Experimental and Numerical Evaluation of Recycled Thermoplastic Composites for Structural Applications in Sustainable Construction

This study presents an experimental and numerical framework for evaluating recycled thermoplastic composites for structural applications in sustainable construction. The base material (BM), comprising recycled high-density polyethylene (HDPE), low-density polyethylene (LDPE), and polypropylene (PP), was characterized in tension and compression; inverse mechanical identification yielded assigned domain fractions of 26%, 36%, and 38%, respectively. Numerical incorporation of acrylonitrile butadiene styrene (ABS) resulted in an optimized composite (CMo: 13% HDPE, 18% LDPE, 19% PP, and 50% ABS), increasing the predicted tensile elastic modulus from 871.36 MPa to 1670.4 MPa (91.7%). Thermal modeling illustrated the BM temperature distribution under prescribed boundary temperatures, while a preliminary structural assessment considered CMo beams, columns, and roof-support members for single-story housing and identified insufficient lateral stiffness under seismic loading. An inventory-based comparison yielded approximately 59% lower estimated CO2-equivalent emissions for the CMo structural system than for the reinforced-concrete and steel reference, subject to the adopted emission factors and differing source boundaries. The framework supports formulation selection for further investigation, although experimental validation of the CMo, members, and connections remains necessary before structural suitability can be established.