Centrifuge Modeling of Circular Sallow Foundation Reinforced with a Thin Sleeve

抄録

A reinforcing method for a surface circular foundation with a thin flexible underground structure, called “sleeve”, is proposed in this paper. The sleeve wraps soil cylinder underneath a surface circular foundation to confine lateral movements of the soil cylinder. This constraint increases lateral confining pressure, which improves shear strength and stiffness of the soil cylinder underneath the circular foundation. Consequently, the bearing capacity of the surface circular foundation increases and reaches that of massive conventional embedded foundations. In this paper, a series of loading tests of model footings on model sand was conducted to investigate the effects of reinforcement with a sleeve structure. The circular model foundation was made of aluminium with a diameter of 30 mm. A sleeve structure with dimensions of 40 mm in diameter and 30 mm in height was made from a thin polyethylene terephthalate film with a thickness of 0.1 mm. Comparisons of performances of foundations between embedded foundations and surface foundation with sleeve were made and the advantages of surface foundation with sleeve are discussed. The results showed that the surface foundation of 1.5 m in diameter with sleeve provided similar values of bearing capacity obtained from a conventional massive foundation embedded at 1.5 m in prototype scale.