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Characterization and Performance of Zero-Cement Concrete

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Characterization and Performance of Zero-Cement Concrete CHARACTERIZATION AND PERFORMANCE OF ZERO-CEMENT CONCRETE December 2018 MoDOT Research Report number cmr 18-011 Final Report Project number TR201614 PREPARED BY: Eslam Gomaa Simon Sargon Cedric Kashosi Ahmed Gheni Mohamed ElGawady, Ph.D. William Schonberg, Ph.D., PE Missouri University of Science and Technology PREPARED FOR: Missouri Department of Transportation Construction and Materials Division Research Section TECHNICAL REPORT DOCUMENTATION PAGE 1. Report No. 2. Government Accession No. 3. Recipient’s Catalog No. cmr 18-011 4. Title and Subtitle 5. Report Date Characterization and Performance of Zero-Cement Concrete May 2018 Published: December 2018 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. Eslam Gomaa https://orcid.org/0000-0002-8748-8867 Simon Sargon Cedric Kashosi Ahmed Gheni https://orcid.org/0000-0001-9042-869X Mohamed ElGawady, Ph.D. https://orcid.org/0000-0001-6928-9875 William Schonberg, Ph.D, PE https://orcid.org/0000-0002-6405-349X 9. Performing Organization Name and Address 10. Work Unit No. Department of Civil, Architectural and Environmental Engineering Missouri University of Science and Technology 11. Contract or Grant No. 1401 N. Pine St., Rolla, MO 65409 MoDOT project # TR201614 12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered Missouri Department of Transportation (SPR) Final Report (January 2017-April 2018) Construction and Materials Division 14. Sponsoring Agency Code P.O. Box 270 Jefferson City, MO 65102 15. Supplementary Notes Conducted in cooperation with the U.S. Department of Transportation, Federal Highway Administration. MoDOT research reports are available in the Innovation Library at https://www.modot.org/research-publications. 16. Abstract This study has investigated the feasibility of using five different types of class C fly ashes (FAs) sourced from Labadie, Jeffrey, Kansas City, Thomas Hill, and Sikeston power plants in the state of Missouri to synthesize zero-cement concrete (ZCC) for different structural and repair applications. Alkali activator (Alk) consisting of sodium silicate (SS), Na2SiO3, and sodium hydroxide (SH), NaOH were used to synthesize the ZCC. Slag, crumb rubber, and air-entraining admixture (AEA) were used in a few mixtures as additives to improve the durability of the ZCC. Approximately 300 mortar and concrete mixtures were prepared during this study to investigate the mixing procedure, water/FA, Alk/FA, SS/SH, curing regime, fresh properties, mechanical properties, durability, repair applicability, and cost analysis of the ZCC. A 5000 psi MoDOT conventional concrete (CC) mixture was also prepared and tested for comparison purposes. This study revealed that ZCC can be used as a replacement for CC. ZCC showed good workability and adequate compressive strength for structural applications ranging from 3,660 psi to 7,465 psi based on the curing regime and source of FA. Some ZCC mixtures successfully passed 300 cycles of freeze and thaw per ASTM C666-15 procedures A and B. Furthermore, the drying shrinkage values of the ZCC specimens at all ages were significantly lower than those of the corresponding CC specimens. ZCC also presents higher corrosion resistance compared to CC. ZCC mixtures have a low to moderate permeability and chloride ion penetrability, while the CC mixture showed a high permeability and chloride ion penetrability. Finally, ZCC can be used as a repair material for existing concrete structures. The bond between ZCC as a repair material and CC as a host material was adequate and comparable to the bond between CC and CC. 17. Key Words 18. Distribution Statement Admixtures; Binders; Bridge decks; Concrete; Fly ash; Girders; No restrictions. This document is available through the Hydration; Portland cement National Technical Information Service, Springfield, VA 22161. 19. Security Classif. (of this report) 20. Security Classif. (of this 21. No. of Pages 22. Price Unclassified. page) 327 Unclassified. Form DOT F 1700.7 (8-72) Reproduction of completed page authorized FINAL REPORT Characterization and Performance of Zero-Cement Concrete Prepared for Missouri Department of Transportation By Eslam Gomaa Simon Sargon Cedric Kashosi Ahmed Gheni Mohamed ElGawady, Ph.D. William Schonberg, Ph.D, PE Missouri University of Science and Technology, Rolla, Missouri May 2018 COPYRIGHT STATEMENT Authors herein are responsible for the authenticity of their materials and for obtaining written permissions from publishers or individuals who own the copyright to any previously published or copyrighted material used herein. DISCLAIMER STATEMENT The opinions, findings, and conclusions expressed in this document are those of the investigators. They