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ENVIRONMENT
ADRIENNE METHOD
Technical information
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• ISO/DIS 13472-1
• MEASUREMENT OF SOUND ABSORPTION PROPERTIES OF
  ROAD SURFACES IN SITU
• PART 1 Extended surface method
• final draft project
• Issue of the international standard by the
  end of the year

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• ENV1793-5
• ROAD TRAFFIC NOISE REDUCING DEVICES - TEST METHOD
  FOR DETERMINING THE ACOUSTIC PERFORMANCE.
• PART 5 INTRINSIC CHARACTERISTICS - IN SITU
  VALUES OF SOUND REFLECTION AND AIRBORNE SOUND
  INSULATION
• Draft stage only
• Issue of a test standard before the end of the
  year (valid for about 2 years)
• European standard

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• SCOPE
• Method for measuring the reflection index for
  sound reflection and the sound insulation index
  for airborne sound insulation
• applications
• qualification of noise reducing devices to be
  installed along roads or railways
• determination of intrensec characteristics of
  sound reflection and airborne sound insulation of
  noise reducing devices in actual use
• comparison of design specifications with actual
  performance data after the completition of the
  construction work
• verification of the long term performance of
  noise reducing devices (with a repeated
  application of the method)

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• MEASURING EQUIPMENT
• analyser
• sound source (single loudspeaker)
• microphone (flat response between 100 Hz and 5000
  Hz)
• Loudspeaker-microphone assembly (fixed and stable
  connection between the source and the microphone)
• test signal MLS

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DATA PROCESSING - calibration - sample rate
gt 43 kHz - signal-to-noise ratio gt 10dB -
signal substraction technique - Adrienne
temporal window MEASUREMENT - for noise
barriers, rotation of the loudspeaker-microphone
assembly, vertical or horizontal rotations 50,
60, 70, 80, 90 (reference), 100, 110, 120,
130
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50
LOUDSPEAKER - MICROPHONE ASSEMBLY
90
130
Loudspeaker
microphone
Rotation plane (vertical or horizontal, for noise
barriers only)
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R
I
U
I Direct Incident component
R Reflected component
U Unwanted parasitic component
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SIGNAL SUBSTRACTION TECHNIQUE
I
I
R
U
I Direct Incident component measured in a free
field
R
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dBFA32 MLS
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ADRIENNE TEMPORAL WINDOW - A LEADING EDGE
HAVING A LEFT-HALF BLACKMAN-HARRIS SHAPE AND A
TOTAL LENGTH OF 0,5 ms ( prewindow ) - A FLAT
PORTION HAVING A TOTAL LENGTH OF 5,18 ms
( mainbody , the point where the flat portion
begins is called the  marker point ) - A
TRAILING EDGE HAVING A RIGHT-HALF BLACKMAN-HARRIS
SHAPE AND A TOTAL LENGTH OF 2,22 ms THE TOTAL
LENGTH OF ADRIENNE WINDOW SHALL BE 7,9 ms
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ADRIENNE TEMPORAL WINDOW
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• Then...
• POWER SPECTRA OF THE WINDOWED SIGNAL
• REFLECTION INDEX
• SOUND INSULATION INDEX FOR NOISE BARRIERS
• MEASUREMENT REPORT

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ENV 1793-5, In situ measurement for noise
barriers No dedicated module yet in dBFA, but
all the measurements can be performed with
SYMPHONIE and dBFA32 software with the MLS and
signal edition modules ISO/DIS 13472-1, In situ
measurement for road surfaces dedicated module
of dBFA32 available October 2000
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LYON - NEW YORK - KUALA LUMPUR - ROMA - SAO PAULO
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