Effects of Rebar Temperature and Water to Cement Ratio On
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Assessment of Wood-Based Fly Ash As Alternative Cement Replacement
sustainability Article Assessment of Wood-Based Fly Ash as Alternative Cement Replacement Jan Foˇrt 1,2,* , Jiˇrí Šál 2, Jaroslav Žák 2 and Robert Cernˇ ý 1 1 Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákutova 7, 166 29 Prague, Czech Republic; [email protected] 2 Institute of Technology and Business in Ceskˇ é Budˇejovice,Okružní 10, 370 01 Ceskˇ é Budˇejovice, Czech Republic; [email protected] (J.Š.); [email protected] (J.Ž.) * Correspondence: [email protected] Received: 16 October 2020; Accepted: 15 November 2020; Published: 17 November 2020 Abstract: The abandonment of coal energy plants in the near future will result in a substantially reduced availability of the coal fly ash broadly used as an efficient supplementary material. In line with the growth of alternative and renewable energy resources, the amount of biomass-based ash rises substantially. Nevertheless, a diverse chemical composition prevents a broader utilization of biomass-based fly ash compared to coal ash on an industrial scale. On this account, the present work is aimed at investigating the basic physical and mechanical properties of concrete mortars modified by a high volume of biomass fly ash (BFA) from wood combustion. Delivered results confirm a significant potential of BFA in the building industry. Experimental analysis of concrete mortars with BFA reveals preservation or even improvement of compressive and bending strength up to 30 wt.% cement replacement. On the contrary, higher dosages induce a gradual decrease in mechanical performance. The performed Life Cycle Assessment analysis reveals the perspective of BFA incorporation taking into account environmental issues considering the ratio between preservation of mechanical performance per normalized endpoint environmental score that allows a direct comparison with other alternatives. -
Alkali-Silica Reactivity: an Overview of Research
SHRP-C-342 Alkali-Silica Reactivity: An Overview of Research Richard Helmuth Construction Technology Laboratories, Inc. With contributions by: David Stark Construction Technology Laboratories, Inc. Sidney Diamond Purdue University Micheline Moranville-Regourd Ecole Normale Superieure de Cachan Strategic Highway Research Program National Research Council Washington, DC 1993 Publication No. SHRP-C-342 ISBN 0-30cL05602-0 Contract C-202 Product No. 2010 Program Manager: Don M. Harriott Project Maxtager: Inam Jawed Program AIea Secretary: Carina Hreib Copyeditor: Katharyn L. Bine Brosseau May 1993 key words: additives aggregate alkali-silica reaction cracking expansion portland cement concrete standards Strategic Highway Research Program 2101 Consti!ution Avenue N.W. Washington, DC 20418 (202) 334-3774 The publicat:Lon of this report does not necessarily indicate approval or endorsement by the National Academy of Sciences, the United States Government, or the American Association of State Highway and Transportation Officials or its member states of the findings, opinions, conclusions, or recommendations either inferred or specifically expressed herein. ©1993 National Academy of Sciences 1.5M/NAP/593 Acknowledgments The research described herein was supported by the Strategic Highway Research Program (SHRP). SHRP is a unit of the National Research Council that was authorized by section 128 of the Surface Transportation and Uniform Relocation Assistance Act of 1987. This document has been written as a product of Strategic Highway Research Program (SHRP) Contract SHRP-87-C-202, "Eliminating or Minimizing Alkali-Silica Reactivity." The prime contractor for this project is Construction Technology Laboratories, with Purdue University, and Ecole Normale Superieure de Cachan, as subcontractors. Fundamental studies were initiated in Task A. -
Guide to Safety Procedures for Vertical Concrete Formwork
