Optimization of the Bulk Specific Gravity of Plastic Waste Bituminuous Binder using Box-Behnken Design

Waste management and disposal has been an increasing challenge for various industries. Of the wastes that are abundant in the community, plastics prove to be a major problem posing threats to the environment and societal health. As an outright solution, recycling and incorporating plastics to numerous construction materials have been explored in various studies for their potential improvement. This paper aims to generate a mathematical model that predicts the interaction among significant parameters such as plastic concentration added in the mixture, mixing temperature, and plastic particle diameter, and produce the optimum bulk specific gravity of the Plastic Waste Bituminous Binder (PWBB) in hot mix asphalt using the Box-Behnken Design (BBD) of the Response Surface Methodology (RSM) via Sigma XL software. Experimental results show that the multi-linear regression model obtained a correlation coefficient of 0.9878, indicating that the probability plot of the residuals fits the regression line. Ultimately, for the output of the optimization, it was found out that the model with a combination of 7.43 mm particle size, 8.32% concentration of plastic added at 160C yields the maximum bulk specific gravity of 2.52.