Long piles are ofen used in or near the crest of the slope of the sand mound in the port constructions. The influence of the slope on the lateral resistance of a long pile is investigated by a series of centrifuge model tests.
　In order to avoid obtaining misleading conclusions from the model tests, the authors started with a fairly simple situation of a long pile embedded in a uniform
horizontal layer, in which the validity of centrifuge modelling is confirmed by the modelling of models changing the acceleration from 20g to 75g. Then a series of model tests are carried out changing the slope angle, slope height, flexural rigidity of piles, pile width and position of a pile relative to the crest of the slope. The influence of slope on the lateral resistance of a long pile is determined and presented in a simple diagram.