Effective-stress nonlinear dynamic analyses (NDA) were performed for piles in liquefiable sloped ground to assess how inertia and liquefaction-induced lateral spreading combine in long-duration vs. short- duration motions. A parametric study was performed using input motions from subduction and crustal earthquakes covering a wide range of motion durations. The NDA results showed that the pile demands increased due to liquefaction-induced lateral spreading compared to nonliquefied conditions. The NDA results were used to evaluate the accuracy of the equivalent static analysis (ESA) recommended by Caltrans/ODOT for estimating pile demands. Finally, the NDA results were used to develop new ESA methods to combine inertial and lateral spreading loads for estimating elastic and inelastic pile demands.
Subjects: Pile, Liquefaction, Lateral Spreading
Author: Arash Khosravifar, Assistant Professor, Portland State University, Portland, OR, Jonathan Nasr, Graduate Student Researcher, Portland State University, Portland, OR
Publisher: DFI