To ensure better horizontal deformation resistance

the pile foundation of integral abutment jointless bridges (IAJBs) should be designed as flexible pile. However

the calculation algorithm of flexible pile in relevant codes in China is mainly applied to the laterally loaded pile

and whether it can be used to identify the flexible pile for IAJBs remains a tricky issue to be studied. Therefore

in order to study the aseismic performance and interaction mechanism of the single pile-soil system

three concrete model piles with different lengths were tested under horizontal low-cycle reciprocating displacement based on a specially designed pile deformation measurement method. The result shows that the earliest cracking position of concrete pile is between 3~6 times of pile diameter. The deeper the pile is buried

the better the effect of pile-soil interaction with a deeper location of the deformation characteristic point. Meanwhile

stiffness of pile-soil system

horizontal ultimate bearing capacity and aseismic performance is improved with burial depth increased. The result also indicates that

when the pile-soil system reach the elastoplastic stage

the flexible performance of the pile will gradually degenerate from the elastic pile to the rigid pile. Furthermore

the provisions in relevant codes in China are not safe enough when evaluating the flexural performance of the pile foundation of integral abutment jointless bridges. Hence

it is recommended to use the Broms method for the benchmarking calculation in practical engineering.