Geoscience Reference
In-Depth Information
Computational simulation also has a central role in the project for relating the individ-
ual component and system experiments. Simulation is needed to design and interpret
the individual experimental tests. An important deliverable of the project is improved
computational models for SFSI, calibrated from the experiments, in a form available for
community use.
4. Large-scale testing facilities
4.1. NEES FACILITIES AT CORNELL (http://nees.cornell.edu,
PROF. HARRY E. STEWART, PI)
The Cornell Large-Displacement Facility is a unique, world-class resource for research,
education, and outreach focused on underground lifeline response to large ground defor-
mation and the seismic performance of highly ductile above-ground structures using
advanced materials and construction (material below is extracted from the website
http://nees.cornell.edu).
Figure 5.23a shows a 3-D perspective view of the Cornell facility to scale, showing a
splittestbasinsimilartoonepreviouslyusedforlarge-scaleexperiments.Thesplitbasin
in the figure involves approximately 54 m
3
of soil, thus illustrating the size of test that
can be run using the full capacity of soil stored in the facility soil storage bins (55 m
3
)
.
Large-displacementhydraulicactuatorsareusedtomovethetestbasins.Reactionforthe
actuators is provided by a modular reaction wall, which is heavily post-tensioned and
anchored tobedrock witha systemof rock bolts.
Figure 5.23b shows a new split test basin with a 65
◦
fault crossing. One section of the
basin is fixed to the low section of the modular reaction wall and the other movable.
Buriedinthetestbasinisanominal400-mm-diameter,IPS,HDPEpipe.Thepipesection
is approximately 11 m long and fixed at the test basin ends. There is roughly 1.2 m of
soil cover above the pipe. The movable basin can be displaced 1.2 m along the 65
◦
split,
placingthepipeintensionandseverebending.Thisexperimentengagesover100tonsof
soil.
Figure 5.23c shows an overhead view of the test basing after movement. The deformed
shapeofthepipelineissketchedonthephoto.Inthefigurethezonesofactiveandpassive
soil movement can be seen close to the simulated fault. Figure 5.23d shows an alternate
view of the test basing, showing the zones of soil movement. Experiments in the test
basingalsohavebeencompletedwithanominal152-mm-diametersteelpipeandanom-
inal 254-mm-diameter HDPE pipe section.
Large-scale experiments also were successfully completed to evaluate the effects of
earthquake-inducedgroundruptureonweldedsteelpipelineswithelbows.Figures5.23e
and5.23fshowtwoexperimentalbasinswithatotalof60-65metrictonsofsoilthatwere
displaced1mrelativetoeachothertosimulatethetypeofabruptdisplacementgenerated
by liquefaction-induced lateral spread, landslides, and surface faulting.
