Large-scale experiments have been conducted in a wave tank with a
104 m-long, 3.7 m-wide, and 4.6 m-deep wave channel with a plane
slope (1:2) located at one end of the tank; part of the experimental
setup is shown in Fig. 1. A solid wedge was used
to model the landslide. The triangular face had a horizontal length
of = 91 cm, a vertical face with a height of = 45.5 cm, and
a width of = 61 cm (Fig. 2). The horizontal
surface of the wedge was initially positioned either a small
distance above or below the still water level to reproduce a
subaerial or submarine landslide. The block was released from rest,
abruptly moving downslope under gravity, rolling on specially
designed wheels (with low friction bearings) riding on aluminum
strips with shallow grooves inset into the slope. The wedge was
instrumented with an accelerometer to accurately define the
acceleration-time history and a position indicator to independently
determine the velocity and position time histories. Wedge positions
are given in Fig. 3 for the two cases presented
here.
Figure 1: Picture of part of the experimental
setup.
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A sufficient number of wave gages were used to determine the seaward
propagating waves, the waves propagating to either side of the
wedge, and for the submerged case, the water surface-time history
over the wedge. In addition, the time history of the runup on the
slope was accurately measured. Time histories of the surface
elevations and runup measurements for two cases are presented in
Figs. 4 and 5 for the submerged
cases with
m and m, respectively.
While a total of more than 50 experiments with moving wedges,
hemispheres, and rectangles were conducted (Liu et al.,
2005), the wedge experiments were used as benchmark tests in the
2004 Catalina Island, Los Angeles, California workshop (Liu et al., 2008). Details and more experimental results can be
found in Liu et al. (2005).
Figure 2: Schematic of the experimental
setup. Gage locations where time
histories of the surface elevation and runup measurements are
provided: gage 1 at
, gage 2 at
, runup gage 2 at
, and runup
gage 3 at
. While -axes follows center cross
section pointing seaward -axes follows the initial shoreline
starting from center cross section.
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Figure 4: Time histories of the surface elevation
(gage 1 and gage 2) and runup
(runup gage 2 and runup gage 3)
measurements with respect to still water level for the submerged
case with
m.
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Figure 5: Time histories of the surface elevation
(gage 1 and gage 2) and runup
(runup gage 2 and runup gage 3)
measurements with respect to still water level for the submerged
case with m.
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References:
Liu, P.L.-F., T.-R. Wu, F. Raichlen, C.E. Synolakis, and J. Borrero
(2005): Runup and rundown generated by
three-dimensional sliding
masses. J. Fluid Mech., 536, 107-144.
Liu, P.L.-F., H. Yeh, and C. Synolakis (2008): Advanced Numerical
Models for Simulating Tsunami Waves and Runup. Advances in
Coastal and Ocean Engineering, 10, 250 pp.
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