Physical and Numerical Modelling of Grouting Induced Enlarged-Base Pile

The grouting induced enlarged-base pile is an uplift pile combining conventional enlarged-base pile with post-grouting technique. This type of uplift pile has great value in engineering practice for its higher uplift bearing capacity and less material used. This paper will discuss the uplift bearing capacity and failure mechanism in depth from two aspects, including the model experiment and finite element modelling (FEM). Considering the grouting induced enlarged- base pile, experimental model was developed to investigate the uplift capacity of the enlarged base. The load-displacement curves for enlarged bases of different sizes were obtained under the overburden pressure corresponding to a certain depth. Meanwhile, the experiment was numerically investigated via FEM and the results are consistent with the experimental data. It is found that the degree of increase of uplift bearing capacity becomes greater as the length ratio of the enlarged base to the pile or the diameter ratio of enlarged base to pile increase.