A study on the riprap movement based on marine hydrodynamic model and field observation

The study of mechanisms and the accurate simulation of riprap movement caused by complex hydrodynamics are significant for harbor, channel and coastal engineering. Field measurement of current and riprap drift distance was conducted for a dike project in the port of Lianyungang, Jiangsu Province, China. Meanwhile, a well-validated three-dimensional hydrodynamic model was developed to study and analyze the riprap movement process and the influence of project position combined with the theoretical movement equation of riprap. At the moment of maximum flood, the riprap drift distance is greater than at the moment of maximum ebb. The riprap drift distance increase as the tidal inlet width decreases, which follows a second-order exponential distribution. The riprap mass reduces the riprap drift distance, and the magnitude of the reduction diminishes gradually as the riprap mass increases. Therefore, heavy riprap can reduce the horizontal drift distance in a construction.