Properties of Recycled Polystyrene and Polypropylene Bounded Concretes Compared to Conventional Concretes

Thermoplastic recycled polystyrene (rPS) and polypropylene (rPP) bounded concretes were formulated by thermal curing. Mechanical properties, thermal crack-healing efficiency, and moisture and temperature susceptibility of the rPS-bounded and rPP-bounded concretes were evaluated with respect to portland cement and asphalt concretes (PCCs and ACs, respectively). The rPS-concrete exhibited a compressive strength slightly higher than that of the ACs. In contrast, rPP-concrete possesses much higher compressive strength, approximately threefold that of the ACs, which is almost equivalent to the strong PCC. However, rPS-concrete demonstrates the highest bending resistance, more than the ACs and twice as rigid as the PCCs, while rPP-bounded concrete was only stiffer than the ACs. The rPS-concrete exhibited flexural strength greater than both the PCCs and the ACs, and the rPP-bounded concrete showed approximately threefold and fivefold bending strength of the PCC and ACs, respectively. A simple