Steel Plate Shear Wall Design - SEAoT

8/12/2012Capacity Design of VBECapacity Design of VBEImportance ofCapacity DesignFlexibility Limit Issue• Lubell et al. (2000)observed poorbehavior of someSPSWs (pull-in ofcolumns)• Others suggestedflexibility limitdesirable to preventslender VBEsSPSW-4 UBC Test (Lubell et al. 2000)SPSW-2 UBC Test (Lubell et al. 2000)Flexibility Limit (cont’d)• Plate girder analogyInfill PanelInfill PanelSteel Plate Shear Wallwhere ω = 0.7htsi4twi2I LStiffnerL• Flexibility factorxuoαuηuI-Beam Plate GirderFlange can be modeled as a continuousbeam on elastic foundationPlate Girder⎛ ⎛ωt ⎞ ⎛ωt ⎞ ⎛ωt ⎞ ⎛ωt⎞⎞sin cosh cos sinhεgL⎜ ⎜2⎟ ⎜2⎟+⎜2⎟ ⎜2⎟⎟( ηu− ηo) = ⎜1−⎝ ⎠ ⎝ ⎠ ⎝ ⎠ ⎝ ⎠⎟max 2sin α ⎜ ⎛ωt ⎞ ⎛ωt ⎞ ⎛ωt ⎞ ⎛ωt⎞sin cos + sinh cosh⎟⎜ ⎜2⎟ ⎜2⎟ ⎜2⎟ ⎜2⎟⎟⎝ ⎝ ⎠ ⎝ ⎠ ⎝ ⎠ ⎝ ⎠⎠cFlangeηoohsδVxessIncrease in streFlexibility Limit (cont’d)1.00.90.807 0.70.60.50.40.30.20.10.0UBC SPSW-2 and SPSW-4: ωt= 3.35Other specimensthat behaved well:ωt≤ 2.520%0 0.5 1 1.5 2 2.5 3 3.5 4ω tEmpirically basedflexibility limit:ω =tSolvingtwi0.7hsi4 ≤2.52ILc40.00307t wihIsic≥LIntroduced in theCAN/CSA S16-01 and2005 AISC SeismicProvisions5