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The transformation of chemical analyses to phase estimates via the Bogue calculations has been successfully used by industry for the past 70 years. Since its inception, however, it has been recognized as an estimate of potential phase composition based
The use of cementitious materials has been proposed in a variety of waste management systems because these materials can have a variety of desirable performance characteristics: hydraulic isolation, chemical isolation, structural stability. Cementitious
While high volume fly ash (HVFA) concrete mixtures are attractive from a sustainability viewpoint, they are sometimes plagued by long delays in finishing, producing a performance that is unacceptable to contractors. In this paper, isothermal calorimetry
This document serves as the users guide for the educational version of the Virtual Cement and Concrete Testing Laboratory (VCCTL) software, version 2.0. Using the VCCTL, a user may create 3D microstructures of cement paste with clinker, calcium sulfate
The research presented here is the first report of fabricating mulitwalled carbon nanotube (MWCNT) based thin coatings on polyurethane foam (PUF) using Layer-by-Layer assembly, and using MWCNTs to reduce the flammability of PUF. The (440.6 ± 47.1) nm thick
The heat of hydration of hydraulic cements results from the complex sets of phase dissolution and precipitation activity accompanying the addition of water to a cement. Heat of hydration is currently measured in one of two ways: 1) through an acid
Christopher C. White, Donald L. Hunston, Sam Williams
A novel sealant-testing device was used to continuously monitor the mechanical properties of a one part silicone sealant for movement cycles initiated from 10 h to 168 h after sample creation. These cure times fall between the proposed RILEM TC 139
A novel sealant-testing device was used to continuously monitor the mechanical properties of a one part silicone sealant for movement cycles initiated from 10 h to 168 h after sample creation. These cure times fall between the proposed RILEM TC139
John Schlitter, Andrew Senter, Dale P. Bentz, Tommy Nantung, Jason Weiss
The standard restrained ring test (ASTM 1581-04) is a simple, economical method to evaluate a concrete mixture s susceptibility of shrinkage cracking. Unfortunately, the test only provides restraint against samples that shrink and can not be used to
Javier Castro, Ryan Henkensiefken, Tommy Nantung, Dale P. Bentz, Jason Weiss
The increased propensity for shrinkage cracking in low water-to-cement ratio (w/c) concrete has resulted in the development of new methods that can reduce the risk of early-age cracking, including internal curing. Internal curing can use water-filled
Dale P. Bentz, Chiara F. Ferraris, Max A. Peltz, John A. Winpigler
High volume fly ash (HVFA) concretes are one component of creating a more sustainable infrastructure. By replacing 50 % or more of the portland cement with fly ash, a significant reduction is achieved in the carbon footprint of the in place concrete. While
Sara Laustsen, Dale P. Bentz, Marianne Hasholt, Ole M. Jensen
This paper describes how X-ray computed tomography (CT) scanning can be used to determine the void distribution in hardened concrete. Three different approaches are used to analyse a binary data set created from CT measurement. One approach classifies a
Jeffrey W. Bullard, Barbara Lothenbach, Paul E. Stutzman, Kenneth A. Snyder
We couple equilibrium thermodynamic calculations to a 3D microstructure model to simulate microstructure development during hydration of portland cement paste. The model uses a collection of growth/dissolution rules to approximate a range of growth modes
Particles of tricalcium silicate in water typically exhibit a relatively quiescent period (called Stage II) shortly after wetting, lasting up to several hours and during which little apparent reaction occurs. Stage II frequently terminates at about the
Milani S. Sumanasooriya, Dale P. Bentz, Narayanan Neithalath
Transport properties of porous materials such as pervious concretes are inherently dependent on a variety of pore structure features. Empirical equations are typically used to relate the pore structure of a porous material to its permeability. In this
Kar T. Tan, Christopher C. White, Donald L. Hunston
Adhesion of spray-applied fire-resistive materials (SFRMs) to steel structures is critical in enabling the capacity of a building to remain functional for a specific length of time during a fire for life safety and fire department assess. Empirical tests
Xiaohong Gu, Guodong Chen, Minhua Zhao, Stephanie S. Watson, Tinh Nguyen, Joannie W. Chin, Jonathan W. Martin
In this study, the role of the nanoparticle/polymer interface in the long-term UV weathering performance of a nano-ZnO filled polyurethane (PU) coating system was investigated. The effects of the parameters that can influence the particle/polymer
Christopher C. White, Kar T. Tan, Donald L. Hunston
Test methods were developed to duplicate the failure modes that occur to sealants during exposure in structures. The methods used a systematic approach to identify independent and synergistic effects of various aging factors on the durability of sealants
Narayanan Neithalath, Dale P. Bentz, Milani S. Sumanasooriya
Pervious concrete is receiving renewed interest as a sustainable construction material for parking lots, sidewalks, and low-traffic-volume roads. A key characteristic of this material is its coarse porosity, achieved by omitting the fine aggregates from a
While high volume fly ash (HVFA) concretes can be designed and produced to meet 28-d strength requirements and often even exceed the durability performance of conventional concretes, a persistent problem is the potentially long delay in setting time that
Mickey Richardson, Eun S. Park, Jaehyun Kim, Gale A. Holmes
A small series of functionalized C60-fullerene/epoxy nanocomposites were prepared, and their respective ultimate tensile strengths were determined. The functionalization route of the fullerenes was performed using the well-known Prato reaction, with
The mechanical ASTM sieve analysis and roundness measurement methods are traditionally used for characterization of the glass beads utilized in traffic markings. In recent years, computerized optical testing of the glass beads has been increasingly used as
Gale A. Holmes, Jae Hyun Kim, Stefan D. Leigh, Walter G. McDonough
The exact theories advanced by Curtin et al. (1991) and Hui, Phoenix, et al. (1995) to describe the fiber break evolution process in single fiber composites were found to be incorrect when compared to experimental data. In contrast to theoretical