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SPR-555: Atmospheric Effects Associated with Highway Noise Propagation

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SPR-555: Atmospheric Effects Associated with Highway Noise Propagation ATMOSPHERIC EFFECTS ASSOCIATED WITH HIGHWAY NOISE PROPAGATION Final Report 555 Prepared By: Hugh Saurenman, ATS Consulting, LLC Jim Chambers, National Center for Physical Acoustics, The University of Mississippi Louis C. Sutherland, Consultant in Acoustics Robert L. Bronsdon, Consultant in Acoustics Hans Forschner, Navcon Engineering Network October 2005 Prepared for: Arizona Department of Transportation 206 South 17th Avenue Phoenix, Arizona 85007 in cooperation with U.S. Department of Transportation Federal Highway Administration The contents of the report reflect the views of the authors who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the Arizona Department of Transportation or the Federal Highway Administration. This report does not constitute a standard, specification, or regulation. Trade or manufacturers’ names that may appear herein are cited only because they are considered essential to the objectives of the report. The U.S. government and The State of Arizona do not endorse products or manufacturers. Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. FHWA-AZ-05-555 4. Title and Subtitle 5. Report Date October 2005 Atmospheric Effects Associated with Highway Noise Propagation 6. Performing Organization Code 7. Author 8. Performing Organization Report No. Hugh Saurenman, Jim Chambers, Louis C. Sutherland, Robert L. Bronsdon, Hans Forschner 9. Performing Organization Name and Address 10. Work Unit No. ATS Consulting, LLC 11. Contract or Grant No. 725 S. Figueroa Street, Suite 1580 T04-58-A0001 Los Angeles, CA 90017 12. Sponsoring Agency Name and Address 13.Type of Report & Period Covered ARIZONA DEPARTMENT OF TRANSPORTATION Final Report 206 S. 17TH AVENUE September 2003, August 2005 PHOENIX, ARIZONA 85007 14. Sponsoring Agency Code ADOT Project Manager: Estomih Kombe 15. Supplementary Notes Prepared in cooperation with the U.S. Department of Transportation, Federal Highway Administration 16. Abstract The primary questions investigated in this project were: What are the atmospheric conditions in the Phoenix valley that contribute to higher than normal sound levels? Are the conditions unique to the Phoenix valley? Can the atmospheric effects be anticipated? The main components of the project were: (1) a review of literature relevant to sound propagation, (2) detailed noise measurements in a Scottsdale neighborhood along the East Loop 101 Freeway, (3) computer modeling of sound propagation under various measured and inferred atmospheric conditions, (4) noise measurements before and after installation of an asphalt rubber friction course (ARFC) on the Pima Freeway by the ADOT Quiet Pavement Pilot Program, and (5) a pilot study investigating parametric models of tire/pavement noise. Some key conclusions are: nighttime thermal inversion conditions that are common in the Phoenix valley from October through March cause sound level increases of 5 to 8 dB at distances greater than 1/4 mile from freeways, nighttime down-slope drainage flows off the mountain ranges surrounding the Phoenix valley cause localized focusing and de-focusing of sound levels, sound level variations under inversion conditions appear to be greatest at locations that are upwind relative to the down-slope flows, the highest sound levels during the October to March period will usually occur right around sunrise when high traffic volumes coincide with strong inversion conditions, and installation of the ARFC reduces sound levels by 8 to 10 dBA both close to the roadway and at distances of 1/4 mile and greater. A final tentative conclusion is that, based on the computer modeling, there may be a rapid onset of refraction effects between about 200 and 300 m (650 to 1000 ft) from Phoenix valley roadways, 17. Key Words 18. Distribution Statement 23. Registrant's Seal Acoustics, sound propagation, highway noise, Document is available to the atmospheric effects, quiet pavement, U.S. public through the National Technical Information Service, Springfield, Virginia 22161 19. Security Classification 20. Security Classification 21. No. of Pages 22. Price Unclassified Unclassified 174 SI* (MODERN METRIC) CONVERSION FACTORS APPROXIMATE CONVERSIONS TO SI UNITS APPROXIMATE CONVERSIONS FROM SI UNITS Symbol When You Know Multiply By To Find Symbol Symbol When You Know Multiply By To Find Symbol LENGTH LENGTH in inches 25.4 millimeters mm mm millimeters 0.039 inches in ft feet 0.305 meters m m meters 3.28 feet ft yd yards 0.914 meters m m meters 1.09 yards yd mi miles 1.61 kilometers km km kilometers 0.621 miles mi AREA AREA 2 2 2 2 in square inches 645.2 square millimeters mm mm