SEISMIC ANALYSIS OF A
CONCRETE BUILDING
California State University at Los Angeles
Belen Valencia
Art Chianello
Marlon Calderon
Faculty Advisor: Rupa Purasinghe
Industrial Mentors: Fil Apanay and Roger Li
Analysis
On Campus Concrete Shear Wall Building
Time History Dynamic Analysis
Nonlinear Static Push Over Analysis
Maximum Displacements (in)
San Fernando Earthquake @ Pacoima Dam
(PGA=1.17g, T1=0.1202, T2=0.0692, T3=0.0668)
Push-Over Analysis of Reinforced
Concrete Shear Wall
•
Push-over analysis can provide a significant
insight into the weak links in seismic
performance of a structure or component.
•
RAM Perform 2D was the software used for
this Performance Analysis.
Model of 3 story reinforced concrete shear wall using RAM Perform 2D. The wall is 36 feet high x 200 feet long x
8 inches thick with door openings.
Method of Analysis
• Inelastic material and Diagonal
compression material properties were
defined.
• Any limit states that were exceeded point
to areas in the structure that can be
retrofitted to seismically upgrade the
structure.
Results
Push-over (capacity) curve of reinforced concrete shear wall under uniform pushover loading. Limit States are shown on curve as red lines. First limit state reached
was diagonal tension and shear of concrete, then roof drift. Base shear was 4877
kips at diagonal tension failure.
Capacity
Demand
Results
Deflected shape of wall subject to triangular push-over load. Elements shown in red is
first area of diagonal tension failure.
OBSERVATIONS
• Diagonal Tension/Shear failure is the
controlling factor
– (as it is a long wall)
•
RAM Perform 2D identified the locations
within the wall that fail first.
Modeling as a Beam Column
• A Cross Wall - 25 ft x 36 ft x 8 in
• It was modeled using:
• Load vs. Moment Curve (P-M curve)
• Ram Perform-2D Obtained the capacity
spectrum push-over plot
– Base Shear vs. Drift plot
– Input an earthquake and analyzed how
the structure would react with the induced
EQ load.
Ram Perform
Base Shear (K) vs. Drift
Demand
Capacity
Summary
• We have shown
- conventional TIME HISTORY ANALYSIS
- Non Linear Static Push Over Analysis for better
understanding of the structure
THANKS to
• MCEER
• CSLA ECST Computer Center (Jeff Cheam and Staff)