POSSIBLE FUTURE TRENDS IN COLD FORMED STEEL. OBJECTIVES ¥ PREDICTIONS -- RATHER A WISH LIST FOR...

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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

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

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)

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

500000

1000000

1500000

2000000

2500000

RESIDENTIAL MARKET

1994Target 2002

500000

1000000

1500000

2000000

100000

200000

300000

400000

500000

600000

Steel framing, joists, trussesResidential steel roofing1994Target 2002 1994Target 2002

MOTIVATIONS FOR USE OF STEEL STABLE STEEL PRICES VS

FLUCTUATING TIMBER PRICES DWINDLING TIMBER SUPPLIES CONCERN FOR ENVIRONMENT HIGH STRENGTH TO WEIGHT RATIO DURABILITY

50 TREES 6 JUNKED CARS

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

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

SIMPLER APPLICATIONS SUCH AS

RESIDENTIAL BUILDINGS SIMPLER RULES FOR DESIGN AND

MEMBER SELECTION

STANDARDIZED MEMBERS SIMPLIFIED 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

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

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

POSSIBLE FUTURE TRENDS IN COLD FORMED STEEL. OBJECTIVES ¥ PREDICTIONS -- RATHER A WISH LIST FOR...

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