Full scale study of combined wave and surge overtopping of a levee with RCC strengthening system

Abstract

Most earthen levee damages have occurred on the levee crest and landward-side slope after Hurricane Katrina as a result of either wave overtopping, storm surge overflow, or a combination of both. The goal of this study was to investigate the performance and develop design guidelines for crest and landward-side strengthening system—Roller compaction concrete (RCC). A full-scale experimental study on combined wave and surge overtopping of a levee armored with RCC was conducted in a two-dimensional laboratory wave/flow flume. Erosion of RCC surface was checked after each test. It was found most of the erosion occurred after the first test and, the erosion was related to initial quality of RCC surface. Flow parameters including time series of flow thickness and velocity at 5 locations on the levee crest and landward-side slope were measured. New equations were developed to estimate distribution of instantaneous discharge, distribution of individual wave volumes as well as flow parameters on landward-side slope, including mean flow thickness, RMS wave height, mean velocity, and wave front velocity for the RCC strengthened levee.