Components of Concrete Desirable Properties of Concrete
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Experimental Investigation on Nano Concrete with Nano Silica and M-Sand
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 06 Issue: 03 | Mar 2019 www.irjet.net p-ISSN: 2395-0072 EXPERIMENTAL INVESTIGATION ON NANO CONCRETE WITH NANO SILICA AND M-SAND Mohan Raj.B1, Sugila Devi.G2 1PG Student, Nadar Saraswathi College of Engineering and Technology, Theni, Tamilnadu, India. 2Assistant Professor, Nadar Saraswathi College of Engineering and Technology, Theni, Tamilnadu, India. ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract - The influence of Nano-Silica on various material is Nano Silica (NS). The advancement made by the properties of concrete is obtained by replacing the cement study of concrete at Nano scale has proved the Nano silica is with various percentages of Nano-Silica. Nano-Silica is used as much better than silica fume used in conventional concrete. a partial replacement for cement in the range of 3%, 3.5%, Now, the researchers are capitalizing on nanotechnology to and 10% for M20 mix. Specimens are casted using Nano-Silica innovate a new generation of concrete materials that concrete. Laboratory tests conducted to determine the overcome the above drawbacks and trying to achieve the compressive strength, split tensile and flexural strength of sustainable concrete structures. Evolution of materials is Nano-Silica concrete at the age of 7, 14 and 28 days. Results need of the day for improved or better performance for indicate that the concrete, by using Nano-Silica powder, was special engineering applications and modifying the bulk able to increase its compressive strength. However, the density state of materials in terms of composition or microstructure is reduce compared to standard mix of concrete. -
Influence of Constituents' Properties on the Fracture Properties of High Strength Concrete
Influence of Constituents' Properties on the Fracture Properties of High Strength Concrete by Jeffrey Ramzi Karam B.S.C.E., Washington University in St. Louis (1995) SUBMITTED TO THE DEPARTMENT OF CIVIL AND ENVIRONMENTAL ENGINEERING IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE MASTER OF SCIENCE IN CIVIL AND ENVIRONMENTAL ENGINEERING at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY January, 1997 © 1997 Massachusetts Institute of Technology. All rights reserved. Signature of Author Depart/cht ofCivil and Environmental Engineering ;ember, 1996 Certified by 3iuyiik6ztrk -pervisor Certified by Joseph M. Sussman Chairman, Departmental Committee on Graduate Students C) 2 I Influence of Constituents' Properties on the Fracture Properties of High Strength Concrete by Jeffrey Ramzi Karam Submitted to the Department of Civil and Environmental Engineering January, 1997 in partial fulfillment of the requirements for the degree of Master of Science in Civil and Environmental Engineering Abstract The mechanical properties of concrete are known to be highly dependent on the characteristics of the interfacial region. Through the use of admixtures the properties of the interfacial region have been altered such that concretes of exceptional strength are now achievable. As with most engineering materials, the improved strength comes at the expense of ductility. The objective of this research was to ascertain how the properties of the basic constituents of concrete affect the ductility. An interface fracture energy methodology was used to study the influence of various internal parameters. The parameters investigated for normal and high strength mortars were: aggregate size, aggregate volume fraction, and aggregate type. Additionally, a novel code-like equation was developed in order to predict the fracture energy of a cementitious composite based on the material properties of the constituents. -
Vermiculite Concrete Introduction Vermiculite Concrete Is a Low Density Non-Structural Construction Product
Vermiculite Concrete Introduction Vermiculite concrete is a low density non-structural construction product. It is insulating (both thermally and acoustically) and intrinsically fire resistant. It is normally made simply by mixing exfoliated vermiculite as the aggregate, with cement and water, plus additives such as plasticisers if required. The ratio of exfoliated vermiculite aggregate to cement and the vermiculite grade can be varied to the properties such as strength and insulation as required for the concrete. The applications for vermiculite concrete are however, all non-structural. Vermiculite concretes can also be produced containing other lightweight aggregates, such as expanded perlite, to give differing physical properties. Normally the type of cement used in these mixes is Ordinary Portland Cement (O.P.C), although a higher initial strength may be obtained using Rapid Hardening Portland Cement (R.H.P.C). For high temperature refractory applications, high alumina (luminate in the USA) cements may be used with great success to manufacture lightweight in-situ cast insulation mixes and back up insulation products. However, these applications are beyond the scope of this specific application note. Applications for Vermiculite Concrete The principal applications for vermiculite concrete are for in-situ site mixed applications such as: • Floor and roof screeds • Void filling insulation mixes around chimneys, back boilers and fire backs • Blocks and slabs • Swimming pool bases [see separate application note for this application] Vermiculite concrete can be easily cut, sawed, nailed or screwed. The lower density vermiculite concrete screeds are usually covered with a denser topping mix of 4:1 or 5:1 sand to cement mix to a minimum depth of 25mm (1 inch); the screed and denser more load distributing topping should ideally be laid monolithically to prevent dis-bonding and shear fracturing between the screed and the topping. -
