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Edward J. Garboczi, Kenneth A. Snyder, Rolands Cepuritis, Stefan Jacobsen
The shape of concrete aggregate fines, with particle sizes between 3 µm and 250 µm, produced by high-speed vertical shaft impact (VSI) crushing of 10 different rock types from quarries in Norway, has been studied by both dynamic image analysis (DIA), which
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
Tinh Nguyen, Elijah J. Petersen, Bastien T. Pellegrin, Justin M. Gorham, Thomas F. Lam, Minhua Zhao, Li Piin Sung
Carbon nanotubes (CNTs) are increasingly used in consumer and structural polymeric products to enhance a variety of properties. Under weathering, the polymer matrix will degrade and the nanofillers will potentially be released from the products, which
Dale P. Bentz, Chiara F. Ferraris, Scott Z. Jones, Didier Lootens, Franco Zunino
Developing functional concrete mixtures with less ordinary portland cement (OPC) has been one of the key objectives of the 21st century sustainability movement. While the supply of many alternatives to OPC (such as fly ash or slag) may be limited, those of
Edward J. Garboczi, Chiara F. Ferraris, Rolands Cepuritis, Stefan Jacobsen, Bjorn Sorensen
The study investigates which measurement methods are best applicable to crushed concrete aggregate fines smaller than about 250 µm to determine particle size distribution (PSD) and specific surface area: wet-method laser diffraction (LD), X-ray
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
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
Mauro Zammarano, Shonali Nazare, John R. Shields, Kathleen M. Hoffman, Rick D. Davis
A durable and flexible silicone-based backcoating (halogen and formaldehyde free) is applied to the backside of an otherwise smoldering-prone and flammable fabric. When exposed to fire, cyclic siloxanes (produced by thermal decomposition of the backcoating
Cold weather concreting often requires the use of chemical accelerators to speed up the hydration reactions of the cement, so that setting and early-age strength development will occur in a timely manner. While calcium chloride (dihydrate CaCl2∙2H2O) is
To compute light scattering or any other quantity for a random particle, one needs to mathematically know the shape of the particle. For regular particles like spheres and ellipsoids, this is straightforward to do. For random particles, with realistic
Alex Olivas, Chiara C. Ferraris, Brian Lang, Jennifer Richter, Raissa Ferron
Cement-based materials (e.g. cement paste, mortar and concrete) are complex rheological fluids that display time-dependent and shear-dependent rheological behavior. Over the years, various concrete rheometers have been proposed and made available
Richard A Livingston, Carol A. Grissom, Edward Vicenzi, Zoe Weldon-Yochim, Nicole Little, Janet Douglas, Alexandre Fowler, Cara Santelli, Dorothea Macholdt, Diana Ortiz-Montalvo, Stephanie S. Watson
Bluish black, highly adherent patches have been observed growing on the Seneca sandstone of the Smithsonian Castle in Washington, DC. They are significantly enriched in Mn compared to the underlying sandstone, by a factor of 100, which suggests that