This document provides an overview of a teaching primer on steel structures for colleges of architecture. It includes sections on the material facts of steel, its chemical composition and production processes. There are also sections on the structural properties and terminology used in steel construction, as well as profiles commonly used in steel structures. The document contains introductory slides and acknowledges contributions from various organizations and individuals.
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Project Director
Slide Design & Graphics
Production Assistants
IT Coordination
Photography
Software
For additional information,
please contact:
College of Architecture,
UNC-Charlotte
PRODUCTION TEAM College of Architecture
UNC - Charlotte
CREDITSThe Material Steel |
David Thaddeus, AIA, Associate Professor
Thaddeus@email.uncc.edu
David Thaddeus, AIA
Jennifer August
Brittany Eaker
Kathy Phillips
Matt Parker
David Thaddeus, AIA
Nate Robb
PowerPoint
Photoshop
Deborah J. Arbes, RA
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This project was made possible through funding from the American Institute of Steel Construction (AISC)
with support from the College of Architecture at the University of North Carolina at Charlotte
Special thanks to the following people at AISC for their support and help over the duration of the project:
Fromy Rosenberg, PE, Director, AISC University Programs
Megan Maurer, Coordinator, AISC University Programs
The following people have my sincere gratitude for serving on the Focus Group and offering their
comments and feedback in the development of this project :
Kurt Baumgartner, AIA, JIA, University of Illinois at Urbana Champaign
Terri Meyer Boake, Associate Professor, University of Waterloo
Thomas Fowler, Associate Professor, California Polytechnic State University
Harry Kaufman, PE, NCARB, Professor, Southern Polytechnic State University
Kemp Mooney, Kemp Mooney Architects
Tim Mrozowski, AIA, Professor, Michigan State University
Ryan Smith, Assistant Professor, University of Utah
The following AISC members have provided invaluable insight into the content of this teaching aid:
Ron Bruce, PE, President, Builders Steel Company, North Kansas City, MO
Lawrence Kruth, PE, Engineering & Safety Manager, Douglas Steel, Lansing, MI
David McKenzie, PE, Vice President - Engineering, SP International, North Kansas City, MO
Acknowledgements
ACKNOWLEDGEMENTSThe Material Steel |
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The American Institute of Steel Construction (AISC) is a non-profit technical
institute and trade association established in 1921 to serve the structural steel
design community and construction industry in the United States.
AISC is offering this teaching aid and learning tool for educational purposes only.
The data and information in this presentation is not intended for use in the
physical construction of steel structures.
The information presented here is considered public information and as such may
be distributed or copied. The use of appropriate credit to for images, byline,
animations, and content is requested.
We hope that you and your students will find this information useful.
Please contact Fromy Rosenberg (rosenberg@aisc.org) for further information
on AISC or for feedback on this teaching / learning product.
Please contact David Thaddeus (thaddeus@email.uncc.edu) for questions or
comments on the content of this project.
Terms
TERMSThe Material Steel |
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The Material Facts
Chemical Composition
Production
Structural Properties
Terminology
Profiles in Steel
Protection of Steel Members
Appropriate Technology / Sustainability of Steel
Module I
Contents:
Overview
CONTENTS
CONTENTSThe Material Steel |
Clinical Sciences Research,
Stanford University . Palo Alto, California
Sir Norman Foster
The de Menil Collection Museum
Houston, Texas
Renzo Piano
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STRUCTUREOFTHEEVERYDAYSTEEL Steel | The Material Facts
Today steel is produced in over 50 countries all across the world.
In 2003, China was the first country to produce more than 200 million tons of crude
steel in a year (more than 20% of the world’s steel is produced in China).
China is the world’s largest consumer of steel (cars, general industry, construction…)
Japan is the largest exporter of steel.
More than 60% of the steel produced annually is from recycled steel.
Properties of steel are not altered by how many times it is recycled.
Per pound of material, steel is the most efficient of all building materials.
A small amount of steel can do load-carrying tasks with a fraction of the material
needed from other materials such as concrete or wood.
Steel is the densest of structural materials and therefore handles longer spans,
and produces lighter structures with the greatest economy.
