STSS
Simple Tools Sell Steel

Simple Tools Sell Steel (STSS) STANDARDS
PROBLEM/OPPORTUNITY
• Development of new methods for prediction of performance and characterisation of resistance in design applications for new high strength steels are needed
• Objectives are to remove the cumbersome complexity of the calculation methods and to provide efficient tools
Structural Steel Resistance
New Methods and Tools
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IMS ACTIVITY
• Research, develop and disseminate new calculation methods and tools
Direct Strength Method – Lead
Continuous Strength Method – Lead
Overall Interaction Concept – Lead
Planned project launch March, 2012
PARTICIPANTS
 Major Steel Producers
 Steel Fabricators
 Structural Steel Associations
 Construction Design Engineering Firms
 Structural Steel Research Institutions
 Universities

SSTS - Project Rationale
• In order to use structural steel in buildings, bridges, and any other applications, design engineers must calculate the resistances to ensure design safety.
• Current calculation methods are cumbersome and will not accommodate advances in new materials.
• Because incremental improvements of existing methods will not be successful, this project starts from the perspective of new methods, revolutionary in character, and appropriate for the materials of today and tomorrow.

SSTS – The Big Picture
• The core of this project is the development and assessment of new design methods for steel structures.
• Simple design formulae and application software will be eventually embedded in standards and must therefore anticipate now, the needs of tomorrow
• The developed methods must be able to:
– Calculate the resistance of sections and members
– Include a possible influence of shear stresses
– Offer the possibility to resort to either elastic or plastic analysis
• Common structural steels and non-linear materials
(stainless steel, aluminium) in various cross-sectional shapes, either open or hollow, must be able to be included in the analysis.

STSS Project Business Architecture

STSS Basic Concept
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– Basis: interaction between Resistance and Instability
– Generalizes “relative slenderness” concept to:
• Sections and Members
• Basic loading cases as well as complex ones

SSTS Benefits of Overall Interaction Concept
• Simple, consistent, rational (economic)
• Allows for direct design calculations:
– effective and efficient analytical framework
• Pave the way for tomorrow’s high strength steels
• Removes disadvantages embedded with crosssection classification system
– effective properties, discontinuities, inconsistencies
• Simple application tools to be made available for an efficient and practical use

STSS Project Work Plan
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– Switzerland, Europe, USA, and Korea
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Professor Nicolas Boissonnade
College of Engineering and Architecture
Civil Engineering Department
Fribourg, Switzerland

STSS Project Work Packages
Development of
Practical Tools and Design Formulae
Cross-Sectional and Member
Resistance
I and H-shaped Sections
WP 6 WP 1
Development of
Criteria to allow for Plastic Analysis
WP 5 WP 2
Cross-Sectional and
Member Resistance
Hollow or
Tubular Sections
WP 4 WP 3
Influence of Shear Stresses on Cross-sectional Resistance
Behaviour of Non-linear
Materials, including
Strain Hardening Effects
WP 7 - Incorporation of Design Formulae into Design Standards

STSS Project Work Package One
• Develop and assess the Overall Interaction Concept to provide accurate estimates of the resistance of Open
Sections, for both Sections and Members.
• Lead – Prof. Jean-Pierre Jaspart – University of Liège –
Belgium.
• Confirmed Partners: ArcelorMittal – Luxembourg;
College of Engineering and Architecture of Fribourg,
Johns Hopkins University, Imperial College London;
Technical University of Graz.
• To be invited – Tata Steel, United Kingdom;
AISI/AISC/Nucor – USA; POSCO – Korea.

STSS Project Work Package Two
• Develop and assess the Overall Interaction Concept to provide accurate estimates of the resistance of Hollow Sections, for both Sections and Members.
• Lead – Prof. Nicolas Boissonnade – College of Engineering and
Architecture of Fribourg – Switzerland.
• Confirmed Partners: Voestalpine Krems – Austria; Brütsch-
Ruegger – Switzerland; Stahl Gerlafingen – Switzerland;
University of Liège, Johns Hopkins University, Imperial College
London; Technical University of Graz.
• To be invited – CIDECT; Tata Steel, United Kingdom; Grupo
Condesa, Spain; Vallourec & Mannesmann Tubes, Germany,
POSCO – Korea.

