Woodson Concrete Portable Handbook

1. Auflage 2011
ISBN: 978-0-12-382177-5
Verlag: Elsevier Science & Techn.
Format: EPUB
Kopierschutz: 6 - ePub Watermark

E-Book, Englisch, 480 Seiten

Whether or not, you are on the job site or back in the office, this book will help you to avoid mistakes, code violations, and wasted time and money. The book's four part treatment begins with constituent materials followed by self contained parts on Concrete Properties, Processes, and Concrete Repair and Rehabilitation. Designed to be an 'all in one' reference, the author includes a wealth information for the most popular types of testing. This includes: Analysis of Fresh Concrete; Testing Machines; Accelerated Testing Methods; Analysis of Hardened Concrete and Mortar; Core Sampling and Testing; Assessment of Concrete Construction ; Repair; Quality Concepts; Quality Control; Statistics; Standards, Specifications, and Codes of Practice. With this book in hand, construction engineers and even technicians find valuable information regarding Exposed Concrete Finishes, Repairing Concrete, Formwork, Precast Concrete, Concrete Roads, and Industrial Floors. Project managers and owners will find this reference a valuable guide to concrete both in terms of its applications in construction projects and the science and chemistry of concrete for its own sake. - Fundamentals of Concrete Chemistry - Handy at your figure tip calculations - Tips for working with all types of concretes - Covers Roads, floors, and finishes - Principles of Precast, Reinforced and Prestressed Concrete

Autoren/Hrsg.