Steel can be found in fasteners (nails…), structural components, rebar,
sheet-metal, appliances, cars, ships, …
To every ton of Portland Cement produced, 3 tons of wood and 10 tons of steel
are produced.
The United States and China are the largest importers of steel.
British Inventor Henry Bessemer produced the first economical steel in 1856.
Steel is the world’s most recycled material. Steel is recycled mostly from junk cars
(3-400,000 cars per year per steel mill; 27 cars / minute in North America ).
THE MATERIAL FACTS
Steel was first produced in 1738 in Sheffield, England, know as “crucible steel”
in was very pure, but difficult and expensive to produce.
The Material Steel |
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Steel is an alloy of Iron, Carbon (<2%), and Manganese (<1%).
It also contains small amounts of Phosphorous, Silicon,
Sulfur and Oxygen
Carbon content greatly affects the properties of steel
More Carbon increases : strength, hardness, corrosion-resistance
More Carbon decreases : malleability, ductility, and weldability
The amount of Carbon does NOT affect the Modulus of Elasticity (E)
of the Steel
Stainless Steel
Adding 15-18% Chromium and 7-8% Nickel produces
corrosion-resistant steelCor-Ten Steel Sculpture
By Richard Serra
Museum of Modern Art
Fort Worth, TX
Weathering Steel (Cor-Ten Steel)
Adding Copper and Phosphorous creates a steel that forms an oxide coating,
rust, that adheres to the base metal and prevents further corrosion
Steel | Chemical Composition
these chemical elements are controlled
to provide consistent quality and grade of steel
Carbon Steel
is Carbon Steel to which one or more chemical
elements have been added to achieve certain physical or chemical
properties
Alloy Steel
CHEMICAL COMPOSITIONModule 1 |
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STRUCTUREOFTHEEVERYDAYSTEEL Steel | Production
Open Hearth Furnace (OHF)
Basic Oxygen Furnace (BOF)
Electric Arc Furnace (EAF)
Refining is the addition of alloys to obtain certain characteristics
in the steel:
U.S. has roughly 25% of world coal supply.
Steel is heated to molten state to remove oxides
Three Types of Production Furnaces:
Iron ore constitutes 5% of earth’s crust, 70% of earth’s core is iron.
Molybdenum- strength.
Manganese- resistance to abrasion and impact.
Vanadium- strength and toughness.
Nickel and chromium- toughness, stiffness and corrosion resistance.
Electric Arc Furnace (EAF) process is environmentally safer.
Casting: Liquid steel is cast into semi-finished products; billet, blooms
By 1980s computer controls were prevalent in steel mills.
Whether BOF or EAF all steel is recycled back into steel, so although
BOF has a lower % of recycled steel, it is still as environmentally friendly.
PRODUCTIONThe Material Steel |
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Open Hearth Furnace (OHF):
Discontinued in USA due to OSHA and EPA regulations,
it wasted energy and manpower.
Last Open Hearth Furnace in U.S. was closed down in 1980s.
Extreme heat burned out impurities in iron.
Accepts variable amounts of scraps (20-80%) .
3000°F minimum temperature required, 10 hours to accomplish.
Worldwide, 3.6% of steel produced in 2003 was OHF.
PRODUCTIONThe Material Steel |
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Steel | Structural Properties
Ductile, absorbs energy
Quick erection.
Flexibility, Strength, Durability, Functionality.
Steel is a lightweight solution that is
strong enough to allow for longer spans.
Steel buildings are light and therefore require
smaller foundations than heavier building materials.
Less time on construction site reduces cost.
Shop Fabrication reduces on-site work down to
the assembly and the erection of frame only.
Shop Fabrication reduces on-site weather delays.
The Material Steel | STRUCTURAL PROPERTIES
Charles de Gaulle Airport
Paris . France
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Structural
Properties:
Overview
Steel is consistent, isotropic and homogenous.
