鉛直力を受ける鋼管杭の水平挙動に関する非線形解析法 : その2:群杭について

抄録

This paper is the second of two papers dealing with the nonlinear analysis of the lateral behavior of steel pipe piles axially and laterally loaded to failure. In the first, the problem of single piles was examined. In this paper, an analytical method is presented for the nonlinear lateral behavior of pile groups subjected to simultaneous axial and lateral loading, and the analysis is then applied to various examples of square groups of piles in relatively loose sand. The conclusions of this paper may be summarized as follows. 1) The general characteristics of group behavior are similar to those for single pile discribed in previous paper. For example, the vertical force influences the .lateral behavior of pile group, and because of additional moment caused by pile deflection at relatively high vertical load levels, the lateral load-displacement curve has a peak. 2) The group reduction factors based on the lateral resistance at any given displacement are examined. It is found that the group reduction factor tends to increase as the displacement from which the factor is estimated increases, and that the value is maximum at the peak of lateral resistance. 3) The change of moment distribution of individual pile in the groups with increasing lateral displacement and the ultimate state of pile group foundations are discussed.