Post on 17-Dec-2015
transcript
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UTILIZING STEEL PLATE SHEAR WALLS FOR SEISMIC HAZARD
MITIGATION
NASA CIPAIR Summer Internship
By: Agustin Robles, Cham Htun, David Alvarez, and Jasmine Flores
Advisor: Dr. Cheng Chen
Student Advisor: James Enright
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Presentation Outline• Introduction to Steel Plate Shear Walls
• Background information on building and location
• Design calculations• ASCE 7-10 Equivalent Lateral Force Procedure• AISC Code Provisions
• Analysis of structure • SAP2000 lateral force simulations
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Steel Plate Shear Wall Frames• A SPSW frame has three main components:
• Advantages of SPSW:• High plastic energy dissipation• Enhanced stiffness, strength and ductility• Cost efficient
HBE
VB
E
Steel
Plate
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Problem Statement
• Design the optimal member sizes for the:
• Steel plates
• Horizontal boundary elements (HBEs)
• Vertical boundary elements (VBEs)
• Utilize SAP2000 to simulate and evaluate
the structures response to lateral forces.
Design a 3-story office building located at 1300 Market Street, San Francisco, CA 94103. Utilize steel plate shear walls (SPSWs) as the lateral force resisting system.
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Floor psf Height
Floor 3: 95
Floor 2: 90
Floor 1: 92
Total length: 150
Total width: 120
Total floor area: 13,740
Total weight: 3,806
Building Specifications
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Earthquake Probability in the Bay Area
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Equivalent Lateral Force Procedure
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Vertical Distribution of Lateral Forces
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Max Story Drift
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• Determine preliminary sizes for the three main components of the Lateral System• SPSW• HBE• VBE
AISC Seismic Code Provisions
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• The Strip-model was used to approximate SPSW response to lateral forces
• Solving for the angle of inclination, α
• 3rd : α =41.3°• 2nd : α =39.3°• 1st : α =38.3°
AISC Seismic Code Provisions
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• Demand Capacity Ratios (DCR)• Ratio of forces acting on a member with respect to the maximum strength or
capacity of that member• Shear Capacity
• Combined compression and flexure check
AISC Seismic Code Provisions
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• Final member sizes • 2nd floor steel plate redesigned• 3rd and 2nd floor HBE redesigned
• Final design
AISC Seismic Code Provisions
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SAP2000 Analysis of Structure
Building Drift: Inelastic building roof drift
5.35 in
Maximum allowable building drift
10.8 in
Roof drift over building height %
1.2 %
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SAP2000 Analysis of Structure
Moment Axial forces Shear forces
• Figures of forces acting on the structure
Moment Axial forces Shear forces
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SAP2000 Analysis of Structure
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Future Work/ Conclusion• Future/Current Work• Better approximation of the fundamental period
of the structure• Designing the HBEs and VBEs to withstand
some of the shear forces
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Any Questions?