Density 490 LBS./ FT 3
or 0.25 LB. / IN 3
(concrete: 144 LBS./ FT 3
or 0.08 LB./ IN 3
,
wood: 35 - 40 LBS. / FT 3
)
Steel is capable of precise tolerances and with proper
detailing will provide an exceptionally tight building
envelope.
Minimum on-site waste.
Strong and stiff for very little weight.
The Material Steel | STRUCTURAL PROPERTIES
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Architecturally Exposed Structural Steel lends itself naturally
to sustainable building.
AESS avoids additional finishes and, therefore, saves
the energy which would have been used to produce
and transport those finishes.
Using steel whenever possible increases the amount
of recyclable content in building.
Using Bolted connections vs. Welded
makes disassembly / re-use easier.
The integration of structural and mechanical components
which is facilitated by AESS can save building materials.
Besides being structural, Hollow Steel Sections (HSS)
can also convey hot water and therefore contribute to the
heating or plumbing of the building.
The finish color used on the AESS system can enhance
reflectance, reducing lighting and thus saving A/C.
Use of steel and glass atria for natural light (a design
feature common in AESS buildings) can also reduce the
demand for artificial lighting and in turn A/C demand.
The high visibility of an AESS system demands a very
high level of attention to the detailing of the steel members,
their finishes and their connections.
TERMINOLOGYThe Material Steel |
Architecturally Exposed Structural Steel (AESS)
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RemarksApplicationsName Features /
Strengths
Sample Designation Size Range
W 12 x 50 Bending
Compression
Beams
Columns
3/8”< tf < 2”
1/4”< tw < 5”
Wide Flange 12 : Nominal depth
50 : Weight / Lin. Ft.
W 4 – W 44
9 #/ft – 30 #/ft
M-Shapes M 14 x 18 14 : Nominal depth
18 : Weight / Lin. Ft.
M 5-M 14
4.4-18 #/ft
Bending Beams
Columns
Smaller
members
that are
not W,
HP, S
HP 14 x 102 Compression
Bearing
Piles tw = tf < 1”14 : Nominal depth
102 : Weight / Lin.Ft.
HP 8 – HP 14
36 - 117 #/ft
Bearing Piles
S 15 x 50
Bending
Beams
Columns
Flanges
slope at 2:12
Not as
stable as
W-shapes
15 : Nominal Depth
50 : Weight / Lin. Ft.
S 3 - S 24
5.7 - 121 #/ft
American
Standard
(I-beam)
PROFILES IN STEELThe Material Steel |
Steel | Profiles in Steel
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STRUCTUREOFTHEEVERYDAYSTEEL RemarksApplicationsName Features /
Strengths
Sample Designation Size Range
C 10 x 30
Bracing
Lintels
Stairs
Trusses
Nominal
Depth =
Actual Depth
No torsional
strength
10: Actual depth
30: Weight / Lin. Ft.
C3 - C15
4.1 - 50 #/ft
American
Standard
Channel
Tension
Compression
Bending
Miscellaneous
Channels
MC 13 x 50 13: Actual depth
50: Weight / Lin. Ft.
MC 6-18
6.5 - 58 #/ft
PROFILES IN STEELThe Material Steel |
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STRUCTUREOFTHEEVERYDAYSTEEL RemarksApplicationsName Features /
Strengths
Sample Designation Size Range
WT 5 x 9.5
MT 5 x 4.5
ST 5 x 12.7
Compression
Tension
Bending
Bracing
Trusses
Lintels
Split W
-shape
lengthwise
Structural Tees: 5: Nominal depth
9.5, 4.5, 12.7:
Weight/Linear Ft.
