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Catherine Lucero, Dale P. Bentz, Daniel S. Hussey, David L. Jacobson, Jason Weiss
Air entrainment is commonly added to concrete to help in reducing the potential for freeze thaw damage. It is hypothesized that the entrained air voids remain unsaturated or partially saturated long after the smaller pores fill with water. Small gel and
Christopher C. White, Donald L. Hunston, Kar T. Tan
The toughness of polymer and glass laminates or win-dow glazing, are used to protect buildings and occupants from shattered glass resulting from natural disasters (e.g., hurricanes, tornadoes, seismic events), and intentional events (e.g., robbery
Myoungsung Choi, Chiara C. Ferraris, Nicos Martys, Didier Lootens, Van Bui, Trey Hamilton
With the increasing use of pumping to place concrete, the development and refinement of the industry practice to ensure successful concrete pumping is becoming an important need for the concrete construction industry. To date, research on concrete pumping
Yaghoob Farnam, Andrew Wiese, Dale P. Bentz, Jeffrey M. Davis, Jason Weiss
MgCl2 is used in deicing applications due to its capability to depress freezing temperatures to a lower point than other salts like NaCl. The constituents of concrete (i.e., pores solution, calcium hydroxide, aluminate phases, and calcium silicate hydrate
Yaghoob Farnam, Hadi S. Esmaeeli, Dale P. Bentz, Pablo Zavattieri, Jason Weiss
In North America, some concrete pavements and sidewalks have shown severe damage during freezing. Research has been performed to better understand the cause of damage. A test method (called longitudinal guarded comparative calorimeter (LGCC)) has been
X-ray powder diffraction analysis is used in the cement industry as a direct analytical method for phase identification and quantitative analysis of clinker and cements. Quantitative methods initially relied on the development of calibration curves
Existing concrete microstructural models of particles embedded in matrix materials are only represented by regular shape particles like spheres, ellipsoids, or multi-faceted polyhedrons. However, the real particle shapes are more complex and sometimes play
Christopher C. White, Kar T. Tan, Donald L. Hunston, Walter E. Byrd
Effective fire protection of steel can be fully realized when spray-applied fire resistive materials (SFRMs) are bonded sufficiently to structural steel during the event of fire. The adhesion mechanisms and characterization at elevated temperatures
Christopher C. White, Kar T. Tan, Donald L. Hunston, Kristen L. Steffens, Deborah S. Jacobs, Bulent Akgun, Vogt D. Bryan
Moisture attack on adhesive joints is a long-standing scientific and engineering problem. A particularly interesting observation is that when the moisture level in certain systems exceeds a critical concentration, the bonded joint shows a dramatic loss of
Christopher C. White, Kar T. Tan, Donald L. Hunston, Adam L. Pintar, James J. Filliben
An empirically-based model has been created to predict the change in modulus for a sealant exposed to outdoor weathering. The underlying high precision data supporting this model was obtained using the NIST SPHERE (Simulated Photo degradation by High
Construction aggregate particles, fine or coarse, can be mathematically characterized using spherical harmonic series and used to simulate random parking of irregular aggregates to form a virtual mortar or concrete using the Anm model. Any other similar
Yaghoob Farnam, M R. Geiker, Dale P. Bentz, Jason Weiss
Different constituents of concrete can have cracking behavior that varies in terms of the acoustic waveform that is generated. Understanding the waveform may provide insight into the source and behavior of a crack that occurs in a cementitious composite
William Ha, Dale P. Bentz, Wyatt Kahler, Laurence Walsh
Introduction: The setting times of commercial mineral trioxide aggregate (MTA) and Portland cements vary. It was hypothesized that much of this variation was due to differences in particle size distribution. Methods: Two gram samples from 11 MTA-type