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Publication Number: FHWA-HRT-06-066
Date: March 2006

Long-Term Pavement Performance Inventory Data Collection Guide

Appendix A. Standard Codes

Many different types of data are collected on test sections studies as part of the Long-Term Pavement Performance (LTPP) program. This document provides the guidelines necessary for collecting inventory data on these sections. Inventory data include those necessary to: 1) identify the test section, 2) describe the geometric details of its construction and the material properties of its structural constituents, and 3) identify construction costs and costs of subsequent maintenance and repair before the long-term monitoring (LTM) effort. Table 1 provides a general list of inventory data elements.

All of these data, with the exception of certain material properties such as subgrade strength and moisture content that change over time or environment, should remain constant throughout the monitoring period of each test section or project unless the pavement is resurfaced or rehabilitated during the period. In either case, the test section becomes for practical purposes a new pavement structure with new surface conditions, so the basic inventory data must be revised to describe these new conditions, while the original data is retained for reference in long-term cost analyses and studies of the effects of rehabilitation on deterioration rates. The additional rehabilitation data elements recommended for collection in the event this occurs during the monitoring period are discussed in the Maintenance and Rehabilitation Data Collection Guide.

This document provides data sheets and instructions to collect inventory data for the LTPP program. The inventory data sheets appear in numerical sequence at the end of this document.

The inventory data sheets have been taken from the original Long-Term Monitoring Data Collection Guide and modified to reflect evolution in planning for LTM of pavements. This was done partially to maintain some consistency with the LTM pilot study databases, but primarily to take advantage of the work already accomplished for the Federal Highway Administration (FHWA) during the LTM studies, and during studies for the National Cooperative Highway Research Program (NCHRP) Project 1-19.

The data sheets allow collection of detailed information on the variability of materials and layer thicknesses, because this variability is known to contribute heavily to pavement deterioration. Replicate test data is often unavailable, so single test results in these cases should be entered as the mean and other values left blank. However, whenever possible, data on variability should be obtained.

Data collected for a General Pavement Studies (GPS) test section should pertain to the original construction of the section or the most recent rehabilitation/reconstruction. The data sheets required for each GPS test section will depend on the type of materials contained in the structure of that test section. Sheets 1, 2, 3, and 4 are required for every GPS test section. Sheet 3 indicates the numbers of the additional required data sheets for each material type present in the pavement structure. Sheet 1A is required for every GPS test section where measurements are made with a global positioning system receiver.

 

Table 1. Items of Inventory Data To Be Collected
1. Test Section Identification

Route Number
State, County, and District
Lane Monitored
Experiment Code

Functional Class
Location of Test Section
Direction of Travel

2. Geometric Details and General Information

Number of Lanes
Lane Width
Type of Pavement
Type of Subsurface Drainage
Location of Subsurface Drains
Identification of Layer Materials
Thickness of Layers
Depth to Rigid Layer
Year Widened
Identification of Materials Used in Overlay or Reconstruction
Dowel Bar Diameter, Length, and Installation Method

Shoulder Width
Shoulder Structure
Portland Cement Concrete (PCC) Shoulder Joint Information
Year Originally Constructed
Thicknesses of Overlays or Final Layer
Years when Major Improvements Occurred
Joint Spacing, Reservoir Width
Sealant Type and Forming Method
Type of Load Transfer (Aggregate Interlock or Dowels)
Tie Bar Spacing, Coating, Diameter, Length, and Spacing

3. Material Properties
a. Subgrade Soil

Soil Type and Classification
Plasticity Index
In Situ Dry Density
In Situ Moisture Content
Swell Potential
Frost Susceptibility
Resilient Modulus
Relative Density
Optimum Laboratory Moisture Content

Liquid Limit
Percent Passing No. 40 Sieve
Percent Passing No. 200 Sieve
California Bearing Ratio
R-Value
Modulus of Reaction
Maximum Laboratory Dry Density
Soil Suction
Rate of Heave

b. Base and Subbase Layers (Unbound or Stabilized)

Soil Type and Classification
Optimum Laboratory Moisture Content
Material Gradation
Percent of Stabilizing Agent
California Bearing Ratio
Resistance (R-Value)
Compressive Strength

Maximum Laboratory Dry Density
In Situ Dry Density
In Situ Moisture Content
Resilient Modulus
Type of Treatment (Cement, Lime, etc.)
Modulus of Subgrade Reaction

Asphalt Grade
Asphalt Content
Penetration of Original Asphalt
Source and Specific Gravity of Asphalt
Viscosity and Ductility of Original Asphalt
Softening Point of Asphalt
Types of Asphalt Modifiers
Original Stability
Properties of Laboratory Aged Asphalt
Type of Asphalt Plant
In-Place Mixture Properties
Type and Amount of Antistripping Additives
Compaction Data
Mixing Temperatures

Initial Air Voids
Voids in Mineral Aggregate
Types of Coarse and Fine Aggregates
Geologic Classifications of Coarse Aggregates
Polish Value of Coarse Aggregates
Gradations of Coarse and Fine Aggregates
Bulk Specific Gravities of Aggregates
Effective Specific Gravities of Aggregates
Aggregate Durability
Resilient Modulus
Tensile Strength
Creep Compliance
Moisture Susceptibility

d. Portland Cement Concrete Layers
Type, Amount, Yield Strength, and Placement of Reinforcing Steel
Mix Design Information
Coarse Aggregate Type and Gradation
Fine Aggregate Type and Gradation
Alkali Content of Cement
Entrained Air
Aggregate Durability
Method for Curing and Finishing

Modulus of Rupture
Elastic Modulus
Tensile Strength
Compressive Strength
Type of Paver
Slump
Type of Cement
Insoluble Residue
Bulk Specific Gravities

4. Historical Pavement Related Cost Data
Initial Construction Cost
Costs for Major Improvements
Maintenance Costs

Data collected for Specific Pavement Studies (SPS) experiment projects may be provided by an adjacent GPS test section. An entry must be available in the SPS_GPS_LINK table in the LTPP Information Management System (IMS) identifying the adjacent GPS test section number for the relevant project. Data for all SPS projects should pertain to the original construction before any construction related to the SPS requirements. Table 2 shows the data sheets required for each SPS experiment, by experiment number.

