Investigation of noise barriers enhancement efficiency for attenuation of low frequency traffic noise

This paper presents investigation of traffic noise barriers enhancement potentiality at low frequencies: re-garding measurements results near motorway with 43.3-49.8 percentage of heavy duty, the investigation assesses efficiency of existing (modelled and built according pre-dicted overall A-weighted rated sound levels) noise barriers and simulates (using finite element method) improving of them by adding most common T-shape and octagon-shape tops at low frequencies. According simulation results (model deals with divergence loss, diffraction from obstacles, absorption and reflection from surfaces of cylindrical sound waves), noise barrier enhancement with those tops has influence on additionally 0.6-6.5 dB reduction of SPL at low frequencies in a noise shadow zone. DOI: http://dx.doi.org/10.5755/j01.mech.21.1.10137