iii





Improving FHWA’s Ability to Assess
Highway Infrastructure Health
Pilot Study Report
Notice
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the interest of information exchange. The U.S. Government assumes no liability for the use of the
information contained in this document.
The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers'
names appear in this report only because they are considered essential to the objective of the
document.

Quality Assurance Statement
The Federal Highway Administration (FHWA) provides high-quality information to serve
Government, industry, and the public in a manner that promotes public understanding. Standards and
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ensure continuous quality improvement.





















Cover Image Sources: Top Left – Pavement: ComStock, Inc./License agreement.
Top Right – Bridge: Cambridge Systematics, Inc.
Bottom Left – Bridge: Cambridge Systematics, Inc.
Bottom Right – Snowy Road: ComStock, Inc./License agreement.

Technical Report Documentation Page
1. Report No.
FHWA-HIF-12-049
2. Government Accession No.

3. Recipient’s Catalog No.

4. Title and Subtitle
Improving FHWA’s Ability to Assess
Highway Infrastructure Health
Pilot Study Report
5. Report Date
July 1, 2012
6. Performing Organization Code

7. Author(s)
Joseph Guerre, Jonathan Groeger, Sam Van Hecke, Amy
Simpson, Gonzalo Rada, Beth Visintine
8. Performing Organization Report No.

9. Performing Organization Name and Address
AMEC Environment & Infrastructure, Inc.
12000 Indian Creek Court, Suite F
Beltsville, MD 20705-1242

Cambridge Systematics, Inc.
100 CambridgePark Drive, Suite 400
Cambridge, MA 02140
10. Work Unit No. (TRAIS)

11. Contract or Grant No.
DTFH61-07-D-00030-T10002
12. Sponsoring Agency Name and Address
U.S. Department of Transportation
Federal Highway Administration
Office of Asset Management
1200 New Jersey Avenue, SE
Washington DC 20590
13. Type of Report and Period Covered
Final Report
14. Sponsoring Agency Code

15. Supplementary Notes
Ms. Nastaran Saadatmand, P.E., Task Monitor
16. Abstract
This report documents the results of a pilot study conducted as part of a project on improving FHWA’s
ability to assess highway infrastructure health. As part of the pilot study, a section of Interstate 90
through South Dakota, Minnesota, and Wisconsin was evaluated in order to 1) test approaches for
categorizing bridge and pavement condition as good/fair/poor that potentially could be used across the
country, and 2) provide a proof of concept for a methodology to assess and communicate the overall
health of a corridor with respect to bridges and pavements. As a result of the pilot study, it was found
that a bridge good/fair/poor methodology can be implemented nationwide today. For pavements, the
International Roughness Index can be used today to classify pavement ride quality nationwide. However,
additional investigation of other pavement condition metrics is necessary prior to implementation of a
holistic pavement indicator that includes distress and structural condition. Also, a conceptual condition
and health reporting tool was developed and is presented in the report.

17. Key Words
Performance management, performance measures,
pavement, bridges, Interstate Highway System,
pavement condition, pavement health, bridge condition,
bridge health, asset management
18. Distribution Statement
No restrictions.

19. Security Classif. (of this report)
Unclassified
20. Security Classif. (of this page)
Unclassified
21. No. of Pages
104
22. Price



