Performance of finned piles as a protection for a 2*2 group pile subjected to liquefaction-induced lateral spreading: A shake table investigation

Different case studies have demonstrated that lateral spreading induced by liquefaction was one of the main causes of severe damage to a significant number of fundamental structures supported on pile foundations in the aftermath of many major earthquakes. Consequently, a series of shaking table tests were performed in this study to evaluate the different responses of a single pile and a group of 2*2 circular piles subjected to liquefaction -induced lateral spreading in sandy soil with an infinite inclined slope, as well as compare the response of this pile group in the presence of three different types of protection piles. Protection piles included circular piles upstream, finned piles downstream, and circular piles upstream. The instrumentation results indicate that using finned protection piles with the same cross-sectional area as circular piles demonstrated superior performance in disturbing the soil flow and significantly reduced (about 24-50%) the lateral force exerted on the main piles. The dependence of pile response on the location of protection piles relative to group piles was also investigated through a comprehensive comparison.