STSS Project Work Package Three
• Extend the scope of the Overall Interaction Concept to include the behaviour of non-linear materials and to benefit from the inclusion of strain hardening effects.
• Lead – Dr Leroy Gardner – Imperial College London – England.
• Confirmed Partners: College of Engineering and Architecture of Fribourg, University of Liège, Johns Hopkins University,
Technical University of Lisbon, Technical University of Graz.
• To be invited – ArcelorMittal – Luxembourg; Tata Steel, United
Kingdom; AISI/AISC/Nucor – USA; POSCO – Korea, CIDECT;
Grupo Condesa, Spain; Vallourec & Mannesmann Tubes,
Germany.

STSS Project Work Package Four
• Include Influence of Shear and/or Torsion Stresses in the Overall
Interaction Concept Resistance Estimates of WP1 and WP2.
• Lead – Prof. Ben Schafer – Johns Hopkins University – Baltimore, USA
• Confirmed Partners: Voestalpine Krems – Austria; Brütsch-Ruegger –
Switzerland; Stahl Gerlafingen – Switzerland; College of Engineering and Architecture of Fribourg, University of Liège, Imperial College
London, Technical University of Lisbon, Virginia Tech (Blacksburg, VA –
USA).
• To be invited – ArcelorMittal – Luxembourg; Tata Steel, United
Kingdom; AISI/AISC/Nucor – USA; POSCO – Korea, CIDECT; Grupo
Condesa, Spain; Vallourec & Mannesmann Tubes, Germany.

STSS Project Work Package Five
• The removal of Classes within the Overall Interaction Concept requires the development of a set of new criteria for Plastic Analysis.
• Lead – Prof. Nicolas Boissonnade – College of Engineering and
Architecture of Fribourg – Switzerland.
• Confirmed Partners: Voestalpine Krems – Austria; Brütsch-Ruegger –
Switzerland; Stahl Gerlafingen – Switzerland; University of Liège,
Imperial College London, Technical University of Lisbon, Technical
University of Graz, Johns Hopkins University, Virginia Tech (Blacksburg,
VA – USA).
• To be invited – ArcelorMittal – Luxembourg; Tata Steel, United
Kingdom; AISI/AISC/Nucor – USA; POSCO – Korea, CIDECT; Grupo
Condesa, Spain; Vallourec & Mannesmann Tubes, Germany.

STSS Project Work Package Six
• Based on the Overall Interaction Concept as developed in WPs 1,2,3, and 4, provide practical tools and design formulae to structural engineers for resistance calculations in project design. These tools and formulae will be prepared in a manner consistent with building codes for ease of promulgation and adoption as national standards.
• Lead – Prof. Dinar Camotin – Technical University of Lisbon – Portugal.
• Confirmed Partners: College of Engineering and Architecture of
Fribourg, University of Liège, Imperial College London, Johns Hopkins
University.
• To be invited – ArcelorMittal – Luxembourg; Tata Steel, United
Kingdom; AISI/AISC/Nucor – USA; POSCO – Korea, CIDECT; Grupo
Condesa, Spain; Vallourec & Mannesmann Tubes, Germany.

STSS Project Work Package Seven
WP 7
- Incorporation of Design Formulae into Design Standards
• The various developed design formulae are developed in a code-ready format, with the intention to see them incorporated in design standards worldwide.
• Lead – Prof. Nicolas Boissonnade – College of
Engineering and Architecture of Fribourg –
Switzerland.
• Confirmed Partners: University of Liège, Imperial
College London, Johns Hopkins University, Virginia
Tech , Technical University of Lisbon, Technical
University of Graz.

STSS Project Timing
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STSS Project Contact Information
• Prof. Dr. Nicolas Boissonnade
• Civil Engineering Department– College of
Engineering and Architecture of Fribourg
• Pérolles 80 – CP 32 – CH-1705 Fribourg
(Switzerland)
• +41 (0)26 429 66 79 (direct)
• +41 (0)26 429 66.11 (central)
• +41 (0)26 429 66.00 (fax)