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Edward Garboczi, Yibing Zuo, Zhiwei Qian, Guang Ye
Many particle-based numerical models have been used to simulate the hydration process of cementitious materials. But most of these models employ regular shape particles, such as spheres, to represent cement, slag or fly ash, which neglect the influence of
Igor de la Varga, Javier Castro, Dale P. Bentz, Franco Zunino, Jason Weiss
Fly ash is frequently used as a replacement for cement in concrete. However, questions remain regarding the influence that fly ash has on the hydration of cement. This paper examines physical aspects (e.g., surface nucleation, cement particles spacing) and
Stephanie S. Watson, Chiara C. Ferraris, Jason D. Averill
The resilience of U.S. communities, defined as the "ability to withstand and recover rapidly from disruptive events," is directly dependent upon the ability of the built environment to maintain and support the functions upon which modern society has come
This report serves as the final report for a research project focused on increasing the usage of fly ash in transportation infrastructure. Specifically, this report addresses two phases of the research dealing with internal curing and early-age cracking
Didier Snoeck, Jianyun Wang, Dale P. Bentz, Nele De Belie
One of the major concerns in infrastructure repair is a sufficient bond between the substrate and the repair material, especially for the long-term performance and durability of the repaired structure. In this study, the bond of the repair material on the
Alex Olivas, Chiara C. Ferraris, Nicos Martys, Edward Garboczi, Blaza Toman, William L. George
Rheological measurements are often performed using a rotational rheometer. In this type of rheometer, the tested fluid is sheared between two surfaces, one of which acts as the rotating surface [1]. Usually, the rotational velocity is imposed and the
Pan Feng, Jeffrey W. Bullard, Edward Garboczi, Pan Feng
A recent microstructural model for simulating near-surface external sulfate attack on cement paste is modified to incorporate diffusive ionic transport between the surface and the interior of a macroscopic specimen. The model calculates the driving force
Gabriel Falzone, Magdalena Balonis, Dale P. Bentz, Scott Jones, Gaurav Sant
Chloride induced corrosion is a major cause of degradation of reinforced concrete infrastructure. While the binding of chloride ions (Cl-) by cementitious phases is known to delay corrosion, this approach has not been systematically exploited as a
Didier Snoeck, Jianyun Wang, Dale P. Bentz, Nele De Belie
The bond between repair mortars and existing concrete substrates is critical for the long-term performance and durability of the repaired structure. The carbonation state of the substrate is one of the parameters that may affect this bond strength. The
In situ digital holographic microscopy is used to characterize the dissolution flux of polycrystalline cubic tricalcium aluminate (C3A-c) in flowing water. The results show that C3A-c dissolves at rates that vary considerably with time and location
Tandre Oey, Isabella Pignatelli, Yingtian Yu, Narayanan Neithalath, Jeffrey W. Bullard, Mathieu Bauchy, Gaurav Sant
Fly ash which encompasses a mixture of glassy and crystalline aluminosilicates is an abundant supplementary cementitious material (SCM), valuable for replacing ordinary portland cement (OPC) as the binder fraction in concrete. As a result of the demand for
Emilio Hernandez-Bautista, Sadoth Sandoval-Torres, Prisciiano Cano Barrita, Dale P. Bentz
During steam curing of concrete, temperature and moisture gradients are developed, which are difficult to measure experimentally and can adversely affect the durability of concrete. In this research, a model of cement hydration coupled to moisture and heat
Tandre Oey, Jason Timmons, Paul E. Stutzman, Jeffrey W. Bullard, Magdalena Balonis, Mathieu Bauchy, Gaurav Sant
Fly ash is a critical yet underutilized material for partial replacement for ordinary portland cement (OPC) in the binder fraction of a concrete. Significant compositional variability, and a lack of rigorous classification methods currently limit fly ash
This chapter reviews ash quality and performance issues, with special emphasis on air entrainment and early-age performance. Recent developments in testing procedures are reviewed and recommendations are provided for standardized testing. One of the key
Joseph J. Biernacki, Jeffrey W. Bullard, Gaurav Sant, Nemkumar Banthia, Frederik P. Glasser, Scott Jones, Tyler Ley, Richard A Livingston, Luc Nicoleau, Jan Olek, Florence Sanchez, Rouzbeh Shahsavari, Paul E. Stutzman, Sobolev Konstantin, Tracie Prater
In a book published in 1906, Richard Meade outlined the history of portland cement up to that point1. Since then there has been great progress in portland cement-based construction materials technologies brought about by advances in the materials science
Pan Feng, Alexander Brand, Lei Chen, Jeffrey W. Bullard
Recent studies of topographical changes during dissolution at gypsum crystal surfaces focus on the formation and growth of etch pits because dissolution both parallel and normal to the surface is much faster at etch pits than at defect-free portions of the
Aditya Kumar, Tandre Oey, Gabriel Falzone, Jian Huang, Magdalena Balonis, Jeffrey W. Bullard, Gaurav Sant
The partial replacement of ordinary portland cement (OPC) by fine mineral fillers accelerates the rate of hydration reactions. This acceleration, known as the filler effect, has been attributed to enhanced heterogeneous nucleation of C-S-H on the extra
Robert Spragg, Scott Jones, Yiwen Bu, Yang Lu, Dale P. Bentz, Kenneth A. Snyder, Jason Weiss
Electrical tests have been used to characterize the microstructure of porous materials, the measured electrical response being determined by the contribution of the microstructure (porosity and tortuosity) and the electrical properties of the solution
Catherine Lucero, Robert Spragg, Dale P. Bentz, Daniel S. Hussey, David L. Jacobson, Jason Weiss
A portion of the concrete pavements in the US have recently been observed to have premature joint deterioration. While this damage has been attributed to a wide variety of potential factors, it is hypothesized that one component of this damage can be
Kyle Riding, Mohammadreza Mirzohosseini, Edward Garboczi
Recently, narrow particle size distributions, as measured by sieve analysis, of crushed waste glass were used as a replacement for Portland cement in concrete. Their chemical reactivity was successfully studied as a function of this measure of particle
Alex Olivas, Michelle A. Helsel, Nicos Martys, Chiara C. Ferraris, William L. George, Raissa Ferron
The conclusion of international studies was that the optimal approach to calibrate concrete rheometers would be to develop a non-Newtonian standard reference material (SRM) that contained inclusions similar in size to aggregates used commonly in concrete
Edward Garboczi, Rolands Cepuritis, Stefan Jacobsen
We studied the 3-D shape of concrete aggregate fines (3 µm to 250 µm) produced by high-speed VSI crushing of rock types from 10 different quarries representing a wide range of local Norwegian geological variety with respect to mineralogy and mechanical
Xiaodan Li, Zachary Grasley, Jeffrey W. Bullard, Edward Garboczi
When cementitious materials are dried, internal stresses are generated that lead to desiccation shrinkage. A portion of this shrinkage is irreversible. Based on previous research indicating that dissolution of cement grains while a cementitious composite
Hadi S. Esmaeeli, Yaghoob Farnam, Dale P. Bentz, Pablo Zavattieri, Jason Weiss
This paper presents a one-dimensional finite difference model that was developed to describe the freeze-thaw behavior of mortar containing deicing salt solution. The model is used to predict the temperature and the heat flow for mortar samples during
Scott Jones, Jeffery Davis, John L. Molloy, John R. Sieber, Dale P. Bentz
Chloride ingress into reinforced concrete structures is responsible for initiating corrosion of steel embedded into concrete. To aide in the prediction of concrete service life, a chloride ingress model that includes chloride binding to the cement matrix