DOCSLIB.ORG

Properties of Concrete

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Properties of Concrete Lesson Plans for Module 27303-14 PROPERTIES OF CONCRETE Module 27303-14 describes the properties, characteristics, and uses of cement, aggregates, and other materials that, when mixed together, form different types of concrete. The text covers procedures for estimating concrete volume and for testing freshly mixed concrete as well as methods and materials for curing concrete. Objectives Learning Objective 3 Learning Objective 1 • Describe the methods for testing concrete. • Identify various concrete ingredients and de- a. Describe the proper procedure for sampling scribe their purpose in a concrete mixture. concrete. a. Explain how portland cement affects a b. Explain the purpose of a slump test. concrete mixture and list the types of portland c. Describe how a concrete compression test is cement. performed. b. Describe the characteristics of aggregate used Learning Objective 4 in a concrete mixture. • Calculate concrete volume for rectangular or c. List the characteristics of water used in a circular structures. concrete mixture. a. Calculate rectangular volume. d. List types of concrete admixtures and b. Calculate circular volume. describe how they affect a concrete mixture. Learning Objective 2 Performance Tasks • Identify proper concrete mixture measure- Performance Task 1 (Learning Objective 3) ments and curing methods. • Perform a concrete slump test or create a con- a. Describe normal concrete-mix proportions crete test cylinder. and measurements. Performance Task 2 (Learning Objective 4) b. List special types of concrete. • Calculate concrete volume requirements using c. Describe the properties of air-entrained formulas, concrete tables, and/or concrete cal- concrete. culators, as applicable. d. Describe how concrete is cured. Teaching Time: 10 hours (Four 2.5-hour Classroom Sessions) Session time may be adjusted to accommodate your class size, schedule, and teaching style. Prerequisites Core Curriculum, Carpentry Level One, and Carpentry Level Two Before You Begin As you prepare for each session, allow sufficient time to review the course objectives, content, visual aids (in- cluding the PowerPoint® presentation), and these lesson plans, and to gather the required equipment and materi- als. Consider time required for demonstrations, laboratories, field trips, and testing. Using your access code, download the Module Examinations and Performance Profile Sheets from www.nccerirc.com. The passing score for submission into NCCER’s Registry is 70 percent or above for the Mod- ule Examination; performance testing is graded pass or fail. 27303-14 Properties of Concrete Module One i LP_M01_27303-14_Rev.indd 1 2/5/15 12:04 PM Safety Considerations This module requires that trainees work around cement. Safety is paramount in the carpentry trade and safe habits and practices must be emphasized whenever possible. Performance Tasks must be completed under your supervision. Each trainee must use required PPE and follow safe tool practices and procedures. Classroom Equipment Equipment and Materials for Laboratories and Materials and Performance Testing Whiteboard/chalkboard Personal protective equipment Samples of acceptable and Markers/chalk Eye protection unacceptable aggregates Pencils and paper Gloves Samples of admixtures Carpentry Level Three PowerPoint® Hard hat Samples of coloring agents Presentation Slides Construction calculator Samples of fine and/or coarse Computer Containers of water aggregate Copies of the Module Examination Copies of a completed concrete test Samples of portland cement and Performance Profile Sheets recording form Set of commercial construction Vendor-supplied videos/DVDs Copies of or excerpts from ASTM drawings showing concrete mixing operations C150, Standard Specification for Set of residential construction (optional) Portland Cement drawings TV/DVD player Copy of performance specifications Shovel Cylindrical molds Sieve or filter Digital thermometers Slide-rule concrete calculator Hand grips Slump cone mold Materials used for concrete hydration, Straightedge including waterproof curing paper, Tamping rod plastic sheeting, burlap mats, Tape measure blankets, and curing compounds Water Metal tags and tag wires Wheelbarrow Nonabsorbent surface Additional Resources and References This module presents thorough resources for task training. The following resource material is suggested for further study: American Concrete Institute. www.concrete.org ASTM C31, Standard Practice for Making and Curing Concrete Test Specimens in the Field, Latest Edition. West Conshohocken, PA: ASTM International. ASTM C33, Standard Specifications for Concrete Aggregate, Latest Edition, West Conshohocken, PA: ASTM International. ASTM