一维数学模型在堤前滩面短期演变计算中的应用

Application of one-line mathematical model in calculating short-term evolution of shore beach of a levee

采用波浪上涌区的输沙率计算公式和波浪浅化区及破波带内的泥沙输沙率计算公式,建立波浪作用下海滩横向冲淤演变的一维数学模型,用以模拟风浪引起的床沙短期运动及滩面的冲淤空间变化。将该模型应用于杭州湾某海防工程堤前滩面的冲淤演变计算,模拟了某次台风期间堤前滩面的冲淤变化,并与实测资料进行比较。模拟结果表明该模型对于台风期间堤前滩面的冲淤变化可以给出合理的模拟结果,冲淤部位及冲淤量均达到一定的工程精度要求,且该数学模型数值求解简单易行,计算效率较高。

A one-line mathematical model for the evolution of cross-shore beach under waves was established to simulate the short-term motion of bed sand and the spatial variation of beach induced by waves by use of equations of sediment transport separately for swash zones and shallow-water zones of waves.This model was applied in the calculation of evolution of shore beach of a levee in Hangzhou Bay.The beach evolution during a storm was numerically simulated,and the predicted results were compared with the observed data.The results show that the proposed model can provide rational predictions for the beach evolution during the storm,and the deposition position and amount both reach certain requirements for project accuracy.It is simple,applicable and has high computational efficiency.