1、An ACI Technical Publication SYMPOSIUM VOLUMESP-312Novel Characterization Techniques and Advanced Cementitious Materials: Tribute to James J. BeaudoinEditors:Mohammad Pour-Ghaz, Aali R. Alizadeh, and Jason Weiss Novel Characterization Techniques and Advanced Cementitious Materials: Tribute to James
2、J. BeaudoinSP-312Editors:Mohammad Pour-Ghaz, Aali R. Alizadeh, and Jason Weiss Discussion is welcomed for all materials published in this issue and will appear ten months from this journals date if the discussion is received within four months of the papers print publication. Discussion of material
3、received after specified dates will be considered individually for publication or private response. ACI Standards published in ACI Journals for public comment have discussion due dates printed with the Standard.The Institute is not responsible for the statements or opinions expressed in its publicat
4、ions. Institute publications are not able to, nor intended to, supplant individual training, responsibility, or judgment of the user, or the supplier, of the information presented.The papers in this volume have been reviewed under Institute publication procedures by individuals expert in the subject
5、 areas of the papers.Copyright 2016AMERICAN CONCRETE INSTITUTE38800 Country Club Dr.Farmington Hills, Michigan 48331All rights reserved, including rights of reproduction and use in any form or by any means, including the making of copies by any photo process, or by any electronic or mechanical devic
6、e, printed or written or oral, or recording for sound or visual reproduction or for use in any knowledge or retrieval system or device, unless permission in writing is obtained from the copyright proprietors.Printed in the United States of AmericaEditorial production: Aimee KahaianISBN-13: 978-1-945
7、487-34-7First printing, October 2016PrefaceWith the recent quest for developing sustainable infrastructure materials, there is a need for more advanced material characterization techniques at different length scales that can provide insight to the nature and fundamental behavior of the new classes o
8、f cementitious materials as they are becoming available. These methods can be used to predict the mechanical properties, microstructural aspects, and long-term performance of different cementitious systems. Examples of these novel techniques that have been recently used for material characterization
9、 include nuclear magnetic resonance spectroscopy, nano- and micro-indentation, X-Ray tomography, and atomic force microscopy. Recently, major progress has also been made in the development of novel cement-based systems such as C-S-H/polymer nanocomposites and self-healing materials. This Special Pub
10、lication aims at providing a treatise on the current research in the areas related to innovative characterization methods and analytical techniques used in the cement and concrete research, as well as the development of novel basic and composite cementitious materials. This Special Publication is de
11、veloped to honor the significant contributions made by Dr. James J. Beaudoin over the past four decades to the advancement of cement and concrete science. Dr. Beaudoin, a Researcher Emeritus, Fellow of the Royal Society of Canada, and Fellow of the American Ceramic Society, has authored more than 50
12、0 publications, including five books, 20 book chapters, encyclopedia contributions, more than 270 research journal papers, 17 patents, and numerous discussions and book reviews. He is the recipient of numerous prestigious awards, including the Della Roy Lecture Award on applications of nanotechnolog
13、y in cement science (American Ceramic Society, 2005), the Wason Medal for Materials Research (American Concrete Institute, March 1999) and the Copeland Award (American Ceramic Society, 1998). The papers included in this Special Publication were presented in two sessions in ACI Fall 2014 Convention,
14、Oct 26-30, 2014. EditorsMohammad Pour-Ghaz, Aali R. Alizadeh, and Jason WeissTABLE OF CONTENTSSP-3121Evaluation of an Accelerated Characterization Method for 1. Pozzolanic ReactivityAuthors: Saamiya Seraj, Maria C.G. JuengerSP-3122A Numerical Study of Polarization Tests Applied to Corrosion in 2. Re
15、inforced ConcreteAuthors: J. Marchand, S. Laurens, Y. Protire, E. SamsonSP-3123Three Dimensional Electrical Imaging of Moisture Ingress in Mortar 3.Authors: Danny Smyl, Milad Hallaji, Aku Seppnen and Mohammad Pour-GhazSP-3124Analysis of Drying Processes in Mortars with and without .4. Shrinkage Redu
16、cing AdmixturesAuthors: C. Villani, C. Lucero, D. Bentz, D. Hussey, D.L. Jacobson and W. J. WeissSP-3125A Critical Look at Advanced Nano-To-Macro Scale Characterization .5. Techniques to Study Passivity and Corrosion of Steel in ConcreteAuthors: Pouria Ghods and O. Burkan IsgorSP-312629Si NMR Invest
17、igations on Alkali Activated Fly Ash or Slag: .6. The Role of The Alkali CationAuthors: Akash Dakhane, Zihui Peng, Robert Marzke, and Narayanan NeithalathSP-3127Hydration of Cement Systems in the Presence of 7. Novel LDH NanocompositesAuthors: Laila Raki and Aali R. AlizadehSP-3128Correlating Micros