C39, Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens, Latest Edi- tion. West Conshohocken, PA: ASTM International. ASTM C78, Standard Test Method for Flexural Strength of Concrete (Using Simple Beam with Third-Point Loading), Latest Edition. West Conshohocken, PA: ASTM International. ASTM C138, Standard Test Method for Density (Unit Weight), Yield, and Air Content (Gravimetric) of Concrete, Latest Edition. West Conshohocken, PA: ASTM International. ASTM C143, Standard Test Method for Slump of Hydraulic-Cement Concrete, Latest Edition. West Con- shohocken, PA: ASTM International. ASTM C150, Standard Specification for Portland Cement, Latest Edition, West Conshohocken, PA: ASTM International. ASTM C157, Standard Test Method for Length Change of Hardened Hydraulic-Cement Mortar and Concrete, Latest Edition. West Conshohocken, PA: ASTM International. ii NCCER – Carpentry Level Three 27303-14 LP_M01_27303-14_Rev.indd 2 2/5/15 12:04 PM ASTM C171, Standard Specification for Sheet Materials for Curing Concrete, Latest Edition. West Con- shohocken, PA: ASTM International. ASTM C172, Standard Practice for Sampling Freshly Mixed Concrete, Latest Edition. West Conshohocken, PA: ASTM International. ASTM C173, Standard Test Method for Air Content of Freshly Mixed Concrete by the Volumetric Method, Lat- est Edition. West Conshohocken, PA: ASTM International. ASTM C231, Standard Test Method for Air Content of Freshly Mixed Concrete by the Pressure Method, Latest Edition. West Conshohocken, PA: ASTM International. ASTM C308, Standard Test Methods for Working, Initial Setting, and Service Strength Setting Times of Chem- ical-Resistant Resin Mortars, Latest Edition. West Conshohocken, PA: ASTM International. ASTM C403, Standard Test Method for Time of Setting of Concrete Mixtures by Penetration Resistance, Latest Edition. West Conshohocken, PA: ASTM International. ASTM C470, Standard Specification for Molds for Forming Concrete Test Cylinders Vertically, Latest Edition. West Conshohocken, PA: ASTM International. ASTM C494, Standard Specification for Chemical Admixtures for Concrete, Latest Edition. West Con- shohocken, PA: ASTM International. ASTM C595, Standard Specification for Blended Hydraulic Cements, Latest Edition, West Conshohocken, PA: ASTM International. ASTM C618, Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Con- crete, Latest Edition. West Conshohocken, PA: ASTM International. ASTM C666, Standard Test Method for Resistance of Concrete to Rapid Freezing and Thawing, Latest Edi- tion. West Conshohocken, PA: ASTM International. ASTM C1157, Standard Performance Specification for Hydraulic Cement, Latest Edition, West Conshohocken, PA: ASTM International. ASTM C1240, Standard Specification for Silica Fume Used in Cementitious Mixtures, Latest Edition, West Conshohocken, PA: ASTM International. ASTM C1315, Standard Specification for Liquid Membrane-Forming Compounds Having Special Properties for Curing and Sealing Concrete, Latest Edition, West Conshohocken, PA: ASTM International. ASTM D98, Standard Specification for Calcium Chloride, Latest Edition, West Conshohocken, PA: ASTM Inter- national. Cement Association of Canada. www.cement.ca Effect of Cement Characteristics on Concrete Properties. 2006. Portland Cement Association. Skokie, IL. Portland Cement Association. www.cement.org Properties of Concrete. 2011. A. M. Neville. Trans-Atlantic Publications, Inc. There are a number of online resources available for trainees who would like more information on the properties of concrete. A search for additional information may be assigned as homework to interested trainees. 27303-14 Properties of Concrete Module One iii LP_M01_27303-14_Rev.indd 3 2/5/15 12:04 PM LP_M01_27303-14_Rev.indd 4 2/5/15 12:04 PM Session Outline for Module 27303-14 PROPERTIES OF CONCRETE The lesson plan for this module is divided into four 2.5-hour sessions. Each session includes 10 minutes for administrative tasks and one 10-minute break. SEssION ONE SEssION THREE Session One introduces concrete ingredients Session Three introduces concrete volume and their impact on a concrete mixture. calculations. 1. Show Session One PowerPoint® presentation 1. Show Session Three PowerPoint® slides. presentation slides. 2. Introduce trainees to hydration and its 2. Introduce trainees to the proper technique for various stages. determining the volume of rectangular and circular solids. 3. Introduce trainees to the various types of aggregates and admixtures that may be used 3. Introduce trainees to the proper technique for in a concrete mixture. determining concrete volume. SEssION TWO SEssION FOUR Session Two introduces concrete mixture Session Four is a review and testing session. proportions, measurements, and concrete Have trainees complete the module Review testing.
