Study On The Wash-out And Cave-in Method Of Roadbed Slopes By Wave In Three Gorges Reservoir

The construction of There Gorges Project, will make the water level of reservoir region rise to a great extent, and the water surface will be much wider. The distance that winds blow on the water surface will increase rapidly, then the wind waves with greater wave height will be formed. And large-size ship will sail in the reservoir. So, after the project finished, the wave must do more harm to the roadbed slope along the reservoir bank.In this thesis, based on the author's survey on the spot, the roadbed slop breakage owing to waves are divided to two kinds: 1) the wash-out of the particle slope ; 2) the cave-in of the clay slope.The wash-out of the particle slope, in practice is how the particle stone to move under the breaking wave's force. The main elements deciding the force are the wave factor (wave height), the slope angle and the particle size. Through analyzing the particle's suffering process during each stage of wave's breaking, it can be advanced that the wave force is biggest just at the wave incidence to the slope. In laboratory, the author proceeds experiments for the combinations of different wave heights and slope angles to the monolithic slope(slab-slope), and experiments for the combinations of different wave heights, slope angles and particle sizes to the particle slope, acquiring a large quantity of wave pressure data. Based on the current Soviets formula only used for the calculation of the vertical wave pressure on monolithic slope, handling these wave pressure data by the method of single factor returning analysis step by step in the criterion of acquiring higher relation coefficients, the author not only revises the current vertical wave pressure formula, but also wins the formula used to calculate the particle slope's vertical wave pressure and the monolithic or particle slopes' upward(along the surface of slope), downward (along the surface of slope) or level(paralleling the slope-bank) wave pressures. These formula resolve the problem how to calculate the forces that breaking wave acts on the particle slope.The damage degree that waves scour the clay roadbed slopes, is mainly determined by the wave factor(wave height), the clay slope angle and the clay compactness. To the clay slope, proceeding long-time washing experiments for the combinations of two slope angles, several wave heights and clay compactness, the author advances that the breakage which waves act on the clay roadbed slopes is a repeating cave-in, and will be more serious with the increase of wave height or slope angle or the decrease of clay compactness.