Woodson, R. Dodge

Inhaltsverzeichnis

1;Front Cover;1
2;Concrete Portable Handbook;2
3;Copyright;3
4;Table of Contents;8
5;Acknowledgments;12
6;About the Author;14
7;Introduction;16
8;Chapter
1. Basic Information;18
8.1;Paperwork;18
8.2;Inspection;19
8.3;Special Considerations;20
9;Chapter 2. Concrete Materials;22
9.1;Aggregates;33
9.2;Water;33
9.3;Steel Reinforcement;34
9.4;Admixtures;34
9.5;Storage of Materials;35
10;Chapter
3. Durability and Protection;36
10.1;Special Exposure Conditions;36
10.2;Corrosion Protection;38
11;Chapter
4. Mixing and Placing Concrete;40
11.1;Average Compressive Strength;40
11.2;Site Preparation;42
11.3;Mixing Concrete;43
11.4;Depositing Concrete;51
11.5;Curing;54
11.6;Weather Conditions;55
12;Chapter 5. Concrete Formwork;58
12.1;Form Removal;58
12.2;Embedded Items;60
12.3;Construction Joints;61
12.4;Pre-Formed Concrete Products;61
13;Chapter 6. Reinforcement;64
13.1;Standard Hooks;64
13.2;Condition of Reinforcement Materials;65
13.3;Reinforcement Spacing;65
13.4;Bundling Bars;65
13.5;How Much Coverage Is Needed?;67
13.6;Column Support;67
13.7;Some Spiral Facts;69
13.8;Ties;69
13.9;Structural Integrity;69
14;Chapter 7. General Design Consideration;70
14.1;Analysis;70
14.2;Length of Spans;71
14.3;Columns;71
14.4;Live Load Assumptions;72
14.5;T-Beam Construction;72
14.6;Joist Construction;73
14.7;Finished Flooring;74
15;Chapter
8. Requirements for Strength and Serviceability;76
15.1;Design Strength;78
15.2;Complicated Calculations;78
15.3;Local Practices;79
15.4;Common Sense;79
16;Chapter
9. Inspecting In-Place Concrete;82
16.1;Plans and Specs;83
16.2;Judging the Site;83
16.3;Quality of Installation;83
16.4;Cracked Concrete;84
16.5;Crack Activity;87
16.6;Crack Occurrence;87
16.7;Disintegration;88
16.8;Scaling;88
16.9;Dusting;89
16.10;Distortion;89
16.11;Erosion;89
16.12;Seal Failure;90
16.13;Special Cases of Spalling;90
16.14;Delamination;91
16.15;Crack Surveys;91
16.16;Sizing Cracks;91
16.17;Mapping;92
16.18;Joint Inspections;93
16.19;Core Drilling;93
16.20;Underwater Concrete;93
16.21;High-Resolution Acoustic Mapping System;95
16.22;Side Scanner;95
16.23;Other Means of Underwater Testing;96
16.24;Laboratory Work;97
16.25;Chemical Analysis;97
16.26;Physical Analysis;97
16.27;Nondestructive Testing;97
16.28;Other Considerations;99
17;Chapter
10. Concrete Failure;100
17.1;Unintentional Loads;100
17.2;Chemical Reactions;101
17.3;Corrosion;106
17.4;Freezing and Thawing;108
17.5;Settlement and Movement;108
17.6;Shrinkage;109
17.7;Fluctuations in Temperature;110
18;Chapter
11. Concrete Repair Preparation;112
18.1;Compressive Strength;112
18.2;Modulus of Elasticity;113
18.3;Thermal Expansion;113
18.4;Bonding;113
18.5;Drying Shrinkage;113
18.6;Creep;115
18.7;Permeability;115
18.8;Planning a Repair;116
18.9;Manufacturer’s Data;119
19;Chapter
12. Removal and Repair;120
19.1;Removal Methods;121
19.2;Blasting;121
19.3;Crushing;122
19.4;Cutting;122
19.5;Impacting Methods;123
19.6;Boom-Mounted Concrete Breakers;123
19.7;Spring-Action Hammers;123
19.8;Hand-Held Impact Breakers;124
19.9;Hydromilling;124
19.10;Rotary-Head Milling;124
19.11;Pre-Splitting;124
19.12;Chemical Agents;125
19.13;Piston-Jack Splitters;125
19.14;Plug-Feather Splitter;125
19.15;Prep Work;125
19.16;Reinforcing Steel;127
19.17;Anchors;127
20;Chapter
13. Rehabilitation Work;130
20.1;Prestressing Steel;131
20.2;Autogenous Healing;131
20.3;Conventional Placement;132
20.4;Crack Arrest Techniques;135
20.5;Drilling and Plugging;135
20.6;Drypacking;136
20.7;Fiber-Reinforced Concrete;138
20.8;Flexible Sealing;139
20.9;Gravity Soak;140
20.10;Chemical Grouting;141
20.11;Hydraulic-Cement Grouting;141
20.12;High-Strength Concrete;141
20.13;Jacketing;142
20.14;Judicious Neglect;142
20.15;Polymer Overlays;142
20.16;Polymer Coatings;143
20.17;Polymer Concrete;144
20.18;Polymer Impregnation;144
20.19;Polymer Injection;144
20.20;Pre-Cast Concrete;146
20.21;Preplaced-Aggregate Concrete;147
20.22;Rapid-Hardening Cement;147
20.23;Roller-Compacted Concrete;147
20.24;Routing and Sealing;147
20.25;Shotcrete;148
20.26;Shrinkage-Compensating Concrete;148
21;Chapter 14. Maintenance Matters;150
21.1;Stains;150
21.2;Stain Removal;152
21.3;Cleaning Details;152
21.4;Coatings and Sealing Compounds;155
22;Chapter
15. Specialized Repairs;156
22.1;Rehabbing Lock Walls;156
22.2;Cast-in-Place;157
22.3;Blasting Lock Walls;157
22.4;Anchors;159
22.5;Concrete Placement;159
22.6;Shotcrete;160
22.7;Preplaced-Aggregate Concrete;160
22.8;Pre-Cast Concrete;160
22.9;Cutoff Walls;161
22.10;Pre-Cast Concrete Applications;161
22.11;Underwater Repairs;162
22.12;Geomembrane Work;164
22.13;Roller-Compacted Concrete;164
23;Chapter 16. Problem Solving;166
23.1;Bad Design Data;167
23.2;Chemical Attack;167
23.3;Alkali–Aggregate Reaction;167
23.4;Freezing;168
23.5;Moving Water;168
23.6;Cavitation;168
23.7;The Roundup;168
24;Chapter
17. Code Requirements;170
24.1;Concrete Selection;170
24.2;Compressive Strength;171
24.3;Field-Cured Specimens;171
24.4;Putting Concrete in Place;172
24.5;Mixing Concrete;172
24.6;Placing Concrete;173
24.7;Curing;173
24.8;Form Design;173
24.9;Form Removal;174
24.10;Embedded Items;174
24.11;Construction Joints;175
24.12;Reinforcement;175
24.13;Column Reinforcement;176
24.14;Connections;176
24.15;Spirals;177
24.16;Ties;177
24.17;Shrinkage;178
24.18;Structural Integrity Requirements;178
24.19;Live Loads;178
24.20;T-Beams;179
24.21;Joist Construction;179
24.22;First Step;179
25;Chapter 18. How Much Do You Know?;182
25.1;True or False Quiz;182
25.2;Multiple-Choice Questions;184
25.3;Correct Answers for True–False Questions;187
25.4;Correct Answers for Multiple-Choice Questions;187
26;Chapter 19. Working with Code Requirements;188
26.1;Lax Jobs;188
26.2;Strict Code Enforcement;189
26.3;Safety;189
26.4;Fees;189
26.5;Know Your Inspectors;190
26.6;Local Jurisdictions;190
26.7;Common Sense;190
27;Chapter
20. Avoiding On-the-Job Injuries;192
27.1;Very Dangerous;192
27.2;General Safety;194
27.3;Clothing;195
27.4;Jewelry;196
27.5;Eye and Ear Protection;196
27.6;Pads;196
27.7;Tool Safety;197
27.8;Power Mixers;198
27.9;Co-Worker Safety;200
28;Chapter
21. Worksite Survival;202
28.1;Open Wounds;203
28.2;Splinters and Foreign Objects;205
28.3;Eye Injuries;206
28.4;Scalp Injuries;206
28.5;Facial Injuries;207
28.6;Nose Bleeds;207
28.7;Back Injuries;207
28.8;Legs and Feet;208
28.9;Hand Injuries;208
28.10;Shock;208
28.11;Checklist of Shock Symptoms;209
28.12;Burns;210
28.13;Heat-Related Problems;211
29;Appendix I. Background Facts and Issues Concerning Cement and Cement Data;212
30;Appendix II. Concrete Pavement Technology Update;302
31;Appendix III. Foundry Sand Facts for Civil Engineers;316
32;Appendix IV. Increasing the Quality of Concrete and Concrete Related Products;396
33;Appendix V. Concrete and Masonry Construction;420
33.1;Contents;421
33.2;What Does OSHA’s Concrete and Masonry Standard Cover?;422
33.3;What Are the Key, New Changes to the Standard?;423
33.4;What Are the Components of the New Standard?;423
33.5;What Are the General Requirements of the Standard?;423
33.6;What Are the Requirements for Cast-in-Place Concrete?;424
33.7;What Other Help Can OSHA Provide?;428
33.8;Glossary;430
33.9;OSHA-Related Publications;430
33.10;States with Approved Plans;431
33.11;OSHA Consultation Project Directory;435
33.12;OSHA Area Offices;437
33.13;OSHA Regional Offices;440
34;Appendix VI. Glossary of Abbreviations;444
35;Appendix VII. Common Definitions;448
36;Appendix VIII. Industry Resources;454
37;Glossary;460
38;Index;466