Load more

Recommended publications
  • Impacts of Internal Curing on the Performance of Concrete Materials
    Impacts of Internal Curing on the Performance of Concrete Materials in the November 2017 Laboratory and the Field RESEARCH PROJECT TITLE Impacts of Internally Cured Concrete tech transfer summary Paving on Contraction Joint Spacing This research aimed to assess whether joint spacings could be SPONSORS increased in slabs containing lightweight fine aggregate (LWFA) as a Iowa Highway Research Board source of internal curing. (IHRB Project TR-676) Iowa Department of Transportation (InTrans Project 14-499) Objective PRINCIPAL INVESTIGATOR The objective of this project was to investigate the effects of internal Peter Taylor, Director National Concrete Pavement Technology curing on the performance of practical concrete mixtures designed for Center, Iowa State University the construction of jointed plain concrete pavements (JPCPs) in Iowa. 515-294-9333 / [email protected] (orcid.org/0000-0002-4030-1727) Background CO-PRINCIPAL INVESTIGATOR Concrete curing involves techniques and methods to maintain the Halil Ceylan, Director moisture and temperature of fresh concrete within desired ranges at Program for Sustainable Pavement early ages, which allows concrete to develop strength and durability. Engineering and Research (ProSPER), Institute for Transportation, Iowa State Various curing regimes, including external wet curing, insulation University membrane curing, and internal curing, can be used for different (orcid.org/0000-0003-1133-0366) applications and design characteristics. MORE INFORMATION Internal curing is designed to provide water reservoirs inside the www.cptechcenter.org concrete that aid curing without affecting the water-to-cementituous materials (w/cm) ratio of the mixture. Lightweight aggregates (LWAs) are commonly employed in the US to achieve internal curing. Internally cured (IC) concrete has several advantages over conventionally cured concrete: National CP Tech Center Iowa State University • Improved hydration in terms of uniform moisture distribution 2711 S.
    [Show full text]
  • 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.
    [Show full text]
  • 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.
    [Show full text]
  • Components of Concrete Desirable Properties of Concrete
    Components of Concrete Concrete is made up of two components, aggregates and paste. Aggregates are generally classified into two groups, fine and coarse, and occupy about 60 to 80 percent of the volume of concrete. The paste is composed of cement, water, and entrained air and ordinarily constitutes 20 to 40 percent of the total volume. In properly made concrete, the aggregate should consist of particles having adequate strength and weather resistance and should not contain materials having injurious effects. A well graded aggregate with low void content is desired for efficient use of paste. Each aggregate particle is completely coated with paste, and the space between the aggregate particles is completely filled with paste. The quality of the concrete is greatly dependent upon the quality of paste, which in turn, is dependent upon the ratio of water to cement content used, and the extent of curing. The cement and water combine chemically in a reaction, called hydration, which takes place very rapidly at first and then more and more slowly for a long period of time in favorable moisture conditions. More water is used in mixing concrete than is required for complete hydration of the cement. This is required to make the concrete plastic and more workable; however, as the paste is thinned with water, its quality is lowered, it has less strength, and it is less resistant to weather. For quality concrete, a proper proportion of water to cement is essential. Desirable Properties of Concrete Durability: Ability of hardened concrete to resist
    [Show full text]
  • Lumps and Balls in High-Slump Concrete: Reasons and Remedy Ivan R
