Impact of recycled plastic aggregate concrete in high-temperature environments

The most critical problem currently affecting humanity is pollution produced by wasted plastic. Plastic is a non-biodegradable substance with a high utility rate; as a result, it is becoming increasingly harmful to the environment. Recycling this type of leftover plastic is a small step toward addressing environmental challenges. Recycled plastic aggregate (RCPA) is being used as coarse aggregates in concrete in current research. This will not only help to lower the cost of coarse aggregates (CA), but it will also save a lot of energy during production, paving the way for sustainable development by reducing the burden on natural resources. The diverse physical properties of concrete are investigated using varying amounts of RCPA at temperatures ranging from 600 °C to 800 °C. CA is substituted by RCPA in proportions of 10%, 20%, 30%, and 40% by weight of CA. Concrete's optimum strength is obtained at a 30% replacement quantity. The density of concrete made using recycled plastic aggregates was reduced by 16% to a control mix. The workability of concrete including recycled plastic aggregate was lowered due to the uneven and irregular form of the aggregates. There is a maximum reduction in workability of 14%. Compressive strength, flexural strength, and split tensile strength all increase to their maximum levels of 5.3%, 12.9%, and 19%, respectively, when 30% of aggregate is replaced by RCPA. Due to a decrease in bulk density of mixes and adhesive strength between cement and RCPA, the strength of concrete gradually deteriorates. Principal component analysis (PCA), multiple linear regression (MLR), and response surface regression confirm the experimental findings (RSR). The PCA explains 70% of the variability in the data, which is excellent for predicting concrete strength. Both the MLR and RSR statistical models are best fitted to the experimental data, but the RSR statistical model's findings are fairly good, and it is better matched to the data than the MLR model, and the RSR model's regression coefficient is also greater than the MLR model's.