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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
Chiara F. Ferraris, Nicos Martys, Myoungsung Choi, Van Bui, Trey Hamilton, Didier Lootens
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
One approach to increasing the sustainability of concrete construction is to replace a significant portion of the ordinary portland cement (OPC) with a supplementary cementitious material, such as fly ash. This paper presents mixture proportions and
Edward Garboczi, Aaron M. Forster, Jan Miller, Chen-Luh Lin, Cesar Chan, Kumar Natesaiyer, David Song, Suman Sinha-Ray
A combined computational/experimental materials science technique was developed for acquiring the structure of a rigid organic foam (ROHACELL) using X-ray computed tomography with appropriate image analysis, computing the elastic moduli using large-scale
Christopher C. White, Kar T. Tan, Donald L. Hunston, Aaron M. Forster, Deborah S. Jacobs
Accelerated and natural aging of safety films used in protective glazing systems was investigated by the use of Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy and tensile tests. Accelerated conditions involved simultaneous
Rick D. Davis, Yu-Chin Li, Michelle R. Gervasio, Yeon S. Kim
In this manuscript, natural materials were combined into a single pot to produce flexible, highly fire resistant, and bioinspired coatings on flexible polyurethane foam (PUF). In one step, PUF was coated with a fire protective layer constructed of a
Li xiodan, Zachary Grasley, Jeffrey W. Bullard, Edward Garboczi
A computational model has been developed that combines finite element methods with microstructure development simulations to quantitatively predict the viscoelastic/viscoplastic relaxation of cement paste due to intrinsic calcium silicate hydrate
Xiaodan Li, Zachary Grasley, Edward Garboczi, Jeffrey W. Bullard
Finite element procedures combined with microstructure development modeling are integrated to quantitatively predict the viscoelastic/viscoplastic relaxation of cement paste due to intrinsic calcium silicate hydrate viscoelasticity and microstructure
A common numerical task is to compute the effective elastic properties of a random composite material based on its microstructure by operating on a 3D digital image of the microstructure obtained via X-ray computed tomography (CT). The 3-D image is usually
Dale P. Bentz, Ahmad Ardani, Tim Barrett, Scott Z. Jones, Didier Lootens, Max A. Peltz, Taijiro Sato, Paul E. Stutzman, Jussara Tanesi, Jason Weiss
Limestone (calcium carbonate) has long been a critical component of concrete, whether as the primary raw material for cement production, a fine powder added to the binder component, or a source of fine and/or coarse aggregate. This paper focuses on the
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
Polymer nanocomposites are increasingly used in outdoor structures. However, polymers are susceptible to degradation by solar ultraviolet (UV) radiation, which potentially releases nanofiller during polymer nanocomposites' life cycle. Such release may pose
The objective of this study was to investigate how the heterogeneity due to nanoparticle dispersion of polymeric coatings affects surface morphological changes during ultraviolet (UV) exposure under different weathering conditions. Three types of nano
The deterioration of stone and brick architecture or sculpture often involves damage caused by moisture. The feasibility of a non-destructive testing (NDT) method based on prompt gamma neutron activation (PGNA) for measuring the element hydrogen as an