Seismic behavior of a dolphin-type berth subjected to liquefaction induced lateral spreading: 1g large scale shake table testing and numerical simulations

摘要

The effects of liquefaction induced lateral spreading on the piles of a dolphin-type berth were investigated using 1 g large scale shake table testing accompanied by numerical simulations. For this purpose, various aspects of the response of the soil and the pile group to lateral spreading were considered. The results indicated that large bending moments were induced in the piles during lateral spreading and the downslope piles of the group received greater bending moments than the upslope one. The monotonic components of bending moments in the piles were reasonably predicted by the displacement based numerical approach using p-y springs when they were properly tuned for strength reduction in liquefied soil and the pile position in the group. A three dimensional hydro-mechanical finite element analysis was also undertaken in OpenSees which appropriately reproduced the physical model behavior. Lastly, a comprehensive parametric study on the verified finite element model revealed that the relative density of soil and the amplitude of base excitation can profoundly affect the induced bending moments in piles as well as the pile cap displacements while the effect of pile flexibility was comparably smaller in this regard.