    Florida International University FIU Digital Commons FIU Electronic Theses and Dissertations University Graduate School 6-24-2002 Lumps and balls in high-slump concrete: reasons and remedy Ivan R. Canino-Vazquez Florida International University Follow this and additional works at: http://digitalcommons.fiu.edu/etd Part of the Civil Engineering Commons Recommended Citation Canino-Vazquez, Ivan R., "Lumps and balls in high-slump concrete: reasons and remedy" (2002). FIU Electronic Theses and Dissertations. 1994. http://digitalcommons.fiu.edu/etd/1994 This work is brought to you for free and open access by the University Graduate School at FIU Digital Commons. It has been accepted for inclusion in FIU Electronic Theses and Dissertations by an authorized administrator of FIU Digital Commons. For more information, please contact [email protected]. FLORIDA INTERNATIONAL UNIVERSITY Miami, Florida LUMPS AND BALLS IN HIGH-SLUMP CONCRETE: REASONS AND REMEDY A thesis submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE in CIVIL ENGINEERING by Ivan R. Canino-Vazquez 2002 To: Dean Vish Prasad College of Engineering This thesis, written by Ivan R. Canino-Vazquez, and entitled Lumps and Balls In High- Slump Concrete: Reasons and Remedy, having been approved in respect to style and intellectual content, is referred to you for judgment. We have read this thesis and recommend that it be approved. Luis Prieto-Portar Nestor Gomez Irtishad Ahmad, Major Professor Date of Defense: June 24, 2002 The thesis of Ivan R. Canino-Vazquez is approved. Dean Vish Prasad College of Engineering Dean Douglas Wartzok University Graduate School Florida International University, 2002 ii DEDICATION A man once told me; "The most difficult part of receiving an academic degree, is getting to school." This thesis is dedicated to him, my father; who bestowed upon me the greatest gift of all, an education.
    [Show full text]
  • 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.
    [Show full text]
  • Vysoké Učení Technické V Brně Brno University of Technology
    VYSOKÉ UČENÍ TECHNICKÉ V BRNĚ BRNO UNIVERSITY OF TECHNOLOGY FAKULTA STAVEBNÍ FACULTY OF CIVIL ENGINEERING ÚSTAV TECHNOLOGIE STAVEBNÍCH HMOT A DÍLCŮ INSTITUTE OF TECHNOLOGY OF BUILDING MATERIALS AND COMPONENTS VLIV VLASTNOSTÍ VSTUPNÍCH MATERIÁLŮ NA KVALITU ARCHITEKTONICKÝCH BETONŮ INFLUENCE OF INPUT MATERIALS FOR QUALITY ARCHITECTURAL CONCRETE DIPLOMOVÁ PRÁCE DIPLOMA THESIS AUTOR PRÁCE Bc. Veronika Ondryášová AUTHOR VEDOUCÍ PRÁCE prof. Ing. RUDOLF HELA, CSc. SUPERVISOR BRNO 2018 1 2 3 Abstrakt Diplomová práce se zaměřuje na problematiku vlivu vlastností vstupních surovin pro výrobu kvalitních povrchů architektonických betonů. V úvodní části je popsána definice architektonického betonu a také výhody a nevýhody jeho realizace. V dalších kapitolách jsou uvedeny charakteristiky, dávkování či chemické složení vstupních materiálů. Kromě návrhu receptury je důležitým parametrem pro vytvoření kvalitního povrchu betonu zhutňování, precizní uložení do bednění a následné ošetřování povrchu. Popsány jsou také jednotlivé druhy architektonických betonů, jejich způsob vyrábění s uvedenými příklady na konkrétních realizovaných stavbách. V praktické části byly navrženy 4 receptury, kde se měnil druh nebo dávkování vstupních surovin. Při tvorbě receptur byl důraz kladen především na minimální segregaci čerstvého betonu a omezení vzniku pórů na povrchu ztvrdlého betonu. Klíčová slova Architektonický beton, vstupní suroviny, bednění, separační prostředky, cement, přísady, pigment. Abstract This diploma thesis focuses on the influence of properties of feedstocks for the production of quality surfaces of architectural concrete. The introductory part describes the definition of architectural concrete with the advantages and disadvantages of its implementation. In the following chapters, the characteristics, the dosage or the chemical composition of the input materials are given. Besides the design of the mixture, important parameters for the creation of a quality surface of concrete are compaction, precise placement in formwork and subsequent treatment of the surface.
