The Sustainable Use of Plastic Waste in Engineering and Sewer Pipe Applications

This study assessed the use of plastic waste in engineering applications where sulfuric acid attack is crucial, namely, pipes. Cubic specimens were prepared by simultaneously heating and mixing disposed plastic bottles and containers with sand at a temperature that would melt the thermoplastic materials and achieve a uniform fused mix, known as plastic-based cementitious (PBC). Specimens were subjected to sulfuric acid solutions and then tested to determine volume changes, mass changes and compressive strength. Small size pipe samples were molded and tested for maximum bearing strength by the two-edge bearing test and for tensile strength using the indirect tensile strength. The laboratory results revealed that PBC specimens produced with sand had a compressive and tensile strength as high as those using ordinary Portland cement and that small size pipes provided acceptable bearing strength. PBC pipes were also tested for sulfuric acid attack. Findings showed that PBC pipes were highly resistant to sulfuric acid attack. PBC not only has the mechanical properties of concrete and performs well in sulfuric acid solutions it also utilizes recyclables plastic that would otherwise end up in landfills.