The evolvement history of modern Huanghe River Delta tidal flat, coastline and underwater terrain were studied based on the analysis of remote sensing images and water depth data. Based on the analysis of seafloor ter...The evolvement history of modern Huanghe River Delta tidal flat, coastline and underwater terrain were studied based on the analysis of remote sensing images and water depth data. Based on the analysis of seafloor terrain evolution on different historical stages, a formula simulating the erosion and deposition evolvement model of subaqueous Huanghe River Delta slope was proposed, and the evolvement trend of the subaqueous delta terrain was predicted. The result shows that the equilibrium transition zone is near the water depth of 12 m with seabed erosion in shallower water and accumulation in deeper water during the first 150 a after the river channel was deserted. In the meantime, the underwater slope became gentler and the coastal erosion rate became slow gradually. Then, the subaqueous delta slope changed to up concave from upper convex, and the shape of subaqueous delta disappeared. The coast type changed to silt-mud coast about 100-150 a after the river course was deserted. The erosion depth in the foot of the seawall is calculated based on the formula.展开更多
In the year of 2011, in the emergency reinforcement project of the main dike of Yangtze River in Luhe District, Nanjing City, four underground pipelines were vertically crossed with the embankment. In this project, ea...In the year of 2011, in the emergency reinforcement project of the main dike of Yangtze River in Luhe District, Nanjing City, four underground pipelines were vertically crossed with the embankment. In this project, each pipeline had been es- tablished independent culvert structure for protection and high pressure injection method had been used for the foundation treatment. To extend the length of the foot of slope and to improve the impermeable capacity of the dike, additional com- posite geomembranes had been installed in the riverside slope. By optimizing the construction program and enhancing the settlement observation during the constrution period, the safe operation of the pipelines had therefore been ensured.展开更多
基金The National Basic Research Program of China under contract No. 2005CB422304
文摘The evolvement history of modern Huanghe River Delta tidal flat, coastline and underwater terrain were studied based on the analysis of remote sensing images and water depth data. Based on the analysis of seafloor terrain evolution on different historical stages, a formula simulating the erosion and deposition evolvement model of subaqueous Huanghe River Delta slope was proposed, and the evolvement trend of the subaqueous delta terrain was predicted. The result shows that the equilibrium transition zone is near the water depth of 12 m with seabed erosion in shallower water and accumulation in deeper water during the first 150 a after the river channel was deserted. In the meantime, the underwater slope became gentler and the coastal erosion rate became slow gradually. Then, the subaqueous delta slope changed to up concave from upper convex, and the shape of subaqueous delta disappeared. The coast type changed to silt-mud coast about 100-150 a after the river course was deserted. The erosion depth in the foot of the seawall is calculated based on the formula.
文摘In the year of 2011, in the emergency reinforcement project of the main dike of Yangtze River in Luhe District, Nanjing City, four underground pipelines were vertically crossed with the embankment. In this project, each pipeline had been es- tablished independent culvert structure for protection and high pressure injection method had been used for the foundation treatment. To extend the length of the foot of slope and to improve the impermeable capacity of the dike, additional com- posite geomembranes had been installed in the riverside slope. By optimizing the construction program and enhancing the settlement observation during the constrution period, the safe operation of the pipelines had therefore been ensured.