    [Show full text]
  • The Influence of Ambient Temperature on High Performance Concrete
    materials Article The Influence of Ambient Temperature on High Performance Concrete Properties Alina Kaleta-Jurowska * and Krystian Jurowski Faculty of Civil Engineering and Architecture, Opole University of Technology, Katowicka 48, 45-061 Opole, Poland; [email protected] * Correspondence: [email protected] Received: 2 September 2020; Accepted: 12 October 2020; Published: 18 October 2020 Abstract: This paper presents the results of tests on high performance concrete (HPC) prepared and cured at various ambient temperatures, ranging from 12 ◦C to 30 ◦C (the compressive strength and concrete mix density were also tested at 40 ◦C). Special attention was paid to maintaining the assumed temperature of the mixture components during its preparation and maintaining the assumed curing temperature. The properties of a fresh concrete mixture (consistency, air content, density) and properties of hardened concrete (density, water absorption, depth of water penetration under pressure, compressive strength, and freeze–thaw durability of hardened concrete) were studied. It has been shown that increased temperature (30 ◦C) has a significant effect on loss of workability. The studies used the concrete slump test, the flow table test, and the Vebe test. A decrease in the slump and flow diameter and an increase in the Vebe time were observed. It has been shown that an increase in concrete curing temperature causes an increase in early compressive strength. After 3 days of curing, compared with concrete curing at 20 ◦C, an 18% increase in compressive strength was observed at 40 ◦C, while concrete curing at 12 ◦C had a compressive strength which was 11% lower.
    [Show full text]
  • The Effect of Time on the Workability of Different Fresh Concrete Mixtures in Different Management Conditions
    International Journal of Applied Science and Mathematical Theory ISSN 2489-009X Vol. 2 No.1 2016 www.iiardpub.org The Effect of Time on the Workability of Different Fresh Concrete Mixtures in Different Management Conditions 1Joseph Chukwuka Okah* and 2Okore Godwin 1Department of Building Technology, Rivers State College of Arts and Science, Port Harcourt, Nigeria 2Department of Civil Engineering, Abia State Polytechnic, Aba, Nigeria *Corresponding author Email: [email protected] ABSTRACT Workability can be defined as the amount of useful internal work necessary to produce full compaction. Consistency, mobility and compactability define workability. Factors such as constituent materials and environmental conditions affect workability. Research works has been done on the factors while field work continues to be starved of knowledge of the effect of time after mixing on workability. To this end, this paper presents an investigation into the effect of time on the workability of different fresh concrete mixtures handled differently. To achieve this, a slump test, compacting factor test and the modified Vebe consistometer test was carried out under ambient conditions of 29-300C temperature, 95% relative humidity and less windy condition with 250kg, 350kg, 415kg, 545kg and 560 kg of cement and max. aggregate size of 40mm at w/c ratio of 0.45. The results (curves) show that in 1hr times the loss of workability of the un-agitated mixes was remarkable while the agitated concrete still retains an appreciable workability after 1hr but tends to lose its workability totally in 2½hrs time. It showed that the % loss of workability of un-agitated MX1, MX2, MX3, MX4 and MX5 dropped by 75%, 70%,75%, 66.7% and 68.2% after 1hr against the 43.8%, 40%, 40%, 38% and 40.9% of the agitated concretes respectively by slump test.
    [Show full text]
  • Investigation of Alkali-Silica Reactivity in Sustainable Ultrahigh Performance Concrete
    sustainability Article Investigation of Alkali-Silica Reactivity in Sustainable Ultrahigh Performance Concrete Safeer Abbas 1, Wasim Abbass 1, Moncef L. Nehdi 2,* , Ali Ahmed 1 and Muhammad Yousaf 1 1 Civil Engineering Department, University of Engineering and Technology Lahore, Lahore 54890, Pakistan; [email protected] (S.A.); [email protected] (W.A.); [email protected] (A.A.); [email protected] (M.Y.) 2 Department of Civil and Environmental Engineering, Western University, London, ON N6A 5B9, Canada * Correspondence: [email protected]; Tel.: +1-519-6612111 (ext. 88308) Abstract: Considering its superior engineering properties, ultrahigh performance concrete (UHPC) has emerged as a strong contender to replace normal strength concrete (NSC) in diverse construction applications. While the mechanical properties of UHPC have been thoroughly explored, there is still dearth of studies that quantify the durability of UHPC, especially for sustainable mixtures made with local materials. Therefore, this research aims at investigating the alkali-silica reactivity (ASR) potential in sustainable UHPC in comparison with that of NSC. Sustainable UHPC mixtures were prepared using waste untreated coal ash (CA), raw slag (RS), and locally produced steel fibers. UHPC and benchmark NSC specimens were cast for assessing the compressive strength, flexural strength, and ASR expansion. Specimens were exposed to two curing regimes: accelerated ASR conditions (as per ASTM C1260) and normal water curing. UHPC specimens incorporating RS achieved higher compressive and flexural strengths in comparison with that of identical UHPC specimens made with CA. ASR expansion of control NSC specimens exceeded the ASTM C1260 limits (>0.20% at Citation: Abbas, S.; Abbass, W.; 28 days).
