Mechanical Properties of Sound-Absorbing Walls from High-Density Polyethylene Plastic Waste

Abstract

This research aimed to: 1) test the mechanical properties of mortar mixed with high-density polyethylene (HDPE) plastic waste; 2) test the mechanical properties of concrete blocks mixed with high-density polyethylene plastic waste, and 3) test the sound absorption of the wall mixed with high-density polyethylene plastic waste. Method of conducting an experimental study by using plastic waste remaining from the production process, namely high-density polyethylene plastic (HDPE), mixed to replace 10% of sand. The mechanical properties of mortar and concrete blocks were examined, and the sound absorption of walls was also evaluated, considering the possibility of their practical use in construction work. The findings revealed that: 1) Mortar mixed with 10% HDPE plastic waste had the highest compressive strength and tensile strength properties, which are 251.45 and 42.27 kg/cm², respectively, but lower than the standard mortar, with values of 334.28 and 48.10 kg/cm², respectively. 2) The mechanical properties of concrete blocks that were mixed with 10% HDPE plastic waste resulted in a compressive strength of 53.03 kg/cm², which is lower than the compressive strength of standard concrete blocks at 54.93 kg/cm². The mechanical properties of concrete blocks mixed with 10% HDPE plastic waste resulted in a compressive strength of 53.03 kg/cm² lower than that of standard concrete blocks at 54.93 kg/cm². 3) The wall mixed with 10% HDPE plastic waste absorbs sound at 500 Hz, reduced to 1.19 dBA, compared with the standard concrete block wall. The frequency at 1,000 Hz could absorb 7.69 dB, which was less noisy than a standard concrete block wall. In addition, the frequency at 1,500 Hz could absorb 17.03 dB, which is less noise than a standard concrete block wall. It is an added value for construction material products made from environmentally friendly plastic waste.