Leseproben

Chapter 2

Concrete Materials

Publisher Summary

This chapter presents an overview of Portland cement and concrete. Portland cement is a general term used to describe a variety of cements. Because they are hydraulic cements, they will set and harden by reacting chemically with water through hydration. Hydraulic cements are the binding agents in concretes and most mortars and are thus common and critically important construction materials. Hydraulic cements are of two broad types: those that are inherently hydraulic, and those that are pozzolanic. Portland cement is the most commonly manufactured and used hydraulic cement in the United States and the world. It is manufactured through the blending of mineral raw materials at high temperatures in cement rotary kilns. Rotary kilns produce an intermediate product called “clinker.” Clinker is ground to produce cement. Portland cement manufacturing is a two-step process beginning with the manufacture of clinker followed by the fine grinding of the clinker with gypsum and other additives to make the finished cement product. Grinding can occur on site or at offsite grinding plants. The U.S. Geological Survey (USGS) estimated that in 2005 approximately 97.5 million metric tons (Mt) of Portland plus masonry cement was produced at 113 plants in 37 states in the United States.

admixture; aggregates; ASTM standards; cement; cementitious material; concrete; fly ash; non-potable water; Portland cement; pozzolans; steel reinforcement

Outline

Aggregates 16

Water 16

Steel Reinforcement 17

Admixtures 17

Storage of Materials 18

Concrete materials are a key element in concrete construction and an in-depth discussion is presented in this chapter. An exhibit titled Overview of Portland Cement and Concrete outlines the uses and make up of Portland cement and other types of building materials. Aggregates, types of water used to mix with the concrete, steel reinforcement, and admixtures and their ASTM standards are all discussed. The chapters ends with instructions for storing these materials.

Concrete materials are obviously a key element in concrete construction, and building officials have the power to require testing of any of these concrete materials. The purpose of this testing is to ensure that all of the materials meet the quality specified when applying for a permit. The results of these tests are generally required to be available for review for at least two years after construction is completed.

When it comes to discussing approved types of cement, specifications and standards will come from the American Standard Testing Methods (ASTM).

Exhibit: Overview of Portland Cement and Concrete

Overview of Portland Cement and Concrete

Although the terms “cement” and “concrete” are often used interchangeably, cement is actually an ingredient of concrete. Cements are binding agents in concretes and mortars. Concrete is an artificial rock-like material, basically a mixture of coarse aggregate (gravel or crushed stone), fine aggregate (sand), cement, air, and water. Portland cement is a general term used to describe a variety of cements. Because they are hydraulic cements, they will set and harden by reacting chemically with water through hydration.