Form DOT F 1700.7 (8-72) Reproduction of completed page authorized



SI* (MODERN METRIC) CONVERSION FACTORS
APPROXIMATE CONVERSIONS TO SI UNITS
Symbol When You Know Multiply By To Find Symbol
LENGTH
in inches 25.4 millimeters mm
ft feet 0.305 meters m
yd yards 0.914 meters m
mi miles 1.61 kilometers km
AREA
in2 square inches 645.2 square millimeters mm2
ft2 square feet 0.093 square meters m2
yd2 square yard 0.836 square meters m2
ac acres 0.405 hectares ha
mi2 square miles 2.59 square kilometers km2
VOLUME
fl oz fluid ounces 29.57 milliliters mL
gal gallons 3.785 liters L
ft3 cubic feet 0.028 cubic meters m3
yd3 cubic yards 0.765 cubic meters m3
NOTE: volumes greater than 1000 L shall be shown in m3
MASS
oz ounces 28.35 grams g
lb pounds 0.454 kilograms kg
T short tons (2000 lb) 0.907 megagrams (or "metric ton") Mg (or "t")
TEMPERATURE (exact degrees)
oF Fahrenheit 5 (F-32)/9 Celsius oC
or (F-32)/1.8
ILLUMINATION
fc foot-candles 10.76 lux lx
fl foot-Lamberts 3.426 candela/m2 cd/m2
FORCE and PRESSURE or STRESS
lbf poundforce 4.45 newtons N
lbf/in2 poundforce per square inch 6.89 kilopascals kPa
APPROXIMATE CONVERSIONS FROM SI UNITS
Symbol When You Know Multiply By To Find Symbol
LENGTH
mm millimeters 0.039 inches in
m meters 3.28 feet ft
m meters 1.09 yards yd
km kilometers 0.621 miles mi
AREA
mm2 square millimeters 0.0016 square inches in2
m2 square meters 10.764 square feet ft2
m2 square meters 1.195 square yards yd2
ha hectares 2.47 acres ac
km2 square kilometers 0.386 square miles mi2
VOLUME
mL milliliters 0.034 fluid ounces fl oz
L liters 0.264 gallons gal
m3 cubic meters 35.314 cubic feet ft3
m3 cubic meters 1.307 cubic yards yd3
MASS
g grams 0.035 ounces oz
kg kilograms 2.202 pounds lb
Mg (or "t") megagrams (or "metric ton") 1.103 short tons (2000 lb) T
TEMPERATURE (exact degrees)
oC Celsius 1.8C+32 Fahrenheit oF
ILLUMINATION
lx lux 0.0929 foot-candles fc
cd/m2 candela/m2 0.2919 foot-Lamberts fl
FORCE and PRESSURE or STRESS
N newtons 0.225 poundforce lbf
kPa kilopascals 0.145 poundforce per square inch lbf/in2
*SI is the symbol for th International System of Units. Appropriate rounding should be made to comply with Section 4 of ASTM E380. e
(Revised March 2003)
Improving FHWA's Ability to Assess Highway Infrastructure Health
Pilot Study Report i

Table of Contents
List of Acronyms ............................................................................................................ vi
Executive Summary .................................................................................................. ES-1
Defining Good/Fair/Poor ............................................................................... ES-1
Pilot Study .......................................................................................................... ES-2
Health Report .................................................................................................... ES-2
Findings and Recommendations .................................................................... ES-3
1.0 Study Overview .................................................................................................. 1-1
1.1 Introduction ................................................................................................. 1-1
1.2 Study Objectives ......................................................................................... 1-3
1.3 Study Milestones ......................................................................................... 1-3
1.4 Structure of this Report .............................................................................. 1-6
2.0 Defining Good/Fair/Poor ................................................................................... 2-1
2.1 Good/Fair/Poor Definitions ..................................................................... 2-1
2.2 Options for Good/Fair/Poor Metrics ...................................................... 2-2
2.3 Bridge Good/Fair/Poor Options ............................................................. 2-3
2.4 Pavement Good/Fair/Poor Options ..................................................... 2-13
3.0 Pilot Study Data Collection .............................................................................. 3-1
3.1 Pilot corridor selection ............................................................................... 3-1
3.2 Corridor Overview ..................................................................................... 3-2
3.3 Bridge Data Collection ............................................................................... 3-2
3.4 Pavement Data Collection ......................................................................... 3-2
4.0 Pilot Study Bridge Results ................................................................................ 4-1
4.1 Data Findings .............................................................................................. 4-2
4.2 Condition Assessment Findings ............................................................... 4-2
4.3 Conclusions ................................................................................................. 4-7
5.0 Pilot Study Pavement Results .......................................................................... 5-1
5.1 Data Findings .............................................................................................. 5-2
5.2 Condition Assessment Findings ............................................................. 5-10
5.3 Conclusions and Recommendations ...................................................... 5-21
Table of Contents, continued
ii Pilot Study Report