WT2 - WT18;
4.5 - 179.5 #/ft
MT2.5 – MT7;
2.2 - 9.45 #/ft
ST1.5 – ST12;
2.85 - 60.5 #/ft
Equal
Leg Angle
L 4 x 4 x 1/2 4 : Leg size
½”: Leg thickness
L 1 x 1 x 1/8-
L 8 x 8 x 1 1/8
Compression
Tension
Bending
Bracing
Trusses
Lintels
Connections
t = 1/8” –
t = 1- 1/8”Unequal
Leg Angle
L 6 x 4 x 1/2 6: Long leg
4: Short leg
½”: Leg thickness
L 2 1/2 x 2 x 3/16
- L 9 x 4 x 5/8
PROFILES IN STEELThe Material Steel |
Cut from W
Cut from M
Cut from S
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Pipes
RemarksApplicationsName Features /
Strengths
Sample Designation Size Range
Stable
Good in
Torsion
Columns
Trusses
Braces
Compression
Tension
20” side
12” side
5/8” thickness
4 x 4 x 1/2 4” each side
½” thickness
2 x 2 x 3/16 –
8 x 8 x 5/8
t: 3/16” - 5/8”
Columns
Trusses
Braces
Rectangular 20 x 12 x 5/8
Square
Stable
Good in
Torsion
Columns
Trusses
Braces
Compression
Tension
½” -12” diameter
½” -12” diameter
2 ”- 8” diameter
Standard
Extra Strong
Double Extra
Strong
Compression
Tension
PROFILES IN STEELThe Material Steel |
3 x 2 x 3/16 –
20 x 12 x 5/84
t: 3/16” - 5/8”
6” Φ Extra
.
Strong
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Objective:
To maintain structural integrity for a specified
period of time to allow the evacuation of
occupants and secure access for firefighters.
Steel | Fire Protection
Fire resistance is expressed in units of time it takes
the structural member to reach failure by heating.
Steel loses its integrity at 500°C (~930°F), and
most of its strength at 600°C (1100°F).
Lighter steel sections will require more fire protection
than thicker sections since heavier sections will heat
up at a slower rate.
Steel sections that are in contact with concrete take
longer to heat up than ones without contact.
The thickness of fire protection material dictates its
fire rating and the protection time it delivers.
Light gauge steel products heat up very quickly.
FIRE PROTECTIONThe Material Steel |
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Minimum fire-resistance ratings for primary and
secondary structural members is provided in
Building Codes and is based on Occupancy and
Type of Construction.
The total area and weight of a building determines
its Building Type.
Most multi-story steel frames are Type I or
Type II - non combustible.
Primary structural members include: columns,
beams, girders, trusses and other structural
members directly connected to columns.
Steel that is to be fire protected should not be painted or
galvanized in order to adhere straight to the base metal.
Fire protection systems are determined by appearance,
durability, cost, ease of installation, finish quality, surface
preparation needed, and speed of application.
Most fire protection systems can provide
up to 4 hours (non-combustible) including
intumescent paints.
FIRE PROTECTIONThe Material Steel |
Charles de Gaulle Airport
Paris . France
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STRUCTUREOFTHEEVERYDAYSTEEL Cost
(Relative)
Care must be
taken to
achieve even
application
Surface
Preparation
Material QualityAppearanceInformation Installation Fire
Rating
Applied to
unpainted
steel
$$
to
$$$
May be used
exposed
Overspray
Can be
troweled
Not typically
aesthetically
acceptable in
public areas
Easy to cover
complex
areas/details
Must mask
adjacent
areas
Very Messy
Interferes with
other trades
$
increasing
thickness
adds
durability
but also
weight
FIRE PROTECTIONThe Material Steel |
Sprayed Fire Resistant Materials (SFRM) | Two Types: Reactive and Non-Reactive
Thin-film
Intumescent
Paint
Epoxy Base
Intumescent
Industrial
Application
&
Provides
insulation by
expanding and
providing “char”
of low heat
conductivity
Kicks in at
200°-250°,
way before
steel starts
to fail
Thickness:
0.03” – 0.4”
Epoxy Base
Up to 1” thick
&
Mineral Fiber
(Dry)
Cementitious
(Wet)
SPRAYED
Non-reactive
Reactive Thin coat
allows steel
profile to
retain detail
and remain
aesthetically
pleasing
attractive
decorative
finishes are
available
Epoxy Base
has course
texture
Brush or
spray applied.
Easy to cover
detail (around
pipes, etc.)
Easy to repair
Wet trade
Must have
proper
atmosphere
conditions at
time of
application
Overspray
must be
considered
Limited fire-
protection
duration
Steel
preparation
may be
necessary
Up to
1 Hr.
(standard)
Can
achieve
4 Hrs.,
but is
costly
Thicker
= more
passes
= more
cost
Up to
4 hrs.
