Abstract
A new theory on the design of the cotter-pile (Kusabi-gui), which functions as a cotter inserted through two layers, is proposed in this paper. Its feature is to use the pile design theory and the assessment theory on the stability of slope simultaneously. The mechanical equilibrium of interslice-forces of the landslide mass and that of the moments of the whole system are considered in it. It reduces the arbitrariness of the figures which a designer adopts in design calculation and offers the better results with theoretical compatibility compared to th former one.