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. -
The Effects of Alkali-Silica Reaction on the Mechanical Properties of Concretes with Three Different Types of Reactive Aggregate
Technical Paper Okpin Na* DOI: 10.1002/suco.201400062 Yunping Xi Edward Ou Victor E. Saouma The effects of alkali-silica reaction on the mechanical properties of concretes with three different types of reactive aggregate This paper investigates the degradation of the mechanical prop- environment, the product of ASR is expansive, which is erties of concretes made with three types of aggregate affected detrimental to concrete structures [1, 2]. by alkali-silica reaction (ASR). Three standard testing methods ASR is a chemical reaction between the reactive – ASTM C289, JASS 5N T-603 and ASTM C1260 – were used to silica in the aggregate and the alkalis (Na2O and K2O) in identify the reactivity of ASR of the three aggregates selected. Portland cement. This chemical reaction produces alkali- The test results show that all three aggregates are potentially silica gel swelling with the absorption of the moisture deleterious. A new acceleration method based on JASS 5N T-603 from the surrounding cement paste. The expansive gel and ASTM C1260 was proposed for concrete specimens. In the can cause cracking in the concrete. Therefore, the neces- acceleration method, cylindrical concrete specimens were used, sary conditions for the expansive ASR gel to form in the additional alkali material was added to the concrete mixture and concrete are a sufficiently high alkali concentration in the the specimens were stored under conditions similar to ASTM cement, high moisture content in the concrete and reac- C1260. The preconditioned concrete specimens were then used tive aggregates. for evaluating the mechanical properties of the ASR-affected In order to control or prevent the occurrence of concrete in terms of strength and stiffness. -
On the Structure of the Roman Pantheon 25
College Art Association http://www.jstor.org/stable/3050861 . Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp. JSTOR's Terms and Conditions of Use provides, in part, that unless you have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in the JSTOR archive only for your personal, non-commercial use. Please contact the publisher regarding any further use of this work. Publisher contact information may be obtained at . http://www.jstor.org/action/showPublisher?publisherCode=caa. Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printed page of such transmission. JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. College Art Association is collaborating with JSTOR to digitize, preserve and extend access to The Art Bulletin. http://www.jstor.org On the Structureof the Roman Pantheon Robert Mark and Paul Hutchinson Since the time of its construction, the bold, brilliantly simple schema of Hadrian's Pantheon has inspired much emulation, commendation, and even fear. Modern commentators tend to view the building as a high point in an "architectural rev- olution" brought about mainly through the Roman development of a superior poz- zolana concrete that lent itself to the forming of unitary, three-dimensional struc- tures. -
Portland Cement Concrete
B Highway Materials Engineering Course PARTICIPANT WORKBOOK Portland Cement Concrete MODULE G Ti Table of Contents About This Workbook .................................................................................................................. 2 Course Overview .......................................................................................................................... 3 Introduction ................................................................................................................................. 3 Module G Overview ..................................................................................................................... 4 Module Goals ............................................................................................................................... 5 Learning Outcomes ...................................................................................................................... 5 ILT Instruction Icons ..................................................................................................................... 9 Module G Lesson 8 Review ..................................................................................................... G8-1 Module G Lesson 9 Basic Mix Design and Proportioning ....................................................... G9-1 Module G Lesson 10 Reinforcing and Corrosion ..................................................................G10-1 Module G Lesson 11 Hot Topics ...........................................................................................G11-1 -