 

Table 2. Data Sheets Required by SPS Experiment
Inventory Data Sheets SPS Experiment Number
1 2 3A 4A 5 6 7 8 9B
1 - - X X X X X - X
1AC X X X X X X X X X
2 - - X X X X X - X
3 - - X X X X X - X
4 - - X X X X X - X
5 - - - X - X X - X
6 - - - X - X X - X
7 - - - X - X X - X
8 - - - X - X X - X
9 - - - X - X X - X
10 - - - X - X X - X
11 - - - X - X X - X
12 - - X - X - X - X
13 - - X - X - X - X
14 - - X - X - X - X
15 - - X - X - X - X
16 - - X - X - X - X
17 - - X - X - X - X
18 - - X - X - X - X
19 - - X X X X X - X
20 - - X X X X X - X
21 - - X X X X X - X
22 - - X X X X X - X
23 - - X X X X X - X

A Data for SPS-3 and SPS-4 projects may be completed for an adjacent GPS test section. An entry must be available in the SPS_GPS_LINK table identifying the adjacent GPS test section number for the relevant SPS-3 or SPS-4 project.

B Inventory sheets for SPS-9 required only for overlay of existing pavements, with the exception of data sheet 1A.

C Inventory data sheet 1A is required for every SPS project or GPS test section where measurements are made with a global positioning system.

 

Table A.1. Table of Standard Codes for States, District of Columbia, Puerto Rico, American Protectorates, and Canadian Provinces
State Code State Code
Alabama 01 North Carolina 37
Alaska 02 North Dakota 38
Arizona 04 Ohio 39
Arkansas 05 Oklahoma 40
California 06 Oregon 41
Colorado 08 Pennsylvania 42
Connecticut 09 Rhode Island 44
Delaware 10 South Carolina 45
District of Columbia 11 South Dakota 46
Florida 12 Tennessee 47
Georgia 13 Texas 48
Hawaii 15 Utah 49
Idaho 16 Vermont 50
Illinois 17 Virginia 51
Indiana 18 Washington 53
Iowa 19 West Virginia 54
Kansas 20 Wisconsin 55
Kentucky 21 Wyoming 56
Louisiana 22 American Samoa 60
Maine 23 Guam 66
Maryland 24 Puerto Rico 72
Massachusetts 25 Virgin Islands 78
Michigan 26 Alberta 81
Minnesota 27 British Columbia 82
Mississippi 28 Manitoba 83
Missouri 29 New Brunswick 84
Montana 30 Newfoundland 85
Nebraska 31 Nova Scotia 86
Nevada 32 Ontario 87
New Hampshire 33 Prince Edward Island 88
New Jersey 34 Quebec 89
New Mexico 35 Saskatchewan 90
New York 36

 

Table A.2. Functional Class Codes
Functional Class Code
Rural:
Principal Arterial—Interstate 01
Principal Arterial—Other 02
Minor Arterial 06
Major Collector 07
Minor Collector 08
Local Collector 09
Urban:
Principal Arterial—Interstate 11
Principal Arterial—Other Freeways or Expressways 12
Other Principal Arterial 14
Minor Arterial 16
Collector 17
Local 19

Experiment Type Definitions

General Pavement Studies

(01) Asphalt Concrete Pavement with Granular Base

Acceptable pavements for this study include a dense-graded HMAC surface layer, with or without other HMAC layers, placed over untreated granular base. One or more subbase layers may also be present, but are not required. A treated subgrade is classified as a subbase layer. Full depth AC pavements—defined as an HMAC surface layer combined with one or more subsurface HMAC layers beneath the surface layer with a minimum total HMAC thickness of 152 mm (6 inches) placed directly upon a treated or untreated subgrade—are also allowed in this study. Two or more consecutive lifts of the same mixture design are to be treated as one layer.

Seal coats or porous friction courses are allowed on the surface, but not in combination. For example, a porous friction course placed over a seal coat is not acceptable. Seal coats are permissible on top of granular layers. At least one layer of dense-graded HMAC is required, regardless of the existence of seal coats or porous friction courses.

(02) Asphalt Concrete Pavement with Bound Base

Acceptable pavements for this study include a dense-graded HMAC surface layer with or without other HMAC layers, placed over a bound base layer. To properly account for a variety of bound base types in the sampling design, two classifications of binder types, bituminous and nonbituminous, are defined as factor levels. Bituminous binders include asphalt cements, cutbacks, emulsions, and road tars. Nonbituminous binders include all hydraulic cements (those which harden by a chemical reaction with water and are capable of hardening under water), lime, fly ashes, and natural pozzolans, or combinations thereof. Stabilized bases with lower quality materials such as sand asphalt or soil cement are also allowed. Stabilization practices of primary concern for this study are those in which the structural characteristics of the material are improved due to the cementing action of the stabilizing agent. Thus, the description of the study actually refers to treatments improving the structural properties of the base materials. Two or more consecutive lifts of the same mixture design are to be treated as one layer. One or more subbase layers may be present but are not required.

Seal coats or porous friction courses are permitted on the surface but not in combination. For example, a porous friction course placed over a seal coat is not acceptable. Project selection is often—to those constructed on both fine and coarse subgrades.

(03) Jointed Plain Concrete Pavement—JPCP

Acceptable pavements for this study include a jointed, unreinforced PCC slab placed over an untreated granular base, HMAC, or stabilized base. One or more subbase layers may also be present, but are not required. The joints may have either no load transfer devices or smooth dowel bars. A seal coat above a granular base layer is permissible. Jointed slabs with load transfer devices other than dowel bars, and pavements placed directly upon a treated or untreated subgrade also are not acceptable.

(04) Jointed Reinforced Concrete Pavement—JRCP

Acceptable projects include jointed reinforced PCC pavements with doweled joints spaced between 66 and 213 m (20 and 65 ft). The slab may rest directly on a base layer or on unstabilized coarse-grained subgrade. A base layer and one or more subbase layers may exist, but are not required. A seal coat is also permissible over a granular base layer. JRCP placed directly over a fine-grained soil/aggregate layer or a fine-grained subgrade will not be considered for this study. JRCPs without load transfer devices or using devices other than smooth dowel bars at the joints are not acceptable.

(05) Continuously Reinforced Concrete Pavement—CRCP

Acceptable projects include continuously reinforced PCC pavements placed directly over a base layer or over unstabilized coarse-grained subgrade. One or more subbase layers can exist but are not required. A seal coat (prime coat) is permissible just above a granular base layer. The placement of CRCPs directly over a fine-grained soil/aggregate layer or a fine-grained subgrade is not acceptable for this study.

