Exploratory Advanced Research . . . Next Generation Transportation Solutions

with computer-modeling approaches. Researchers have been conducting the study in two 

phases: The first phase focused on the mechanisms of cement hydration, including the influence of aluminate and sulfate ions, and the 

second phase is currently investigating the 

influence of organic admixtures.

Cutting-Edge Techniques

For this study, researchers have been using 

both experimental measurement and modeling 

to reveal how chemical and surface interactions 

affect the kinetics of hydration reactions at early 

ages. The aim of the study is to establish findings that will lead to an unprecedented understanding of which chemical reactions occur, 

where they occur, at what rate, and how they 

can be modified. This comprehensive understanding will ultimately enable development of 

tools that engineers can use to predict the 

complex physical and chemical processes that 

control the setting, early-age and long-term 

strength, and durability of concrete. The end 

result will lead to important improvements in 

concrete durability, economy, strength, and 

sustainability, all of which will lead to better mix 

designs and longer lasting pavements. 

Researchers identified mechanisms to include 

in the new models by using experimental techniques such as vertical-scanning interferometry, 

tomography-assisted chemical correlation, and 

nuclear magnetic resonance spectroscopy. 

These techniques also provide previously unobtainable data to verify model predictions and to 

validate models at the nano-, micro-, and macroscopic length scales. During the course of the 

study, the researchers discovered new breakthrough techniques, which include combining 

nano-computed tomography and nano-x-ray 

fluorescent data to gather 3D chemistry data, 

allowing researchers to obtain even more information from a single scan of concrete materials. 

Because this technique can be used on a range 

of materials in which obtaining data on structure 

and chemistry is important, it holds great promise for the broader x-ray imaging community.

The Exploratory Advanced Research Program Fact Sheet

Innovations in Measurement 

and Modeling

Until recently, the primary obstacle to advancing the control of hydration in cement has been 

the inability to observe, measure, and model the 

process at the material’s length scales, which 

can range from nanometers to millimeters. This 

project’s innovation is that it focuses precisely 

on these length scales by using cutting-edge, 

experimental measurement techniques combined 

How does hydration affect the performance of concrete, including 

its setting, strength, and durability? Can 

advanced hydration models be developed 

that will allow practitioners to input the 

composition of cement, supplementary 

cementitious materials, and admixtures, 

combined with temperature, and receive 

guidance on a pavement’s expected 

performance? Answering these questions 

is the goal of the Exploratory Advanced 

Research (EAR) Program project “Mechanisms of Hydration and Setting of 

Ordinary Portland Cement in Simple and 

Complex Systems.” Princeton University 

is conducting this research, which is funded by the Federal Highway Administration 

(FHWA). Research partners for the project 

are the National Institute of Standards 

and Technology (NIST); Oklahoma State 

University; Rice University; University 

of California, Santa Barbara; and W.R. 

Grace and Company. 

Tools for Improving the Sustainability and Durability of Concrete

Modeling Hydration and Performance 
Breakthrough Advances 

This project’s breakthroughs in the measurement 

and analysis of concrete materials are matched 

by modeling advances that help researchers better design and interpret experiments. The resulting 

new understanding of hydration mechanisms and 

development has been used by the project 

researchers to improve the HydratiCA model 

developed by NIST, which is currently the most 

sophisticated tool for simulating hydration. The 

improved model will be able to generate both 

microscale and macroscale predictions of hydration behavior under a much wider range of conditions than previously possible. Researchers have 

also developed SimBNG, a boundary nucleation 

and growth model that is powerful but also fast 

enough and simple enough to be used in the field.

Gold Standard for Data

The project’s data will serve as the “gold standard” of hydration mechanism data for years to 

come. Following the conclusion of this project, 

FHWA will make data readily accessible to use in 

future modeling or experimentation undertaken 

by other researchers. A user-friendly database will 

allow researchers to access relevant data by technique, mineral, additive, and other key words. Data 

will include raw and processed images of concrete 

microstructures and nanostructures, combined 

with the techniques and specific settings used to 

obtain them. Data from the project are already 

being used to advance today’s pavement technology, including contributing to papers that have 

appeared in such publications as the Journal of 

the American Chemical Society, Cement and Concrete Research, and Acta Materialia.

Importance to FHWA

The 2009 Summit on Cement Hydration Kinetics 

and Modeling in Quebec, Canada, stimulated the 

concrete research community to take a fresh look 

at hydration. U.S. sponsors of the summit included FHWA and the National Science Foundation. 

Following the summit, NIST and FHWA issued a 

joint publication outlining their vision for needed 

research, NIST Special Publication 1138: Paving 

the Way for a More Sustainable Concrete Infrastructure: A Vision for Developing a Comprehensive Description of Cement Hydration Kinetics.

This project advances the joint research vision 

and addresses the modeling needs identified 

at the summit, including improving the ability 

of HydratiCA to predict hydration kinetics and 

infrastructure and developing SimBNG for use in 

the field. The SimBNG model in particular is a 

major step forward in meeting FHWA’s goal to 

improve models so that they give field engineers 

more agility in concrete materials selection and 

mixture qualification. 

Learn More

For more information on this project, contact 

Richard Meininger, FHWA Office of Infrastructure 

Research and Development, at 202-493-3191 

(email: richard.meininger@dot.gov). 

Tools for Improving the Sustainability and Durability of Concrete 

Modeling Hydration and Performance 

What Is the Exploratory 

Advanced Research Program?

FHWA’s Exploratory Advanced Research 

(EAR) Program focuses on longer term, 

higher risk research with a high payoff 

potential. The program addresses underlying gaps faced by applied highway 

research programs, anticipates emerging 

issues with national implications, and 

reflects broad transportation industry 

goals and objectives. To learn more about 

the EAR Program, visit the EAR Web site 

at www.fhwa.dot.gov/advancedresearch. 

The site features information on research 

solicitations, updates on ongoing research, 

links to published materials, summaries of 

past EAR Program events, and details on 

upcoming events. 

Publication No. 

FHWA-HRT-15-084

HRTM-30/11-15(WEB)E 

Photo credit, page 1: 

© Argonne National Laboratory, 

managed and operated by 

UChicago Argonne, LLC, for 

the U.S. Department of Energy.

Researchers conducted x-ray 

nano-computed tomography 

and nano-x-ray fluorescent 

imaging using the Beamline 26 

x-ray nanoprobe at Argonne 

National Laboratory in Illinois.