Acoustic Perception in Pavement Rating

Bernard Izevbekhai, P.E.Research Operations EngineerMnDOT Office of Materials &

Roads Research

OBJECTIVES• Demystify Acoustic Version of this Puzzle

• Ascertain if Acoustic Perception explained residuals or anomalies in 2010 Pavement Rating

RAISON D’ETRE

We are Subject to the whims of Frequency Domains irrespective Domain (Tactile, Spatial, Time) of Interest

RAISON D’ETRE

Phycoacoustics have always with us.

Some Important Reasons why people ask for noise walls:

•We cannot be Left out.

• We do not want to see the vehicles ( Out of sight is out of Hearing)

•We are tax payers

TIRE PAVEMENT NOISE FUNDAMENTALS

NOISE

Pavement Smoothness IRI (Mega texture)

TEXTURE PAVEMENT SMOOTHNESS AND TIRE PAVEMENT INTERACTION NOISE (TPIN) ARE FUNDAMENTAL TO TIRE PAVEMENT INTERACTION

Macrotexture

DirectionOrientation (Spikiness)Asperity IntervalMicrotexture

LAYOUT OF 31 CONTIGUOUS TEST SECTIONS

Note The order For Later Discussion

ESTABLISHED PHENOMENOLOGICAL MODEL

FORM OF PROPOSED MODEL

OBSI=A+B*((293-T)/T)+ C*(IRI/IRIT)+ [(ASPT/ASP)*(D*DIR

+E)]+ F*(SP)

PROPOSED MODEL OBSI =

99.023+20.164((293-T)/T)+[(ASPT/ASP)(1.513 DIR+0.098)]+

5.849(IRI/IRIT)+1.684 SP Significant Variables P-value needs to be < 0.05. It is noted that p-values for the variables in model are in the range 0<=p<0.0002

Izevbekhai, Khazanovich and Voller (2011)

STRATEGY• 44 Volunteers Equitable Gender and Age

Distribution• No State Employee, No Pavement expert• 2010 Chevrolet Malibu New• Many Runs Rating from 0-10 (Scaled 0-5)• DIV Measured IRI behind the Rating Panels• Preliminary Analysis Reveals anomaly in

IRI MPR Correlation

Section ID

User Rating

Mean MPR

Pavt Type

Mean IRI Mean

RN

Mean 1997 MPR

OBSI Mean

(Runs 1 & 2)

OBSI Mean Run 3

Test Speed

for Run 3 (mph)

1 6.7 3.4 BIT 62.15 3.87 3.6 102.9 102.1 55 2 8.5 4.3 BIT 44.03 4.34 3.9 102.3 101.6 55 3 7.8 3.9 CON 44.07 4.10 4.3 103.3 103.2 60 4 8 4.0 BIT 57.73 4.12 3.7 103.9 104.1 60 5 8.1 4.1 CON 31.60 4.45 4.7 103.7 103.9 60 6 7 3.5 BIT 158.89 3.31 2.4 103.7 96.0 35 7 4.7 2.4 BIT 145.26 2.28 2.5 102.8 97.2 45 8 4.3 2.2 BIT 196.30 1.54 2.0 106.4 105.4 55 9 5.2 2.6 BIT 164.60 1.98 2.3 106.0 105.2 55

10 6 3.0 BIT 108.34 2.35 2.9 105.8 105.2 55 11 6.1 3.1 BIT 118.41 2.69 2.8 105.6 105.2 55 12 5.2 2.6 BIT 147.25 2.15 2.5 105.4 105.4 55 13 4.9 2.5 BIT 155.88 2.15 2.4 106.0 105.0 55 14 5.6 2.8 BIT 130.07 2.36 2.7 105.9 104.9 55 15 7.8 3.9 BIT 65.40 3.98 3.6 102.1 101.3 55 16 7.7 3.9 BIT 63.64 4.14 3.6 103.1 102.6 55 17 6.4 3.2 BIT 87.33 3.40 3.2 103.7 103.3 55 18 6.7 3.4 BIT 82.00 3.42 3.3 103.2 103.0 55 19 5.8 2.9 BIT 91.08 1.96 3.2 103.9 103.8 55 20 7.2 3.6 CON 52.19 3.53 4.1 104.9 106.4 65 21 7.3 3.7 CON 51.73 3.84 4.1 105.0 106.6 65 22 6 3.0 CON 60.62 3.35 3.9 105.6 106.7 65 23 6.5 3.3 CON 60.10 3.67 3.9 105.6 106.9 65 24 6.6 3.3 CON 61.79 3.61 3.9 106.0 106.9 65 25 6.2 3.1 CON 62.32 3.72 3.9 105.9 107.1 65 26 5.9 3.0 CON 62.98 3.63 3.8 105.9 107.1 65 27 6 3.0 CON 69.24 3.38 3.7 105.7 106.8 65 28 6.6 3.3 CON 103.30 3.40 3.0 108.6 110.1 65 29 6.8 3.4 BIT 70.30 3.57 3.5 104.4 103.3 55 30 4.2 2.1 CON 170.51 2.53 2.0 107.4 98.5 30* 31 5.2 2.6 CON 146.66 2.86 2.3 107.2 101.1 30*

RESULTS FROM 31 CONTIGUOUS TEST SECTIONS

RATING PANEL

OBSIIRI

MPR IRI/ RN

ANALYTICAL PATH

On Board Sound Intensity SI level (dB(A))= 10 * log10 ∑ 10 {SI

1/SI

o} )

Where SIi (i=1, 2 , 3, …, 12) are sound intensities in dB at each the 3rd octave frequencies.

SI0 = SI at threshold of human hearing = 10-12 Watts/m2

Measurement of Tire Pavement Noise

Compare to Izevbekhai et al (2011) There may be influential data (AKA outliers

MPR Vs OBSI

OBSI VS RESIDUALS

NO CORRELATION WITH RESIDUALS

Investigate Sequencing

Investigate Sequencing

Anomalies in Sections 6 and 28 Accentuated

DUE DILIGENCE: What of RN?

Anomalies in Sections 6 and 28 Accentuated

DUE DILIGENCE: RN

Conclusion and Recommendation

• This study examined MPR, IRI, and OBSI of 31contiguous sections

• to ascertain the possibility of pavement noise influencing anomalous rating.

• Based on the analysis conducted, no tenable statistically significant evidence that OBSI explains anomalies in MPR.

• Sequencing may have affected some ratings

Conclusion and Recommendation

• Reversed Runs recommended with raters Hood winked (Complete Lane Closure)

• Populate a data base of MPR and OBSI.• No individual study is all encompssing.

Continuing studies Recommended.• Results do not negate the likelihood of

Noise influencing rating in a larger population but in this study it was not significant.

QUESTIONS

I THAN

K THEE