D5 Annex report WP 3: ETIS Database methodology ... - ETIS plus

D5 Annex WP 3: DATABASE METHODOLOGY AND DATABASE USER MANUAL – FREIGHT TRANSPORT DEMAND
Indicator Compilation Template No. 15
Ref. 1.3.3
Definition
ETIS Glossary
Computation Method (Formula)
Noise levels generated by road transport + corresponding marginal unit
Noise generate by a link in Watts/ Exposure to over a specific noise level in dB
A general approach has been defined in COMMUTE. The default reference conditions are as follows;
· average vehicle speed, v ­ 75 km/hr
· percentage heavy vehicles, p ­ 0%
· percentage uphill gradient, g ­ 0%
The formula used to derive the combined average vehicle speed and percentage heavy vehicles correction is as follows;
· correction (multiply by): (v+40+500/v)^ 3.3 x (1 + 5 p/v)/7604424
The formula used to derive the percentage uphill gradient correction is as follows;
· correction (multiply by): 10^ (0.03g)
The formula to calculate average sound intensity in watts/m 2 at any given radial distance, r, and ignoring excess attenuation is as follows. For road traffic noise
the standard reference radial distance, d, is 10 m from the side of the carriageway, which is 13.5 m from the centreline of vehicles moving along the road;
· sound intensity = sound power per metre/(p x d)
· sound pressure = square root (sound intensity x 415)
· sound pressure level = 20 x log(sound pressure/0.00002)
· link sound power= number of vehicles*corrected source sound power
· corrected sound power= reference sound power per vehicle per hour*heavy vehicles correction factor* uphill gradient correction factor
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Document2
27 may 2004