Estimation of the degree of hydration of blended cement pastes by a scanning electron microscope point-counting procedure X Feng, E J Garboczi, D P Bentz, P E Stutzman, Thomas O Mason Materials Science and Engineering
The NIST-Industry Virtual Cement and Concrete Testing Laboratory (VCCTL) Consortium has developed an integrated software package for performing simulations of a number of engineering test measurements, including isothermal calorimetry, adiabatic temperature change, chemical shrinkage, elastic moduli, and compressive strength
May 05, 2010· One source of untapped potential for varying engineering properties of hardened concrete is the variation of the cement particle size distribution In this study, the performance of cements prepared by blending a coarse ASTM C150 type I/II and a fine type III cement obtained from the same clinker in three different proportions is examined
The Visible Cement Data Set website has been created and is currently being populated with the various data sets collected during the experiments conducted at the ESRF faciliti The three-dimensional data sets available from the site are presently unique in the world due to their high spatial resolution (voxel size less than one micrometer)
Dr Feng is involved in both specialized and standard testing of cement, fly ash, slag, metakaolin, CKD, aggregate, mortar, and concrete She also performs analysis and evaluation of cement and concrete by X-ray Diffraction, investigation of alkali-silica reaction (ASR) and delayed ettringite formation in concrete structures, research on test methods for water-soluble sulfate in soils, and .
Computer simulation of impedance spectroscopy (IS) of hydrating cement paste, using a three-dimensional, four-phase model, is described Two puzzling features of experimental IS results, the possible offset resistance in the Nyquist plot and the sharp decrease in normalized conductivity within the first 50 h of reaction, have been studied using the computer simulation model
Bentz, DP, "Cement Hydration: Building Bridges and Dams at the Microstructure Level," Proceedings of the Knud Hojgaard Conference on Advanced Cement-Based Materials: Research and Testing Eds OM Jensen, M Geiker, and H Stang, 135-146 (2006) and Materials and Structures, 40 ,
Dale P Bentz: National Institute of Standards and Technology: ACEM20170126: Relating the Electrical Resistance of Fresh Concrete to Mixture Proportions: D P Bentz: NIST: 05 March 2018: STP12645S: SEM Analysis and Computer Modelling of Hydration of Portland Cement Particles: Dale P Bentz: National Institute of Standards and Technology: 01 .
A digital image-based model of the microstructure of cement paste, coupled with exact transport algorithms, is used to study the diffusivity of Portland cement paste The principal variabl
Experimental and Computer Simulation Results for the Electrical Conductivity of Portland Cement Paste - Volume 245 - BJ Christensen, TO Mason, HM Jennings, DP .
286 DP Bentz/Cement & Concrete Composites 31 (2009) 285–289 schematically in two dimensions in Fig 2 The impetus for the cur-rent study was an observation made during a recent study on the effectiveness of viscosity modiﬁers in reducing the ingress of chlo-
D P Bentz National Institute of Standards and Technology Gaithersburg, MD 20899 Early-Age Cracking Review: Mechanisms, Material Properties, and Mitigation Strategies III-2 , and concrete that contribute to the occurrence of early-age cracking, and mixture proportioning and
Chapter 3 Cement and concrete characterization This chapter discusses cement and concrete characterization It covers both microscopy of various kinds (scanning electron and optical) and x-ray diffraction analysis Images of cement and concrete microstructure are important in their own right, for analysis and characterization
According to unpublished work from Bentz the figures are 25% for needle like products and 30% for plate like products See also Garboczi, E J and D P Bentz (1996) The Historical Record The historical record is entirely consistent with everything we say about successfully formulating a carbonating cement like Eco-Cement
Jul 14, 2018·  Bentz, D P Influence of water-to-cement ratio on hydration kinetics: simple models based on spatial considerations Cement and Concrete Research Cement and Concrete Research 36
suggested curing the concrete only until this discontinuity is achieved, as further “saturated” curing would result in little if any further water flow into the concrete3 Based on a microstructural model for cement paste hydration, Bentz and Garboczi suggested a critical capillary porosity threshold value of ,
mortars and concretes DP Bentz1, MA Peltz1, A Dura´n-Herrera2, P Valdez2 and CA Jua´rez2 Abstract As sustainability moves to the forefront of construction, the utilization of high-volume fly ash concrete mixtures to reduce CO 2 emissions and cement , DP Bentz, Building and Fire Research Laboratory, National Institute of Standards and .
CiteSeerX - Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda): Suspended hydration and loss of freezable water in cement pastes exposed to 90 % relative humidity by
Sep 14, 2016· By Reid W Castrodale, PhD, PE I nternal curing is rapidly emerging as an effective way to improve curing of concrete It holds promise for producing concrete with increased compressive strength and reduced permeability and cracking, attributes that lengthen the service life of infrastructure products such as bridge decks
Jan 26, 2017· and Mass Concrete) procedures, w/c was varied only by changing the cement content (c) while keeping the water content constant This ensured that the electrical resistivity increased with an increase in w/c, as for a higher w/c (lower cement content), there were fewer conductive ions being released by the reduced quantity of cement (per unit volume
7 Transport and Elastic Properties of Mortar and Concrete Share Facebook Google Plus Twitter This chapter covers the transport properties of mortar and concrete, starting with the basic hard core soft shell microstructure model, and then building up to the full multi-scale diffusivity model , DP Bentz, Cement and Concrete Research 30 .
Evaluation of sustainable high-volume ﬂy ash concretes A Durán-Herreraa,⇑, CA Juáreza, P Valdeza, DP Bentza,b a Academic Group on Concrete Technology, Facultad de Ingeniería Civil, Center on Innovation, Research and Development in Engineering and Technology (CIIDIT), Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL 66450, Mexico
What is “Sustainable” About Using ESCS for Internal Curing? Sustainability has become a major focus of the building industry as well as society in general In addressing the sustainability issue, an essential step is evaluating how a given product interfaces with adjacent products and what affect this has on the performance of the combined material ,
SH Kosmatka, B Kerkhoff, and WC Panarese, Design and Control of Concrete Mixtures, Portland Cement Association, Skokie, IL 14th Ed, 2002 HFW Taylor, Cement .
cement as a part of the cement content of the binder, while the 5% calcium hydroxide (CH) addition was made on a total solids basis and the 50:50 ratio of ﬂy ash: cement was then computed based on the remaining mass of solids (380 g) For the Class C ﬂy ash mix-tures, previous efforts had indicated that a 2% addition of calcium
Remond, S, Pimienta, P, and Bentz, D P (2002) Effect of the incorporation of municipal solid waste fly ash in cement paste and Mortars Journal of cement and concrete research, 10:12-14
The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts
Bentz, D P, ‘Guide to using CEMHYD3D: A three-dimensional cement hydration and microstructure development modelling package’, NISTIR 5977, US Dept of Commerce, February 1997, software and manual available over the Internet from anonymous ftp at edselcbtnistgov (1296104138) in the /pub/CEMHYD3D subdirectory Google Scholar
To explore the hydration process of fly ash-cement blended mixtures, the degrees of the fly ash and cement reactions as well as the content of nonevaporated water were determined at various water to binder ratios, curing ages, and fly ash incorporation amounts An equation describing the relationship between the degree of hydration and the effective water to binder ratio was established based .
M Pathirage, DP Bentz, G Di Luzio, E Masoero, G Cusatis Pages 36-48 Download PDF , select article Creep model of concrete with recycled coarse and fine aggregates that accounts for creep development trend difference between recycled and natural aggregate concrete