Location and Symbol
Force Horizontal, FH
Horizontal actuator load measurement
Deflection Horizontal, DH
Horizontal deflection, shear panel deformation
Force Vertical South, FVS
Manual vertical load control (25k total load w/#5)
Deflection Vertical South, DVS
Stroke (tied to #6)
Force Vertical North, FVN
Load (summed with #3, for 25k total load)
Deflection Vertical North, DVN
Controlled by #4 stroke feedback
Defl Horiz Bot Track, DHBT
To ensure no slippage
Defl Vert South Bot Track, DVSBT
To ensure no uplift
Defl Vert North Bot Track, DVNBT
To ensure no uplift
10 LRDG* (20")
Defl Horiz Top Track, DHTT
Check for shear panel deformation - same as #2
Defl Vert South Top Track, DVSTT Vertical panel/column deformation & rotation check
Defl Vert North Top Track, DVNTT Vertical panel/column deformation & rotation check
Note: * Linear Resistance Deflection Gauge, often called a Yo-Yo Gauge.
F6. TEST REQUIREMENTS. For each shear panel qualified, three specimens shall be fabricated
and tested. This assumes only minor variation in panel performance for a given shear panel. If large
variations occur more than three specimens shall be tested and a statistical evaluation of panel
performance may be required. For panels with minor variation, one specimen shall be tested
monotonically and two shall be tested cyclically as defined below. All tests, both monotonic and
cyclic shall use stroke control, loading the panels laterally at a constant displacement per minute.
The vertical load shall be held constant and the top beam shall be held horizontal throughout each
test as described in Paragraph F4, Test Configuration. Both monotonic and cyclic tests shall be
conducted up to deflections that cause ultimate failure of the shear panels, or reach the limits of the
test equipment, but shall not be less than 10 times the lateral yield displacement of the test panel, y.
These are very large deflections, well beyond acceptable drift limits, but are needed to ensure that
brittle failures (sudden loss of lateral or vertical load carrying capacity) do not occur near the useful
deflection range of the panel.
a. Monotonic Test Protocol. A single specimen of each shear panel shall be loaded in one
direction (monotonic) at a constant stroke rate that is slow enough to allow careful observation of
panel performance and failure progression . These observations shall include documentation of
panel behavior through a log of observations with respect to displacement and photographs. Load
versus deflection (TSF versus DH) shall be plotted to determine the measured lateral yield
displacement y. This value shall be used in defining the cyclic test protocol.
b. Cyclic Test Protocol. A minimum of two specimens of each panel configuration shall be
loaded cyclically at a constant stroke rate that is slow enough to allow careful observation of panel
performance and failure progression . These observations shall include documentation of panel
behavior through a log of observations with respect to displacement and photographs. Load versus
deflection (TSF versus DH) shall be plotted to create load/deflection hysteretic envelopes. The cyclic
load protocol follows a standard method, so that test results may be compared with cyclic test results
of other systems. The protocol defined here is similar to SAC2 guidelines that have been modified to
scale to the lateral yield deflection as described in ATC-24 . The SAC recommended loading
histories call for loading with a deformation parameter based on interstory drift angle, defined as
Monotonic tests conducted at USACERL used a stroke rate of 0.5 inches per minute.
Cyclic tests conducted at USACERL used a stroke rate of 3 and 6 inches per minute. The faster stroke rate was used for
panels tested cyclically beyond 10 inches (20 inches peak to peak).
SAC Testing Programs and Loading Histories, unpublished guidance, 1997.
Applied Technical Council (ATC) 24, Guidelines for Cyclic Seismic Testing of Components of Steel Structures, 1992.