F401 Guide to Safety Procedures for Vertical Concrete Formwork SCAFFOLDING, SHORING AND FORMING INSTITUTE, INC. 1300 SUMNER AVENUE, CLEVELAND, OHIO 44115 (216) 241-7333 F401 F O R E W O R D The “Guide to Safety Procedures for Vertical Concrete Formwork” has been prepared by the Forming Section Engineering Committee of the Scaffolding, Shoring & Forming Institute, Inc., 1300 Sumner Avenue, Cleveland, Ohio 44115. It is suggested that the reader also refer to other related publications available from the Scaffolding, Shoring & Forming Institute. The SSFI welcomes any comments or suggestions regarding this publication. Contact the Institute at the following address: Scaffolding, Shoring and Forming Institute, 1300 Sumner Ave., Cleveland, OH 44115. i F401 CONTENTS PAGE Introduction ........................................................................................ 1 Section 1 - General................................................................................ 2 Section 2 - Erection of Formwork......................................................... 2 Section 3 - Bracing................................................................................ 3 Section 4 - Walkways/Scaffold Brackets.............................................. 3 Section 5 - Special Applications........................................................... 4 Section 6 - Inspection............................................................................ 4 Section 7 - Concrete Placing................................................................. 5 Section -
We Now Know That the Maximum Level That Avoids
Using ash in concrete is nothing new. h e Romans rials derived from coal combustion products, includ- used volcanic ash in their spectacular construction ing fly ash, nationwide. projects long before the introduction of Portland cement, “Fly ash is composed of the non-combustible mineral having discovered its value as a hardening agent when portion of coal. When coal is consumed in a power plant, mixed with lime. h e ancient Romans used volcanic ash it’s i rst ground to the i neness of powder. Blown into as an admix to erect buildings such as the Pantheon and the power plant’s boiler, the carbon is consumed – leav- Coliseum, roads, and aqueducts. Remember, these struc- ing molten particles rich in silica, alumina, and calcium. tures are more than 2,000 years old. h ese particles solidify as microscopic, glassy spheres Fly ash concrete was first used in the U.S. in the that are collected from the power plant’s exhaust before 1920s for dam construction, when engineers found that it reduced the total cement requirement. Today, as more projects seek LEED certification, ash is resurfac- WE NOW KNOW THAT THE ing as a popular environmentally-friendly alternative MAXIMUM LEVEL THAT AVOIDS to Portland cement. No longer are we using volcanic COMPLICATIONS IN ADHERING FLOOR ash, of course, but coal fly ash is gaining ground as the COVERING IS 15% FLY ASH. green alternative of choice for LEED projects. Many of the projects and the millions of square yards of LEED flooring we’ve installed in recent years used ash in the they can “l y” away – hence the product’s name: l y ash,” cement mixture. -
Report No. REC-ERC-82-1. Fly Ash and Fly Ash Concrete
May 1984 Engineering and Research Center U. S. Department of the Interior Bureau of Reclamation Bureau ot Reclamation TECHNICAL REPORT STANDARD TITLE PAGE Fly Ash and Fly Ash Concrete May 1984 6. PERFORMING ORGANIZATION CODE 7. AUTHOR(S)-. 8. PERFORMING ORGANIZATION Edwin R. Dunstan, Jr. REPORT NO. I REC-ERC-82-1 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. WORK UNIT NO. Bureau of Reclamation, Engineering and Research Center 11. CONTRACT OR GRANT NO. Denver, Colorado 80225 10781 V0195 13. TYPE OF REPORT AND PERIOD COVERED 2. SPONSORING AGENCY NAME AND ADDRESS Same 14. SPONSORING AGENCY CODE DlBR 15. SUPPLEMENTARY NOTES Microfiche and/or hard copy available at the Engineering and Research Center. Denver. Colorado. Editor: RNW 16. ABSTRACT Fly ash is a residue that results from the combustion of ground or powdered coal. Historically, fly ash has been referred to as a ponolan and is used to reduce the amount of portland cement in concrete. However, in many Western States fly ashes have cementitious properties as well as pozzolanic properties, and they are capable of producing good strengths without portland cement. This study discusses test results of several ashes according to ASTM: C 6 18. Standard Specification for Fly Ash and Raw or Calcined Natural Pozzolan for Use as a Mineral Admixture in Portland Cement Concrete. Many changes are suggested. The replacement of 15 to 25 percent by mass of portland cement in concrete is examined. A few highly cementitious ashes were used to make concrete without portland cement. A new cement was developed that consists of over 90-percent fly ash and anhydrous CaS04.Test data for most concretes include: mix proportions, compressive strength, elasticity, drying shrinkage. -
