Centrifugal model tests on bearing capacity of uplift piles under deep excavation

Determination of the ultimate bearing capacity of an uplift pile under deep excavation has been paid much attention to by more and more geotechnical engineers. The theoretical analysis of this problem becomes a hot research topic recently. Unfortunately, due to the limitation of in-situ test conditions, it is almost impossible to obtain the ultimate uplift capacity of tension piles under deep excavation from field tests. Accordingly, centrifuge model tests on uplift piles under deep excavation are performed to examine the load transfer characters and the ultimate bearing capacity. The variation of displacement, friction resistance and internal axial force of the uplift piles before and after deep excavation is analyzed. And then the centrifugal model tests results are used to verify the rationality of the FEM and the limit equilibrium method. The calculated results by the two theoretical methods have good agreement with the results of centrifugal model tests.