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POSSIBLE FUTURE POSSIBLE FUTURE TRENDS IN COLD FORMED TRENDS IN COLD FORMED
STEELSTEEL
OBJECTIVESOBJECTIVES
PREDICTIONS -- RATHER A WISH LIST FOR DEVELOPMENTS
HOPEFULLY TO STIMULATE DISCUSSION AND THINKING
SOME PREDICTIONS FOR THE NEAR AND DISTANT FUTURE
“I THINK THERE IS A WORLD MARKET FOR
MAYBE FIVE COMPUTERS,”THOMAS WATSON,
CHAIRMAN OF IBM, 1943
“THERE IS NO REASON ANYONE WOULD WANTA COMPUTER IN THEIR HOME,” KEN OLSON, PRESIDENT, CHAIRMAN AND FOUNDER OF
DIGITAL EQUIPMENT CORP., 1977
COLD-FORMED STEEL COLD-FORMED STEEL PREDICTIONS LESS PREDICTIONS LESS
SPECULATIVESPECULATIVE
STEEL HAS BEEN AROUND FOR A LONG TIME
IRON AGE STARTED ABOUT 700 B. C.
COLD-ROLLING STEEL GOES BACK ABOUT 120 YEARS
APPLICATIONS IN PRINCIPLE SIMILAR TO THOSE 50 YEARS AGO
POSSIBLE FUTURE POSSIBLE FUTURE DEVELOPMENT TOPICSDEVELOPMENT TOPICS
MATERIALS FORMING TECHNIQUES CONNECTIONS APPLICATIONS CONSTRUCTION ENGINEERING AND
SPECIFICATIONS
MATERIALSMATERIALS
TREND TOWARD HIGHER STRENGTH
MATERIALSMATERIALS
LAMINATES TO IMPROVE : STRENGTH REDUCE WEIGHT ACOUSTIC PERFORMANCE
MATERIALSMATERIALS
30% INCREASE IN ELASTIC MODULUS TRANSVERSE TO ROLLING DIRECTION
ADVERSE EFFECTS IN LONGITUDINAL EFFECTS
MATERIALSMATERIALS
ADJUST YIELD TO ULTIMATE RATIOS (BETTER EARTHQUAKE RESISTANCE)
MATERIALSMATERIALS
BETTER CORROSION RESISTANCE INCREASED USE OF STAINLESS
STEELS 12% Cr STEELS (NO NICKEL)
BEING USED IN JAPAN IN HOUSING– SURFACE NOT SHINY, SOME RUST
BUT AT MUCH SLOWER RATE
MATERIALSMATERIALS
BETTER FIRE RESISTANT STEELS - LESS CREEP WHEN SUBJECTED TO
HEAT
CF TECHNIQUES - CF TECHNIQUES - HYBRID SECTIONSHYBRID SECTIONS
higher yieldstress flange seamed and
clinched
lower yieldstress web
CF TECHNIQUES - WEB CF TECHNIQUES - WEB STIFFENERSSTIFFENERS
Embossed websCold worked weband flanges
CF TECHNIQUESCF TECHNIQUES
EXPANDED USE OF AUTOMATIC FABRICATION LINES, SUCH AS
FOR TRUSSES, WALL SUBASSEMBLIES
CF TECHNIQUESCF TECHNIQUES
INCREASED USE OF ROLLING COMBINED WITH HIGH
FREQUENCY WELDING IN ONE OPERATION
CF TECHNIQUESCF TECHNIQUESINCREASED USE CUTTING
AND SEAMING ON PARTS OF SECTIONS TO FACILITATE
CONNECTIONS (NON-PRISMATIC SECTIONS)
CF TECHNIQUESCF TECHNIQUES
CONNECTIONSCONNECTIONS
REPLACEMENT OF LIGHTER HOT-REPLACEMENT OF LIGHTER HOT-ROLLED STEEL MEMBERS WITH COLD ROLLED STEEL MEMBERS WITH COLD
ROLLED STEEL MEMBERSROLLED STEEL MEMBERS
APPLICATIONS - APPLICATIONS - HOUSINGHOUSING
US ANNUAL CONSTRUCTION $415 BILLION.
ABOUT $165 BILLION, OF THIS IS IN THE RESIDENTIAL
POTENTIAL FOR STEEL IN THE ANNUAL 8.4 MILLION TONS.
NOTE: AUTOMOBILE INDUSTRY USES 3.5 MILLION TONS.
