Reza Saghafi

Noise can be reduced by sound barrier materials. Sound transmission measurements are used to determine the insulation performance of sound barriers. In this work, sound transmission behavior of needle-punched nonwoven fabrics produced using staple polypropylene fibers in terms of various variables such as fabric mass per unit area, needling parameters, fiber distribution and air permeability was investigated. Samples of needle-punched fabrics were produced using at various punch-densities and needle penetration depths. Statistical analysis was used to predict the transmission of sound through the samples. The statistical analysis pointed to the effect of constructional and mechanical properties on sound transmission of the samples. Results also indicated that the most influential parameters that affect the fabric transmission are fabric mass and air permeability.