Centrifugal model test is designed to simulate basal heave failure of narrow-deep foundation pit in soft clay. The bending moment and horizontal displacement of retaining wall

the earth pressure distribution as well as basal failure mechanism of excavation at different groundwater levels are analyzed. Based on fundamental parameters and excavation procedures of the centrifugal model test

a finite element model is established to analyze the basal heave stability factors and failure modes of foundation pit

comparing with the centrifugal test results. The results of centrifugal model test show that

with the excavation depth increases and groundwater level rises

the bottom uplift and deformation increase. Horizontal displacement towards pit occurs at the bottom of retaining wall

because of the lateral restraint reduction and greater uplift

at the same time

the axis force of internal struts increases. Eventually

retaining wall rotates around a braced point of its own

resulting in a skirting failure. The results of numerical simulation show that

with the increase of groundwater level outside the pit

the safety factor of basal heave stability gradually reduces. When foundation pit collapses due to basal heave failure

the uplift displacement at bottom is greater. The basal failure mechanisms revealed by centrifugal model test and numerical simulation are similar.