Explore the Common Measuring Errors and Quantify the Errors of New Noise Barrier Designs for Mitigating Traffic Noise

Background and Objective: Noise pollution from road traffic has been a persistent problem in Hong Kong and there has been increasing attention on its association with risks to human health and well-being. Much research has been done in searching for an improved design of noise barriers as a direct noise abatement solution. Reflecting on the experience of supervising a recent acoustic barrier design project involving open field tests and using prototypes, this paper aims to explore the common errors in working and performing experiments with scaled models.

Materials and Methods: The project team conducted tests in an open field for the three designs of noise barriers. Amplifiers were used to mimic traffic noise of 800-1200 kHz. The 3-D printing was deployed to make templates for casting concrete panels for their noise barrier models.

Results: Test results showed some inconsistency with the teamʼs expectations. All models were capable of reducing sound at all the measurement points of different heights. At lower heights, the reduction was 4 to 11 dB(A), At higher heights, the reduction decreased to only 3 to 5 dB(A). When the data were plotted on a graph, sound measurements of all three designs showed a non-linear path by height. Therefore, it was difficult for the team to draw convincing conclusions from them. There are lessons learned at every stage of the project, from idea formulation to prototyping and experimentation.

Conclusion: Hopefully, these lessons and suggested resolves will help in the future, especially those involving the use and testing of scale model prototypes.