(06) AC Overlay of AC Pavement

Pavements in the GPS-6A, 6B, 6C, 6D, and 6S experiments include a dense-graded HMAC surface layer, with or without other HMAC layers, placed over an existing AC pavement.

The designation 6A refers to those sections that were overlaid before acceptance in the GPS program.

The 6B, 6C, 6D, and 6S designations refer to LTPP sections on which an overlay was placed after the section had been accepted into the LTPP program.

Seal coats or porous friction courses are allowed, but not in combination. Fabric interlayers and stress-absorbing membrane interlayers (SAMI) are permitted between the original surface and the overlay. The total thickness of HMAC used in the overlay is required to be at least 25.4 mm (1.0 inch).

(07) AC Overlay of Concrete Pavement

Pavements classified in the GPS-7A, 7B, 7C, 7D, 7F, 7R, and 7S experiments primarily consist of JPCP, JRCP, and CRCP pavements in which a dense-graded HMAC surface layer with or without other HMAC surface layers was constructed.

The exception is the 7R classification that has been added to account for PCC pavement test sections rehabilitated using Concrete Pavement Restoration (CPR) techniques. (To date, no test sections have been classified in the 7R category.)

The designation 7A refers to sections that were overlaid before acceptance in the GPS program. The 7B, 7C, 7D, 7F, and 7S designation refers to those test sections over which an overlay was placed after the section had been accepted into the LTPP program.

The PCC slab may rest upon a combination of the base and/or subbase layers. The existing concrete slab can also be placed directly over lime or cement-treated fine or coarse-grained subbase, or over untreated coarse-grained subgrade soil. Slabs placed directly over untreated fine-grained subgrade are not acceptable.

Seal coats or porous friction courses are permissible but not allowed in combination. Fabric interlayers and SAMIs are acceptable when placed between the original surface (concrete) and the overlay. Overlaid pavements involving aggregate interlayers and open-graded AC interlayers are not included in this study. The total thickness of HMAC used in the overlay is required to be at least 38 mm (1.5 inches).

(09) Unbonded JCP Overlays of Concrete Pavement

Acceptable projects for this study include unbonded JPCP, JRCP, or CRCP overlays with a thickness of 129 mm (5 inches) or more placed over an existing JPCP, JRCP, or CRCP pavement. An interlayer used to prevent bonding of the existing and the overlay slabs is required. The overlaid concrete pavement can rest on a base and/or a subbase or directly on the subgrade.

Specific Pavement Studies

(01) Structural Factors for Flexible Pavements

The experiment on Strategic Study of Structural Factors for Flexible Pavements (SPS-1) examines the performance of specific HMAC-surfaced pavement structural factors under different environmental conditions. Pavements within SPS-1 must start with either the original construction of the entire pavement structure or removal and complete reconstruction of an existing pavement. The pavement structural factors included in this experiment are in-pavement drainage layer, surface thickness, base type, and base thickness. The experiment design stipulates a traffic loading level in the study lane in excess of 100,000-80-kN (18-kip) equivalent single axle loads (ESAL) per year. The combination of the study factors in this experiment result in 24 different pavement structures. The experiment is designed using a fractional factorial approach to enhance implementation practicality; permitting the construction of 12 test sections at one site and the construction of a complementary set of 12 test sections at another site within the same climatic region on a similar subgrade type.

(02) Structural Factors for Rigid Pavements

The experiment on Strategic Study of Structural Factors for Rigid Pavements (SPS-2) examines the performance of specific JPCP structural factors under different environmental conditions. Pavements within SPS-2 must start with either the original construction of the entire pavement structure or removal and complete reconstruction of an existing pavement. The pavement structural factors included in this experiment are in-pavement drainage layer, PCC surface thickness, base type, PCC flexural strength, and lane width. The experiment requires that all test sections be constructed with perpendicular doweled joints at 4.9-m (15-ft) spacing and stipulate a traffic loading level in the lane in excess of 200,000 ESAL/year. The experiment is designed using a fractional factorial approach to enhance implementation practicality; permitting the construction of twelve test sections at one site and the construction of a complementary set of twelve test sections at another site within the same climatic region on a similar subgrade type.

(03) Preventive Maintenance Effectiveness of Flexible Pavements

The experiment on Preventive Maintenance Effectiveness of Flexible Pavements (SPS-3) examines the performance of four preventive maintenance treatments (cracking seal, chip seal, slurry seal, and thin overlay) on AC-surfaced pavement sections within the four climatic regions, on the two classes of subgrade soil. The experimental design stipulates that the effectiveness of each of the four treatments be evaluated independently. The effectiveness of combinations of treatments is not considered. Therefore, each site includes four treated test sections in addition to a control section. In most cases, the control (or "do nothing") section is classified as a GPS test section.

(04) Preventive Maintenance Effectiveness of Jointed Concrete Pavements

The experiment on Preventive Maintenance Effectiveness of Jointed Concrete Pavements (SPS-4) was designed to study the effects of crack/joint sealing and undersealing on jointed PCC pavement structures. Both JRCP and JPCP are included in the study. Undersealing is included as an optional factor and is only performed on a section for which the need for undersealing is indicated. The experiment design stipulates that the effectiveness of each of the two treatments be evaluated independently. The effectiveness of combinations of treatments is not considered. Each test site includes two treated test sections in addition to a control section. The treatment sections on joint/crack seal test sites consist of one section in which all joints have no sealant, and one in which a water tight seal is maintained on all cracks and joints.

(05) Rehabilitation of Asphalt Concrete Pavements

The experiment on Rehabilitation of Asphalt Concrete Pavements (SPS-5) examines the performance of eight combinations of AC overlays on existing AC-surfaced pavements. The rehabilitation treatment factors included in the study are intensity of surface preparation, recycled versus virgin AC overlay mixture, and overlay thickness. The experiment design includes all four climatic regions and conditions of existing pavement. The experiment design stipulates a traffic loading level in the study lane in excess of 100,000 ESALs/year.

(06) Rehabilitation of Jointed Portland Cement Concrete Pavements

The experiment on Rehabilitation of Jointed Portland Cement Concrete Pavements (SPS-6) examines the performance of seven rehabilitation treatment options as a function of climatic region, type of pavement (plain and reinforced), and condition of existing pavement. The rehabilitation methods include surface preparation (a limited preparation and full CPR) with a 102-mm (4-inch) thick AC overlay or without an overlay, crack/break and seat with two AC overlay thicknesses of 102 and 203 mm (4 and 8 inches), and limited surface preparation with a 102-mm (4-inch) thick AC overlay with sawed and sealed joints.

