| Summary: | 碩士 === 淡江大學 === 水資源及環境工程學系 === 85 === The coast has been shocked by the fatal force of the
nature and the the sedimentation then showed complicate
geomeorphic process. The incident waves on a sandy sloping
beach will change the beach profile due to the
sedimentation. A laboratory tests are performed in order
to study the quantities of dune erosion due to attacks of
different wave conditions.By using the flume experiment, we
examined the dune erosion and the sedimentation on the single
slope. The sediments were transported from the offshore to the
foreshore region in according to the wave showered propagation.
The dune were eroded when waves collide dune. That makes the
dune back. As waves backwash, some eroded sand was carried
offshore and some were stored in front of the dune. The
topography was changed by the action of these waves. In the
beginning,thesandy slopping beach topography was
changedintensively beacause of the waves attack. As the test
duration is elapsed, the equilibrium beach may has been
reached. We will find the quantities of the sedimentation and
the eroded dune for different wave heights, dune locations
and wave periods. The waves height and the dune location are
the most important. The waves height and the dune location are
the most important. The wave period has less important
influence on the rate of dune erosion. The effects of
different dune locations on a sloping besch are also
investigated. The comparison and discussion between the
former results of Chern''s(1995)numerical scheme and Tsou''
s(1994)laboratory tests are studied and discussed by a
geographic graph. The relation between wave steepness and the
steepness of sand bar has also been also discussed.
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