21851 Concrete Reinforcment Catalog
R EBAR Reinforcing bar or rebar is a hot rolled steel product used primarily for reinforcing concrete structures. Meeting ASTM specifications, rebar grades are available varying in yield strength, bend test requirements, composition. Grade 300 / Grade 40 Sizes Due to lower carbon content, grade 300 is easier Metric Bar Nominal Weight Weight to bend. Size Number Size Per Ft. Per 20' (lbs.) (lbs.) Typical applications: Residential construction 10 #3 3/8" (.3759) .376 7.52 Grade 420 / Grade 60 13 #4 1/2" (.5009) .668 13.36 Used in high stress rated applications: higher carbon 16 #5 5/8" (.6259) 1.043 20.86 content provides increased vertical strength. 19 #6 3/4" (.7509) 1.502 30.04 22 #7 7/8" (.8759) 2.044 40.88 Typical applications: Dams, atomic power stations 25 #8 1" (1.0009) 2.670 53.40 or commercial buildings 29 #9 1-1/8" (1.1289) 3.400 68.00 No-Grade 32 #10 1-1/4" (1.2709) 4.303 86.06 No-grade rebar is not tested as it is rolled. Cannot 36 #11 1-3/8" (1.4109) 5.313 106.26 be used in applications where mill certified products 43 #14 1-3/4" (1.6939) 7.650 153.00 are required. 57 #18 2-1/4" (2.2579) 13.600 272.00 Typical applications: Sidewalks, driveways, or Cut To Size Rebar other flat pours Cut to size rebar has a variety of applications. It can be ASTM Specifications used for concrete reinforcement, construction stakes, ASTM A 615 landscaping projects or tree and vegetable stakes. -
How to Make Concrete More Sustainable Harald Justnes1
Journal of Advanced Concrete Technology Vol. 13, 147-154, March 2015 / Copyright © 2015 Japan Concrete Institute 147 Scientific paper How to Make Concrete More Sustainable Harald Justnes1 A selected paper of ICCS13, Tokyo 2013. Received 12 November 2013, accepted 16 February 2015 doi:10.3151/jact.13.147 Abstract Production of cement is ranking 3rd in causes of man-made carbon dioxide emissions world-wide. Thus, in order to make concrete more sustainable one may work along one or more of the following routes; 1) Replacing cement in con- crete with larger amounts of supplementary cementing materials (SCMs) than usual, 2) Replacing cement in concrete with combinations of SCMs leading to synergic reactions enhancing strength, 3) Producing leaner concrete with less cement per cubic meter utilizing plasticizers and 4) Making concrete with local aggregate susceptible to alkali silica reaction (ASR) by using cement replacements, thus avoiding long transport of non-reactive aggregate. 1 Introduction SCMs, also uncommon ones like calcined marl 2. Replacing cement in concrete with combinations of The cement industry world-wide is calculated to bring SCMs leading to synergic reactions enhancing about 5-8% of the total global anthropogenic carbon strength dioxide (CO2) emissions. The general estimate is about 3. Producing leaner concrete with less cement per cubic 1 tonne of CO2 emission per tonne clinker produced, if meter utilizing plasticizers. fossil fuel is used and no measures are taken to reduce it. 4. Making concrete with local aggregate susceptible to The 3rd rank is not because cement is such a bad mate- alkali silica reaction (ASR) by using cement re- rial with respect to CO2 emissions, but owing to the fact placements, thus avoiding long transport of non- that it is so widely used to construct the infrastructure reactive aggregate and buildings of modern society as we know it. -
AASHTO GFRP-Reinforced Concrete Design Training Course
