Development of Stress- Strain Curves for Recycled Aggregate Concrete

Conservation of natural resources and rapid urbanization has prompted growing demand for natural aggregate by construction industry. This demand is compounded by considerable decline in the availability of good quality natural aggregate and enormous increase in the quantities of demolished concrete. The alternative materials to cement in terms of fly ash and other pozzolanic materials were evolved, popular alternative material to coarse aggregate are being explored. Recycled aggregate is one such alternative and the present research work is a step forward in developing the design parameters using stress block parameters.The objective of present investigation is to develop stress – block parameters for the design of reinforced recycled aggregate concrete members. To arrive at the objectives defined above, a comprehensive experimental programme was undertaken. The influence o replacement ratio, (Rr) the ratio of recycled coarse aggregate to total coarse aggregate (Rr=RCA/TCA) on mechanical properties of recycled aggregate concrete was studied. The scope of the investigation programme is defined to generate stress strain test data of concrete, viz; M15, M20, M25, M30, and M35 and five replacement ratios, viz; 0, 0.5, 0.75, 0.85, and 1.0 were considered. A total of 150 cylinder specimens’ were cast for the stressstrain characteristics of hardened concrete.