1 hr.
per inch
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STRUCTUREOFTHEEVERYDAYSTEEL Cost
(Relative)
Surface
Preparation
Material QualityAppearanceInformation Installation Fire
Rating
FIRE PROTECTIONThe Material Steel |
Blanket
Insulation
Concrete
Encasing
Unsightly
(needs to be
hidden)
Dry. No effect
on other
trades
$
Less popular
today with the
introduction
of lighter fire
protection
materials
Same as
concrete or
concrete
block
construction
lost space
due to
massiveness
$$$ Unsurpassed
Durability
Non-reactive Uniform
thickness
Applied to
unfinished steel
varies
with
thick-
ness
Applied to
unfinished steel
Typical
construction
methods
adds
significant
weight to the
structure
Weatherability
1-2
Hrs.
Non-reactive Acceptable
Clean, boxed
appearance
can be left
unfinished in
unseen areas
or finished
where visible
Dry
(no wet mess)
Difficult in
small / detailed
areas.
Slower than
some other
methods
Uniform
thickness
assures
the quality
of the rating
Typical for
columns
less usual
for beams
Applied to
unfinished steel
$$
½” =
1 hr.
Up to
4 Hrs.
Gypsum
Board
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STRUCTUREOFTHEEVERYDAYSTEEL Additional Fireproofing Methods
Water and antifreeze for Hollow Steel Section (HSS)
Metal flame shields.
Filling HSS with concrete increases their compressive ability while also providing fire protection.
- Plain concrete fill (1-2 hours), steel yields after 20-30 minutes, then concrete
takes over, concrete can only last so long, then cracks and collapses.
- Adding steel fiber to concrete (2-3 hours) helps carry compression loads longer.
- Adding rebar (2-3 hours).
FIRE PROTECTIONThe Material Steel |
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Plain steel corrodes quickly in moist environments.
Corrosion of steel does not occur if relative humidity
<60%; at 70% relative humidity corrosion is accelerated.
Corrosion (oxidation) is an electrochemical reaction that
oxidizes the iron in steel, commonly called rust.
This makes the steel look unsightly.
It eventually makes steel thinner, vulnerable to water infiltration,
it spalls, loses its structural strength, gradually disintegrates,
and ultimately fails.
When a metal oxidizes, it reverts to its natural, lower energy state.
Zinc is a less noble metal than steel, but corrodes at a slower rate.
CORROSION PROTECTION
Steel | Corrosion Protection
Objective:
To protect structural integrity from the
environmental forces, which act over time,
to deteriorate the individual members of the system.
The Material Steel |
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STRUCTUREOFTHEEVERYDAYSTEEL Internal Alloying
Involves altering the composition of the steel alloy to include nickel, chromium and other
corrosion resistant elements.
This results in stainless steel or weathering steel (weathering steel forms a tight
oxide layer that adheres to the base metal and protects it).
This method of protection (internal alloying) is more expensive than painting or
metallic coating.
CORROSION PROTECTIONThe Material Steel |
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STRUCTUREOFTHEEVERYDAYSTEEL Barrier Protection
Paint
Is a barrier protection system.
Not impervious to moisture infiltration.
Scratches and thus loses its protection ability.
Weather conditions affect application.
Metal Coating: Zinc, Aluminum (anodizing)
Cheap, easy to apply by dipping (easy to coat
details), maintenance free.
Barrier protection system that is impermeable.
Metallic zinc coating has good adhesion to
base metal, abrasion and corrosion resistance.
Zinc is a reactive material which will eventually
corrode and erode away.
CORROSION PROTECTIONThe Material Steel |
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Galvanized protection is proportional to its
thickness and corrosion rate.
Steel is protected by the sacrificial corrosion
of the zinc layer ( 1/10 the rate of steel
corrosion).
If scratched, adjacent steel will not corrode.
Twice the coating thickness will result in twice
the protection.