APPLICATIONS - HOUSINGAPPLICATIONS - HOUSING
0
500000
1000000
1500000
2000000
2500000
RESIDENTIAL MARKET
48
5.0
00
48
5.0
00
2.3
50
.00
0
1994Target 2002
APPLICATIONS - HOUSINGAPPLICATIONS - HOUSING
0
500000
1000000
1500000
2000000
0
100000
200000
300000
400000
500000
600000
16
5.0
00
16
5.0
00
1.8
00
.00
01
.80
0.0
00
22
0.0
00
22
0.0
00
55
0.0
00
55
0.0
00
Steel framing, joists, trussesResidential steel roofing1994Target 2002 1994Target 2002
APPLICATIONS - HOUSINGAPPLICATIONS - HOUSING
MOTIVATIONS FOR USE OF STEEL STABLE STEEL PRICES VS
FLUCTUATING TIMBER PRICES DWINDLING TIMBER SUPPLIES CONCERN FOR ENVIRONMENT HIGH STRENGTH TO WEIGHT RATIO DURABILITY
APPLICATIONS - HOUSINGAPPLICATIONS - HOUSING
50 TREES 6 JUNKED CARS
APPLICATIONS - HOUSINGAPPLICATIONS - HOUSING
APPLICATIONS - HOUSINGAPPLICATIONS - HOUSING
An old idea whose time appears to have come
Steel alone or in combination with other materials - a suitable material for residential applications
Worldwide interest and development
CONSTRUCTION
WORKERS LESS SKILLFUL MANAGERS MORE EDUCATED BUT
NOT FROM THE TRADE CONSTRUCTION MORE TECHNICAL
BUT SIMPLER TO PUT TOGETHER
CONSTRUCTION
THREE DIMENTIONAL DRAWINGS AND VIRTUAL REALITY TO REPLACE DRAWINGS IN THE FIELD
MORE OF THE STRUCTURES TO BE PRODUCED IN FACTORIES AND ASSEMBLED IN THE FIELD
TOUCH MEMORYTOUCH MEMORY
TOUCH MEMORYTOUCH MEMORY
DRAWINGS OF ASSEMBLY ATTACHED TO THE MEMBER
LIMITATIONS OF USE ATTACHED TO THE STRUCTURES - FOR EXAMPLE: RACK FOR A CERTAIN CONFIGURATION OR EARTHQUAKE ZONE
MANY OTHER USES
ENGINEERING AND SPECIFICATIONS
EFFORTS TO IMPROVE SPECS SIMPLER APPLICATIONS SUCH AS RESIDENTIAL BUILDINGS
COMPLEX HIGHLY OPTIMIZED APPLICATIONS
UNIFICATION OF HR AND CR SPECS
ENGINEERING AND SPECIFICATIONS
SIMPLER APPLICATIONS SUCH AS
RESIDENTIAL BUILDINGS SIMPLER RULES FOR DESIGN AND
MEMBER SELECTION
STANDARDIZED MEMBERS SIMPLIFIED SPECIFICATIONS
ENGINEERING AND SPECIFICATIONS
COMPLEX SHAPES REQUIRE COMPLEX
ENGINEERING ANALYSIS AND DESIGN
USE OF FINITE ELEMENT AND OTHER TYPES
OF COMPUTER ANALYSIS WILL INCREASE
GREATLY AND WILL BE ACCEPTED WIDELY
ENGINEERING AND SPECIFICATIONS
SPECS NEED TO ACCEPT COMPUTER ANALYSIS TO CALCULATE CRITICAL STRESSES TO CALCULATE ULTIMATE LOADS
SPECS TO REFLECT FABRICATION TOLERANCES, IMPERFECTIONS, MATERIAL PROPERTIES, RESIDUAL STRESSES
COMPUTER PROGRAM ACCEPTANCE
GUIDELINES NEEDED
PRESENT EFFECTIVE PRESENT EFFECTIVE SECTION APPROACHSECTION APPROACH
M S fn AISI eff y
b be
PROPOSED DIRECT PROPOSED DIRECT STRENGTH APPROACHSTRENGTH APPROACH
KEY TO THE FUTUREKEY TO THE FUTURE
POSSIBILITIES LIMITED ONLY BY OUR
IMAGINATION
DEVELOPMENTS WILL NOT HAPPEN WITHOUT
ENGINEERING
INDUSTRY MUST PROVIDE LONGER TERM
VISION
RESEARCHERS MUST WORK WITH THE
INDUSTRY
CONCLUSIONSCONCLUSIONS
DWINDLING TIMBER SUPPLIES
RECYCLABLE ENVIRONMENTALLY FRIENDLY
MATERIAL
POSSIBILITIES FOR OPTIMIZATION
ROLLNG THICKER SHEETS - REPLACE MORE
HOT-ROLLED APPLICATIONS
INCLUDE COMPUTER SOLUTIONS IN SPECS