190620-Composite Structures - Introduction (By SNB).pptx
- 1. Composite Structures - Introduction BY, SHASHANK N BABU
- 2. What are Composite Structures? General Any members composed of more than one material. Combination of Steel Concrete. Why? Steel is efficient in tension while concrete is efficient in compression. Uses? Buildings, Bridges
- 3. Major Types COMPOSITE BEAMS - SIMPLY SUPPORTED COMPOSITE BEAMS - CONTINUOUS COMPOSITE COLUMNS COMPOSITE SLABS COMPOSITE JOINTS
- 4. Codes Associated with Design IS 11384 1985 Code of Practice for Composite Construction in Structural Steel and Concrete. This standard deals with the design and construction of Composite beams ( simply supported ) made up of structural steel units and cast in-situ concrete. Eurocode 4: Design of composite steel and concrete structures (2004) EN 1994-1-1 : General rules and rules for buildings EN 1994-1-2 : Structural fire design EN 1994-2 : General rules and rules for bridges
- 5. Advantages Architectural In addition to reductions in the dimensions of the beams longer spans thinner slabs Economical Reduction of height reduces the total height of the building Functionality Big Bonus is Fire Safety, Modern steel and composite structures can provide fire resistance by using principles of reinforced concrete structures in which the concrete protects the steel because of its high mass and relatively low thermal conductivity. (IS Codes do not cover this at all)
- 7. Examples in Real Life Millennium Tower (Vienna - Austria) Citibank Duisburg, Germany
- 8. Examples in Real Life Grand Palladium, Mumbai Eicher Corporate Office, Gurgaon
- 10. Composite Beams (Typical Types) Partially encased SOLID SLABS COMPOSITE SLABS
- 11. Composite Beams (Typical Types) Composite or Non-composite? Design the bare steelwork to carry all the loads Since the 1950卒s it has become increasingly common to connect the concrete slabs to the supporting beams by mechanical devices. Eliminates slip at the steel-concrete interface, so that the slab and the steel beam section act together.
- 12. Main Components of Composite Beam Types of Steel Beam Standard hot rolled section Symmetric or a-symmetric welded section Types of Slab In-situ Concrete Planks or Prefab Plates
- 14. Shear Connectors
- 15. Shear Connectors Headed Stud Connector Hilti Connectors Anchors Block Type Connector
- 18. Shear Connectors - Contd Strength plays a crucial part. Obtained experimentally (Push off or out test) Output Load vs Slip Curve.
- 19. Shear Connectors - Strength fu = 450 N/mm2 (Generally) Strength depends on: Size, height, concrete grade and ultimate stress fu Shear of steel stud Crushing of concrete 留 = 1 for h/d>4 留 = 0.8 for h/d=3
- 20. Shear Connectors - Strength
- 21. Shear Connectors Strength Reduction
- 22. Shear Connectors Strength Reduction Ribs tangential to stud nr is the number of stud connectors in one rib at a beam intersection, not to exceed 2
- 23. Shear Connectors Strength Reduction Ribs parallel to stud nr is the number of stud connectors in one rib at a beam intersection, not to exceed 2 hsc is the overall height of the stud, but not greater than hp + 75 mm
- 24. Simply Supported Beam (Composite) Typical Design Sections for SS Case.
- 25. Max Moment Section I-I Case 1: Neutral Axis in concrete slab. hc be 0.85 fcd = Fc Afy = Fs
- 26. Max Moment Section I-I Case 1: Neutral Axis in concrete slab. hc be 0.85 fcd = Fc Afy = Fs
- 27. Max Moment Section I-I Case 1: Neutral Axis in concrete slab. x = Force Equilibrium hc be 0.85 fcd = Fc Afy = Fs
- 28. Max Moment Section I-I Case 2: Neutral Axis in Steel Flange. Fs > Fc > hw tw fy
- 29. Max Moment Section I-I Case 2: Neutral Axis in Steel Flange. Fs > Fc > hw tw fy
- 30. Max Moment Section I-I Case 3: Neutral Axis in Steel Web. Fc < hw tw fy
- 31. Max Moment Section I-I Case 3: Neutral Axis in Steel Web. Fc < hw tw fy
- 32. Max Long. Shear Section II-II Typical Design Sections for SS Case.
- 33. Max Long. Shear Section II-II Full Shear Connection (2 Cases)
- 34. Next Part Partial Shear Connection Maximum Vertical Shear Design Deflection