Amount of protection also depends on the
environment in which the steel will be used
(industrial atmospheres, marine, soil, near
chemicals…).
Galvanizing is done in a factory where quality
is consistent and work is independent of the
weather.
CORROSION PROTECTIONThe Material Steel |
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Surface Preparation and Hot-Dipping:
Surface preparation is essential for
any barrier protection to be effective.
Steel surface may be prepared by:
Caustic cleaning - removes organic
contaminants such as dirt, oil, etc
by dipping in a hot alkali solution.
Pickling - removes scale and rust
by dipping in an acid solution.
Fluxing - removes oxides and
prevents further oxidation.
If surface is not clean, zinc will not
metallurgically react with the steel.
Unclean areas will come out uncoated
from hot-dip process.
CORROSION PROTECTIONThe Material Steel |
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Hot dipping involves complete immersion of
member in 98% molten (840°F) zinc.
The molten zinc reacts with steel to form a
series of alloy layers.
Members are entirely coated on all surfaces
including all details.
Hot-dip galvanizing metallurgically binds the
zinc coating to the base metal and provides
protection from corrosive environments.
Hot-dip galvanizing of hollow steel sections
(tubes and pipes) will coat both inside and
outside allowing indoor / outdoor use.
CORROSION PROTECTIONThe Material Steel |
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STRUCTUREOFTHEEVERYDAYSTEEL
Steel is the most recycled product in the world.
Changes in the processes of steel production
have reduced energy demands. The use of
continuous casting eliminates energy demands
for re-heat treatment of steel.
Steel buildings and other products are
consistently salvaged and recycled.
Concrete is crushed and used as road fill;
rebar is recycled.
Although steel is locally manufactured, not all
raw ingredients for B.O.F. are locally extracted.
Four R’s of sustainability:
Reduce, Re-use, Recycle, and Restore.
Steel producers are constantly striving to reduce
emissions into air and water, and in general to soften
the impact on the world environment.
SUSTAINABILITY
Steel | Sustainability
The Material Steel |
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Recycling steel is done for economic reasons in addition to the environmental benefits.
Most steel products (cars, appliances, bridges, buildings…) have longevity of use and
so there is a shortage of steel to recycle.
Since the supply of steel for recycling is less than demand, raw materials for B.O.F.
continue to be mined.
SUSTAINABILITYThe Material Steel |
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Once a steel appliance is melted down,
it may find new life as a steel column, a
can of soup, a car, or an appliance again.
Environmental efficiency of materials
is analyzed according to the LEED
performance standard or embodied
energy (life cycle inventory) approach
(cradle to grave and cradle to cradle).
Efficiency of material recycling can be
measured either by recycled content
or reclamation rate (number of times
it is recycled).
Magnetic properties of steel permit easy
separation from other building materials
after demolition.
SUSTAINABILITYThe Material Steel |
The De Menil Collection Museum . Houston, Texas
Renzo Piano
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STRUCTUREOFTHEEVERYDAYSTEEL
The North American steel industry has been recycling steel scrap for 150 years through
1800 scrap processors and 12000 auto-dismantling facilities.
Whether B.O.F. or E.A.F. product, steel is recycled into other steel.
Steel products have an endless life through infinite recovery cycles without losing
workability or strength and so may be a perfect application of “cradle to cradle” concept.
Re-using steel could be through disassembly for later re-assembly, or through re-use
on another project or through re-melting in a furnace.
SUSTAINABILITYThe Material Steel |
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Steel that is to be re-used may be tested
for yield strength or carbon content.
Chemical tests are also used to verify
the weld-ability of recycled steel.
Through the use of smaller and lighter
members for longer spans than other
materials, steel will reduce the building
section and thus the sizes of mechanical
systems needed.
SUSTAINABILITYThe Material Steel |
Clinical Sciences Research, Stanford University . Palo Alto, California
Sir Norman Foster
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STRUCTUREOFTHEEVERYDAYSTEEL
In some instances, using a steel frame instead
of a concrete frame will result in half the dead
load and half the foundation weight.
Steel is a green building product.
In general, it is often more economical to salvage
a building rather than sending it to the landfill.
