The acoustic performance of an inclined barrier for high-rise residents

The objective of this paper is to develop a scale model to analyze the perf ormance of the inclined barrier design. A computer program was used to outl ine the zone of noise variation with the tilted angle of a barrier. The res ults of this study show that the average noise level at lower receivers beh ind the nearside barrier could be reduced by 4.6 and 10 dB for 125, 250 and 500 Hz, respectively, by tilting the angle of the farside barrier by over 10. This result seems to be sufficient to counteract the reflected noise pr oblems at lower receivers. It is also noted that degradation is smaller for low frequency. The simple image source and virtual barrier model computer program can help us to locate the critical reflection zone with different t ilted angles of the barriers. Based on the image source model, appropriate improvements of inclined barrier can be designed easily by using geometrica l drawings without calculation. (C) 2001 Academic Press.