Study of Beach Widening by the Perched Beach Concept Santa Monica Bay,California. Hydraulic Model Investigation.

摘要

Hydraulic model studies were conducted at the U.S. Army Engineer Waterways Experiment Station to aid in determining the technical feasibility and optimum design factors of the perched beach concept for widening the existing beach to provide right-of-way for a freeway along a portion of the Santa Monica Bay coastline. Only the following three parts of the study were completed: (a) An undistorted,three-dimension,fixed-bed model (scale 1:100was used to determine the effect of the perched beach on rip currents. If adverse interactions were found to be present,the model was to be used to determine means of minimizing them. (b) A distorted-scale (1:100horizontal, 1:50vertical),two-dimensional, movalble-bed model was used to estimate the amount of sand which might be lost seaward over the toe structure due to normal and storm wave actions and to determine the optimum crown elevation of the submerged structure and the length of stone riprap paron required to reduce the seaward migration of sand to a minimum. (c) An undistorted,two-dimensional model (scale 1:30) was used to determine the structural design of the proposed rubble-mound toe structure for various depths. (Modified author abstract)