Introduction to Shake Table and Its testing and its comparison with other dynamic analysis methods for buildings

2. GROUP MEMBERS
AWAIS ANJUM UW-10-CE-BE-007
IFTIKHAR ZULFIQAR UW-10-CE-BE-009
MOBASHER IQBAL UW-10-CE-BE-016
SYED MUNSIF ALI NAQVI UW-10-CE-BE-017
SHAHZADA DANYAL SULTAN UW-10-CE-BE-045
WALLI AJAZ UW-10-CE-BE-050

3. Shake table Analysis and Modeling

4. INTRODUCTION
One of the most important challenges facing civil engineers is
mitigating the severe human and economic consequences of
structural dynamic responses to various large-scale excitations
like earthquakes, hurricanes, and blasts.
As such, hazard mitigation has been an important addition to
the undergraduate civil engineering curriculum in recent
years. Increasing access to this curriculum through emerging
teleoperation and teleobservation technologies is an
opportunity for innovating traditional civil engineering
education.

6. SHAKE TABLE
The shake table is a device that
simulates a seismic event. It can also be
used to create fictional “worst case”
scenarios or resonant frequencies.
Shake tables are traditionally used for
experimental research in earthquake
engineering and are computer
controlled.

7. NEEDS FOR SHAKE TABLE
TEST
• Study the seismic performance of non structural components
and complex systems.
• Provide data to calibrate analytical models.
• Validate design, construction concepts and details.

8. APPLICATIONS
Shake table is used for studying
Earthquake response,
Design and build model structures, modify their structures.
Measure structural responses, and reproduce several
earthquake records.

9. SPECIMENS TESTED ON SHAKE
TABLE
• Non-Structural Components
e.g. anchors, racks
• Structural Components
e.g. columns, dampers
• Substructures
e.g. frames, joints, walls
• Complete Structures
– e.g. buildings, bridges, wind turbines

10. ADVANTAGES OF SHAKE TABLE TESTS
OVER OTHER TESTING METHODS
• More realistic consideration of dynamic effects
– inertia forces
– damping forces
– no need to attach loading devices that may
influence the structural performance
• Best / more direct way to simulate earthquake ground motion
effects

11. DYNAMIC EFFECTS
• Quasi-static test • Shake-table test

12. CONSTRAINTS OF SHAKE-TABLE
TESTS
• Cost
• Shake table availability
• Equipment capacity
• Accuracy of certain measurements
• Limited time to react if things go wrong

13. TESTING FLOW CHART

14. EXTRACTION OF TEST
SUBSTRUCTURES
• Special considerations to be paid on
– Gravity loading conditions
– Seismic loading conditions

15. SCALING
• Scale models
– should satisfy similitude requirements so that they
can be used to study the response of full scale
structures
• Similitude requirements
– based on dimensional analysis

16. Fundamental Dimensions in
Physical Problems
• Length (L)
• Force (F) or Mass (M)
• Time ( T)
• Temperature (θ)
• Electrical charge

17. EXAMPLE OF
ADEQUATE/DISTORTED MODEL
Small-scale specimen Large-scale specimen

18. INFILL EXAMPLE
• 2/3-scale, three-story,
masonry infilled,non
ductile RC frame
• tested in Fall 2008

19. INSTRUMENTATION
• Instrumentation
– 135 strain-gauges
– 66 accelerometers
– 79displacement
transducers
• Story displacements
– Mass-less poles
– Deformation of triangles
attached on the RC frame.

20. BEHAVIOR OF PHYSICAL
SPECIMEN

21. Failure Patterns

22. PROTOTYPE STRUCTURE
• Represents structures built in California
1920’s
• Earliest building code we found: 1936
• Design considerations
– Currently available materials used
– Only gravity loads considered
– Allowable stress design procedure
– Contribution of infills ignored
– No shear reinforcement in beams

23. CONCLUSION
• Shake table exhibits better results as compared to other
testing methods.
• Scaled building can be tested on Shake table to know the
seismic behaviour of any building .

24. THANKYOU