Research On Noise Reduction Characteristic Of OGFC

Long-term noise would affect and damage people’s health and the public have taken noise as a kind of environmental hazard seriously. Reducing noise resulting from car tires and pavements is a important measure to reduse traffic noise. Open Graded Friction Course(OGFC) has a good noise reduction performance. To design better asphalt pavements, studying on the noise reduction behavior of OGFC and finding factors affect pavement noise is necessary.Driving Wheel Pavement Analyzer is used to test noise resulting from car tires and pavements more accurately and Matlab software is used to build a virtual A-weighted sound level meter to process noise data in real time. Collected noise data is time domain waveform displayed, gross calculated and spectral analysed and the software is stable, reliable, structure-simple and with high performance- price ratio. Laboratory tests of the effect of running speed, wet conditions and texturedepth on noise reducing behavior of OGFC and long-term performance are conducted. This paper measures the tire/pavement noise of OGFC, AC, SMA and Micro-Surfacing and anlayzes their noise reduction mechanism.Meanwhile, based on the spot noise measurement, OGFC reduces more noise in Medium-high Frequency than AC, which is similar to laboratory test results. The porous structure of OGFC decreases air pumping. In the end, analyzing the internal noise of OGFC, AC and SMA, with greater low frequency OGFC reduces noise more between frequency 1000 Hz and 4000 Hz compared with AC and SMA. For evaluating internal noise better, the paper adopts loudness, NR,PSIL and perceived noise level.