(07) Bonded Concrete Overlays of Concrete Pavements

The experiment on Bonded Concrete Overlays on Concrete Pavements (SPS-7) examines the performance of eight combinations of bonded PCC treatment alternatives as a function of climatic region, pavement type (jointed and continuously reinforced), and condition of existing pavement. The rehabilitation treatment factors include combinations of surface preparation methods (cold milling plus sand blasting and shot blasting), bonding agents (neat cement grout or none), and overlay thickness (76 and 127 mm (3 and 5 inches)). The experiment design stipulates a traffic loading level in the study lane in excess of 200,000 ESAL/year.

(08) Environmental Effects in the Absence of Heavy Loads

The experiment on Environmental Effects in the Absence of Heavy Loads (SPS-8) examines the effect of climatic factors in the four environmental regions, subgrade type (frost-susceptible, expansive, fine, and coarse) on pavement sections incorporating flexible and rigid pavement designs that are subjected to limited traffic loading. The experiment design requires either two flexible pavement structures or two rigid pavement structures to be constructed at each site. The two flexible pavement sections consist of a 102-mm (4-inch) AC surface on 102-mm (8-inch) thick untreated granular base, and a 178-mm (7-inch) AC surface over a 305-mm (12-inch) thick granular base. The two rigid pavement test sections consist of doweled JPCP with PCC surface thicknesses of 203 mm (8 inches) and 279 mm (11 inches) PCC over a 152-mm (6-inch) thick dense-graded granular base. The pavement structures included in this study match pavement structures included in the SPS-1 and SPS-2 experiments. The experiment design stipulates that traffic volume in the study lane be at least 100 vehicles per day but not more than 10,000 ESAL/year. The flexible and rigid pavement sections may be constructed at the same site or at different sites.

(09) Validation of SHRP Asphalt Specifications and Mix Design

The SPS-9P pilot effort was launched at the end of the SHRP with the objective of gaining experience in implementing the Superpave® specifications. Test sections classified as SPS-9P were constructed using a very limited set of guidelines. In some instances, specifications were based on interim Superpave specifications that were changed at a later date. Many of the test sections were constructed before material sampling and testing guidelines were established.

The SPS-9A experiment, Superpave Asphalt Binder Study, requires construction of a minimum of two test sections at each project site. Construction may include new construction, reconstruction, or overlay. The minimum test sections consist of: 1) Highway agencies' standard mix, 2) Superpave Level 1 designed standard mix, and 3) Superpave mix with alternate binder grade either higher or lower than the specified Superpave binder. The minimum of two test sections at some sites results from the agency's declaration that the Superpave test section is the same as the standard agency mixture. This experiment will provide the opportunity to evaluate and improve the practical aspects of implementing the Superpave mix design through a hands-on field trial by interested highway agencies. It will also make it possible to compare the performance of the Superpave mixes and mixes designed with highway agencies' current asphalt specifications, asphalt-aggregate specifications, and mix design procedures. In addition, there will be an opportunity to test the sensitivity of the Superpave asphalt binder specifications relative to low temperature cracking, fatigue, and permanent deformation distress factors.

 

Table A.3. Pavement Type Codes
Type of Pavement Code
AC Surfaced Pavements:
AC with Granular Base 01
AC with Bituminous Treated Base 02
AC with Nonbituminous Treated Base 07
AC Overlay on AC Pavement 03
AC Overlay on JPCP Pavement 28
AC Overlay on JRCP Pavement 29
AC Overlay on CRCP Pavement 30
Other 10
PCC Surfaced Pavements:
JPCP—Placed Directly on Untreated Subgrade 11
JRCP—Placed Directly on Untreated Subgrade 12
CRCP—Placed Directly on Untreated Subgrade 13
JPCP—Placed Directly on Treated Subgrade 14
JRCP—Placed Directly on Treated Subgrade 15
CRCP—Placed Directly on Treated Subgrade 16
JPCP over Unbound Base 17
JRCP over Unbound Base 18
CRCP over Unbound Base 19
JPCP over Bituminous Treated Base 20
JRCP over Bituminous Treated Base 21
CRCP over Bituminous Treated Base 22
JPCP over Nonbituminous Treated Base 23
JRCP over Nonbituminous Treated Base 24
CRCP over Nonbituminous Treated Base 25
JPCP Overlay on JPCP Pavement 31
JPCP Overlay on JRCP Pavement 33
JPCP Overlay on CRCP Pavement 35
JRCP Overlay on JPCP Pavement 32
JRCP Overlay on JRCP Pavement 34
JRCP Overlay on CRCP Pavement 36
CRCP Overlay on JPCP Pavement 38
CRCP Overlay on JRCP Pavement 39
CRCP Overlay on CRCP Pavement 37
JPCP Overlay on AC Pavement 04
JRCP Overlay on AC Pavement 05
CRCP Overlay on AC Pavement 06
Prestressed Concrete Pavement 40
Other 49
*Composite Pavements (Wearing Surface Included in Initial Construction):
JPCP with Asphalt Concrete Wearing Surface 51
JRCP with Asphalt Concrete Wearing Surface 52
CRCP with Asphalt Concrete Wearing Surface 53
Other 59

*"Composite Pavements" are pavements originally constructed with an AC wearing surface over a PCC slab (1986 "AASHTO Guide for Design of Pavement Structures").