Steel industry accounts for 6% (approximately
45 Billion M Watts) of total electrical energy
consumption in U.S.
SUSTAINABILITYThe Material Steel |
Since 1999, construction of all new federal facilities
must apply sustainable design principles.
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Recycling Facts and Figures
70 Million tons of steel recycled annually.
60% of which was derived from
construction.
400 Million tons worldwide.
1.5 x all other recycled material.
1 ton recycled steel saves:
2500 lbs iron ore
1400 lbs coal
120 lbs limestone
LEED:
Commercial construction produces
2-2.5 lbs solid waste / sq.ft. in demolition.
This may be recycled or re-used.
SUSTAINABILITYThe Material Steel |
Nasher Sculpture Center . Dallas, Texas
Peter Walker, Landscape Architect
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STRUCTUREOFTHEEVERYDAYSTEEL Improved Production Methods
Early Recycling Processes: 100 tons of raw material yielded 60 tons steel.
Current Recycling Processes: 100 tons of raw material yielded 90 tons steel.
B.O.F. 25-35% scraps. E.A.F. 90 -100% scraps.
In 2003: 60.2% steel cans, 102.8% cars, 89.7% appliances,
96% structural steel members, 60% rebar were recycled.
Total 70.7% of all steel products are recycled.
In U.S. most structural shapes and rebars are produced in E.A.F.
HSS are produced in B.O.F.
SUSTAINABILITYThe Material Steel |
Cy Twombly Gallery
Houston, Texas
Renzo Piano
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STRUCTUREOFTHEEVERYDAYSTEEL
USGBC - US Green Building Council
LEED - Leadership in Energy and Environmental Design
LEED is a performance, not a descriptive standard.
Most widely used green building rating in U.S.
69 possible points
Platinum 52+
Gold 39-51
Silver 33-38
Certified 26-32
(not much cost in securing ‘Certified’ level)
SUSTAINABILITYThe Material Steel |
Nasher Sculpture Center
Dallas, Texas
Renzo Piano
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STRUCTUREOFTHEEVERYDAYSTEEL LEED Core Categories
SUSTAINABILITYThe Material Steel |
Clinical Sciences Research,
Stanford University . Palo Alto, California
Sir Norman Foster
• Sustainable Sites 14
credits possible
Local ecology, near public transport,
reduction of
commuting by car.
• Water Efficiency 5
credits possible
Buildings account for 1/6 fresh water
consumption
water efficient fixtures reduce this
amount.
• Energy and Atmosphere
17 credits possible
Renewable and green power
sources.
• Materials and Resources
13 credits possible
Conserve raw materials and
resources (fossil fuels)
Steel contributes most to this
category.
• Indoor Environmental Quality
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STRUCTUREOFTHEEVERYDAYSTEEL LEED Core Categories
SUSTAINABILITYThe Material Steel |
Clinical Sciences Research,
Stanford University . Palo Alto, California
Sir Norman Foster
Sustainable Sites - 14 credits possible
Local ecology, near public transport, reduction of
commuting by car.
Water Efficiency - 5 credits possible
Buildings account for 1/6 fresh water
consumption
water efficient fixtures reduce this
amount.
Energy and Atmosphere - 17 credits
possible
Renewable and green power
sources.
Materials and Resources - 13
credits possible
Conserve raw materials and
resources (fossil fuels)
Steel contributes most to this
category.
Indoor Environmental Quality - 15
credits possible
Air quality, thermal comfort, daylight.
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STRUCTUREOFTHEEVERYDAYSTEEL
Materials and Resources
2: Building Re-use
Conservation of existing resource,
no environmental impacts from transportation,
steel buildings more likely than others for re-use,
easy and cheap retro fits for adaptive re-use.
Encourages use of existing materials over new materials
saves cost of added manufacturing energy
High recycled content.
Materials to be manufactured within 500 miles of fabricator.
Raw materials extracted within 500 miles of site (fabricator).
SUSTAINABILITYThe Material Steel |
The Clark Center, Stanford University
Palo Alto, California
Sir Norman Foster