DOCSLIB.ORG

5.1 Basics of Reinforced Concrete 1

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
5.1 Basics of Reinforced Concrete 1 Section 5 Reinforced Concrete 5.1 Basics of Reinforced Concrete 1 PCA Video, VC114 ’88 Mod ‘07: Fundamentals 3 of Reinforcing and Prestressed Concrete Structural Engineering Concepts 4 Reinforcement Inspection 10 CRSI Video, Mod ‘08: Field Inspection of 11 Reinforcing Bars WCI Video: Jobsite Handling of Epoxy Coated 21 Rebar CRSI: MSP Chp. 8, Placing Reinforcing Bars 22 Bar Supports 24 Bar Ties 27 Clearances 29 Splices 37 Reinforced Concrete Section 5.1 Concrete Cracks Basics of Reinforced Concrete • Concrete is strong in compression and weak in tension. Compression Tension • Tensile capacity is approximately 10% of the compressive strength of concrete. January, 2020 1 Reinforced Concrete Section 5.1 Beam Exercise Basics of Reinforced Concrete Cont’d: • Steel reinforcement is strong in tension. • Reinforcement is added to carry tensile loads in concrete members. • Temperature reinforcement is added to carry tensile loads due to thermal expansion of concrete members. January, 2020 2 Reinforced Concrete Section 5.1 Why Use Rebar? Simply supported beam example Applied Load View PCA Video Fundamentals of Reinforcing and Prestressed Concrete (PCA VC114 ’88 Mod ‘07) January, 2020 3 Reinforced Concrete Section 5.1 Structural Engineering Concepts Shear & Moment Diagram Uniformly Loaded Simple Beam January, 2020 4 Reinforced Concrete Section 5.1 Maximum Shear Load at Bridge Ends and Piers Larger Stirrup Spacing @ Midspan Tighter Stirrup Spacing Near Abutments Tighter Stirrup Spacing at Beam Ends January, 2020 5 Reinforced Concrete Section 5.1 Shear & Moment Diagram Uniformly Loaded Continuous 3 Span Uniformly Loaded Continuous Beam 3 Spans Maximum negative moment in deck over piers. Additional longitudinal reinforcement added in top mat. January, 2020 6 Reinforced Concrete Section 5.1 Beam Capacity Strength of the Beam Beam Cross-section Beam Side View M = Astfy(d-1/2a) = 0.85fc′ab(d-1/2a) January, 2020 7 Reinforced Concrete Section 5.1 Case Study I-25: Walnut Street Denver, CO January, 2020 8 Reinforced Concrete Section 5.1 Thoughts? Deck To Be Placed Later Construction Joint I-25: Walnut Street Pier Collapse January, 2020 9 Reinforced Concrete Section 5.1 Pier Collapse I-25: Walnut Street, Denver, CO Oct. 4, 1985 Fatalities: 1 Injuries: 4 Reinforcement Inspection January, 2020 10 Reinforced Concrete Section 5.1 View CRSI Video CRSI Field Insp Reinf Bars Mod 08 Type of Reinforcement • Source • Certifications • Grade • Epoxy coated or uncoated or stainless January, 2020 11 Reinforced Concrete Section 5.1 Documentation Bills of material – what was delivered Certifications Rebar (steel) mill certificate January, 2020 12 Reinforced Concrete Section 5.1 January, 2020 13 Reinforced Concrete Section 5.1 English Rebar Numbers • #3 - #8; Diameter in 1/8″ units #8/8 = 1″ dia. • #9 - #18; Based on area of square bars formerly used with sides of 1″, 1-1/8″, 1-1/4″, 1-1/2″ & 2″ and then rounded to closest 1/8″ unit diameter. Metric to English Bar Conversion • (Bar # - 1) divided by 3 then round to nearest english bar # • #25 metric = (25-1)/3 = #8 english January, 2020 14 Reinforced Concrete Section 5.1 QPL Appendix A http://www.oregon.gov/ODOT/HWY/CONSTRUCTION/QPL/Docs/QPL.pdf Rebar Exercise Mill: Size: Dia: Type: Grade: January, 2020 15 Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 1 Appendix A—Approved Reinforcing Steel Producers The ASTM specifications for billet-steel and low-alloy reinforcing bars (A615 and A706, respectively) require identification marks to be rolled into the surface of one side of the bar to denote the producer’s mill designation, bar size, type of steel and minimum yield designation. Grade 420 bars show these marks in the following order: 1st ---Producing Mill (usually a letter) 2nd --- Bar Size Number (# 4 through # 18) 3rd --- Type of Steel: S Billet (A 615) W for Low Alloy ( A 706) 4th ---Minimum Yield Designation The minimum yield designation for Grade 420 bars is either one (1) single, longitudinal line (grade line) or the number 4 (grade mark). A grade line is smaller and is located between the two main ribs, which are on opposite sides of all bars made in the United States. A grade line must be continued through at least 5 deformation spaces, and it may be placed on the side of the bar opposite the bar marks. A grade mark is the fourth mark on the bar. VARIATIONS: Bar identification marks may also be oriented to read horizontally (90° to those illustrated). Grade numbers may be placed within consecutive deformation spaces to read vertically or horizontally. The Identification marks for the Approved Producers are shown in the following figures. Rebar grades shown on these pages are for reference only. Check the specs for the appropriate requirements. Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 2 ArcelorMittal Vinton, Inc. El Paso Texas ODOT # 1841 Nucor Steel Utah ODOT # 1112 Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 3 CMC Steel Mesa Arizona ODOT #4118 Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 4 Nucor Steel Seattle Washington ODOT # 2935 Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 5 Optimus Beaumont Texas ODOT #4838 Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 6 CMC Steel California ODOT #1842 Was Gerdau @ Rancho Cucamonga California Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 7 CMC Steel California ODOT #1842 Was Gerdau @ Rancho Cucamonga California Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 8 Gerdau St. Paul Minnesota ODOT # 1623 Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 9 Cascade Steel Mc- Minnville Oregon ODOT # 1111 Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 10 A706/A615 GRADE 60 REBARS MARKINGS Rebar sizes: #3 thru #6 NUCOR STEEL – KINGMAN, AZ ODOT #4356 Current SI Marking New IN-LBS Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 11 EVRAZ INC, NA PUEBLO, COLORADO ODOT #1621 (COILED REBAR #3-#6) Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 12 NUCOR-BAURBONNAIS (KANKAKEE) ODOT #4943 (BAR SIZE #3-#11) Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 13 CMC STEEL-DURANT OKLAHOMA #4-#11 STRAIGHT #3-#6 COILED ODOT #5138 Oregon DOT – QPL (July 2019) Oregon DOT – QPL (July 2019) Attachment “A” Approved Rebar Producers (English Units) Page A 14 ASTM A1035 CS (AAHSTO M334) ChrǀmX 9100 SIZE #3-#8 PRODUCED BY: CASCADE STEEL ROLLING MILLS, INC. ODOT #3517 Oregon DOT – QPL (July 2019) Reinforced Concrete Section 5.1 Rebar Exercise Mill: Size: Dia: Type: Grade: Size & Shape • Bar size • Bar length • Bar shape (correct radius) • Agrees with shop drawings January, 2020 16 Reinforced Concrete Section 5.1 REBAR MATERIAL TAG AB A. Quantity B. Size C C. Bend diagram D. Project D E. Bar ID or mark → Verify E Doubled Up Horizontal Bars in Abutment? January, 2020 17 Reinforced Concrete Section 5.1 Hooked Bar in Middle of Deck by Itself? Rebar Condition January, 2020 18 Reinforced Concrete Section 5.1 Condition • Look for any loose scale or rust, grease, oil, paint, or other foreign material that could harm the bond with the concrete. • Properly stored off the ground to avoid water and mud which can cause corrosion. • Do not use cracked or split bars (look at bends). • Look for epoxy damage. Field Bent Bars? January, 2020 19 Reinforced Concrete Section 5.1 Epoxy Damage Rebar Jobsite Storage Total exposure time of epoxy-coated bar in storage or in place is not to exceed 2 months without covering. (530.40) Epoxy breaks down under prolonged UV exposure – it gets chalky January, 2020 20 Reinforced Concrete Section 5.1 Faded Epoxy & Bare Ties? View WCI Video Jobsite Handling Epoxy Coated Rebar January, 2020 21 Reinforced Concrete Section 5.1 Layout • Number • Spacing • Alignment Placement Tolerances according to “Manual of Standard Practice” 530.41 January, 2020 22 Reinforced Concrete Section 5.1 Effective Depth “d” Distance from the compression face of the beam to the centroid of the reinforcement Transverse Bar Alignment Shift? January, 2020 23 Reinforced Concrete Section 5.1 Longitudinal Bar Alignment Shift? Bar Supports January, 2020 24 Reinforced Concrete Section 5.1 Rail Stirrup Height Uneven? Transverse Deck Bars Drop at Corner? January, 2020 25 Reinforced Concrete Section 5.1 Bar Supports 00530.41(b) & (c) 2′ Centers (plans) Concrete blocks (Dobies) or other approved devices No rocks, broken brick, or wood Bar Supports Plans, General Notes Support the bottom mat reinforcing steel