Erosion problems are not only in the Texas area, but exist also along the coastline
all over the world. Even though many researchers have studied coastal processes
related with beach erosion and deposition over the decades, these processes are too
complex to understand completely and field measurements are difficult to obtain
during landfall of storms which cause fatal damages.
Overwash is strongly suspected to cause extreme erosion as seen from long-term
field measurements in the upper Texas coast. Overwash and washover are the source of
cross-shore erosion and deposition of beach material along the coast, respectively.
Waves superimposed on increased storm surges overtop and generate serious erosion of
the berm. However, the data for these processes do not completely describe the
shoreline erosion problems. Providing better descriptions requires field measurements
and laboratory experiments with careful calibration.
This study was conducted in two major sections. First was a field measurement
and second was a laboratory experiment.
This study used the RTK-DGPS to measure the change in the beach profile over
multi year period. The GPS system is one of the ways to have the best resolution. The laboratory experiment was done in a 2D wave tank on mid-scale based on
similitude law at Texas A&M University. The experiment was necessary to obtain
better empirical formulas.
The erosion rate of the sand was measured at different wave conditions and slopes
of the berm or upper beach face in regular and irregular waves respectively. The
erosion rate is much bigger at higher wave height, longer wave period and steeper
beach face. The erosion rate is increased proportional to speed of bore and it is
decreased with time.
The empirical formulas were the first approach to simulate the impact of overwash.
The laboratory results represented good agreement with the field data and might be
applicable to predict the shoreline recession by overwash induced by storms. Further
improvements can be expected by adding these empirical formulas to a numerical
model to predict sediment transport in the swash zone.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/ETD-TAMU-1171 |
| Date | 15 May 2009 |
| Creators | Park, Young Hyun |
| Contributors | Edge, Billy L. |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Dissertation, text |
| Format | electronic, application/pdf, born digital |
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