Comparative Analysis of Natural and Recycled Coarse Aggregates Using IS Code Method and Tarantula Curve Method in Concrete

Concrete is a manmade wonder, being used after air and water as the third largest material. Content of concrete, the cement is responsible for 5% plus global greenhouse gases evolution. The mix of cement must be limited or evaluated cautiously in concrete leading to sustainable growth, without compromising quality and strength. Aggregates are responsible for body and strength in concrete. Selection and gradation are paramount along with cement for concrete overall performance. When these ingredients are selected using new methods like the Tarantula curve method and the tradition IS code method, comparisons show they are very similar in evaluation of strength and overall performance. The shortage and natural aggregates and their nonstop demand has caused concern, recycled concrete aggregates on the other hand are produced enormously and have proved to have similar strength as natural aggregates. In this work, slump cone test and other parameters proved that both are showing the same results for workability once the fine aggregates are quantified. Water to cement ratio for natural and RCA is responsible for good workability and impacting other engineering properties. Cement content on the RCA and natural aggregates causing changes in strength due to surface effect is evaluated in this work. The results show that 7-day strength for the RCA and NA are nearly similar whereas the 28-day final strength for the NA is more as compared to RCA. The IS code method and Tarantula curve method for the evaluation of compressive strength, split tensile strength indicates that both fits better and resembles similar strength. The pavement quality concrete can be produced using these two new methods with multiple combinations of NA and RCA is proved in the work.