Current (2004) world total annual production of hydraulic cement is about 2 billion metric tons (Gt), with production spread unevenly among more than 150 countries. This quantity of cement is sufficient for about 14–18 Gt/year of concrete (including mortars), and makes concrete the most abundant of all manufactured solid materials. The current yearly output of hydraulic cement is sufficient to make about 2.5 metric tons per year (t/year) of concrete for every person worldwide (van Oss, 2005).

Cement and Cement Manufacturing

Hydraulic cements are the binding agents in concretes and most mortars and are thus common and critically important construction materials. Hydraulic cements are of two broad types: those that are inherently hydraulic (i.e., require only the addition of water to activate), and those that are pozzolanic. The term pozzolan (or pozzolanic) refers to any siliceous material that develops hydraulic cementitious properties in the presence of lime [Ca(OH)2]. This includes true pozzolans and latent cements. The difference between these materials is that true pozzolans have no cementitious properties in the absence of lime, whereas latent cements already have some cementitious properties, but these properties are enhanced in the presence of lime. Pozzolanic additives or extenders can be collectively termed supplementary cementitious materials (SCM; van Oss, 2005).

Portland cement is the most commonly manufactured and used hydraulic cement in the United States (and the world). It is manufactured through the blending of mineral raw materials at high temperatures in cement rotary kilns. Rotary kilns produce an intermediate product called “clinker.” Clinker is ground to produce cement. By modifying the raw material mix and, to some degree, the temperature of manufacture, slight compositional variations in the clinker can be achieved to produce Portland cements with varying properties.

Similar varieties of Portland cement are made in many parts of the world but go by different names. In the United States, the different varieties of straight Portland cement are denoted per the ASTM Standard C-150 as:

• Type I: general use Portland cement. In some countries, this type is known as ordinary Portland cement.

• Type II: General use Portland cement exhibiting moderate sulfate resistance and moderate heat of hydration.

• Type III: High-early-strength Portland cement.

• Type IV: Portland cement with low-heat hydration.

• Type V: Portland cement with high sulfate resistance.

For Types I, II, and III, the addition of the suffix A (e.g., Type IA) indicates the inclusion of an air-entraining agent. Air-entraining agents impart a myriad of tiny bubbles into the concrete containing the hydrated cement. This offers certain advantages to the concrete, such as improved resistance to freeze-thaw cracking. In practice, many companies market hybrid Portland cements; Type I/II is a common hybrid that meets the specifications of both Types I and II. Another common hybrid is Type II/V.

Blended Cements

Blended cements (called composite cements in some countries) are intimate mixes of a Portland cement base (generally Type I) with one or more SCM extenders. The SCMs make up about 5–30% by weight of the total blend, but can be higher.

In blended cements, the SCMs (or pozzolans) are activated by the high pH resulting from the hydroxide ions released during the hydration of Portland cement. The most commonly used SCMs are volcanic ashes called pozzolana, certain types of fly ash (from coal-fired power plants), ground-granulated, blast-furnace slag (GGBFS) — now increasingly being referred to as slag cement — burned clays, silica fume, and cement kiln dust (CKD). In general, incorporation of SCMs with Portland cement improves the resistance of the concrete to chemical attack, reduces the concrete’s porosity, reduces the heat of hydration of the cement (not always an advantage), potentially improves the flowability of concrete, and produces a concrete having about the same long-term strength as straight Portland cement-based concretes. However, SCMs generally reduce the early strength of the concrete, which may be detrimental to certain applications (van Oss, 2005).

Blended cements can be prepared at a cement plant for sale as a finished blended cement product or can be blended into a concrete mix. Most of the SCM consumption by U.S. concrete producers is material purchased directly for blending into the concrete mix. Concrete producers in the United States buy relatively little finished blended cement.

The designations for blended cements vary worldwide, but those currently in use in the United States meet ASTM Standard C-595, C 989, or C-l 157. ASTM Standard C-595 defines several types of blended cements. The main designations include (van Oss, 2005):

• Portland blast-furnace slag cement (IS): Contains 25–70% GGBFS.

• Portland-pozzolan cement (IP and P): Contains a base of Portland and/or IS cement and 15–40% pozzolans.

• Pozzolan-modified Portland cement (I(PM)): The base is Portland and/or Type IS cement with a pozzolan addition of less than 15%.

• Slag-modified Portland cement (I(SM)): Contains less than 25% GGBFS.

• Slag cement (S):1 GGBFS content of 70% or more. Type S can be blended with Portland cement to make concrete or with lime for mortars; the latter combination would make the final cement a pozzolan-lime cement.

Chemical Composition of Portland Cement

Modern straight Portland cement is a very finely ground mix of Portland cement clinker and a small amount (typically 3–7%) of gypsum (calcium sulfate dihydrate) and/or anhydrite (calcium sulfate). Cement chemistry is generally denoted in simple stoichiometric shorthand terms for the major constituent oxides....