Wave run-up was found to increase when the breakwater slope was steepened. It was found that the height to which waves will advance up the slope of breakwaters of the type tested is a function primarily of the breakwater slope and the steepness of the waves. In conjunction with the stability tests, wave run-up data were obtained for each rubble-mound test section and wave condition. For the quarry-stone-type armor unit, and for the no-damage and no-overtopping criteria, the experimental coefficient is constant. The test data obtained to date indicate that the experimental coefficient varies primarily with the shape of armor unit and the amount of damage to the cover layer. The new formula is dimensionally homogeneous and contains only one experimental coefficient. Using the experimental data to determine the unknown functions in the derived equation, a new formula was obtained for the weight of armor units required to insure their stability when used as the cover layer of rubble-mound breakwaters. Test results indicate that the assumptions upon which analysis of the phenomenon was based are essentially correct. A general stability equation was first derived, based on a rational analysis of the forces exerted on armor units when waves impinge on rubble-mound breakwaters, and used to guide the experimental program and correlate the test data. Tests have also been conducted in which damage to the quarry-stone-type cover layer was determined as a function of wave height in these tests waves with heights greater than those corresponding to incipient instability were used. To date pertinent relations between these variables have been determined for the condition of incipient instability, using armor units simulating quarry stones of irregular shape with rounded edges and a fairly smooth surface. The limit of stability of the armor units forming the protective cover layer is determined as a function of the wave dimensions, slope of exposed breakwater face, weight and specific weight of the armor units, and specific weight of the water in which the test sections are situated. For the laboratory tests, small-scale rubble-mound breakwater sections are hand-constructed in a concrete flume 119 ft long, 5 ft wide, and 4 ft deep, and subjected to mechanically generated waves. Summary: The need for fundamental data for use in designing rubble-mound breakwaters led to a laboratory investigation to develop design criteria the first phase of this investigation, which dealt with the design of quarry-stone cover layers, is described in this report. Army Engineer Waterways Experiment Station) no. Army Engineer Waterways Experiment Station.Įngineer Research and Development Center (U.S.) Please use this identifier to cite or link to this item:ĭesign of quarry-stone cover layers for rubble-mound breakwaters : hydraulic laboratory investigation
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |