Engineering Properties of Television Plastic Shell Waste (TPSW) to Replace Part of Sand–Cement Mortar

Adding domestic waste into cement mortar or replacing fine aggregate can effectively reduce the use of natural sand and gravel and reduce carbon emissions, thereby preventing waste from polluting the Earth’s environment. This study explored a sustainable method for recycling television plastic shell waste (TPSW) by using it as a partial replacement for sand in cement mortar production. By evaluating water–cement ratios (0.4, 0.5, 0.6), ages (3, 7, 28, 56, 91 days), and TPSW levels (0%, 5%, 10%, 15%), this research assessed key properties, such as the slump, compressive strength, and durability. The results show that the TPSW absorbed less water than natural sand, increased the number of pores and slightly reduced the strength. However, a 5% substitution led to a minimal performance loss after 91 days, while it improved the sulfate resistance and resistivity. Overall, incorporating 5% TPSW reduces the environmental impact and carbon emissions, offering a sustainable solution for cement production.