 

Table A.4. Pavement Surface Material Type Classification Codes
Material Type Code
Hot-Mixed, Hot-Laid Asphalt Concrete, Dense Graded 01
Hot-Mixed, Hot-Laid Asphalt Concrete, Open Graded (Porous Friction Course) 02
Sand Asphalt 03
PCC (JPCP) 04
PCC (JRCP) 05
PCC (CRCP) 06
PCC (Prestressed) 07
PCC (Fiber Reinforced) 08
Plain PCC (Only Used for SPS-7 Overlays of CRCP) 90
Plant Mix (Emulsified Asphalt) Material, Cold Laid 09
Plant Mix (Cutback Asphalt) Material, Cold Laid 10
Single Surface Treatment 11
Double Surface Treatment 12
Recycled Asphalt Concrete
Hot-Laid, Central Plant Mix 13
Cold-Laid, Central Plant Mix 14
Cold-Laid, Mixed-In-Place 15
Heater Scarification/Recompaction 16
Recycled PCC
JPCP 17
JRCP 18
CRCP 19
Other 20

 

Table A.5. Base and Subbase Material Type Classification Codes
Material Type Code
Gravel (Uncrushed) 22
Crushed Stone, Gravel or Slag 23
Sand 24
Soil-Aggregate Mixture (Predominantly Fine-Grained Soil) 25
Soil-Aggregate Mixture (Predominantly Coarse-Grained Soil) 26
Soil Cement 27
Asphalt Bound Base or Subbase Materials
Dense-Graded, Hot-Laid, Central Plant Mix 28
Dense-Graded, Cold-Laid, Central Plant Mix 29
Dense-Graded, Cold-Laid, Mixed-In-Place 30
Open-Graded, Hot-Laid, Central Plant Mix 31
Open-Graded, Cold-Laid, Central Plant Mix 32
Open-Graded, Cold-Laid, Mixed-In-Place 33
Recycled Asphalt Concrete, Plant Mix, Hot Laid 34
Recycled Asphalt Concrete, Plant Mix, Cold Laid 35
Recycled Asphalt Concrete, Mixed-In-Place 36
Sand Asphalt 46
Cement-Aggregate Mixture 37
Lean Concrete (<3 sacks cement/cubic yard) 38
Recycled PCC 39
Sand-Shell Mixture 40
Limerock, Caliche (Soft Carbonate Rock) 41
Lime-Treated Subgrade Soil 42
Cement-Treated Subgrade Soil 43
Pozzolanic-Aggregate Mixture 44
Cracked and Seated PCC Layer 45
Other 49

 

Table A.6. Subgrade Soil Description Codes
Soil Description Code
Fine-Grained Subgrade Soils
Clay (Liquid Limit > 50) 51
Sandy Clay 52
Silty Clay 53
Silt 54
Sandy Silt 55
Clayey Silt 56
Coarse-Grained Subgrade Soils
Sand 57
Poorly Graded Sand 58
Silty Sand 59
Clayey Sand 60
Gravel 61
Poorly Graded Gravel 62
Clayey Gravel 63
Shale 64
Rock 65

 

Table A.7. Material Type Codes for Thin Seals and Interlayers
Material Type Code
Grout 70
Chip Seal Coat 71
Slurry Seal Coat 72
Fog Seal Coat 73
Woven Geotextile 74
Nonwoven Geotextile 75
Stress Absorbing Membrane Interlayer 77
Dense-Graded Asphalt Concrete Interlayer 78
Aggregate Interlayer 79
Open-Graded Asphalt Concrete Interlayer 80
Chip Seal with Modified Binder (Does Not Include Crumb Rubber) 81
Sand Seal 82
Asphalt-Rubber Seal Coat (Stress Absorbing Membrane) 83
Sand Asphalt 84
Other 85
Thin Seal Interlayer 86
Plain Portland Cement Concrete (Only Used for SPS-7) 90

 

Table A.8. Geologic Classification Codes
Material Code
Igneous
Granite 01
Syenite 02
Diorite 03
Gabbro 04
Peridotite 05
Felsite 06
Basalt 07
Diabase 08
Sedimentary
Limestone 09
Dolomite 10
Shale 11
Sandstone 12
Chert 13
Conglomerate 14
Breccia 15
Metamorphic
Gneiss 16
Schist 17
Amphibolite 18
Slate 19
Quartzite 20
Marble 21
Serpentine 22
Other Rock Type (Specify if Possible or Unknown) 30
Glacial Soils
Glacial Soils 31
Boulder Clay 32
Glacial Sands and Gravels 33
Laminated Silts and Laminated Clays 34
Varved Clays 35
Ground Moraine 36
Fluvio-Glacial Sands and Gravels 37
Other Glacial Soils 38

 

Table A.8. Geologic Classification Codes (Continued)
Material Code
Residual Soils
Plateau Gravels 40
River Gravels 41
Alluvium 42
Alluvial Clays and/or Peat 43
Alluvial Silt 44
Other Alluvial Soils 45
Coastal Shingle and Beach Deposits 46
Wind-Blown Sand 47
Loess (Collapsible Soil) 48
Shale, Siltstone, Mudstone, Claystone 49
Expansive Soils 50
Residual Soils 51
Residual Soils Derived from Granites, Gneisses, and Schists 52
Residual Soils Derived from Limestone, Sandstone, and Shale 53
Other Residual Soils 54
Coquina 55
Shell 56
Marl 58
Caliche 59
Other 60

 

Table A.9. Soil and Soil-Aggregate Mixture Type Codes, AASHTO Classification
AASHTO Classification Code
A-1-a 01
A-1-b 02
A-3 03
A-2-4 04
A-2-5 05
A-2-6 06
A-2-7 07
A-4 08
A-5 09
A-6 10
A-7-5 11
A-7-6 12

 

Table A.10. Portland Cement Type Codes
Portland Cement Type Code
Type I 41
Type II 42
Type III 43
Type IV 44
Type V 45
Type IS 46
Type ISA 47
Type IA 48
Type IIA 49
Type IIIA 50
Type IP 51
Type IPA 52
Type N 53
Type NA 54
Other 55

 

Table A.11. Portland Cement Concrete Admixture Codes
PCC Admixture Code
Water-Reducing (AASHTO M194, Type A) 01
Retarding (AASHTO M194, Type B) 02
Accelerating (AASHTO M194, Type C) 03
Water-Reducing and Retarding (AASHTO M194, Type D) 04
Water-Reducing and Accelerating (AASHTO M194, Type E) 05
Water-Reducing, High Range (AASHTO M194, Type F) 06
Water-Reducing, High Range and Retarding (AASHTO M194, Type G) 07
Air-Entraining Admixture (AASHTO M154) 08
Natural Pozzolans (AASHTO M295, Class N) 09
Fly Ash, Class F (AASHTO M295) 10
Fly Ash, Class C (AASHTO M295) 11
Other (Chemical) 12
Other (Mineral) 13

 

