1. Department of Civil Structural and Environmental Engineering
Experimental Seismic Fragility of Steel Studded Gypsum Partition Walls and Fire Sprinkler Piping Subsystems
Andre Filiatrault, Gilberto Mosqueda, Rodrigo Retamales, Ryan Davies, YuanTian, and Jessica Fuchs
Department of Civil Structural and Environmental Engineering
University at Buffalo
NSF Award CMMI
NEESR-GC: Simulation of the Seismic Performance of Nonstructural Systems
PI Manos Maragakis, University at Nevada, Reno
Quake Summit 2010
NEES& PEER Annual Meeting
San Francisco, Oct 8-9, 2010

2. Contents
Objectives of NEESR Nonstructural GC subsystem testing program at University at Buffalo
Experimental seismic fragility of steel-studded gypsum partition walls
Experimental seismic fragility of sprinkler piping systems

3. Objectives of NEESR Nonstructural GC Subsystem Experiments
Carry out an extensive experimental program to evaluate the seismic response, failure mechanisms, and fragilities of
steel-stud gypsum partition walls
sprinkler piping
ceiling systems
Develop protective technologies and design details to enhance seismic performance of nonstructural systems 3

4. Experimental seismic fragility of steel-studded gypsum partitions walls
Specimen details and parameters selected with advice from practice committee
Material
Connection details
Geometry
Static/dynamic testing
Fifty specimens tested (22 configurations) 4

5. Partition Wall Configurations
Typical 12 foot wall with returns and corner details
2’-4’

6. Partition Wall Configurations
Typical framing and sheathing connectivity details
Basic Connection (slip track)
Full Connection

7. UB-NCS Testing Protocols and Instrumentation
Quasi-static protocol and instrumentation for in-plane testing
Detailed damage inspection
Maximum drift imposed: DMax=3.0%
Minimum drift imposed: DMin=0.15%

8. Partition Wall Configurations
List of specimens and configurations tested

9. Partitions Subsystem In-Plane Experiments
Specimens 1, 2 & 3 (Basic), & Specimen 4 (Gypsum connected to top track)
Top “slip track” acted as intended:
Limited damage to in-plane wall
Damage concentrated in return walls top tracks
Spec 4 performed similarly to specs 1 to 3 after failure of connection of gypsum to top track
Crushing of gypsum in wall corners

10. Partitions Subsystem In-Plane Experiments
Specimens 20, 21 & 22 (Institutional/slip track)
Failure of bottom and top tracks of transverse walls
Severe damage of sheathing in transverse walls
Severe damage of studs at wall intersection
Damage along vertical edges of longitudinal walls

11. Partitions Subsystem In-Plane Experiments
Specimens 23, 24 & 26 (Institutional/Full
Crushing of gypsum around screws connecting to top track and plastic hinge forming on studs due to bending (Specimen 23)
Bottom tracks slip after fasteners passing thru tracks and damage along joints between gypsum boards (Specimen 24)
Tears in all bottom track connections and global wall slip (Specimen 26)
Specimen 23
Specimen 24
Specimen 24
Specimen 26

12. Partitions Subsystem Out-of-Plane Experiments
Specimens 40, 41 & 43, and 39, 45 & 47 (Bookshelf/Walls without and with Returns)
Screws pulled out from gypsum to stud connections & damage in bookshelf connectors
Damage along horizontal joints between gypsum wallboards and along cornerbeads
Collapse of Specimens 40, 43b & 47 (All of them, re-used walls)

13. Partition Wall Subsystems Out-of-Plane Experiments
Specimens 48, 49 & 50 (Partial Height Braced Walls with Returns)
Screws pulled out from connection of braces to top track
Buckling of steel braces
Buckling of top track around brace connections

14. Fragility Assessment Partition Wall Subsystem
Definition of Damage States

15. Fragility Assessment Partition Wall Subsystem
Fragility Data for Group 0: All Specimens Tested In-plane
(All Specimens)
Peirce’s criterion verified
Experimental fragility curves obtained following criteria in document “Developing Fragility Functions for Building Components for ATC-58” by K. Porter, R. Kennedy and B. Bachman (Method A)
j=1, 2 and 3
Lilliefors’ goodness-of-fit test (5% significance level) analyzed

