Surface Area Model to Assess the Plastic Aggregate Concrete Properties

In this study, a model was proposed based on calculating the total surface area of aggregate to assess fresh density, compressive, and splitting tensile strengths of plastic aggregate (PA) recycled concrete. The key factor is the change in the total surface area of the natural aggregate by the PA. For a given PA volume, the change in the property could be assessed. The prediction well depends on the natural and plastic aggregates distribution size, specific gravity, and bulk density. The proposed model prediction was accurate when applied to high-strength, and lightweight concretes. The reason is attributed to the relatively good bond between PA and hardened cement paste in these concretes. However, for the majority of concrete mixes investigated, the model moderately underestimated strength loss, and this underestimation could be attributed to the PA- hardened cement paste bond deficiency. An attempt was made to assess the bond deficiency parameter for a more accurate prediction.