Table A.12. Aggregate Durability Test Type Codes
Description AASHTO ASTM Code
Resistance to Abrasion of Small Size Coarse Aggregate by Use of Los Angeles Machine (Percent Weight Loss) T96 C131 01
Soundness of Aggregate by Freezing and Thawing (Percent Weight Loss) T103 - 02
Soundness of Aggregate by Use of Sodium Sulfate or Magnesium Sulfate (Percent Weight Loss) T104 C88 03
Resistance to Degradation of Large-Size Coarse Aggregate by Abrasion and Impact in the Los Angeles Machine (Percent Weight Loss) - C535 04
Potential Volume Change of Cement-Aggregate Combinations (Percent Expansion) - C342 05
Evaluation of Frost Resistance of Coarse Aggregates in Air-Entrained Concrete by Critical Dilution Procedures (Number of Weeks of Frost Immunity) - C682 06
Potential Alkali Reactivity of Cement Aggregate Combinations (Average Percent Expansion) - C227 07
Potential Reactivity of Aggregates (Reduction in Alkalinity-mmol/L) - C289 08
Test for Clay Lumps and Friable Particles in Aggregates (Percent by Weight) T112 C142 09
Test for Potential Alkali Reactivity of Carbonate Rocks for Concrete Aggregates (Percent Change in Specimen Length) - C586 11

 

Table A.13. Codes for Asphalt Refiners and Processors in the United States*
Refiner/Processor Code
Belcher Refining Co.—Mobile Bay, AL 78
Hunt Refining Co.—Tuscaloosa, AL 01
Chevron USA, Inc.—Kenai, AK 02
Mapco Alaska Petroleum—North Pole, AK 03
Intermountain Refining Cl.—Fredonia, AZ 04
Berry Petroleum Company—Stevens, AR 05
Cross Oil and Refining Company—Smackover, AR 06
Lion Oil Company—El Dorado, AR 07
McMillan Ring, Free Oil Cl.—Norphlet, AR 08
Chevron USA, Inc.—Richmond, CA 09
Conoco, Inc.—Santa Maria, CA 10
Edgington Oil Co., Inc.—Long Beach, CA 11
Golden Bear Division, Witco Chemical Corp.—Oildale, CA 12
Golden West Refining, Co.—Santa Fe Springs, CA 13
Huntway Refining Co.—Benicia, CA 14
Huntway Refining Co.—Wilmington, CA 15
Lunday-Thagard Co.—South Gate, CA 79
Newhall Refining Co., Inc.—Newhall, CA 16
Oxnard Refining—Oxnard, CA 17
Paramount Petroleum Corp.—Paramount, CA 80
Powerline Oil Co.—Santa Fe Springs, CA 81
San Joaquin Refining Cl.—Bakersfield, CA 18
Shell Oil Co.—Martinez, CA 19
Superior Processing Co.—Santa Fe Springs, CA 20
Colorado Refining Co.—Commerce City, CO 82
Conoco, Inc.—Commerce City, CO 21
Amoco Oil, Inc.—Savannah, GA 22
Young Refining Corp.—Douglasville, GA 23
Chevron USA, Inc.—Barber's Point, HI 24
Clark Oil and Refining Corp.—Blue Island, IL 25
Shell Oil Co.—Wood River, IL 26
Unacol Corp.—Lemont, IL 27
Amoco Oil Co.—Whiting, IN 28
Laketon Refining Corp.—Laketon, IN 83
Young Refining Corp.—Laketon, IN 29
Derby Refining Co.—El Dorado, KS 84
Farmland Industries, Inc.—Phillipsburg, KS 30
Total Petroleum, Inc.—Arkansas City, KS 31
Ashland Petroleum Co.—Catlettsburg, KY 32
Atlas Processing Co.—Shreveport, LA 33
Calumet Refining Co.—Princeton, LA 34
Exxon Co.—Baton Rouge, LA 35

 

Table A.13. Codes for Asphalt Refiners and Processors in the United States* (Continued)
Refiner/Processor Code
Marathon Petroleum Co.—Garyville, LA 36
Marathon Petroleum Co.—Detroit, MI 37
Ashland Petroleum Co.—St. Paul, MN 38
Koch Refining Co.—Rosemount, MN 39
Chevron USA, Inc.—Pascagoula, MS 40
Ergon Refining Inc.—Vicksburg, MS 41
Southland Oil Co.—Lumberton, MS 42
Southland Oil Co.—Sanderson, MS 43
Cenex—Laurel, MT 44
Conoco, Inc.—Billings, MT 45
Exxon Co.—Billings, MT 46
Chevron USA, Inc.—Perth Amboy, NJ 47
Exxon Co.—Linden, NJ 48
Giant Industries, Inc.—Gallup, NM 85
Navahoe Refining Co.—Artesia, NM 49
Cibro Petroleum Products Co.—Albany, NY 86
Ashland Petroleum Co.—Canton, OH 50
Standard Oil Co.—Toledo, OH 51
Sohio Oil Co. (BP America)—Toledo, OH 87
Kerr-McGee Refining Co.—Wynnewood, OK 52
Sinclair Oil Corp.—Tulsa, OK 53
Sun Co.—Tulsa, OK 54
Total Petroleum, Inc.—Ardmore, OK 55
Chevron USA, Inc.—Portland, OR 56
Atlantic Refining & Marketing Corp.—Philadelphia, PA 57
United Refining Co.—Warren, PA 58
Mapco Petroleum, Inc.—Memphis, TN 59
Charter International Oil Co.—Houston, TX 60
Chevron USA, Inc.—El Paso, TX 61
Coastal Refining & Marketing, Inc.—Corpus Christi, TX 88
Coastal States Petroleum Co.—Corpus Christi, TX 62
Diamond Shamrock Corp.—Sunray, TX 63
Exxon Co. USA—Baytown, TX 64
Fina Oil and Chemical Co.—Big Spring, TX 65
Fina Oil and Chemical Co.—Port Arthur, TX 89
Hill Petroleum Co.—Houston, TX 90
Shell Oil Co.—Deer Park, TX 66
Star Enterprise—Port Arthur & Port Neches, TX 91
Texaco Refining & Marketing, Inc.—Port Arthur & Port Neches, TX 67
Trifinery—Corpus Christi, TX 92
Unocal Corp.—Nederland, TX 68

 

Table A.13. Codes for Asphalt Refiners and Processors in the United States* (Continued)
Refiner/Processor Code
Valero Refining Co.—Corpus Christi, TX 69
Phillips 66 Co.—Woods Cross, UT 70
Chevron USA Inc.—Seattle, WA 71
Sound Refining, Inc.—Tacoma, WA 72
US Oil and Refining Co.—Tacoma, WA 73
Murphy Oil USA, Inc.—Superior, WI 74
Big West Oil Co.—Cheyenne, WY 75
Little America Refining Co.—Casper, WY 93
Sinclair Oil Corp.—Sinclair, WY 76
Other 77

*Originally taken from Oil and Gas Journal, March 20, 1989, pp. 72-89 and updated October 1993.