Guide to Concrete Repair Second Edition
ON r in the West August 2015 Guide to Concrete Repair Second Edition Prepared by: Kurt F. von Fay, Civil Engineer Concrete, Geotechnical, and Structural Laboratory U.S. Department of the Interior Bureau of Reclamation Technical Service Center August 2015 Mission Statements The U.S. Department of the Interior protects America’s natural resources and heritage, honors our cultures and tribal communities, and supplies the energy to power our future. The mission of the Bureau of Reclamation is to manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public. Acknowledgments Acknowledgment is due the original author of this guide, W. Glenn Smoak, for all his efforts to prepare the first edition. For this edition, many people were involved in conducting research and field work, which provided valuable information for this update, and their contributions and hard work are greatly appreciated. They include Kurt D. Mitchell, Richard Pepin, Gregg Day, Jim Bowen, Dr. Alexander Vaysburd, Dr. Benoit Bissonnette, Maxim Morency, Brandon Poos, Westin Joy, David (Warren) Starbuck, Dr. Matthew Klein, and John (Bret) Robertson. Dr. William F. Kepler obtained much of the funding to prepare this updated guide. Nancy Arthur worked extensively on reviewing and editing the guide specifications sections and was a great help making sure they said what I meant to say. Teri Manross deserves recognition for the numerous hours she put into reviewing, editing and formatting this Guide. The assistance of these and numerous others is gratefully acknowledged. Contents PART I: RECLAMATION'S METHODOLOGY FOR CONCRETE MAINTENANCE AND REPAIR Page 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 -
Effect of Formwork Removal Time Reduction on Construction
applied sciences Article Effect of Formwork Removal Time Reduction on Construction Productivity Improvement by Mix Design of Early Strength Concrete 1, 2, 3 3, 3 Taegyu Lee y , Jaehyun Lee y, Jinsung Kim , Hyeonggil Choi * and Dong-Eun Lee 1 Department of Fire and Disaster Prevention, Semyung University, 65 Semyung-ro, Jecheon-si, Chungbuk 27136, Korea; [email protected] 2 Department of Safety Engineering, Seoul National University of Science and Technology, 232 Gongneung-ro, Nowon-gu, Seoul 01811, Korea; [email protected] 3 School of Architecture, Civil, Environment, and Energy Engineering, Kyungpook National University, 80 Daehakro, Bukgu, Daegu 41566, Korea; [email protected] (J.K.); [email protected] (D.-E.L.) * Correspondence: [email protected]; Tel.: +82-53-950-5596 These authors contributed equally to this work. y Received: 4 September 2020; Accepted: 6 October 2020; Published: 11 October 2020 Abstract: In this study, we examined the effects of cement fineness, SO3 content, an accelerating agent, and chemical admixtures mixed with unit weights of cement on concrete early strength using concrete mixtures. C24 (characteristic value of concrete, 24 MPa) was used in the experiment conducted. Ordinary Portland cement (OPC), high fineness and SO3 OPC (HFS_OPC), and Early Portland cement (EPC) were selected as the study materials. The unit weights of cement were set to OPC 330, 350, and 380. Further, a concrete mixture was prepared with a triethanolamine (TEA)-based chemical admixture to HFS. A raw material analysis was conducted, and the compressive strength, temperature history, and maturity (D h) were examined. Then, the vertical formwork removal time was evaluated · according to the criterion of each country. -
Portland Cement User's Guide == Steps == # Plan Your Concrete
Portland Cement User’s guide == Steps == # Plan your concrete project carefully. There is a set sequence of steps you must take to be successful, and following them will save you a lot of problems later on. # Purchase or gather the raw materials for your concrete. You will need Portland type I or II cement, masonry or builder's sand or other clean sand, and if you want, as a filler, gravel or crushed limestone. The Portland cement usually comes in one cubic foot bags, weighing in at about 96 pounds each, so you may need help handling them, as well as a truck to haul it. # Build a mixing box, or get a good, sturdy wheel barrow to mix the materials in. If it is a large project, rent a concrete mixer to do the hardest part of the work for you. We have mixed as much as 6 or 8 cubic feet with a mason's hoe and shovel, in a large plastic tub, so not having the best equipment shouldn't stop you from trying it. # Allow yourself time to complete the whole process when you begin. If the concrete is a large "finished" slab, start early in the morning and gather all the help you can. # Build the form you are placing the concrete in, brace it off securely, level and plumb it up, and then carefully measure the dimensions to determine the volume in cubic feet. This is done by multiplying width X length X height in feet. An example would be 5 ft. X 2 ft. -
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.