Ho, Cheng-EnCheng-EnHoJIUNN-SHYANG CHIOU2025-08-282025-08-282025-07-2918611125https://www.scopus.com/record/display.uri?eid=2-s2.0-105012188617&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/731687This study derives theoretical solutions for the lateral response of a scoured fixed-head pile in elastoplastic soil and investigates the effects of soil nonlinearity and foundation exposure on the pile’s ductile behavior. The theoretical model considers both pile plastic hinging, assuming the pile section follows a bilinear moment–curvature relationship, and soil plasticity, assuming elastoplastic behavior. The ultimate state of the pile–soil system is determined by either pile-head bending failure or in-ground plastic hinging. Examples are presented to demonstrate the application of the proposed solutions to derive theoretical pushover curves, the accuracy of which is validated by comparing them with numerical and experimental results. In addition, the examples show that with increasing scour depth, the possibility of the occurrence of in-ground plastic hinging increases, but the effect of soil nonlinearity decreases. This study further conducts a parametric investigation to examine the effect of soil nonlinearity on the displacement ductility capacity and system overstrength ratio. The results indicate that the normalized yield moment can be regarded as a factor normalizing the effect of soil nonlinearity. A higher normalized yield moment value indicates a more significant effect of soil nonlinearity. This can cause increased displacement ductility capacity and a reduced system overstrength ratio.falseDuctilityPushover curveScoured fixed-head pileSoil nonlinearityWinkler-beam modeljournal article2-s2.0-105012188617