Square millimeters 0.0016 square inches in 2 2 2 2 ft square feet 0.093 square meters m m Square meters 10.764 square feet ft 2 2 2 2 yd square yards 0.836 square meters m m Square meters 1.195 square yards yd ac acres 0.405 hectares ha ha hectares 2.47 acres ac 2 2 2 2 mi square miles 2.59 square kilometers km km Square kilometers 0.386 square miles mi VOLUME VOLUME fl oz fluid ounces 29.57 milliliters mL mL milliliters 0.034 fluid ounces fl oz gal gallons 3.785 liters L L liters 0.264 gallons gal 3 3 3 3 ft cubic feet 0.028 cubic meters m m Cubic meters 35.315 cubic feet ft 3 3 3 3 yd cubic yards 0.765 cubic meters m m Cubic meters 1.308 cubic yards yd NOTE: Volumes greater than 1000L shall be shown in m3. MASS MASS oz ounces 28.35 grams g g grams 0.035 ounces oz lb pounds 0.454 kilograms kg kg kilograms 2.205 pounds lb T short tons (2000lb) 0.907 megagrams mg Mg megagrams 1.102 short tons (2000lb) T (or “metric ton”) (or “t”) (or “metric ton”) TEMPERATURE (exact) TEMPERATURE (exact) ºF Fahrenheit 5(F-32)/9 Celsius temperature ºC ºC Celsius temperature 1.8C + 32 Fahrenheit ºF temperature or (F-32)/1.8 temperature ILLUMINATION ILLUMINATION fc foot candles 10.76 lux lx lx lux 0.0929 foot-candles fc fl foot-Lamberts 3.426 candela/m2 cd/m2 cd/m2 candela/m2 0.2919 foot-Lamberts fl FORCE AND PRESSURE OR STRESS FORCE AND PRESSURE OR STRESS lbf poundforce 4.45 newtons N N newtons 0.225 poundforce lbf lbf/in2 poundforce per 6.89 kilopascals kPa kPa kilopascals 0.145 poundforce per lbf/in2 square inch square inch Table of Contents Executive Summary .........................................................................................................................1 Background ..............................................................................................................................1 Atmospheric Parameters ..........................................................................................................1 Conditions in the Phoenix Valley ............................................................................................2 Diurnal Sound Level Patterns in the Phoenix Valley...............................................................4 Study Conclusions....................................................................................................................6 1. Introduction..............................................................................................................................9 1.1 Basic Acoustical Concepts ..........................................................................................10 1.2 Bending of Sound Waves by Diffraction and Refraction ............................................13 2. Background on Sound Propagation........................................................................................15 2.1 Neutral Atmospheric Conditions .................................................................................15 2.1.1 Geometric Spreading ......................................................................................15 2.1.2 Atmospheric Absorption.................................................................................16 2.1.3 Ground Effects................................................................................................18 2.1.4 Diffraction by Barriers and Other Obstructions .............................................19 2.2 Atmospheric Effects ....................................................................................................20 2.2.1 Refraction .......................................................................................................20 2.2.2 Turbulence......................................................................................................22 2.2.3 Computer Modeling of Refraction Effects .....................................................23 3. Conditions in the Phoenix Valley ..........................................................................................29 3.1 General Meteorological Conditions.............................................................................29 3.2 Wind Speed and Direction...........................................................................................31 4. Noise Measurements..............................................................................................................35 4.1 Measurement Locations and Procedures .....................................................................35 4.1.1 Measurement Sites..........................................................................................35 4.1.2 Measurement Equipment and Procedures ......................................................39 4.2 Analysis of A-Weighted Measurement .......................................................................40 4.2.1 Noise
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