Update on Results of Long- term Traffic Noise Measurements for Pavement Overlay Projects James A. Reyff Illingworth & Rodkin, Inc Summer Meeting TRB ACD40 Williamsburg, VA

Study Results Summarized I-80 Davis OGAC – 8 years State Route 138, Los Angeles County – 3+ years ADOT Pilot Studies – 2+ years

I-80 Pavement Project Location: I-80 just east of Davis and west of Sacramento, CA Traffic: ,000 ADT (almost 10% trucks) ,000 ADT Existing - Aged AC surfacing DGAC (60mm) applied in June 1998 OGAC (25 mm) applied in July 1998

I-80 Environment

Existing AC Pavement

6 Year Old OGAC

I-80 Davis 8yr Findings

I-80 Davis 7yr Findings Seasonal Effect

I-80 Davis 8yr Findings Calculated Reduction from Baseline

I-80 Davis 8yr Findings Tire/Pavement Sound Intensity

Frequency Spectra – 20m 7 Year Baseline

Frequency Spectra – 145m 8 Year Baseline DOWNWIND UPWIND 8 Year Baseline

LA 138 Pavement Research Research Site est Two Measurement Techniques –Statistical Passby –Onboard Tire/Pavement Sound Intensity 5 Pavements types –DGAC –Thick OGAC (75mm) –Thin OGAC (30mm) –RAC –BWC

LA 138 Results Initial results documented by Volpe and Caltrans (Illingworth & Rodkin) Initial levels up to 4 dBA lower than DGAC with Thick OGAC and RAC quietest Regular testing of Tire/pavement sound intensity – spring and fall

LA 138 Results

SI Level – Eastbound SR 138

Results of the Arizona Quiet Pavement Program – Sites 3D and 3E

Site 3D – AZ Route 202 Random Transverse Tined PCC ARFC

250ft x 5ft 50ft x 12ft & 5ft 100ft x 5ft Site 3D Measurements

Site 3D Results – Leq

3D Results – Normalized for Traffic Position MeasuredModeled Change PrePostPrePost 50 ft/12ft ft / 5ft ft / 5ft ft / 5ft

3D Results – Leq Data

Site 3E – AZ Route 101 Uniform Transverse Tined PCC ARFC

Site 3E – Measurements 100ft x 5ft 50ft x 12ft & 5ft 100ft x 5ft

Site 3E Results – Leq

3E Results – Normalized for Traffic Position MeasuredModeled Change PrePostPrePost 50 ft/12ft ft / 5ft ft / 5ft

3E Results – Leq Data

Sound Level vs. Distance Measured PCC and ARFC

Sound Level vs. Distance Measured and Modeled

250ft x 5ft 50ft x 12ft & 5ft 100ft x 5ft Site 3D Measurements

Equivalent Noise Barrier Performance Site at 100 ft Measured Noise Reduction Noise Barrier Height Site 3D10 dBA3.6m (12 ft) Site 3E9 dBA3.0m (10 ft)

I-280 San Mateo Existing PCC surface PCC and Rubberized Open Grade Onboard Tire/Pavement Sound Intensity

Initial Results for I-280

Results for I-280 after 3 yrs RAC (O)