from the forms with precast mortar blocks at 24” max. centers each way. Support the top mat reinforcing steel from the bottom mat reinforcing steel with wire bar supports as shown in Chapter 3 of the CRSI Manual of Standard Practice (SBU, BBU or CHCU). Place wire bar supports at 24” max. centers. January, 2020 26 14871 Contract Plans 195/468 Reinforced Concrete Section 5.1 Large Support Spacing Caused Epoxy Ties to Unzip Ties January, 2020 27 Reinforced Concrete Section 5.1 Top mat of Ties footings & 00530.41(b) decks: Tie 100% Epoxy coated ties for epoxy rebar If spacing < 6″ Tie 50% Other locations: Tie 100% If spacing < 1′ Tie 50% No Ties for Up to 10 Feet? January, 2020 28 Reinforced Concrete Section 5.1 Missing Ties Clearances January, 2020 29 Reinforced Concrete Section 5.1 Concrete Cover Affects Rebar Corrosion Concrete cover Clearances • Within tolerances recommended in CRSI’s Manual of Standard Practice, Chapter 8 unless otherwise specified.
Load more

Recommended publications
  • 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.
    [Show full text]
  • Reinforced Concrete Failure Mechanisms
    Reinforced Concrete Failure Mechanisms Best Practices in Dam and Levee Safety Risk Analyses Part E – Concrete Structures Chapter E-2 Last modified June 2017, Presented July 2019 Reinforced Concrete Failure Mechanisms OUTLINE: • Types of Structures • Spillway Piers • Navigation Lock Walls • Floodwalls • Slabs • Buttresses • Factors influencing strength and stability of reinforced concrete sections • National code requirements in the context of risk • Considerations when determining risk analysis failure probabilities based on structural analysis results • Typical event tree of the progression of failure 2 Reinforced Concrete Failure Mechanisms OBJECTIVES: • Get a broad overview of potential failure modes for different kinds of reinforced concrete structures • Understand the mechanisms that affect reinforced concrete failures • Understand how to construct an event tree to represent reinforced concrete failures • Understand how to estimate event probabilities and probability of breach Reinforced Concrete Failure Mechanisms SUMMARY OF KEY CONCEPTS: • Significant uncertainty for reinforced concrete failure mechanisms under seismic loading due to limited case histories • Concrete and reinforcement material properties can be determined with confidence for dams and floodwalls. • Type and duration of loading is important to understand – consider both static and earthquake loading • Ductile and Brittle Failure mechanisms • Seismic reinforcement details have changed dramatically over the past few decades; older concrete hydraulic structures may be
    [Show full text]
  • 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
    [Show full text]
  • A Computational Study of the Shear Behavior of Reinforced Concrete Beams Affected from Alkali–Silica Reactivity Damage
    materials Article A Computational Study of the Shear Behavior of Reinforced Concrete Beams Affected from Alkali–Silica Reactivity Damage Bora Gencturk 1,* , Hadi Aryan 1, Mohammad Hanifehzadeh 1, Clotilde Chambreuil 2 and Jianqiang Wei 3 1 Sonny Astani Department of Civil and Environmental Engineering, University of Southern California, 3620 S. Vermont Avenue, KAP 210, Los Angeles, CA 90089-2531, USA; [email protected] (H.A.); [email protected] (M.H.) 2 LMT—Laboratoire de Mécanique et Technologie, University Paris-Saclay, ENS Paris-Saclay, CNRS, 91190 Gif-sur-Yvette, France; [email protected] 3 Department of Civil and Environmental Engineering, University of Massachusetts, Lowell, MA 01854-5104, USA; [email protected] * Correspondence: [email protected]; Tel.: +1-(213)-821-1036; Fax: +1-(213)-744-1426 Abstract: In this study, an investigation of the shear behavior of full-scale reinforced concrete (RC) beams affected from alkali–silica reactivity damage is presented. A detailed finite element model (FEM) was developed and validated with data obtained from the experiments using several metrics, including a force–deformation curve, rebar strains, and crack maps and width. The validated FEM was used in a parametric study to investigate the potential impact of alkali–silica reactivity (ASR) degradation on the shear capacity of the beam. Degradations of concrete mechanical properties were correlated with ASR expansion using material test data and implemented in the FEM for Citation: Gencturk, B.; Aryan, H.; different expansions. The finite element (FE) analysis provided a better understanding of the failure Hanifehzadeh, M.; Chambreuil, C.; mechanism of ASR-affected RC beam and degradation in the capacity as a function of the ASR Wei, J.
