Melted Electronic Waste Plastic as an Alternative to Cement in Pavement Block Manufacture: A Study of Mechanical Properties

The viability of using melted electronic waste (e-waste) plastic as a complete replacement for cement in the production of pavement blocks is examined in this study. The study compared the compressive strength, split tensile strength, water absorption, and heat resistance of pavement blocks made from e-waste plastic to those made from cement. The experimental procedure involved producing two different batches of pavement blocks. One batch used melted electronic waste (e-waste) as a binder, while the other used Portland cement at a ratio of 1:3. A total of 28 blocks were produced in each batch for the investigation. River sand was collected from a construction site near Windy’s Hostel at Windy Ridge in Takoradi. The particle size distribution of the sand used in this investigation was determined by a grading test procedure according to the British Standard method. In accordance with the British Standard method, the compressive strength test was done to determine the compressive strength of the pavement blocks. After 28 days of curing, the results of the compressive strength tests showed that the pavement blocks made from e-waste plastics achieved a compressive strength of 41.3 MPa, while the cement pavement blocks achieved a compressive strength of 39.2 MPa. The split tensile strength tests conducted after 28 days of curing revealed that the e-waste plastic pavement blocks achieved a tensile strength of 5.5 MPa, whilst the cement pavement blocks reported a tensile strength of 3.2 MPa. This suggests that the e-waste plastic pavement blocks are suitable for use in low-load-bearing applications. The study also revealed that e-waste plastic pavement blocks absorbed water at a rate of 0.46% whereas the cement pavement blocks absorbed water at a rate of 1.33% after 24 hours of full immersion. This demonstrates the resilience of e-waste plastic pavement blocks in wet conditions, reducing their susceptibility to degradation over time. Moreover, the heat resistance test conducted indicates that the e-waste plastic pavement blocks started to deform after 1 hour at a temperature of 150°C, whilst the cement pavement blocks showed no physical change up to 150°C. The findings of this research suggest that the melted e-waste plastic may be a viable alternative to cement in the production of pavement blocks for use in areas with a temperature of <140°C. Further research may be necessary to investigate the heat resistance of e-waste plastic pavement blocks for usage in a wider range of environmental conditions.