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Achieved investigations Producing noise maps of significant areas of Budapest (till now Moszkva tér) Spectral analysis of noises generated by the traffic Test noise abatement materials in use
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Traffic noises and its abatement
Baár-Madas Secondary School Budapest, Hungary
Our aims are
to make noise maps to determine the noise load of interesting areas
to analyze the traffic noises more deeply to explore the psychical effects to give recommendation for “proper” noise
abatements
Achieved investigations
Producing noise maps of significant areas of Budapest (till now Moszkva tér)
Spectral analysis of noises generated by the traffic
Test noise abatement materials in use
Noise map of Moszkva tér
We gave a complex answer of a noise load of a major traffic junction measuring average, maximum and variance analyse the change in space and time explore the effects of environment
We plotted 2D noise maps
Noise map of Moszkva tér
The hot points (noise > 75 dB)
Reduction effect of the environment
The time evolution of the noise at a typical weekday
Achieved investigations
Producing noise maps of significant areas of Budapest (till now Moszkva tér)
Spectral analysis of noises generated by the traffic
Spectral analysis of noises Spectral analysis (Fourier transformation):
decomposes the noises to sum of sound waves with different frequencies (deep, middle and high voices)
Mathematically:
1
0
2sin2cosˆN
ikn N
kniNknff
the original functionthe Fourier-transformed
Spectral analysis of noises
The spectrum of a tuning fork (“clear”)
The spectrum of a recorder (consists of peaks)
The spectrum of the noise of a car (“dirty”)
Different kind of spectrums:
Spectral analysis of a car
frequency [Hz]
inte
nsity
car
Spectral analysis of a car
frequency [Hz]
inte
nsity
deep voices components
car
Spectral analysis of a car
frequency [Hz]
inte
nsity
middle voices components
car
Spectral analysis of a car
frequency [Hz]
inte
nsity
high voices components
car
Other spectrums
frequency [Hz]
inte
nsity
bus
higher intensity at low,
lower intensity at high freq. components
Other spectrums
frequency [Hz]
inte
nsity
truck
very large deep components
Achieved investigations
Producing noise maps of significant areas of Budapest (till now Moszkva tér)
Spectral analysis of noises generated by the traffic
Test noise abatement materials in use
Testing noise abatement materials
We evaluated the effectiveness of some noise reduction materials in two different respects: the noise reduction capabilities the spectral characteristic of the reduction
We want to find the advantages, disadvantages and common problems
Our test layout
frequency [Hz]
inte
nsity
Spectral noise abatement of glass
without abatementwith abatement
frequency [Hz]
inte
nsity
Spectral noise abatement of glass
effective reducing at high frequencies
poor reducing at low,
wood glass
plastic foam glass in frame
glass
glass in frame
`
The common problem:
Bad abatement capability at
low frequencies
The question:
What are the good materials?
How can we make them?
Planned investigations
Psychical effect of noises Define the characteristic features of “proper”
noise abatement Testing the noise reduction walls in use
noise attenuation capabilities spectral characteristic
Comparing the special national regulations in this field
Participants
Hinsenkamp Anett Lipták György Mészáros Bence Papp Ádám Török Csaba
Thank you
for your
kind attention!
