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Olli Ilveskoski

METNET International workshopVilnius, LithuaniaWednesday 13th and Thursday 14th March

BRACING OF MULTIPLE STRUCTURES

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Olli Ilveskoski

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Olli Ilveskoski

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Olli Ilveskoski

FASTNER STRENGHTSSTIFFENESS VALUES ?

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Olli Ilveskoski

FastenersSelf-drilling:• for hot-rolled structure (walls' thickness – 3-12 mm),• for cold-bent structure (thickness – 1.5-5 mm).Note: fasteners are available in galvanized or lacquered -white versions. On special demand it is possible to providehoods or fasteners in external facing colour of a sandwichpanel.

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Olli Ilveskoski

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Olli Ilveskoski

BEAM BUCKLING FLOW CHART

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Olli Ilveskoski

COLUMN BUCKLING FLOW CHART

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Olli Ilveskoski

BUCKLING RESTRAINT FORCE FLOW CHART

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Olli Ilveskoski

SECTION CLASS

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Olli Ilveskoski

RESISTANCES

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Olli Ilveskoski

RESISTANCES

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Olli Ilveskoski

BUCKLING RESISTANCE

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Olli Ilveskoski

RESTRAINT SEGMENTS

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Olli Ilveskoski

(3)B At each plastic hinge location, the connection (e.g. bolts) of the compression flange to the resisting element at that point (e.g. purlin), and any intermediate element (e.g. diagonal brace) should be designed to resist a local force equal to 2,5% of Nf,Ed (defined in 6.3.5.2(5)B) transmitted by the flange in its plane and perpendicular to the web plane, without any combination with other loads.

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Olli Ilveskoski

NO RESTRAINT CONNECTION STIFFNESS REQUIREMENT IN EUROCODE ?

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Olli Ilveskoski

CHENG & JURA / AISC: RESTRAINT STIFFNESS REQUIREMENT

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Olli Ilveskoski

CONCLUSION: BEAM BUCKLING RESULTS

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Olli Ilveskoski

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Olli Ilveskoski

COLUMN BUCKLING RESISTANCES

Nrdy = 709 kN stronger direction

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Olli Ilveskoski

COLUMN BUCKLING RESISTANCES

Nbrdz = 453 kN weaker direction, Buckling restraint segment 2m, ifno restraints Nbrdz = 155 kN < Ned

BUCKLING TAKES PLACE !

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Olli Ilveskoski

INTERACTION FORMULAS

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Olli Ilveskoski

COLUMN’S BRACING CONNECTION FORCES AND CONNECTION STIFFENESS REQUIREMENTS ?

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Olli Ilveskoski

COLUMN DESIGN RESULTS CONNECTION FORCES AND CONNECTION STIFFENESS REQUIREMENTS ?SANDWHICH PANEL BRACING ?

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Olli Ilveskoski

CONNECTION STIFFENESS REQUIREMENT

CONNECTION STIFFENESS VALUE

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Olli Ilveskoski

CONNECTION STIFFNESS REQUIREMENT / NODAL RESTRAINTKortesmaa / VTT

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Olli Ilveskoski

FOR N EQUALLY SPACED BRACES RECOMMENDED STIFFNESSCheng & Jura

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Olli Ilveskoski

CONNECTION STIFFNESS REQUIREMENT / CONTINUOS RESTRAINTCheng & Jura

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Olli Ilveskoski

CONCLUSIONS:

BRACING DESIGN REQUIRES A TOTAL APPROACH

BEAM / COLUMN BRACING RESTRAINT FORCES AND STIFFENESS VALUES MISS COMMON PRACTISE ?

CONNECTION STIFFNESS PLAYS A ROLE ?

BRACING WITH SANDWHICH – PANELS ?

FASTNER’S STIFFNESS PROPERTIES ?

AVERAGE DESIGNER NEEDS MORE CLEAR TOOLS