Model pile skin friction in calcareous sand

A laboratory device is described for measuring the load settlement behaviour of model pile shafts under static and cyclic loading. The results of a series of tests on piles in calcareous sand are then presented, and the effects on static skin friction of such factors as overburden pressure, method of pile installation, relative density and over consolidation ratio are discussed. Comparisons are also made with the results of corresponding tests on piles in a silica sand. Cyclic loading is shown to decrease skin friction, the extent of this decrease depending primarily on the magnitude of cyclic displacement. The effects of cyclic loading are more severe for piles in calcareous sand than for those in silica sand (a).