traffic noises and its abatement baár-madas secondary school budapest, hungary

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!