source of recycled concrete aggregate (RCA). Bit uncertainty and great variation in properties of RCA has restricted its wide use in all engineering construction activities. From point of view of conservation of natural resources, use of recycled concrete aggregate reduces use of natural aggregates, utilization of waste and results in energy saving. Thus extensive study is carried out to ascertain the effects of use of recycled concrete aggregate (RCA) on strength and stiffness of concrete. The rejected precast concrete, unused ready mixed concrete and concrete from demolished old structures is considered for RCA. Compressive strength and stiffness gain tests are conducted for both natural and recycled concrete aggregate (RCA) is carried out and the results are presented in this paper. Direct volume replacement method is used for replacing a selected quantity of natural coarse aggregates (NCA) by an equal volume of recycled concrete aggregate (RCA).