 

Table A.14. Asphalt Cement Modifier Codes
Asphalt Cement Modifiers Code
Stone Dust 01
Lime 02
Portland Cement 03
Carbon Black 04
Sulfur 05
Lignin 06
Natural Latex 07
Synthetic Latex 08
Block Copolymer 09
Reclaimed Rubber 10
Polyethylene 11
Polypropylene 12
Ethylene-Vinyl Acetate 13
Polyvinyl Chloride 14
Asbestos 15
Rock Wool 16
Polyester 17
Manganese 18
Other Mineral Salts 19
Lead Compounds 20
Carbon 21
Calcium Salts 22
Recycling Agents 23
Rejuvenating Oils 24
Amines 25
Fly Ash 26
Other 27

 

Table A.15. Grades of Asphalt, Emulsified Asphalt, and Cutback Asphalt Codes
Asphalts Code
Asphalt Cements
AC-2.5 01
AC-5 02
AC-10 03
AC-20 04
AC-30 05
AC-40 06
AR-1000 (AR-10 by AASHTO Designation) 07
AR-2000 (AR-20 by AASHTO Designation) 08
AR-4000 (AR-40 by AASHTO Designation) 09
AR-8000 (AR-80 by AASHTO Designation) 10
AR-16000 (AR-160 by AASHTO Designation) 11
200-300 pen 12
120-150 pen 13
85-100 pen 14
60-70 pen 15
40-50 pen 16
Other Asphalt Cement Grade 17
Emulsified Asphalts
RS-1 18
RS-2 19
MS-1 20
MS-2 21
MS-2h 22
HFMS-1 23
HFMS-2 24
HFMS-2h 25
HFMS-2s 26
SS-1 27
SS-1h 28
CRS-1 29
CRS-2 30
CMS-2 31
CMS-2h 32
CSS-1 33
CSS-1h 34
Other Emulsified Asphalt Grades 35
Cutback Asphalts (RC, MC, SC)
30 (MC only) 36
70 37
250 38
800 39
3000 40
Other Cutback Asphalt Grade 99

Taken from Manual Series No. 5 (MS-5), "A Brief Introduction to Asphalt," and Specification Series No. 2 (SS-2), "Specifications for Paving and Industrial Asphalts," both publications by the Asphalt Institute.

 

Table A.16. Maintenance and Rehabilitation Work Type Codes
Maintenance and Rehabilitation Work Type Codes
Crack Sealing (linear ft) 01
Transverse Joint Sealing (linear ft) 02
Lane-Shoulder Longitudinal Joint Sealing (linear ft) 03
Full Depth Joint Repair Patching of PCC (sq. yards) 04
Full Depth Patching of PCC Pavement Other than at Joint (sq. yards) 05
Partial Depth Patching of PCC Pavement Other than at Joint (sq. yards) 06
PCC Slab Replacement (sq. yards) 07
PCC Shoulder Restoration (sq. yards) 08
PCC Shoulder Replacement (sq. yards) 09
AC Shoulder Restoration (sq. yards) 10
AC Shoulder Replacement (sq. yards) 11
Grinding/Milling Surface (sq. yards) 12
Grooving Surface (sq. yards) 13
Pressure Grout Subsealing (no. of holes) 14
Slab Jacking Depressions (no. of depressions) 15
Asphalt Subsealing (no. of holes) 16
Spreading of Sand or Aggregate (sq. yards) 17
Reconstruction (Removal and Replacement) (sq. yards) 18
Asphalt Concrete Overlay (sq. yards) 19
Portland Cement Concrete Overlay (sq. yards) 20
Mechanical Premix Patch (Using Motor Grader and Roller) (sq. yards) 21
Manual Premix Spot Patch (Hand Spreading and Compacting with Roller) (sq. yards) 22
Machine Premix Patch (Placing Premix with Paver, Compacting with Roller) (sq. yards) 23
Full Depth Patch of AC Pavement (Removing Damaged Material, Repairing Supporting Material, and Repairing) (sq. yards) 24
Patch Pot Holes—Hand Spread, Compacted with Truck (no. of holes) 25
Skin Patching (Hand Tools/Hot Pot to Apply Liquid Asphalt and Aggregate) (sq. yards) 26
Strip Patching (Using Spreader and Distributor to Apply Hot Liquid Asphalt and Aggregate) (sq. yards) 27
Surface Treatment, Single Layer (sq. yards) 28
Surface Treatment, Double Layer (sq. yards) 29
Surface Treatment, Three or More Layers (sq. yards) 30
Aggregate Seal Coat (sq. yards) 31
Sand Seal Coat (sq. yards) 32
Slurry Seal Coat (sq. yards) 33
Fog Seal Coat (sq. yards) 34
Prime Coat (sq. yards) 35
Tack Coat (sq. yards) 36
Dust Layering (sq. yards) 37

 

Table A.16. Maintenance and Rehabilitation Work Type Codes (Continued)
Maintenance and Rehabilitation Work Type Codes
Longitudinal Subdrains (linear ft) 38
Transverse Subdrainage (linear ft) 39
Drainage Blanket (sq. yards) 40
Well System 41
Drainage Blankets with Longitudinal Drains 42
Hot-Mix Recycled Asphalt Concrete (sq. yards) 43
Cold-Mix Recycled Asphalt Concrete (sq. yards) 44
Heater Scarification, Surface Recycled Asphalt Concrete (sq. yards) 45
Fracture Treatment of PCC Pavement as Base for New AC Surface (sq. yards) 46
Fracture Treatment of PCC Pavement as Base for New PCC Surface (sq. yards) 47
Recycled PCC (sq. yards) 48
Pressure Relief Joints in PCC Pavements (linear feet) 49
Joint Load Transfer Restoration in PCC Pavements (linear ft) 50
Mill off Existing AC Pavement and Overlay with AC (sq. yards) 51
Mill off Existing AC Pavement and Overlay with PCC (sq. yards) 52
Other 53
Partial Depth Patching of PCC Pavement at Joints (sq. yards) 54
Mill Existing Pavement and Overlay with Hot-Mix Recycled Asphalt Concrete (sq. yards) 55
Mill Existing Pavement and Overlay with Cold-Mix Recycled Asphalt Concrete (sq. yards) 56
Saw and Seal (linear ft.) 57

 

Table A.17. Maintenance Location Codes
Maintenance Location Code
Outside Lane (Number 1) 01
Inside Lane (Number 2) 02
Inside Lane (Number 3) 03
All Lanes 09
Shoulder 04
All Lanes Plus Shoulder 10
Curb and Gutter 05
Side Ditch 06
Culvert 07
Other 08

Note: LTPP only studies outside lanes.

