Quiet Pavement

ASPHALT:

THE STRONG, QUIET TYPE

www.AsphaltAlliance.com

Quiet Pavement

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The Decibel Scale

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Quiet Pavement

The Decibel Scale

Increasing the decibel level by10 doubles the noise intensity!

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Quiet Pavement

The Decibel Scale

A reduction of 3 dB(A) is like doubling the distance from the noise.

67 dB(A)

50 ft

Quiet Pavement

The Decibel Scale

A reduction of 3 dB(A) is like doubling the distance from the noise.

67 dB(A)

100 ft

- 3 dB(A) = 64 dB(A)

Quiet Pavement

Noise Makes News!

• Road Surface Material Can Reduce Noise– “Bituminous surfaces generally produce less noise than do

concrete surfaces . . .” Star-Tribune, Minneapolis, MN, March 21, 1999, pg. 6E.

• Drivers on Exeter, U.K.’s A30 Complain About Noise from Concrete Surface, Joining Residents for Asphalt Resurfacing– Western Morning News, Exeter, U.K., December 4, 1999

Quiet Pavement

Noise Makes News!• Residents Living Near New York City’s Long Island

Expressway are Upset at Noise from New Concrete Roadbed– Daily News, Donald Bertrand, New York City, Sept. 20, 1999,

Suburban, pg. 1

• Livonia Residents Complain of Freeway Noise– “Hundreds of people who live along I-275 . . . have complained about

increased noise . . . since the state re-paved the road with concrete.” The Detroit News, Sheri Hall, Livonia, MI, November 3, 2000, http://detnews.com/wayne/0011/03/

Quiet Pavement

Noise Makes News!

• What can be done?– Erect Noise Walls– Plant Trees/Shrubs– Surface Pavement with Hot Mix Asphalt

• Open-Graded Friction Course• Stone Matrix Asphalt• Dense-Graded HMA

Quiet Pavement

Noise WallsEffective only for those not in line-of-sight.

Do not reduce noise atsource.

Quiet Pavement

• Effectiveness must justify expense.

• Cases:– I-40, Knoxville: >$25,000/home– I-285, Atlanta: Requirements of > 69 dB(A)

and < $50,000/home– U.S. 441, West Boca, FL: > 67dB(A),

<$30,000/home, reduction of > 5dB(A)

Noise Walls

Quiet Pavement

• Noise factors including vehicle type, speed, and tire tread are beyond control of agency.

• A recent survey shows (NCHRP Synthesis 286) pavement texture is most important factor in highway noise.

• Pavement texture can be controlled.

What Can Be Done?

Quiet Pavement

• DOTs indicate a strong need for pavement noise control strategies.

• Proper selection of pavement surface is the best method to reduce noise from pavement/tire interactions.

What Can Be Done?

Quiet Pavement

Noise Generators

• Major noise generators of vehicles are:– engine,– exhaust system,– aerodynamic noise, and – tire noise.(Herman, TRR 1626; McNerney, et al., TRR 1626)

• For > 50 mph, pavement/tire noise dominates.(Billera, et al., TRR 1601)

Quiet Pavement

Effect of Pavement Surface

• Swedish study - pavement surface can cause a change of up to 15 dB(A). (Sandberg, Inter-Noise 79, 1979)

• Noise studies in U.S. and Europe show asphalt surfaces quieter than PCC. (Wayson, NCHRP Synthesis 268)

Quiet Pavement

• Open-graded asphalt surfaces are up to 10 dB(A) quieter than transversely tined PCC pavements. (Hibbs and Larson, FHWA-SA-96-068, 1996; Jofre, et al., 7th Int’l Symposium on Conc. Roads, 1994; Younger, et al., FHWA-OR-RD-95-13B, 1994)

• A decrease of 3 dB(A) is significant. Has the same effect as doubling distance.

Effect of Pavement Surface

Quiet Pavement

• OGFC is the quietest surface type. (Wayson, NCHRP Synthesis 268)

• SMA has also proven to be a quiet surface. (Wisconsin DOT, 1993)

• Dense graded HMA surfaces are quieter than PCC pavements.(Hibbs and Larson, Report FHWA-SA-96-068, May 1996)

Effect of Pavement Surface

Quiet Pavement

Summary

• Highway noise is important to the public.

• Small changes in dB level are noticeable.– Increase of 10 dB(A) doubles noise– Decrease of 3 dB(A) is like doubling

distance

Quiet Pavement

Summary

• Noise walls can work, but:– They are expensive.– They don’t work in all types of terrain.– Source of noise is still there.

• Asphalt pavements can reduce noise up to 10 dB(A).

Quiet Pavement

Hot Mix Asphalt

Summary• Asphalt pavements for noise reduction

in order of effectiveness:– OGFC– SMA– Dense-Graded HMA(NCHRP Synthesis 268)

PCC