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Edward Garboczi, Zhiwei Qian, Erik Schlangen, Guang Ye
The mesostructures of mortar and concrete can be represented by a model consisting of particles (sand, gravel) embedded in a cement paste matrix. Traditionally, spheres have been used to represent aggregates because of their simplicity, although the
Yaghoob Farnam, Dale P. Bentz, Allison Hampton, Jason Weiss
This paper describes a series of experiments that were performed to assess the freeze-thaw behavior of mortar samples exposed to NaCl solutions. A low-temperature longitudinal guarded comparative calorimeter was used to perform cyclic freeze-thaw testing
Emilio Hernandez-Bautista, Dale P. Bentz, Sadoth Sandoval-Torres, Prisciiano Cano Barrita
Steam curing under atmospheric pressure is used routinely in the precast concrete industry because of the increase in compressive strength up to 70 % obtained in only one day. However, this process requires high-energy consumption to maintain a constant
Emilio Hernandez-Bautista, Dale P. Bentz, Sadoth Sandoval-Torres, Prisciiano Cano Barrita
The process of accelerated curing of pre-cast concrete consists in increasing the temperature within a saturated water vapor atmosphere during several hours. In this process, the cement hydration has a significant importance in the thermal behavior of
Luca Valentini, Matteo Parisatto, Vincenzo Russo, Giorgio Ferrari, Jeffrey W. Bullard, Ross J. Angel, Maria C. Dalconi, Gilberto Artioli
The ability of the VCCTL microstructural model to predict the hydration kinetics and elastic moduli of cement materials was tested by coupling a series of computer simulations and laboratory experiments, using different cements. The novel aspects of this
Robert Spragg, Scott Jones, Kenneth A. Snyder, Dale P. Bentz, Chiara Villani, Jason Weiss
Electrical measurements are becoming a common method to assess the transport properties of concrete. For a saturated homogenous system, the surface resistance and the uniaxial resistance measurements provide equivalent measures of resistivity once geometry
Yaghoob Farnam, Dale P. Bentz, Aaron R. Sakulich, Daniel R. Flynn, Jason Weiss
Deicing salts are often applied to the surface of pavements and bridge decks in the winter to melt ice; thereby improving safety for the travelling public. In this paper, the influence of NaCl deicing salt on freezing and thawing temperatures of pore
Edward Garboczi, Rolands Cepuritis, Borge Wigum, Ernst Mortsell, Stefan Jacobsen
Characteristics of fine particles (fines, 0 μm to 125 μm) from seven different crushed and natural sands from five different Norwegian rock types were determined. The results suggest that the same water absorption values, as determined by EN 1097-6 on
Robert Spragg, Yiwen Bu, Kenneth A. Snyder, Dale P. Bentz, Jason Weiss
These projects examined the potential for using electrical testing on concrete as a potential surrogate for obtaining information on ion and fluid transport. Electrical measurements are particularly attractive for use in quality control as they are easy to
Ahmed M. Hassan, Edward Garboczi, Robert McMichael, Jack T. Surek, Mark D. Stiles, David F. Plusquellic, Virgil Provenzano, Paul E. Stutzman, Shuangzhen S. Wang, Sung Kim, Michael D. Janezic, Jason Coder, Nicos Martys, David R. Novotny
Some iron oxide corrosion products exhibit antiferromagnetic magnetic resonances (AFMR) at around 100 GHz at normal temperatures. AFMR can be detected in laboratory conditions, which serves as the basis for a new non-destructive spectroscopic method for
Alejandro Duran-Herrera, Jose M. Mendoza-Rangel, Edgar de los Santos Rodriguez, Francisco Vazquez, P Valdez, Dale P. Bentz
In many parts of the world, corrosion of reinforcing steel in concrete induced by carbonation of the concrete continues to be a major durability concern. This paper investigates the accelerated and natural carbonation resistance of a set of 7 concretes
One of the primary approaches being explored to produce more sustainable concretes consists of replacing a significant portion of the portland cement with industrial by-products. In high volume fly ash (HVFA) concretes, for example, the nominal goal is to
Igor de la Varga, Robert Spragg, Carmelo di Bella, Javier Castro, Dale P. Bentz, Jason Weiss
The transport of fluid and ions in concrete mixtures is central to many aspects of concrete deterioration. As a result, transport properties are frequently measured as an indication of the durability that a concrete mixture may be expected to have. This
Robert Spragg, Chiara Villani, Kenneth A. Snyder, Dale P. Bentz, Jeffrey W. Bullard, Jason Weiss
The electrical resistivity of concrete is increasingly measured as an indicator of its fluid transport properties, for use in quality control or for service life prediction. While electrical tests have the advantage of being easy and rapid to perform
Internal curing uses pre-wetted fine lightweight aggregate (LWA) to supply cementitious systems with water. This increases the hydration of cement and reduces the influence of self-desiccation resulting in concrete with increased compressive strength
Portland cement is a fundamental structural and binding material for industry and society. Its structural and physical properties at different scales show a complexity that can presently be barely managed through experimental and computational methods
Tandre Oey, Aditya Kumar, Jeffrey W. Bullard, Narayanan Neithalath, Gaurav Sant
Finely ground mineral powders are known to accelerate cement hydration rates. This "filler effect" has been attributed to the effects of dilution (w/c increase) when the cement content is reduced or to the provision of additional surface area by fine
From its small beginnings back in the 1960s, computational materials science has come a long way. The field is currently getting even more exciting with ideas like integrated computational materials engineering [1] being seriously considered in the start
Xueyu Pang, Dale P. Bentz, Christian Meyer, Gary Funkhouser, Robert Darbe
Two different methods of evaluating cement hydration kinetics, namely chemical shrinkage and isothermal calorimetry tests, are used to investigate the early stage hydration of different classes of oilwell cement at various temperatures. For a given cement
Joseph J. Biernacki, Jeffrey W. Bullard, Constantiner Constantiner, Richard Meininger, Maria Juenger, Josephine H. Cheung, William Hansen, R. D. Hooton, Andreas Luttge, Jeffrey J. Thomas
Hydration of portland cement is the cornerstone of the process responsible for microstructure development in concrete and ultimately controls the kinetics of all materials properties that make concrete such a useful product for society (properties such as
Transportation agencies strive to provide durable, long lasting concrete bridge decks. While high performance concrete is frequently desired due to its resistance to chloride ingress and corrosion, these mixtures are often accompanied with an increased
Concrete can develop tensile stress when it is restrained from shrinking freely. Standard tests, like the restrained ring test (ASTM C1581-09) can be used to quantify how likely a mixture may be to crack under constant temperature conditions. The
Lisa R. Gurney, Dale P. Bentz, Taijiro Sato, Jason Weiss
From a sustainability perspective, high volume fly ash (HVFA) concretes are attractive not only because of the reduction in cement content and its associated greenhouse gases that they provide, but also because they avoid landfilling excessive quantities
There are different ways of mathematically representing 3-D heterogeneous material structures. But for each of these methods, usually the desired end result is a 3-D finite element mesh that will be used to investigate the mechanical properties of the
Edward Garboczi, Dale P. Bentz, Jeffrey M. Davis, Yang Lu
The prediction of the service life of concrete materials is difficult, mainly because of their complex heterogeneous microstructure and their random nature. Studying the presence of cracks in concrete and their effect on chloride transport and reaction