6.0 Health Assessment and Reporting .................................................................. 6-1
6.1 Vision for Health Reporting ...................................................................... 6-1
6.2 Health Report Sample ................................................................................ 6-2
6.3 Defining Green/Yellow/Red .................................................................... 6-7
6.4 Health Report Organization ...................................................................... 6-8
6.5 Implementation Considerations ............................................................. 6-19
7.0 Summary of Key Findings and Recommendations...................................... 7-1
7.1 Good/Fair/Poor Process ........................................................................... 7-1
7.2 Data Collection Improvement Opportunities ......................................... 7-2
7.3 Health Reporting ........................................................................................ 7-3
7.4 Recommended Next Steps ......................................................................... 7-3
Improving FHWA's Ability to Assess Highway Infrastructure Health
Pilot Study Report iii
List of Tables
Table E.1 Performance Measurement Options for Good/Fair/Poor
Addressed During this Study .............................................................. ES-2
Table 2.1 Defining Good/Fair/Poor ...................................................................... 2-2
Table 2.2 Performance Measurement Options for Good/Fair/Poor
Addressed During this Study ................................................................. 2-3
Table 2.3 Bridge Option 3 – Weights Assigned to the NBI Condition
Ratings ....................................................................................................... 2-4
Table 2.4 NBIAS Health Index Weight Factors..................................................... 2-8
Table 2.5 Option 3.a Weights ................................................................................ 2-10
Table 2.6 Components of Sufficiency Rating Calculation ................................. 2-11
Table 2.7 Option 3.b Weights ................................................................................ 2-11
Table 2.8 IRI G/F/P Thresholds ........................................................................... 2-15
Table 2.9 PCI Thresholds ....................................................................................... 2-15
Table 2.10 PCI G/F/P Thresholds Used for this Study ....................................... 2-16
Table 2.11 FCI G/F/P Thresholds .......................................................................... 2-17
Table 2.12 Deflection G/F/P Thresholds .............................................................. 2-17
Table 2.13 RSL Terminal Distress Values .............................................................. 2-19
Table 2.14 RSL G/F/P Thresholds ......................................................................... 2-19
Table 3.1 Temporal Consistency of Initial Gathered/Collected Pavement
Data ............................................................................................................ 3-7
Table 4.1 Pilot Corridor Bridges and Culverts ..................................................... 4-1
Table 4.2 Option 3 Weights ..................................................................................... 4-1
Table 4.3 Correlation of Options for Bridges in the Pilot Corridor ................... 4-3
Table 4.4 Correlation of Options for Interstate Bridges in the 48
Contiguous States..................................................................................... 4-4
Table 5.1 Correlation of IRI Between Data Sets .................................................... 5-4
Table 5.2 Correlation between HPMS and Field Cracking Data ........................ 5-7
Table 5.3 Correlations between Rutting Data Sets ............................................... 5-8
Table 5.4 Good/Fair/Poor Based on PCI Field Data ......................................... 5-12
Improving FHWA's Ability to Assess Highway Infrastructure Health
iv Pilot Study Report
Table 5.5 FCI Thresholds ....................................................................................... 5-14
Table 5.6 Good/Fair/Poor Based on RWD Field Data ...................................... 5-16
Table 5.7 Confidence Levels for Pavement Condition Measures
Evaluated ................................................................................................. 5-21
Table 6.1 Pavement Condition History Matrix ................................................... 6-11
Table 6.2 Pavement Comparison to National Average Matrix ........................ 6-13
Table 6.3 Bridge Condition History Matrix ......................................................... 6-15
Table 6.4 Bridge Comparison to National Average Matrix .............................. 6-16

List of Figures
Figure 1.1 Project Milestones .................................................................................... 1-4
Figure 3.1 I-90 Pilot Corridor .................................................................................... 3-1
Figure 3.2 Automated Multi-Function Vehicle Used for Pavement
Condition Evaluation .............................................................................. 3-5
Figure 3.3 Rolling Wheel Deflectometer Used for Structural Evaluation........... 3-6
Figure 4.1 Results of Bridge Options 2 & 3 for Pilot Corridor ............................. 4-2
Figure 4.2 Results for Interstate Bridges in the 48 Contiguous States ................. 4-4
Figure 4.3 Distribution of Condition Ratings for Interstate Bridges in the
48 Contiguous States ................................................................................ 4-5
Figure 4.4 Weighted Average of Condition Ratings for Option 3.a for
Interstate Bridges in the 48 Contiguous States..................................... 4-6
Figure 4.5 Comparison of Average Rating and Variance for Interstate
Bridges in the 48 Contiguous States ...................................................... 4-7
Figure 5.1 Distribution of Pilot Study Pavements by Type .................................. 5-1
Figure 5.2 Comparison of HPMS, State, and Field IRI on Asphalt-Surfaced
Pavements ................................................................................................. 5-2
Figure 5.3 Comparison of HPMS, State and Field IRI on PCC-Surfaced
Pavements ................................................................................................. 5-3
Figure 5.4 Comparison of Percent Cracking on Asphalt-Surfaced
Pavements ................................................................................................. 5-5
Figure 5.5 Comparison of Cracking Length on Asphalt-Surfaced
Pavements ................................................................................................. 5-6