The theoretical model to optimize noise barrier performance at the window of a high-rise building

This paper attempts to design the horizontal noise barrier near the window at the building facades. Previous results have showed that the insertion loss by the barrier declines for the occurrence of reflection. In this paper, some remedial measures have been studied using the theoretical prediction by Macdonald's and the image receiver theory. The theoretical model results were verified by the scale models tests. By designing an absorptive top screen using the theoretical models, an insertion loss of 17 dB at a frequency of 500 Hz, 20 dB, at a frequency of 1000 Hz and 25 dB and at frequency of 2000 Hz could be obtained. Such performances are higher than the previous windows screens and are comparable with tall barriers or partial enclosures on the roadside. This is particularly useful in high-rise buildings when tall barriers cannot be built. (C) 2000 Academic Press.