Centrifuge Modeling on the Behavior of Sheet Pile Wall Subjected Different Frequency Content Shaking

Sheet pile wall is often used as a retaining system at the riverbank owing to its economy, convenience, and constructability. The soil deposit nearby river is composed of alluvium soil with a high ground water level. Therefore, the soil deposit usually has high potential of liquefaction. The shaking may induce soil liquefaction when the earthquake occurs, causing the sheet pile wall damage or failure. Each earthquake has different frequency content and acceleration amplitude in real conditions. Thus, it would lead to different behavior of the wall-soil system. In this study, three dynamic centrifuge tests were carried out by NCU geotechnical centrifuge and shaking table under 24 g centrifugal acceleration field. Ottawa sand was used to prepare the liquefiable ground with a prototypical excavation depth of 3 m. The models were subjected to the input motions with different frequency content of 1 Hz and 3 Hz. The horizontal displacement of the sheet pile wall and ground surface were measured by the linear variable differential transformers and surface markers. Test results indicate that the model subjected to input motion with higher 3 Hz content and higher peak base acceleration has higher excess pore water pressure excitation and excitation rate. The shallow layer soil in the backfilled area of it achieved initial liquefaction. Moreover, it also has larger lateral displacement of sheet pile wall and ground surface as compared to the others.