AASHTO GFRP-Reinforced Concrete Design Training Course GoToWebinar by: Professor Antonio Nanni Introducing the Schedule 9:35 am Introduction & Materials (Prof. Antonio Nanni) → Review Questions (Dr. Francisco De Caso) 10:30 am Flexure Response (Prof. Antonio Nanni) → Review Questions (Dr. Francisco De Caso) *** Coffee Break *** → Design Example: Flat Slab (Roberto Rodriguez) 12:00 pm Shear Response (Prof. Antonio Nanni) → Review Questions (Dr. Francisco De Caso) *** Lunch Break (1 hour) *** 1:30 pm → Design Example: Bent Cap (Nafiseh Kiani) 2:00 pm Axial Response (Prof. Antonio Nanni) → Review Questions (Dr. Francisco De Caso) → Design Example: Soldier Pile (Roberto Rodriguez) *** Coffee Break *** 3:00 pm Case Studies & Field Operations (Prof. Nanni & Steve Nolan) 1 Introducing our Presenters & Support Prof. Antonio Nanni Dr. Francisco DeCaso P.E. PhD. P.E. PhD. Roberto Rodriguez, Nafiseh Kiani P.E. (PhD. Candidate) (PhD. Candidate) Alvaro Ruiz, Christian Steputat, (PhD. Candidate) P.E. (PhD. Candidate) Steve Nolan, P2.E. Support Material - Handouts 3 Support Material - Handouts 4 Support Material - Handouts 5 Support Material - Handouts 6 Support Material - Workbook 7 Support Material - Workbook 8 Other Support Material - FDOT https://www.fdot.gov/structures/innovation/FRP.shtm 9 Another Training Opportunity CFRP-Prestressed Concrete Designer Training for Bridges & Structures – Professor Abdeldjelil “DJ” Belarbi, on September 9th, 2020 This 6-hour online training is focused on providing practical designer guidance to FDOT engineers and consultants for structures utilizing Carbon Fiber-Reinforced Polymer (CFRP) Strands for pretensioned bridge beams, bearing piles, and sheet piles. Basic design principles and design examples will be presented for typical FDOT bridge precast elements. Register Now at: https://attendee.gotowebinar.com/register/5898046861643311883 There is no cost to attend this webinar training. -
Alkali Silica Reaction Mitigation Using High Volume Class C Fly Ash William Joseph Phillips University of Arkansas, Fayetteville
University of Arkansas, Fayetteville ScholarWorks@UARK Theses and Dissertations 7-2015 Alkali Silica Reaction Mitigation Using High Volume Class C Fly Ash William Joseph Phillips University of Arkansas, Fayetteville Follow this and additional works at: http://scholarworks.uark.edu/etd Part of the Civil Engineering Commons, and the Transportation Engineering Commons Recommended Citation Phillips, William Joseph, "Alkali Silica Reaction Mitigation Using High Volume Class C Fly Ash" (2015). Theses and Dissertations. 1306. http://scholarworks.uark.edu/etd/1306 This Thesis is brought to you for free and open access by ScholarWorks@UARK. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of ScholarWorks@UARK. For more information, please contact [email protected], [email protected]. Alkali Silica Reaction Mitigation Using High Volume Class C Fly Ash A thesis submitted in partial fulfillment Of the requirements for the degree of Masters of Science in Civil Engineering By William J. Phillips Missouri University of Science & Technology Bachelors of Science in Civil Engineering, 2013 July 2015 University of Arkansas This thesis is approved for recommendation to the Graduate Council _____________________________ Dr. W. Micah Hale Thesis Director _____________________________ _____________________________ Dr. Ernest Heymsfield Dr. Clinton M. Wood Committee Member Committee Member ABSTRACT Alkali-Silica Reaction (ASR) is a neutralization reaction that occurs between an acid (silicic acid) and a basic pH pore solution (Calcium Oxide, Potassium Oxide, and Sodium Oxide). ASR causes deleterious expansion within concrete, which can cause durability issues decreasing the life span of concrete. ASR in concrete has been found in increasing quantities since its discovery in 1940 by Stanton. -
Class C Fly Ash As a Full Or Partial Replacement for Portland Cement Or Lime
68 TRANSPORTATION R ESEARCH RECORD 1219 Class C Fly Ash as a Full or Partial Replacement for Portland Cement or Lime KENNETH L. McMANrs AND ARA ARMAN A study was undertaken to evaluate the stabilization or mod Designation C 207, Type N) and a Type I portland cement ification of sands and clays using ASTM Class C fly ash as a (AASHTO Designation M85) were used in the study. full or partial replacement for hydraulic cement or hydrated A base or subbase material is usually evaluated with respect lime. Strength and durability tests demonstrated that the Class to its strength and durability. Louisiana Department of Trans C fly ashes of the study could be substituted for cement in portation and Development (DOTD) criteria (TR 432-82) some sands. Improvement of the sands was provided by the were used to evaluate the performance of the sand specimens matrix formed with fly ash acting as a filler and as a cementing (i.e., sand plus fly ash alone, sand plus fly ash and lime, sand agent. The test results indicate the importance of the gradation plus fly ash and cement, and sand plus cement alone). This characteristics of the materials and the effects on matrix quality due to the presence of fines in the natural sands. Also, improve specification required the minimum cement content to cor ments in the plastic properties and gains in soil support with respond to a strength of 250 psi with a 7-day curing period at the addition of fly ash and/or lime were evaluated for two clays. -
