A FREE HEAD SHORT PILE PENETRATING STIFF CLAY SUBJECTED TO BENDING MOMENT OF A CYCLIC TYPE—NONLINEAR SENSITIVITY INVESTIGATIONS

摘要

This paper presents the sensitivity analysis of a laterally loaded pile-soil interaction system which is subjected to a bending moment of discrete variability. The loading is considered to be of a cyclic type. The pile is embedded in stiff clay, which is modeled by means of a p-y relationship. The pile structure is simulated as a one dimensional beam element. The cyclicity is introduced implicitly to the external loading, whereas the soil response is explicitly dependent on the number of load cycles N. The sensitivity of the pile-soil system is analyzed by means of the adjoint system method, which takes into account the nonlinear features of the system. The p-y parameters of the physical relationship for stiff clay subjected to cyclic loading and the pile's bending stiffness are taken as the design variables. The changes of maximum generalized deflection located at the pile head due to the changes of the design variables are explored by means of the sensitivity integrands associated with each of the design variables. They are considered to be the spatial functions. The numerical investigations are conducted for short piles. They are subjected to bending moments of discrete variability. The numerical results in terms of spatial distributions of sensitivity integrands are presented and discussed in detail.