The Seismic Performance of Piles in Waterfront Applications

Recent earthquakes have highlighted many seismic hazard concerns for ports worldwide. Waterfront structures at ports are commonly constructed utilizing pile-supported wharves in combination with rock dike structures retaining a hydraulically placed backfill. Seismic damage has generally been attributed to weak soils that are often prevalent in the marine environment (e.g. liquefiable sands, sensitive cohesive soils) and/or insufficient ductility of pile-wharf deck connections. The design of a seismically resilient wharf requires an understanding of its performance during design level earthquakes. Due to the complex nature of pile-supported wharves, state-of-the-art centrifuge modeling techniques are being used to better understand their seismic performance. The performance of pile-supported wharves in carefully controlled, large-scale centrifuge tests is being monitored through the extensive use of instrumentation. The results of the centrifuge tests are: 1) being compared to the results from standard-of-practice methods of design, and 2) being used to validate the use of sophisticated numerical programs for the modeling of seismic soil-structure interaction. This paper summarizes aspects of the construction, instrumentation, and testing of the models. Results on the seismic performance of a model is also presented, as well as the results of a comparison between the measured centrifuge seismic performance, and the seismic performance estimated using a standard-of-practice design method.