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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
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
An analytical full wave model of parallel, randomly dispersed carbon nanotubes (CNTs) embedded in a dielectric slab was developed to calculate the electromagnetic scattering from simple but non-trivial CNT composites. The model focuses on empty and metal
Bulk oxide determinations from two pairs of ASTM C150 portland cements are used to calculate precision and accuracy values for X-ray fluorescence (XRF) by both the fused glass bead and the pressed powder sample preparation methods. The first pair of
Dale P. Bentz, W. S. Guthrie, Scott Z. Jones, Nicos Martys
The prediction of concrete service life is of paramount importance for upgrading our nations built infrastructure. Although computer models for predicting the service life of reinforced concrete exposed to chlorides (e.g., road salts) have been developed
Chiara F. Ferraris, H. R. R. Hamilton, Alexander Piper
This report contains a summary of the research performed to develop a replacement for the high-temperature grout fluidity (HTGF) test. The HTGF test was employed in the past by FDOT to qualify post-tensioning (PT) grouts for use in post-tensioned bridge
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
Nanoparticles are increasingly incorporated in flooring coatings and interior paints to improve their abrasion and microbial resistance. One particular concern of this application is the release of nanoparticles from these surfaces due to repeated
Because ready-mixed concrete is placed under a wide variety of environmental conditions, the influence of temperature on the hydration reactions and the accompanying setting (hardening) process is of critical importance. While contractors are generally
Dale P. Bentz, Kenneth A. Snyder, Amzaray M. Ahmed
One common concern limiting the proliferation of high-volume fly ash (HVFA) concrete mixtures is the significant delay in setting that is sometimes encountered in field concrete mixtures. While several methods to mitigate the delayed setting times of HVFA
The Bogue calculations of cement composition are used for manufacturing process control and cement classification. While it is commonly understood that the Bogue calculations are estimates with potential intrinsic biases, the magnitudes of such biases are
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
Chun-Chieh Tien, Ching-Hsuan Chang, Bernard Hao-Chih Liu, Deborah Jacobs, Savelas A. Rabb, Lee L. Yu, Tinh Nguyen, Li Piin Sung
Polymer nanocoatings are increasingly used outdoors and in harsh environments. However, because most common polymers degraded by the weathering elements, nanoparticles in polymer nanocoatings may be released into the environments. Such nanoparticle release