Please use this identifier to cite or link to this item: https://hdl.handle.net/11681/13540
Title: Waianae small-boat harbor, Oahu, Hawaii, design for wave protection : hydraulic model investigation
Authors: United States. Army. Corps of Engineers. Pacific Ocean Division
Bottin, Robert R.
Chatham, C. E. (Claude E.)
Carver, Robert D.
Keywords: Harbor design
Waianae Small-Boat Harbor
Hawaii
Water waves
Hydraulic models
Small-craft harbors
Harbors
Hydrodynamics
Sediment transport
Sedimentation
Deposition
Publisher: Hydraulics Laboratory (U.S.)
Engineer Research and Development Center (U.S.)
Series/Report no.: Technical report (U.S. Army Engineer Waterways Experiment Station) ; H-76-8.
Description: Technical Report
Abstract: A 1:50- scale (undistorted) hydraulic model, reproducing approximately 1.4 miles of shoreline along the proposed Waianae Small-Boat Harbor site (beginning at Kaneilio Point and extending northwesterly), the surrounding reef, and sufficient offshore area to permit generation of the required test waves, was used to investigate the arrangement and design of proposed harbor configurations with respect to wave action. The basic harbor configuration consisted of (a) an outer breakwater, (b) a stub breakwater , (c) an entrance channel , turning basin, and main access channel, and (d) revetted fill areas in the harbor interior. Variations to the basic configuration involved changes in the alignments and lengths of the breakwater structure, the cross section of the breakwaters used, the size and shape of the turning basin, the location of fill areas, and the location of the launching ramp inside the harbor. A 60-ft-long wave generator and an automated data acquisition and control system (ADACS) were used in model operation. In addition a wave refraction and shoaling analysis was conducted (Appendix A) to transfer wave hindcast data from deep water to the model limits; two-dimensional wave flume tests were conducted (Appendix B) to determine the optimum cross section and structural integrity of the breakwater; and tracer tests were conducted (Appendix C) to qualitatively investigate shoaling patterns in the vicinity of the harbor. It was concluded from test results of the three-dimensional model that : (1.) Existing conditions, plan 1, are characterized by very rough and turbulent waves in the vicinity of the proposed harbor during periods of severe wave attack. (2.) For the improvement plans tested, most wave energy reaching the interior of the harbor was due to diffraction through the entrance rather than from overtopping of, or transmission through, the breakwaters. (3.) Although several of the improvement plans tested resulted in wave heights within the criteria established by POD (a maximum of 2.5 ft in the turning basin and 2.0 ft in the berthing area), plans 5A and 5C were determined to be the optimum improvement plans considering cost and wave protection afforded. (4.) Breaking waves were observed in the entrance channel for some of the more extreme wave conditions, indicating that there will be periods when this channel is not navigable. (5.) The harbor appeared to have no adverse effects on wave-induced currents in the immediate area, and wave-induced circulation should aid in harbor flushing. (6.) There was no tendency for sediment to deposit either inside the harbor or in the harbor entrance; however, for certain wave conditions, sediment tended to deposit in the navigation channel. This may or may not indicate a minor potential problem with shoaling of the entrance channel, but shoaling should be no worse than that presently existing at the proposed harbor site. It was concluded from the two-dimensional stability model that, for the range of wave conditions considered , plans 1 , 2 , and 4 will : (a) Resist significant wave overtopping, (b) prevent excessive wave energy transmission, and (c) maintain their structural integrity. NOTE: This file is large. Allow your browser several minutes to download the file.
Rights: Approved for public release; distribution is unlimited.
URI: http://hdl.handle.net/11681/13540
Appears in Collections:Technical Report

Files in This Item:
File Description SizeFormat 
TR-HL-76-8.pdf16.74 MBAdobe PDFThumbnail
View/Open