This study examines air, recycled plastic grains, fibers from rubber shreds and sawdust fibers as sound insulation materials to attenuate sound produced from continuous working lab fatigue test machine. These waste materials are filled in between a double glazed-aluminum framed box. The sound attenuation is tested at three studied 0.5, 1.0 and 1.5 m distances. Since the sound wave is propagated in three dimensions, the experimental work is employed in four upper, fronts, motor and sample fixture side directions. Moreover, the study is extended to examine temperature increase due to enclosing. Tests of sound level are carried out with closed and opened inlet and outlet designed slotting according to a box size. Gradual sound attenuation reaches 18, 20, 22 and 25% for air, plastic grains, rubber and sawdust fibers, respectively. The present work proves that waste materials are efficient in noise removal from sound sources. Also, they help the environment cleanliness from synthetic disposable bottles and tires as well as bio-wood wastes and assist the sustainability of earth.
Testing of the ability of fatigue test machine prototype and fatigue test for nylon and cast iron specimens
