Influence of Absorption and Insulation Properties for Phonic Treatment of Public Works Equipment

This study presents the problem of designing, manufacturing and testing of some protective systems made from composite materials which can simultaneously perform the next requirements: noise absorption for middle and high range frequencies, noise insulation for low frequencies, vibration damping in order to avoid noise transmission by structure and finally, modularity and adaptability for using to different types of public works equipment, also for other technological equipment with a high level of noise, vibration and mechanical shocks. Decreasing of sound and vibration global level inside and/or outside the public works equipment’s cabin as well as the reduction the noise pollution or the pollution due to the vibration and mechanical shocks on construction site is an actual matter, especially for the countries –last became members of EU; these countries must harmonize theirs national legislations regarding the environment pollution and the labor protection with the EU Directives. The article presents the experimental data of four composite structures with noise absorption and insulation features and three case studies of global level noise reduction inside the cabin for a vibrating compactor, a crawler excavator and a frontal loader