Presentation

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1
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
2
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
3
Steel Plate Shear Wall Frames
• A SPSW frame has three main components:
VBE
HBE
Steel
Plate
• Advantages of SPSW:
• High plastic energy dissipation
• Enhanced stiffness, strength and ductility
• Cost efficient
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Problem Statement
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.
• 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.
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Building Specifications
Floor
psf
Height
Floor 3:
95
12
Floor 2:
90
12
Floor 1:
92
12
Total length:
150
𝑓𝑡
Total width:
120
𝑓𝑡
Total floor area:
13,740
𝑓𝑡 2
Total weight:
3,806
𝑘𝑖𝑝𝑠
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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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AISC Seismic Code Provisions
• Determine preliminary sizes for the
three main components of the Lateral
System
• SPSW
• HBE
• VBE
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AISC Seismic Code Provisions
• 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°
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AISC Seismic Code Provisions
• 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
13
AISC Seismic Code Provisions
• Final member sizes
• 2nd floor steel plate redesigned
• 3rd and 2nd floor HBE redesigned
• Final design
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SAP2000 Analysis of Structure
Building Drift:
Inelastic building
5.35 in
roof drift
Maximum allowable 10.8 in
building drift
Roof drift over
1.2 %
building height %
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SAP2000 Analysis of Structure
• Figures of forces acting on the structure
Moment
Moment
Axial
forces Shear
Shear
forces
Axial
forces
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?
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