16. Commercial Const. Slip Track
Partial Height
Commercial Const. Slip Track
Damage in tape (DS1) happening at the same time of brace buckling (DS2)
Longitudinal wall induce failure of transverse wall track fasteners
Commercial Const. Full Connection
Commercial Const. All Specimens
Institutional Const. Slip Track
Improved Corner Details
Institutional Const. Full Connection
Institutional Const. All Specimens
No damage observed for DS2 and DS3

17. Experimental seismic fragility of sprinkler piping components
Specimen details and parameters selected with advice from practice committee
Material
Connection type
Pipe diameter
48 T-joint specimens tested under cycle loading
Dynamic subassembly test currently under construction 17

18. Test Setup Typical test specimen layout and instrumentation
The ends of pipes are sealed with caps and slid into couplers welded to the support.
Couplers allow small rotations to simulate pin connections at the end of the pipes.
All pipes are filled with water under city pressure (40 psi measured pressure) to detect leakage.

19. Testing Protocols Testing protocols for monotonic tests
Constant velocity: in/sec
Quasi-static protocols for cyclic tests

20. Test Matrix 20 Pipe / Fitting Material Pipe / Fitting Size (inches)
Number of Monotonic Tests
Number of Cyclic Tests
Testing Status
Black Iron (Threaded) 6 1 3
Completed 4 2
Completed 
3/4
CPVC (Cement Joint)
Steel (Groove Fit Connection Schedule 40)
Steel (Groove Fit Connection Schedule 10)
Total Test: 48 20

21. Piping Tests Phase 1
Identify moment and rotation at joints at which damage state occur
The 1st damage state --- first leakage
The 2nd damage state --- complete fracture at tee joint 21

22. Test Results Specimen BIT 2-1 (Monotonic test)
Force-displacement relation at the tee joint (right)
Moment-rotation relation at the left end of the tee joint--Potentiometer 3 and 4 (bottom left)
Moment-rotation relation at the right end of the tee joint--Potentiometer 5 and 6 (bottom right)
* The vertical red lines on these plots indicate the occurrence of the first leakage

23. Test Results Specimen BIT 2-3 (Cyclic test)
Force-displacement relation at the tee joint (right)
Moment-rotation relation at the left end of the tee joint--Potentiometer 3 and 4 (bottom left)
Moment-rotation relation at the right end of the tee joint--Potentiometer 5 and 6 (bottom right)
Peak value on cycle used for rotation fragility calculation Peak value on cycle used for moment fragility calculation Indicates instantaneous occurrence of first leak
* The red cycles on these plots indicate the cycle during which occurrence of the first leakage happened

24. Summary of Damage Observations
Pipe threads erode due to slippage and Teflon tape degrades
Pipe threads fracture at the edge of tee joint
Glue slips and pipe pulls out from tee joint
Pipe peels off the inner surface of tee joint
Pipe fractures at the edge of tee joint
Damage on the groove of pipe
Damage on the groove of tee joint
Coupling ruptures 24

25. Piping Test Result Summary for Phase 1
Summary of fragility curves
-- Same color indicates pipes of same size;
-- Same line style indicates pipes of same material. 25

26. Dynamic Test Proposal of Sprinkler Piping System
Riser (4 in)
Main line (4 in)
Branch line (2 in & 1 in)
Component
Quantity
Sprinkler head 11
Transverse sway brace 3
Wire restraint 2
Ceiling box 6
Vertical hanger 8

27. Dynamic Test Proposal of Sprinkler Piping System
Long Branch Line Test
Main Line and Riser Test
 Legend
Note
4-way seismic brace
Sprinkle pipe 
Sprinkler head
 Vertical hanger
 Lateral bracing
 Wire restraint
Mass block

28. Test matrix MAINLINE & RISER MATERIAL BRANCH LINE MATERIAL
NUMBER OF TEST
Schedule 10 Steel Groove Fit Connection
Schedule 40 Black Iron Threaded 1
CPVC (cement joint)
Schedule 40 (Dynaflo)
Schedule 40 Steel Groove Fit Connection
Total: 4

29. QUESTIONS/DISCUSSIONS