Interlocking Concrete Masonry Unit Geometry Design Raquel Avila Santa Clara Univeristy
Santa Clara University Scholar Commons Civil Engineering Senior Theses Engineering Senior Theses 6-13-2015 Interlocking concrete masonry unit geometry design Raquel Avila Santa Clara Univeristy Nick Jensen Santa Clara Univeristy Follow this and additional works at: https://scholarcommons.scu.edu/ceng_senior Part of the Civil and Environmental Engineering Commons Recommended Citation Avila, Raquel and Jensen, Nick, "Interlocking concrete masonry unit geometry design" (2015). Civil Engineering Senior Theses. 31. https://scholarcommons.scu.edu/ceng_senior/31 This Thesis is brought to you for free and open access by the Engineering Senior Theses at Scholar Commons. It has been accepted for inclusion in Civil Engineering Senior Theses by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. INTERLOCKING CONCRETE MASONRY UNIT GEOMETRY DESIGN By Raquel Avila, Nick Jensen SENIOR DESIGN PROJECT REPORT Submitted to the Department of Civil Engineering of SANTA CLARA UNIVERSITY in Partial Fulfillment of the Requirements for the degree of Bachelor of Science in Civil Engineering Santa Clara, California Spring 2015 Abstract Earthquakes in Haiti and Nepal left many people devastated. Millions of people were initially displaced and forced to reside in displacement camps. Developing countries like these need a form of economical construction. Our design and manufacturing process for interlocking CMU (concrete masonry unit) blocks can help build low-cost homes quickly and efficiently. Wall construction costs are reduced because skilled masons are not needed to build the wall. Instead, unskilled homeowners and laborers can stack the interlocking blocks, which serve as forms for the subsequent placement of reinforcement and grout within some of the CMU block voids. -
Stainless Steel Prestressing Strands and Bars for Use in Prestressed Concrete Girders and Slabs
Stainless Steel Prestressing Strands and Bars for Use in Prestressed Concrete Girders and Slabs Morgan State University The Pennsylvania State University University of Maryland University of Virginia Virginia Polytechnic Institute & State University West Virginia University The Pennsylvania State University The Thomas D. Larson Pennsylvania Transportation Institute Transportation Research Building University Park, PA 16802-4710 Phone: 814-865-1891 Fax: 814-863-3707 www.mautc.psu.edu MD-13-SP--SPMSU-3-11 Martin O’Malley, Governor James T. Smith, Secretary Anthony G. Brown, Lt. Governor Melinda B. Peters, Administrator STATE HIGHWAY ADMINISTRATION Research Report STAINLESS STEEL PRESTRESSING STRANDS AND BARS FOR USE IN PRESTRESSED CONCRETE GIRDERS AND SLABS MORGAN STATE UNIVERSITY DEPARTMENT OF CIVIL ENGINEERING PROJECT NUMBER SP309B4G FINAL REPORT FEBRUARY 2015 1. Report No. 2. Government Accession No. 3. Recipient’s Catalog No. MSU- 2013-02 4. Title and Subtitle 5. Report Date Stainless Steel Prestressing Strands and Bars for Use in February 2015 Prestressed Concrete Girders and Slabs 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. Principal Investigator: Dr. Monique Head Researchers: Ebony Ashby-Bey, Kyle Edmonds, Steve Efe, Siafa Grose and Isaac Mason 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Morgan State University Clarence M. Mitchell, Jr., School of Engineering Department of Civil Engineering 11. Contract or Grant No. 1700 E. Cold Spring Lane Baltimore, Maryland 21251 DTRT12-G-UTC03 12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered US Department of Transportation Final Research & Innovative Technology Admin UTC Program, RDT-30 14. Sponsoring Agency Code 1200 New Jersey Ave., SE Washington, DC 20590 15.