KEEPING OUR PARTNERS INFORMED

LTPP

Newsletter

May 2023

Spring Issue

LTPP Creates Analysis-Ready Datasets

The Long-Term Pavement 

Performance (LTPPTM) program 

has established more than 2,500 

pavement test sections since the 

program started collecting data 

in 1989, and significant amounts 

of performance data have been 

collected on each section, including 

surface distresses, longitudinal and 

transverse profiles, and surface 

deflections. In addition, the 

LTPP program has collected data 

quantifying the factors influencing 

performance, including pavement 

layer structure and material 

properties, climatic (moisture 

and temperature) conditions, 

traffic loadings and volumes, and 

construction features, all of which 

are stored in the LTPP database. 

Understanding and using the LTPP 

database requires knowledge 

of both the LTPP program and 

the database structure, which 

can be challenging for users. 

To address this user challenge, 

the LTPP program is developing 

analysis-ready datasets (ARDs) to 

help users obtain the appropriate 

data for their research projects.

LTPP data are typically distributed 

across multiple tables in the 

database, making some data 

elements hard to mine. A given data 

element may also have multiple 

values, making it difficult to know 

which value(s) to use, while in 

other cases missing values require 

imputation. In addition, users may 

have to interpret the data further to 

provide meaningful results. ARDs 

are a result of the data-wrangling 

effort, which organizes and groups 

data elements from multiple tables 

across the LTPP database and uses 

sound engineering judgment to 

compute the values for data users.

The first dataset created was the 

Analysis-Ready Materials Dataset 

(ARMAD), which solves the 

challenges for the layer thicknesses 

and material properties of LTPP 

test sections. The ARMAD was 

completed in the summer of 

2022 and is now available on the 

LTPP InfoPaveTM Web portal shown 

in figure 1. Please refer to the 

ARMAD TechBrief for a summary 

of how the dataset was created. 

Additional ARDs for performance, 

climate, and traffic are anticipated 

to be available in the portal 

this summer.

The LTPP program team is excited 

to provide these datasets to make 

the data easier to use for our 

customers. This data wrangling also 

Source: FHWA.

Figure 1. Screenshot. ARDs on the LTPP InfoPave Web portal.1

1

LTPP InfoPaveTM (web page). https://infopave.fhwa.dot.gov/, last accessed April 12, 2023.
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Spring 2023 Issue LTPP NEWSLETTER PAGE 2

results in data that can support 

pavement performance 

applications, including model 

calibrations and design software. 

For more information about the 

ARDs, contact Jane Jiang at 

jane.jiang@dot.gov.

MERRA-2 Data API for AASHTO 

Software Generating Buzz 

Among Pavement Researchers

The LTPP program has been 

hosting the National Aeronautics 

and Space Administration 

Modern-Era Retrospective Analysis 

for Research and Applications, 

Version 2 (MERRA-2) data on 

the LTPP InfoPave Web portal 

since 2017. The LTPP program 

has developed the capability 

in InfoPave to create an hourly 

climatic database (HCD) file that 

users can download and input into 

the AASHTOWare® Pavement 

ME Design software.2

 American 

Association of State Highway and 

Transportation Officials (AASHTO) 

design software users recommended 

simplifying the transfer of climate 

data from InfoPave. The Federal 

Highway Administration (FHWA) 

and AASHTO worked together to 

eliminate the required manual user 

interference and implemented an 

application programming interface 

(API), shown in figure 2, that 

provides functionality to directly 

select nine MERRA-2 cells nearest 

to a specified location. This API 

is integrated with AASHTOWare 

Pavement ME Design software 

to provide direct access to these 

HCD files from InfoPave for the 

required analysis.

LTPP Program Hosts 

Successful Events at 2023 

TRB Annual Meeting

The LTPP program hosted two 

successful events at the 102nd 

Transportation Research Board 

(TRB) annual meeting in January. 

The TRB Lectern Session 4049 on 

the LTPP program (sponsored by 

the TRB Standing Committee on 

Pavement Management Systems 

(AKT10) with cosponsorship by 

eight other pavement committees) 

was well attended. The LTPP 

program staff described the 

new ARDs (see featured article), 

the initiative to manage the 

data that will be collected from 

FHWA’s new pavement testing 

facility (which replaces the 

accelerated loading facility built in 

the 1990s), and the update of the 

LTPP data analysis plan. Ohhoon 

Kwon introduced the research 

© 2023 AASHTOWare® Pavement ME Design.

Figure 2. Screenshot. AASHTOWare Pavement ME Design API to select MERRA-2 cells.3

2

AASHTO. 2020. Mechanistic-Empirical Pavement Design Guide: A Manual of Practice, 3rd Edition. Washington, DC: American Association of State 

Highway and Transportation Officials.

3

AASHTO. 2015. AASHTOWare® Pavement ME Design (software).

“The ability to access InfoPave climate data directly from within the 

Pavement ME Design software is a valuable feature that speeds 

up the design process and makes life easier for pavement design 

engineers,” Clark S. Morrison, P.E., Ph.D., State Pavement Design 

Engineer for the North Carolina Department of Transportation and 

chairperson of the AASHTOWare Pavement ME Design Task Force.

Source: FHWA.

Figure 3. Photo. Participants of TRB Lectern Session 4049.

Note: Left to right, Deborah Walker (FHWA), Jian Liu (student contest second-place winner), Chuang Chen 

(student contest first-place winner), Jane Jiang (FHWA), Javier Ponce (FHWA), Larry Wiser (FHWA), 

Craig Thor (FHWA), Ohhoon Kwon (Florida Department of Transportation).
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Spring 2023 Issue LTPP NEWSLETTER PAGE 3

being conducted at Florida’s 

pavement testing facility, and the 

first-place winner of the Long-Term 

Infrastructure Performance (LTIP) 

student data analysis contest 

presented his analysis study.