 

Table A.18. Maintenance Materials Type Codes
Maintenance Materials Type Code
Preformed Joint Fillers 01
Hot-Poured Joint and Crack Sealer 02
Cold-Poured Joint and Crack Sealer 03
Open Graded Asphalt Concrete 04
Hot-Mix Asphalt Concrete Laid Hot 05
Hot-Mix Asphalt Concrete Laid Cold 06
Sand Asphalt 07
PCC (Overlay Replacement)
Joint Plain (JPCP) 08
Joint Reinforced (JRCP) 09
Continuously Reinforced (CRCP) 10
PCC (Patches) 11
Hot Liquid Asphalt and Aggregate (Seal Coat) 12
Hot Liquid Asphalt and Mineral Aggregate 13
Hot Liquid Asphalt and Sand 14
Emulsified Asphalt and Aggregate (Seal Coat) 15
Emulsified Asphalt and Mineral Aggregate 16
Emulsified Asphalt and Sand 17
Hot Liquid Asphalt 18
Emulsified Asphalt 19
Sand Cement (Using Portland Cement) 20
Lime Treated or Stabilized Materials 21
Cement Treated or Stabilized Materials 22
Cement Grout 23
Aggregate (Gravel, Crushed Stone, or Slag) 24
Sand 25
Mineral Dust 26
Mineral Filler 27
Other 28

 

Table A.19. Recycling Agent Type Codes
Recycling Agent Code
RA 1 42
RA 5 43
RA 25 44
RA 75 45
RA 250 46
RA 500 47
Other 48

Note: The recycling agent groups shown in this table are defined in ASTM D4552.

 

Table A.20. Antistripping Agent Type Codes
Antistripping Agent Code
Permatac 01
Permatac Plus 02
Betascan Roads 03
Pavebond 04
Pavebond Special 05
Pavebond Plus 06
BA 2000 07
BA 2001 08
Unichem "A" 09
Unichem "B" 10
Unichem "C" 11
Aquashield AS4115 12
Aquashield AS4112 13
Aquashield AS4113 14
Portland Cement 15
Hydrated Lime:
Mixed Dry with Asphalt Cement 16
Mixed Dry with Dry Aggregate 17
Mixed Dry with Wet Aggregate 18
Slurried Lime Mixed with Aggregate 19
Hot Lime Slurry (Quick Lime Slaked and Slurried at Job Site) 20
No Strip Chemicals A-500 21
No Strip Chemical Works ACRA RP-A 22
No Strip Chemical Works ACRA Super Conc. 23
No Strip Chemical Works ACRA 200 24
No Strip Chemical Works ACRA 300 25
No Strip Chemical Works ACRA 400 26
No Strip Chemical Works ACRA 500 27
No Strip Chemical Works ACRA 512 28
No Strip Chemical Works ACRA 600 29
Darakote 30
De Hydro H86C 31
Emery 17065 32
Emery 17319 33
Emery 17319-6880 34
Emery 17320 35
Emery 17321 36
Emery 17322 37
Emery 17339 38
Emery 1765-6860 39
Emery 6886B 40
Husky Antistrip 41

 

Table A.20. Antistripping Agent Type Codes (Continued)
Antistripping Agent Code
Indulin AS-Special 42
Indulin AS-1 43
Jetco AD-8 44
Kling 45
Kling-Beta ZP-251 46
Kling-Beta L-75 47
Kling-Beta LV 48
Kling-Beta 1000 49
Kling-Beta 200 50
Nacco Antistrip 51
No Strip 52
No Strip Concentrate 53
Redi-Coat 80-S 54
Redi-Coat 82-S 55
Silicone 56
Super AD-50 57
Tap Co 206 58
Techni H1B7175 59
Techni H1B7173 60
Techni H1B7176 61
Techni H1B7177 62
Tretolite DH-8 63
Tretolite H-86 64
Tretolite H-86C 65
Tyfo A-45 66
Tyfo A-65 67
Tyfo A-40 68
Edoco 7003 69
Other 70
No Antistripping Agent Used 00

 

Table A.21. Distress Types
Distress Type Code
AC Pavement
Alligator Cracking 01
Block Cracking 02
Edge Cracking 03
Longitudinal Cracking 04
Reflection Cracking 05
Transverse Cracking 06
Patch Deterioration 07
Potholes 08
Rutting 09
Shoving 10
Bleeding 11
Polished Aggregate 12
Raveling and Weathering 13
Lane Shoulder Dropoff 14
Water Bleeding 15
Pumping 16
Other 17
PCC Pavement
Corner Breaks 20
Durability Cracking 21
Longitudinal Cracking 22
Transverse Cracking 23
Joint Seal Damage 24
Spalling 25
Map Cracking/Scaling 26
Polished Aggregate 27
Popouts 28
Punchouts 29
Blowouts 30
Faulting 31
Lane/Shoulder Dropoff 32
Lane/Shoulder Separation 33
Patch Deterioration 34
Water Bleeding / Pumping 35
Slab Settlement 36
Slab Upheaval 37
Other 38

FHWA-HRT-06-066

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The Federal Highway Administration (FHWA) is a part of the U.S. Department of Transportation and is headquartered in Washington, D.C., with field offices across the United States. is a major agency of the U.S. Department of Transportation (DOT).
The Federal Highway Administration (FHWA) is a part of the U.S. Department of Transportation and is headquartered in Washington, D.C., with field offices across the United States. is a major agency of the U.S. Department of Transportation (DOT). Provide leadership and technology for the delivery of long life pavements that meet our customers needs and are safe, cost effective, and can be effectively maintained. Federal Highway Administration's (FHWA) R&T Web site portal, which provides access to or information about the Agency’s R&T program, projects, partnerships, publications, and results.
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