International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 07 Issue: 05 | May 2020 www.irjet.net p-ISSN: 2395-0072 © 2020, IRJET | Impact Factor value: 7.529 | ISO 9001:2008 Certified Journal | Page 515 “Influence of Recycled Concrete Aggregates on Strength Properties of Concrete” Siddharth Pastariya 1 , Raghvendra Singh Parihar 2 1 Assistant Professor, Department of Civil Engineering, Sri Aurobindo Institute of Technology Indore M.P 2 M.Tech Scholar, Department of Civil Engineering, Sri Aurobindo Institute of Technology Indore M.P ------------------------------------------------------------------------***------------------------------------------------------------------------------ Abstract: To avoid the pollution and reuse the material natural coarse aggregate is replaced by recycled aggregate. By the use of recycled aggregate it is possible to reduce carbon di oxide. The recycled aggregate are eco-friendly to the environment. In this research covers the how to choose a material for recycled aggregate In this study the natural aggregate replaced by recycled aggregate in different percentages (0%,20%,40%,60%,80%,100%). The percentage of recycled aggregate mixed in the definite proportion it improves the property of fresh and hardened concrete like, flexural strength & split tensile strength test up to optimum percentage. From the laboratory test results indicates that the compressive strength of these mixtures goes on decreasing, however up to the 20% replacement level, it achieves target mean strength. Hence, for the structural concrete Natural Aggregate can be replaced by the Recycled Aggregate up to 20% range. Keywords: Recycled aggregate, Specific flexural strength, tensile strength, Ultrasonic Pulse Velocity, NDT 1. INTRODUCTION To get sustainable issue in construction area, researchers and company center on using waste concrete as a fresh construction material. It is called recycled aggregate (RA) which can be produced by concrete crusher. Using RA has big opportunity to maintain healthy atmosphere, the properties and characteristics of RA has not been fully investigate so far. While it is hard to regulate the characteristic of RA, every researcher who study recycled aggregate must execute experiment of their concrete, which will be used for RA, to increase the characteristics of their specimens. The quality of RA could be different by its parent concrete because the parent concrete was planned for its purpose such as permeable, durable and high strength concrete. For example w/ratio of concrete will give an impact on water absorption capacity of RA which is correlated to uniqueness of concrete issue such as durability, permeability, strength and elastic modulus. There is a remarkable turn down in high-quality aggregate accessible for construction use. Globally aggregate use is estimated to be 10-11 billion tonnes every year, of this, about 8 billion tonnes of aggregate (sand, gravel, and crushed rock) are being used in PCC every year. The environmental impact of devastate concrete is considerable. Not just is there the environmental impact of transport the waste concrete away from the location but the waste concrete also fill up precious space in landfills. Construction and demolition waste makes up a large portion of all generated solid waste. The charge of worth aggregate has enlarged beyond the rise rate and it is expected that this tendency will carry on as additional limitations are placed on this source in the future. Concrete construction and demolition waste will be recycled if it is less expensive than disposing of it in a landfill and RAC will be used if it is less costly than natural aggregate of comparable quality. RAC use is based on financial side, together with the charge of transport construction and demolition waste and natural aggregate, the charge of construction and demolition disposal, and government intervention on tipping fees and mandatory usage through legislation. Around 60% of aggregate charge is due to transportation. 2. MATERIAL USED 2.1 Cement: In this research work, OPC conforming to IS: 8112-1989 is used. The properties of cement used are shown in Table 1. Table 1: Properties of cement Physical Property Result Fineness of cement 9% Normal Consistency 27%