The Influence of Geometry of Pedestal Piles in Silt on Uplift Behavior

Abstract

The uplift behavior of rigid pedestal pile is affected by the geometry, which is not totally same with plate anchor. A series of uplift tests of relatively large scale pile models with various dimensions in silt soil have been conducted to investigate the influence of angles of enlarged base, ratio of base and shaft diameters and embedment ratios. The whole trend is that uplift capacity will decrease with the increase of angle of enlarged base. The maximum difference of ultimate uplift load for various angles of enlarged base is within 20%. Soil surrounding pile base can be mobilized when ratio of base and shaft diameters is no less than 2.0, otherwise the part of enlarged base will not take effect fully. A gently curved rupture surface emerged from the edge of enlarged base to soil surface when embedment ratio is no more than 3. For deep rigid pedestal pile, a balloon-shaped rupture surface occurred. The height of whole rupture is 2.7D.