Title page for ETD etd-040799-050250


Type of Document Master's Thesis
Author Archilla, Juan Carlos
URN etd-040799-050250
Title Three-Dimensional Nonlinear Dynamics of a Moored Cylinder to be Used as a Breakwater
Degree Master of Science
Department Civil Engineering
Advisory Committee
Advisor Name Title
Plaut, Raymond H. Committee Chair
Barker, Richard M. Committee Member
Holzer, Siegfried M. Committee Member
Keywords
  • mooring
  • breakwater
  • vibration
  • cylinder
  • snap load
  • nonlinear dynamics
  • chaos
Date of Defense 1999-04-05
Availability unrestricted
Abstract
A three-dimensional, nonlinear dynamic analysis

is conducted on a fully submerged, rigid, solid

cylinder to be used as a breakwater. The breakwater

could potentially be used as a single cylinder to

protect small structures. Alternatively, multiple

cylinders could be positioned in series to protect

shorelines, harbors, or moored vessels from

destructive incident water waves. The cylinder is

positioned with its axis horizontal and is moored to

the seafloor with four symmetrically placed massless

mooring lines connected at the ends of the cylinder.

The mooring lines are modeled as both linearly elastic

("regular") springs and compressionless springs.

All six degrees of freedom of the structure are

considered. The breakwater is modeled in air with a

net buoyant force acting through the cylinder's center

of gravity. The six "dry" natural frequencies of the

structure are computed. Both linear and nonlinear free

vibrations of the structure are considered. Linear

damping is used to model the fluid and mooring damping

effects. Normal and oblique harmonic wave forces at

various frequencies and amplitudes are applied to the

cylinder. The effects of the forcing amplitude and

frequency, and the coefficient of damping, on the motion

of the breakwater are studied. The results show that

more erratic behavior occurs for the breakwater with

compressionless springs, mainly due to the development

of snap loads in the mooring lines.

Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  Back.pdf 63.02 Kb 00:00:17 00:00:09 00:00:07 00:00:03 < 00:00:01
  chapter1.pdf 25.39 Kb 00:00:07 00:00:03 00:00:03 00:00:01 < 00:00:01
  chapter2.pdf 123.12 Kb 00:00:34 00:00:17 00:00:15 00:00:07 < 00:00:01
  chapter3.pdf 3.65 Mb 00:16:54 00:08:41 00:07:36 00:03:48 00:00:19
  chapter4.pdf 6.49 Mb 00:30:03 00:15:27 00:13:31 00:06:45 00:00:34
  chapter5.pdf 13.42 Mb 01:02:08 00:31:57 00:27:58 00:13:59 00:01:11
  chapter6.pdf 10.94 Kb 00:00:03 00:00:01 00:00:01 < 00:00:01 < 00:00:01
  Front.pdf 80.00 Kb 00:00:22 00:00:11 00:00:09 00:00:04 < 00:00:01

Browse All Available ETDs by ( Author | Department )

dla home
etds imagebase journals news ereserve special collections
virgnia tech home contact dla university libraries

If you have questions or technical problems, please Contact DLA.