Effects of the use of battered piles on the dynamic response of structures supported by deep foundations

Abstract

Inclined piles are frequently indicated in those cases in which foundations are expected to be subjected to important lateral loads. Nevertheless, the use of battered piles in seismically active regions has been considered detrimental and became highly discouraged in many codes (e.g. [1]) after a series of earthquakes in which deep foundations with raked piles showed a poor performance. In recent years, inclined piles have recovered their popularity. Indeed, several studies have shown the beneficial role of battered piles on the seismic response of the structure [2 – 6].

Up to the author's knowledge, only Gerolymos et al. [3] and Giannakou et al. [7] have analysed numerically the influence of using deep foundations with inclined piles on the dynamic response of the supported structures, while many authors have analysed the dynamic behaviour of the foundation itself. The influence of using inclined piles on the dynamic behaviour of the dynamic response of the superstructure remains a question that needs further research. Aiming at contributing to fill this gap, in this paper, a procedure based on a substructuring methodology [8] is used to obtain the response of the superstructure in terms of the effective period and the maximum shear force at the base of the structure per effective earthquake force unit for several configurations of 2 x 2 pile groups comprising inclined elements in direction of excitation.