    [Show full text]
  • Physical Properties of Structural Lightweight Concrete
    Chapter 6 Physical Properties of Structural Lightweight Concrete The information present in Chapter 6 and 7 is also covered in a more general way in: ACI 213R-03 “Guide for Structural Lightweight Aggregate Concrete” and ASTM 169 D “Lightweight Concrete and Aggregates” Both are excellent references. April 2007 Expanded Shale, Clay & Slate Institute (ESCSI) 2225 E. Murray Holladay Rd, Suite 102 Salt Lake City, Utah 84117 (801) 272-7070 Fax: (801) 272-3377 [email protected] www.escsi.org 6-1 CHAPTER 6 6.0 Definition of Terms 6.1 Compressive Strength 6.2 Density Density of the Constituents of Concrete Mixtures’ Equilibrium Density-Self Loads Specified Density Concrete 6.3 Absorption 6.4 Internal Curing Introduction 6.5 Contact Zone Implication of Contact Zone on Failure Mechanisms 6.6 Permeability 6.7 Pozzolanic Characteristics History Pozzolanic Terminology and Properties Influence on Properties of Concrete Pozzolanic Reaction in the Contact Zone 6.8 Heat Flow Characteristics Thermal Conductivity Lightweight Concrete High Strength Lightweight Concrete High Strength Specified Density Concrete Specific Heat Thermal Diffusivity 6.9 Fire Resistance General High Strength Lightweight Concrete High Strength Specified Density Concrete 6.10 Refractory Concrete 6.11 Abrasion Resistance Appendix 6A ―Standard Test Method for Determining Density of Structural Lightweight Concrete”, ASTM C 567-05. Appendix 6B “Jet Exhaust Damaged Concrete”, Hronaka and Malvar, Concrete International, October 1998. Appendix 6C Refractory Concrete Papers Appendix 6D ESCSI Publication #4362 ―Internal Curing Using Expanded Shale, Clay and Slate Lightweight Aggregate”. Appendix 6E Chapter 46 ―Lightweight Concrete and Aggregates”, Significance of Tests and Properties of Concrete and Concrete-Making Materials, ASTM Special Technical Publication 169D.
    [Show full text]
  • Properties and Applications of Fiber Reinforced Concrete
    JKAU: Eng. Sci., Vol. 2, pp. 49-6~ (1410 A.H./19lJlI A.D.) Properties and Applications of Fiber Reinforced Concrete FAISAL FOUAD WAFA Associate Professor, Civil Engineering Department, Faculty ofEngineering, King Abdulaziz University, Jeddah, Saudi Arabia. ABSTRACT. Fiber reinforced concrete (FRC) is a new structural material which is gaining increasing importance. Addition of fiber reinforcement in discrete form improves many engineering properties of concrete. Currently, very little research work is being conducted within the King­ dom using this new material. This paper describes the different types of fib­ ers and the application of FRC in different areas. It also presents the result of research about the mechanical properties of FRC using straight as well as hooked steel fibers available in the region, Introduction Concrete is weak in tension and has a brittle character. The concept of using fibers to improve the characteristics of construction materials is very old. Early applications include addition of straw to mud bricks, horse hair to reinforce plaster and asbestos to reinforce pottery. Use of continuous reinforcement in concrete (reinforced con­ crete) increases strength and ductility, but requires careful placement and labour skill. Alternatively, introduction offibers in discrete form in plain or reinforced con­ crete may provide a better solution. The modern development of fiber reinforced concrete (FRC) started in the early sixties(1J. Addition of fibers to concrete makes it a homogeneous and isotropic material. When concrete cracks, the randomly oriented fibers start functioning, arrest crack formation and propagation, and thus improve strength and ductility. The failure modes of FRC are either bond failure be­ tween fiber and matrix or material failure.
    [Show full text]