Discussion on Unsteady Seepage Flow Method in Designing Dykes

The steady seepage flow is usually hypothesized in designing dykes.Based on this hypothesis,the form of dykes is decided by analyzing seepage flowing and slide stability.But if the freshet ebbs and flows too quickly,the time of freshet is so short that the seepage flowing is unsteady.If we design the dyke with this hypothesis,the scale will be too large,and it will be too expensive.The method of unsteady seepage flow used in designing the dyke with this kind of river is studied and discussed.