EXPERIMENTAL STUDY ON THE PARTIAL REPLACEMENT OF FINE AGGREGATES WITH PLASTIC IN THE PRODUCTION OF CONCRETES

The project titled “Experimental Study on the Partial Replacement of Fine Aggregates with Plastic in the Production of Concretes,” was carried out with the aim of knowing the effect of partially replacing fine aggregates with plastic waste in concrete production. The aim is twofold: to mitigate environmental impact by repurposing plastic waste and to evaluate the performance of plastic-aggregate concrete. Methodologically, various types of plastic waste are selected and processed to suitable sizes for incorporation into concrete mixes. Comprehensive testing is conducted to assess both the fresh and hardened properties of the resulting concrete specimens. Tests include workability assessments using slump tests, as well as mechanical property evaluations such as compressive tests. The spent plastics were gathered, ground into smaller components, pulverized in order to get granules of plastic lower than 4.75mm size. Sieve studies were carried out for particle size distribution. 9 nos. of 10cm x10cm x10 cm cement concrete Cubes of 1:1.5:3 (C25) mix were cast for 0%, 5%, 10%, 15%, sand being substituted by Pulverized plastic material. Volumetric proportioning was utilized instead of design mix since the density of plastic material was too low. Workability test, weight and compressive strength of the cubes were determined. The results of the study shows that the slump of the fresh concrete decreased with increase in the replacement of the fine aggregate. This implies that the presence of plastic in the concrete decreased its workability. Also, the control sample, with no replacement, exhibited the highest compressive strength throughout the curing periods of 7, 14, and 28 days. As the percentage of sand replacement increased, there was a noticeable decrease in compressive strength. Notably, the replacement of 5% of sand with plastic material showed a gradual decrease, while beyond 10%, the decrease became more significant. This trend is attributed to the inability of plastic waste aggregate to effectively interact with the cement paste, unlike natural aggregate. Recycling of plastic trash with river sand decreases its negative environmental impact of river sand quarries, reduces the depletion of natural resources Based on the findings of this study, it can be concluded that the replacement of natural sand with plastic waste aggregate in concrete production leads to a reduction in compressive strength. However, the similarity in particle distribution between natural sand and plastic material suggests the potential for utilizing plastic waste as a partial replacement for sand without significant compromise in textural properties.