Article

Speed Bumps Impact on Motor Transport Noise

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Abstract

Most accidents are caused by excessive speed or aggressive driver behavior. One of the most popular speed regulation implement is speed bumps. However, there are some problems with speed bumps as well – it has been noticed that speed bumps increase motor vehicle-induced noise. This article presents investigation on how speed bumps increase motor vehicle-induced noise. The investigations were carried out on Klaipėda and Vilnius streets during different time of the day and year. Brüel&Kjær sound level meters type 2260 and 2270 were used to investigate how much noise is caused by vehicles passing different types of speed bumps.

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... Speed table in Asanavičiūtė street is made of asphalt. Similar studies inside the buildings were not found (Januševičius, Akelaitytė 2015). ...
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'LeiStra2' is a research program aimed at reducing road traffic noise at the source. It is a governmental funded program which comprises three parts: low noise tires, low noise roads and verification of results. In the course of the program it was possible to develop a new low noise truck tire, which has the potential to become the most quiet available truck tire. In another sub project a physical verified finite element method (FEM) software tool was developed, that is by now capable of simulating the structural vibration and noise emission from slick tires rolling on real road surfaces and thus can be used for the computer aided design of low noise tires. Current research in this sub program deals with the influence of the tread profile on the noise generation. In the research on a low noise road, a modified stone matrix asphalt pavement was realized that shows a noise reduction of 2 dB compared with conventional stone mastix asphalt. Furthermore, it is well know that porous asphalt layers have high sound absorption abilities, but unfortunately typically loose this ability after about eight years due to dirt clogging the pores. Within LeiStra2 we developed two measures that help to keep the sound absorbing abilities for a longer period. In particular the surface of the voids of the porous asphalt were covered with special polymeric material to prevent the voids from being clogged. In another sub project additional reactive sound absorbers were embedded in porous asphalt, which enhances the sound absorption and reduces the tire rolling noise by about 3 dB. Particularly annoying is the noise originating from vehicles rolling over expansion joints. Within LeiStra2 we succeeded in developing a new surface structure for conventional expansion joints, which substantially reduces the noise emission. These measures will be tested on various test tracks under real traffic load and environmental impact, which is the third subject of the program, the verification of the results. The program will be finished in summer or autumn 2009.
Article
The majority of acoustic impact studies developed over the last 50 years have used a similar acoustic parameter (L(eq), L(dn)) but the noise mapping methodology has been very uneven. The selection of the measurement points, the measurement periods, or the evaluation indices have not followed a unique criterion. Therefore, it is not possible to compare the sound pollution levels between different cities from those studies, at least in a rigorous sense. Even more, different studies carried out in the same city by different researchers during different years and using different methodologies are not conclusive whether the acoustic pollution increases or decreases. The present paper shows results, with statistical significance, about the evolution of the acoustic pollution obtained for two Spanish cities, Pamplona and Madrid. In both cases, it can be concluded that noise pollution decreases over time (P<0.01).
Article
The effects of vehicle speed variation on road traffic noise are analyzed. The steady speed motion is replaced by deceleration, cruise, and acceleration. Because of a relatively loud acceleration noise, such a speed variation results not only in the noise decrease zones, but in the noise increase zones as well. The location of these zones depends slightly upon the ground covering (grass, concrete, etc.). Conversely, their boundaries change dramatically with the parameters describing noise emission during deceleration, cruise, and acceleration. For example, the Japanese and Polish models of noise emission have been applied. The critical length L(*) of the cruise segment of the road is introduced: for L>L(*) the sound energy decline (due to speed reduction) compensates the sound energy growth (due to acceleration). The results obtained could be useful for road administrators.
Automobilii} keliamo triuksmo tyrimai, Mokslas -Lietuvos ateitis
  • R Blazys
  • G Garbincius
  • Z Dabuzinskaite
  • I Gedzevicius
Blazys, R.; Garbincius, G.; Dabuzinskaite, Z.; Gedzevicius, I. 2009. Automobilii} keliamo triuksmo tyrimai, Mokslas -Lietuvos ateitis. Vol. 1. No. 6.
The Use of Speed Bumps in Residental Areas Noise Pollution Impacts
  • N Elioy
  • C Vogiatzis
Elioy, N.; Vogiatzis, C. 2013. The Use of Speed Bumps in Residental Areas Noise Pollution Impacts. Available from Internet: http://www.este.civ.uth.gr/en/papers/THE%20USE%200F%20
Perspective of the Soundscape Ap proach as a Tool for Urban Space Design
  • G Brambilla
  • L Maffei
Brambilla, G.; Maffei, L. 2010. Perspective of the Soundscape Ap proach as a Tool for Urban Space Design, Noise Control Engi neering Journal 58(5): 532-539. http://dx.doi.org/10.3397/L3484180
Low Noise Road Traffic' -the Germ an re search program "LeiStra2
  • A Lorenzen
Lorenzen, A. 2009. Low Noise Road Traffic' -the Germ an re search program "LeiStra2", Noise Control Engineering Journal 57(2): 148-15. http://dx.doi.org/10.3397/E3081316