18、tructural Features, Elastic, and 8. Viscoelastic Characteristics of Synthetic C-S-HAuthors: S. H. Aboubakr, M. L. Begaye, E. Soliman and M. M. Reda TahaSP-3129Alkali Silica Reaction in Mortar at Room Temperature 9.Authors: Qiang Li, R. James Kirkpatrick, Leslie J. StrubleSP-31210Dynamic and Quasi-St
19、atic Nanoindentation of C-S-H and C-A-S-H .10.Authors: William Hunnicutt, Paramita Mondal, and Leslie StrubleSP-31201 1.1 EVALUATION OF AN ACCELERATED CHARACTERIZATION METHOD FOR POZZOLANIC REACTIVITY Saamiya Seraj, Maria C.G. Juenger The University of Texas at Austin Synopsis: Concerns about the fu
20、ture availability of traditional supplementary cementitious material (SCM) sources, like fly ash, have prompted the search for a wider variety of materials that could be used as SCMs in concrete. An important criterion for an SCM is pozzolanic reactivity, which is its ability to react with calcium h
21、ydroxide in the presence of water to form calcium silicate hydrate (C-S-H). ASTM criteria for SCMs address pozzolanic reactivity indirectly by measuring the compressive strength of SCM containing mortars, or more specifically the strength activity index (SAI). More direct methods of assessing pozzol
22、anic reactivity include measuring the reduction of calcium hydroxide (CH) in cementitious pastes through methods like thermal gravimetric analysis (TGA). However, both direct and indirect tests to evaluate pozzolanic reactivity take a considerable amount of time due to the slow nature of certain poz
23、zolanic reactions. Alternatively, the Chapelle test, which measures the amount of CH fixed by the SCM in solution at high temperatures, can serve as an accelerated test method for screening out potential SCMs. In this paper, the accuracy of the Chapelle test for measuring pozzolanic reactivity is ev
24、aluated for a variety of SCMs with different physical and chemical characteristics by comparing it with more traditional test methods like SAI and CH measurement through TGA. Keywords: Chapelle Test, Concrete, Pozzolans, Reactivity, SCMs Saamiya Seraj and Maria C.G. Juenger 1.2 AUTHOR BIOGRAPHY: Saa
25、miya Seraj received her Ph.D. from the University of Texas at Austin in 2014. Her Ph.D. research was focused on natural pozzolans, which included evaluating the effect of these materials on concrete strength, durability and mixture workability, as well as understanding the hydration chemistry of the
26、 natural pozzolans in cementitious systems. Maria C.G. Juenger is a professor in the Department of Civil, Architectural, and Environmental Engineering at the University of Texas at Austin. Her teaching and research focus on materials used in civil engineering applications. Trained as a chemist and m
27、aterials scientist, she primarily examines chemical issues in cement-based materials. These include: hydration chemistry of portland cement and supplementary cementitious materials; the development of microstructure in cementitious systems; and chemical deterioration processes in concrete. Evaluatio
28、n of an Accelerated Characterization Method for Pozzolanic Reactivity 1.3 1.0 INTRODUCTION Supplementary cementitious materials (SCMs) are very important to the concrete industry due to the benefits they provide in terms of sustainability, economy, and long-term concrete durability. According to AST
29、M International, SCMs are inorganic materials that can contribute to the properties of cementitious mixtures through hydraulic and/or pozzolanic activity (ASTM C 125, 2014). As such they are often used as a partial cement replacement in concrete. Some of the traditional SCMs, like fly ash, are indus
30、trial by-products, which make them cheaper and more sustainable to use in concrete mixtures than ordinary portland cement, whose worldwide production is responsible for 5% of the global anthropogenic CO2 emissions (Humphreys and Mahasenan, 2002). However, due to existing and evolving environmental r
31、egulations (EPA, 2014a-c; Heidrich et al., 2013; Sear, 2009; Barnes and Sear, 2006), there has been a considerable amount of concern regarding the future availability of traditional SCM sources like fly ash. This has prompted the search for alternative materials that could replace traditional SCMs i
32、n concrete and provide similar strength and durability benefits. One of the most important criteria when qualifying new materials as SCMs is to look at their pozzolanic reactivity, which is their ability to react with calcium hydroxide (CH) in the presence of water to form calcium silicate hydrate (
33、C-S-H). Understanding the pozzolanic reactivity is crucial as it gives an indication of the strength and durability benefits that can be derived from the use of the SCMs. ASTM C 618, the standard specification for fly ash and natural pozzolans, measures pozzolanic reactivity indirectly by looking at
