Principle

The DEUFRABASE is based on the calculation of A-weighted equivalent sound level (LA,eq) in open-field, function of the pass-by sound pressure level LA,max that has been experimentally measured on a given pavement.

The DEUFRABASE allows the calculation of the following indicators:

• LA,eq,1h, the A-weighted equivalent sound level based on the 1 hour-traffic of passenger cars (PC) and heavy trucks (HT)
• LAeq,24h, the A-weighted equivalent sound level based on the traffic distribution pf PC and HT over the 24h of a day;
• Lden, the day-evening-night A-weighted equivalent sound level, calculated from the LA,eq,24h

These indicators can be estimated for each situation (geometry, meteorological conditions, road traffic) and each pavement family.

This procedure [BÉRENGIER, 2000] needs the knowledge of the following information:

• the traffic distribution during the day [6:00-18:00], evening [18:00-22:00] and night [22:00-6:00] periods for each vehicle class, i.e. the passenger cars (n_PC) and heavy trucks (n_HT),
• the number and width of traffic lanes,
• the reference speed of each vehicle class (V_Ref) [V_Ref=90 or 110 km/h for the passenger cars and V_Ref=80 km/h for the heavy trucks],
• the A-weighted pass-by maximum sound pressure level LA,max (in global or third octave values) at a reference microphone located in the road vicinity, 7.50 m from the right lane axis and 1.20 m above the road surface, for each vehicle class, according to the SPB method [EN-ISO 11819-1],
• different geometries with different input parameters.

NEXT : Noise Level calculation

References:

• [BÉRENGIER, 2000] M. BÉRENGIER, Y. PICHAUD, J.-F. LE FUR, “Effect of low noise pavements on traffic noise propagation over large distances: influence of ground and atmospheric conditions”, Internoise 2000, Nice, France (2000).
• [EN-ISO 11819-1] EN-ISO 11819-1, “Acoustics - Method for measuring the influence of road surfaces on traffic noise - Part 1: The Statistical Pass-By Method” (1997)