Technical Training Basics: What is truss
Technical Training Basics: What is truss. Goal of this workshop . Share knowledge Actively promote safe working practices Provide product expertise for users. Topics. What is truss Differ ent forces on Truss Analising loading of truss structures Truss standards Questions.
Technical Training Basics: What is truss
E N D
Presentation Transcript
Goal of this workshop • Share knowledge • Actively promote safe working practices • Provide product expertise for users
Topics • What is truss • Different forces on Truss • Analising loading of truss structures • Truss standards • Questions
What is truss ? • Lattice structure • Made of (mainly) aluminium tubes • Low self weight (easy to handle ) • Modular (easy to transport) • Flexible (lego system)
What is a lattice structure? • A lattice structure is an open triangular structure. • Triangular shapes are stable in hinged connections • Triangulation is essential for strength and stability
The Truss Cross bracing bracing End bracing Main tube Coupling system Node point
Why is Truss made of (mainly) aluminium? Advantages of aluminium • +/- 1/3 of the weight of steel • Non corrosive • Available in large quantities • Easy to machine • Allowable stress for tension and compression is the same
Why is Truss made of (mainly) aluminium? Disadvantages of aluminium • Strength decreases after welding with +/- 50% • Less stiff as steel • More difficult to weld • More expensive
Main advantage of a Truss structure : Low self weight in relation to a high load bearing capacity. Achieved by.. Bringing the material to the position where you need it !!!!!
Different type’s of coupling systems • Tube coupler • Gusset / Endplate • Hinge connection Male / Female • Conical coupler
1: Tube connection-Very high bearing stress in the main chord-Open space between main chord.
2: Gusset / Endplate-Bending force in gusset Plate-Open space between main chord
3: Hinge connection Male / Female-Fixed Male/Female sides wear given extra deflexion
Mounting different brands of truss together. • Although the truss looks the same each type of truss has different technical specifications • Calculation of the system with different specifications. • Responsibility
Different forces on Truss • Loading Forces • Internal reaction Forces
Different type’s of loading • Point load • Multiple point load • Concentrated load • Uniformly distributed load • Cantilever load • Normal force
Internal reaction forces in the Truss • Bending moment • Transversal forces ( also known as shear force ) • Normal forces • Torsion force • The reaction of these forces is • Deflection
This figure indicates where the internal forces are active in the truss. Normal force Shear force Normal force Bending moment Normal force
Bending moment To strain under tension, causing a straight line structure to turn into a curve-shape
Examples of situations when a bending moment occurs: • Self weight caused by the Force of gravity • Live loading such as lightning fixture or Sound equipment • Curtains, back drapes • Wind force.