are not necessarily those of the Missouri Department of Transportation, U.S. Department of Transportation, or Federal Highway Administration. This information does not constitute a standard or specification i ACKNOWLEDGMENTS The authors would like to acknowledge all the organizations and individuals that supported this research project. The work in this research project was funded by Missouri Department of Transportation (MoDOT). Partial financial supported from Ameren Corporation is also appreciated. Special thanks for the Construction and Materials Laboratory of MoDOT for testing the ZCC prisms under the freeze and thaw cycles per ASTM C666-15 Procedure B. Appreciation is also extended to Mr. Brett Trautman the director of the Physical Laboratory at the Construction and Materials Division. A sincere thank you to Ms. Lucille Goff the supervisor of the Materials Testing, Construction and Materials, Central Laboratory. The authors also wish to extend a sincere thank you to Mr. Tom Crowe the intermediate Material Technician, Construction and Materials, Central Laboratory. Appreciation is extended to Michael Tierney and Randy Blalock from MoDOT for their technical support during the durability test. The authors would like also to thank Headwater Resources and Ameren for donating the different fly ashes used in this study over the project period. Appreciation extended to PQ Corporation for supplying the sodium silicate with a special discount. The authors also wish to extend a sincere thank you to Clinton Knox, the Operations Supervisor, Boral CM Services for his great help with supplying the fly ashes sourced from Sikeston, Thomas Hill and Jeffrey Energy Center. Special thanks for John Bullock and Ronald Lekrone for their great help in collecting the fly ashes from Labadie and Kansas City and appreciated technical support. The authors highly appreciate Dr. Mike Lusher, Jason Cox, Gary L. Abbott, and Brian Swift for their valuable technical support. Finally, the authors would like to express their appreciation to the many graduate and undergraduate students that contributed to the project including Ikram Efaz, Yasser Darwish, Matthew Short, Kritsada Cody, Jonathan Cureton, Royce Ingram, Zoe Rechav, Luke Myrick, Emily Eisenbacher, and Brittney Kennedy. ii EXECUTIVE SUMMARY This study has investigated the feasibility of using locally available fly ashes (FAs) to synthesize zero-cement concrete (ZCC) for different structural and repair applications. Using ZCC made of 100% FA reduces global CO2 emissions, saves energy, and decreases raw material consumption during the production process of ordinary Portland cement. Class C FAs, sourced from Labadie, Jeffrey, Kansas City, Thomas Hill, and Sikeston power plants in the state of Missouri, were used to synthesize the ZCC. Two different alkali activators (Alk) were used in this study: sodium silicate (SS), Na2SiO3, and sodium hydroxide (SH), NaOH. Slag, crumb rubber, and air- entraining admixture (AEA) were used in a few mixtures as additives to improve the durability of the ZCC. The mixing procedure, water/FA, Alk/FA, SS/SH, curing regime, fresh properties, mechanical properties, durability, repair applicability, and cost analysis of the ZCC were investigated in this study. Approximately 300 mortar and concrete mixtures were tested. A 5000 psi MoDOT conventional concrete (CC) mixture was prepared and tested for comparison purposes. Three curing regimes (oven, ambient, and moist) were applied to the ZCC. This study revealed that ZCC can be used as a replacement for CC. ZCC showed good workability and adequate compressive strength for structural applications ranging from 3,660 psi to 7,465 psi based on the curing regime and source of FA. Some ZCC mixtures successfully passed 300 cycles of freeze and thaw per ASTM C666-15 procedures A and B. Furthermore, the drying shrinkage values of the ZCC specimens at all ages were significantly lower than those of the CC specimens. ZCC also presents higher corrosion resistance compared to CC. ZCC mixtures have a low to moderate permeability and chloride ion penetrability, while the CC mixture showed a high permeability and chloride ion penetrability. Finally, ZCC can be used as a repair material for existing concrete structures. The bond between ZCC as a repair material and CC as a host material was adequate and comparable to the bond between CC and CC. The relationships between the compressive strength of ZCC and splitting tensile strength, flexural strength, and modulus of elasticity are similar to those used by current codes and standards such ACI 318-14. Finally, ZCC is cost competitive; the cost of ZCC ranged from $59/yd3 to $105/yd3. iii Table of Contents Chapter 1: Introduction ..............................................................................................................
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