Abstract
In this article, negative skin friction is discussed which acts on a pile-group when consolidation of clay layer is completed. It is shown that the solution of Zeevaert, which treated piles whose end-points do not settle, is not valid when surcharge on the surface of the clay layer is less than a certain value. The solutions of this case are given. Furthermore, the behaviors of negative skin friction acting on piles whose end-point settles are discussed. It it examined by some calculated examples how the surcharge on the surface of the clay layer, the load on the pile-head, distance between the piles, settlement-rigidity of the supporting layer overlain by the clay layer, and compressibility of the clay layer have influence on settlement of the piles and distributions of negative skin friction and axial force. The method of Terzaghi and Peck to calculate the axial force of the pile at the end-point is indicated to give an exact estimate or slight overestimate when the surcharge on the surface is small and to give a considerable overestimate when the surcharge is large.
