Centrifuge test on single pile with different rigidities in saturated clay under cyclic lateral loading

The centrifuge tests are carried out to investigate the static and cyclic lateral bearing behaviors of single pile with different pile-soil relative rigidities in normal consolidated clay. Under the same soil and pile-buried depth condition, the pile-soil relative rigidity is tuned by adjusting the model pile material and the section geometric parameter. The comparison group includes rigid pile, flexible pile and semi-rigid pile. Before the loading tests, the cyclic T-bar tests are performed, with the results indicating that the clay strength profile and softening parameter of each test are consistent, verifying the reliability of sample preparation. Both the initial stiffness and the ultimate bearing capacity of the normalized load-displacement curve of piles increase with the increase of pile-soil relative rigidity factor, which indicates that the pile-soil relative rigidity factor can be used to describe the static bearing behavior of the laterally loaded pile. Although the rigid pile is more affected under cyclic loading, its cyclic stable stiffness is still significantly larger than that of a flexible pile. The ratio of cyclic stable stiffness to static stiffness decreases under the increasing pile-soil relative rigidity factor. From the perspective of long-term stiffness control, increasing the pile diameter is not conducive to stable performance, which can be improved by increasing the pile-buried depth. © 2021, Editorial Office of Chinese Journal of Geotechnical Engineering. All right reserved.