    [Show full text]
  • 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.
    [Show full text]
  • 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.
    [Show full text]
  • 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.
    [Show full text]
  • Formwork.Pdf
    Formwork INTRODUCTION ............................................................................................................................................................ 3 DESIGN REQUIREMENTS ............................................................................................................................................... 4 FACTORS RELATING TO FORMWORK ........................................................................................................................... 6 HIGH WALL FORMWORK .......................................................................................................................................... 6 Timber Framed Formwork. ....................................................................................................................................... 7 SHEATHING ............................................................................................................................................................... 8 WALL TYING SYSTEMS .............................................................................................................................................. 8 CONSTRUCTION JOINTS ............................................................................................................................................ 9 SLIPFORM ............................................................................................................................................................... 10 CLIMBING OR JUMP FORMS ..................................................................................................................................
    [Show full text]
  • Formation of Polymer Micro-Agglomerations in Ultralow-Binder-Content Composite Based on Lunar Soil Simulant
    Available online at www.sciencedirect.com ScienceDirect Advances in Space Research 61 (2018) 830–836 www.elsevier.com/locate/asr Formation of polymer micro-agglomerations in ultralow-binder-content composite based on lunar soil simulant Tzehan Chen a, Brian J. Chow b, Ying Zhong a, Meng Wang b, Rui Kou b, Yu Qiao a,b,⇑ a Program of Materials Science and Engineering, University of California – San Diego, La Jolla, CA 92093, USA b Department of Structural Engineering, University of California – San Diego, La Jolla, CA 92093-0085, USA Received 9 August 2017; received in revised form 25 October 2017; accepted 27 October 2017 Available online 6 November 2017 Abstract We report results from an experiment on high-pressure compaction of lunar soil simulant (LSS) mixed with 2–5 wt% polymer binder. The LSS grains can be strongly held together, forming an inorganic-organic monolith (IOM) with the flexural strength around 30–40 MPa. The compaction pressure, the number of loadings, the binder content, and the compaction duration are important factors. The LSS-based IOM remains strong from À200 °C to 130 °C, and is quite gas permeable. Ó 2017 COSPAR. Published by Elsevier Ltd. All rights reserved. Keywords: Binder content; Lunar regolith; Structural material; In-situ resource utilization 1. Introduction A major component of lunar soil is silica. While, once heated to above 1200 °C, silica grains can be fused In the next a few decades, building large-scale lunar together, the thermal processing consumes a large amount bases and/or research facilities on the Moon will probably of energy (Taylor and Meek, 2005).
    [Show full text]
  • 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.
    [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]
  • 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.
    [Show full text]