TRB Workshop 1024–Use of 

Available Data to Extend the Life 

of Highway Infrastructure was a 

joint event with the Long-Term 

Bridge Performance Program and 

was sponsored by the TRB Section 

on Pavements (AKP00) with 

cosponsorship by 10 other pavement 

and structures committees. 

Presentations from experts across 

both the pavement and bridge 

professions addressed the work 

to collect, understand, organize, 

analyze, and foster trust in the data 

and their supporting information. 

A lively panel discussion also 

occurred in which the members and 

audience provided their views on the 

questions: How do we get people 

to use the data that we have? How 

can we effectively use the data? 

Are current data-collection efforts 

addressing analysis needs?

The workshop will be summarized 

in a document that will include the 

next steps to help pavement and 

bridge asset owners use available 

data to extend infrastructure 

life. For a copy of the workshop 

summary or presentations from the 

lectern or workshop events, please 

contact the LTPP Customer Support 

Service Center at ltppinfo@dot.gov.

In Brief

Winners of the 2022 Student 

Data Analysis Contest

Four papers were selected for 

awards in the LTIP student data 

analysis contest. The student 

winners are as follows:

• Chan Yang, Ph.D. candidate; 

Peng Lou, Ph.D., research 

associate; and Hani Nassif, 

P.E., Ph.D., professor and 

director. Rutgers, the State 

University of New Jersey. First 

place (Bridge): “Correlation of 

Bridge Deck Deterioration with 

Truck Load Spectra based on 

Weigh-In-Motion Data.”

• Chuang Chen, Ph.D. student; 

Yong Deng, postdoctoral research 

associate; Mengyan Li, assistant 

professor (Bentley University); 

and Xianming Shi, professor. 

Washington State University. 

First place (Pavement): “Key 

Climatic Factors Affecting Asphalt 

Pavement Roughness Differ 

in Different Climate Regions: 

Exploratory Analyses.”

• Jian Liu, Ph.D. candidate; 

and Linbing Wang, Ph.D., P.E., 

professor. Virginia Polytechnic 

Institute and State University. 

Second place (Pavement): 

“Optimizing Asphalt Mix 

Design Considering IRI of 

Asphalt Pavement Predicted 

Using Autoencoders and 

Machine Learning.”

• Muhamad Munum Masud, 

graduate research assistant; and 

Syed Waqar Haider, Ph.D., P.E. 

associate professor. Michigan 

State University. Third place 

(Pavement): “Relationship 

between Gross Vehicle Weight 

with Commercial Freight 

Tonnage—Case Studies Based 

on LTPP WIM Data.”

Congratulations to the winners 

and thank you to everyone 

who participated. This year’s 

LTIP Student Data Analysis Contest

is underway, and papers are due 

August 1, 2023.

Transportation Pooled 

Fund Solicitations

Two active Transportation Pooled 

Fund Program research projects 

involve the LTPP program. One 

continues the forensic investigations 

of LTPP test sections (LTPP Forensic 

Investigations - Stage 2 TPF-5(500)), 

and the other evaluates and 

documents the long-term 

performance of pavement 

preservation treatments 

(National Partnership to Improve the 

Quality of Preventive Maintenance 

Treatment Construction & Data 

Collection Practices (PG Phase III) 

Solicitation 1581). Please consider 

being a partner in these new efforts.

New Publications

Reports

Long-Term Pavement Performance 

Warm-Mix Asphalt Study, Volume I: 

Final Report

[FHWA-HRT-22-018 PDF]

Figure 4. Photo. Winners of the 2022 

LTIP student data analysis contest at the 

LTPP program lectern session.

Note: Left to right, Jian Liu (student contest 

second-place winner) and Chuang Chen (student 

contest first-place winner).

Source: FHWA.
Spring 2023 Issue LTPP NEWSLETTER PAGE 4

HRDI-30/05-23(WEB)E

FHWA-HRT-23-079

Recommended citation: Federal Highway Administration, 

LTPP Newsletter Spring 2023 Issue (Washington, DC: 2023) 

https://doi.org/10.21949/1521384.

Long-Term Pavement Performance 

Warm-Mix Asphalt Study Final Report, 

Volume II: SPS-10 Experimental 

Matrix and Research Plan 

[FHWA-HRT-22-019 PDF]

Long-Term Pavement Performance 

Warm-Mix Asphalt Study Final 

Report, Volume III: SPS-10 

Nomination Guidelines

[FHWA HRT-22-020 PDF]

Long-Term Pavement Performance 

Warm-Mix Asphalt Study Final 

Report, Volume IV: SPS-10 Materials 

Sampling and Testing Requirements

[FHWA-HRT-22-021 PDF]

Long-Term Pavement Performance 

Warm-Mix Asphalt Study Final Report, 

Volume V: SPS-10 Performance 

Monitoring Guide

[FHWA-HRT-22-022 PDF]

Long-Term Pavement Performance 

Warm-Mix Asphalt Study Final Report, 

Volume VI: SPS-10 Construction 

Documentation Guide

[FHWA-HRT-22-023 PDF]

TechBriefs 

Effects of Seasonal and Diurnal FWD 

Measurements on LTE of JPCP—LTPP

SMP Data

[FHWA HRT-22-094 PDF]

Introduction to the LTPP 

Analysis-Ready Materials 

Dataset (ARMAD)

[FHWA HRT-22-114 PDF]

Research Note

LTPP Analysis-Ready Materials 

Dataset (ARMAD) Release 

Research Note

[FHWA-HRT-22-079 PDF]

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