stereoscopic, photogrammetric instruments in conjunction with the 

 photographs, details of structural geometry can be defined at a point in time. 

 By direct comparison of photographs taken at different times, as well as the 

 photogrammetric data resolved from each set of photographs, geometric 

 changes of the structure can be defined as a ftinction of time. Thus, periodic 

 inspections of the structures will capture permanent data that can be compared 

 and analyzed to determine if structure changes are occurring that indicate 

 possible failure modes and the need to monitor the structure(s) more closely. 



The breakwaters at Kahului Harbor, Maui, Hawaii, and Laupahoehoe, 

 Hawaii, Hawaii, were nominated by the U.S. Army Engineer Division, 

 Pacific Ocean (POD). A brief overview of the history of these unique 

 structures follows. 



Kahului Harbor 



Kahului Harbor is the only deep-draft harbor on the island of Maui. Maui 

 is the second largest of the Hawaiian Islands. The harbor is approximately 

 94 miles' southeast of Honolulu and is centrally located on Maui's north shore 

 (Figure 1). 



The harbor is exposed to winds and waves from the north and northeast. 

 Both northeast tradewind waves and northern swell impact on Kahului Harbor. 

 The trade winds predominate the summer season, producing 6- to 10-sec, 

 4- to 12-ft deepwater waves. Intense winter storms in the north Pacific Ocean 

 create northern swell during the months of October through March. 

 Deepwater waves can attain heights of 25 ft with wave periods from 12 to 

 18 sec. These storms and, more recently, hurricanes are the sources of the 

 largest waves that reach the Hawaiian islands. 



Kahului Harbor is rich in construction, repair, and rehabilitation history as 

 reported by POD (1981) and Sargent, Markle, and Grace (1988). The harbor 

 complex got its start when a berthing area, dredged entrance channel and 

 400-ft-long, armor stone east breakwater were constructed by the Kahului 

 Railroad Company in 1900. The Corps of Engineers' first involvement with 

 the project came in 1913 when the east breakwater was extended 400 ft. The 

 west breakwater was constructed to a length of 1,950 ft in 1919. In 1931, the 

 east and west breakwaters were extended to their current lengths of 2,766 ft 

 and 2315 ft, respectively. All original construction used a single layer of 

 keyed and fitted, 8-ton armor stone placed between the + 13-ft mean low 

 lower water (mllw) crest and -15 ft mllw (Figure 2). Side slopes above 

 -15 ft mllw were IV on 2H on the heads and IV on 1.5H on the trunks. 

 Below -15 ft mllw, the IV on IH sloped structure was constructed of quarry 

 run stone (25 lb minimum stone weight). 



' A table of factors for converting non-SI units of measurement to SI units is presented on 

 page V. 



Chapter 1 Introduction 



