Ole Hededal

Friction Effects on Lateral Loading Behavior of Rigid Piles

The adequacy of the p-y curves used in the current practice for the design of rigid pile foundations with large diameter, like in the case of monopile foundations of offshore wind turbines, has been widely questioned. The current study aims at analyzing the lateral behavior of rigid piles, while taking into account the shear frictional resistance along the pile. For this purpose efficient three dimensional finite element models of different diameter have been developed. The increase of the side friction and of the diameter of the pile is shown to alter the failure pattern and increase the lateral capacity of the pile. The obtained p-y curves demonstrate the importance of the aforementioned parameters in the design of rigid piles, as the reduction of friction along the interface reduces not only the ultimate load but also the stiffness of the soil-pile response.

PERFECTLY MATCHED LAYER (PML) FOR TRANSIENT WAVE PROPAGATION IN A MOVING FRAME OF REFERENCE

In relation to the development of a Rolling Wheel Deflectomet er (RWD), which is a non-destructive testing device for measuring pavementdeflections, a finite element model for obtaining the soil/pavement response is developed. Abs orbing boundary conditions are necessary in order to prevent reflections of the waves propaga ting through the soil due to the dynamic loading. The Perfectly Matched Layer (PML) has prov en to be highly efficient when solving transient wave propagation problems in a fixed mesh. H owever, since the RWD is operating at traffic speeds, the load is moving with high speedand a formulation in a moving mesh is therefore more convenient. In this paper, a formulat ion of the PML is developed in the moving frame of reference. Numerical results are presented f or a single layer and a double layer half space, respectively, subjected to a moving load o different velocities.