34、 strength activity index (SAI), which is the ratio of compressive strength between the SCM containing mortar and the control mortar with no SCMs (ASTM C 618, 2012a; ASTM C 311, 2011b). More direct methods of assessing pozzolanic reactivity include measuring the reduction of calcium hydroxide in ceme
35、ntitious pastes over time through quantitative x-ray diffraction (XRD), thermal gravimetric analysis (TGA) and chemical titration methods like the Frattini test (Tironi et al., 2013; Donatello et al., 2010). However, both direct and indirect tests to evaluate pozzolanic reactivity take a considerabl
36、e amount of time (7 28 d) due to the slow nature of pozzolanic reactions in cementitious pastes. Although there are faster tests that evaluate pozzolanic reactivity by measuring electrical conductivity of solutions containing pozzolans and lime, previous literature has shown these tests to be unreli
37、able. A detailed review of the problems associated with electrical conductivity tests can be found in a journal article by Velazquez et al. (2014). The Chapelle test, which is the focus of the current paper, is a quick test from the French standard, NF P 18-513, Annexe A (2010), designed to measure
38、the pozzolanic reactivity of metakaolin. The Chapelle test accelerates the pozzolanic reaction by using high temperatures, and measures the amount of calcium hydroxide that can be fixed (consumed) by the SCM in a saturated lime solution during a 16 h time period. Although the Chapelle test has been
39、used in previous literature to measure the pozzolanic reactivity of metakaolin, zeolites and fly ashes (Paiva et al., 2012; Taylor-Lange et al., 2012; Ninov et al., 2011; Perraki et al., 2005; Antiohos et al., 2005; Kostuch et al., 1993), very little research has been conducted to evaluate the accur
40、acy of the Chapelle test to predict pozzolanic potential. As such, the current study has compared the results of Chapelle testing on different SCMs to values derived from more traditional methods of evaluating pozzolanic reactivity like SAI and TGA. Since the Chapelle test is conducted at elevated t
41、emperatures for a non-cementitious system, comparing the results to other test methods, which are performed at ambient temperatures for a cementitious system, can give valuable insight as to whether the Chapelle test can reliably predict the pozzolanic performance of an SCM in concrete. Furthermore,
42、 since the Chapelle test was originally designed for metakaolin, a variety of SCMs have been used in the current research to observe whether the test can be reliably used for a range of materials with different physical and chemical characteristics. 2.0 MATERIALS AND METHODS 2.1 Materials In the cur
43、rent study, the pozzolanic reactivity of 11 different SCMs was tested. The SCMs were sourced in the US from Texas, Idaho and Nevada. The 11 SCMs represent a broad range of physical and chemical characteristics, and consist of three pumices, three zeolites, expanded perlite, vitric ash, metakaolin, c
44、alcined shale and fly ash. The X-ray fluorescence (XRF) oxide compositions of the SCMs are presented in Table 1 and were analyzed according to ASTM Saamiya Seraj and Maria C.G. Juenger 1.4 D 4326 (2011). The particle size distributions of the SCMs were also measured to observe whether the Chapelle t
45、est was sensitive to differences in particle size, when the chemical composition of the SCMs was identical. The particle size distributions of the SCMs were analyzed using a laser scattering particle size distribution analyzer and are presented in Figure 1. Along with the SCMs, inert quartz filler w
46、as also evaluated in the Chapelle test to observe the resulting CH fixed values produced by the test when a non-reactive material was tested. One cement was used for all the mixtures and it was an ASTM C 150 (2011) Type I portland cement sourced in Texas, USA. The sand used for all mortar mixtures w
47、as standard graded sand from Ottawa, Illinois, which met all the requirements of ASTM C 778 (2012). The calcium oxide (CaO) used in the Chapelle test was analysis grade, with a purity of 97%. Before testing, the CaO is heated to a temperature of 900C to ensure that calcium hydroxide and calcium carb
48、onate is not present. The CaO is then stored in the desiccator until tested. The sucrose used in the Chapelle test was of 99.7% purity. 2.2 Chapelle Test According to the instructions in NF P 18-513, Annexe A (2010), for the Chapelle test, 1 g (0.002 lb) of pozzolan, 2 g of (0.004 lb) CaO and 250 ml
49、 (0.066 gal) of deionized water were combined in a flask and stirred for 16 h at 85C (185F), using a stirring-heating pad. A blank test, without any SCM was also run. After 16 h, the solution was cooled to ambient temperature (23C (73F) within 15 min, using a combination of running water and ice bath. Immediately after cooling, 60 g (0.13 lbs) of sucrose (in 250 ml (0.066 gal) of water) was added to the solution and stirred for 15 min. 200 ml (0.05 gallons) of the solution was then filtered using a P2 grade filter paper (1-5 m (0.00004-0.0002 in). Five drops of 0.1%
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