Dynamic centrifuge tests of arching effect in embankment undergoing basal settlement and water infiltration

Abstract

This paper presents a series of centrifugal shaking table model tests conducted to examine the characteristics of arch action within an embankment subjected to basal settlement and water infiltration. The tests were performed on a flexible and impervious base to simulate the presence of non-liquefiable soft ground and resulting basal settlement, leading to arch action above the basal subsidence. A liquid supply system was utilized to deliver Metolose inside the embankment during centrifugal loading to investigate the effect of water infiltration and saturated condition on arch action. Additionally, dynamic loading was employed to induce soil liquefaction and the relationship between arch action and soil liquefaction was observed. The paper focuses on the arch action throughout the process of initial stress formation, saturation, liquefaction, and post-liquefaction. The experimental results demonstrated that basal settlement underneath an embankment can lead to the development of arch action, and soil liquefaction can occur in the loosened ground caused by basal settlement, which is influenced by saturation and dynamic loading. The analyses of the earth pressure distribution on the bottom of the embankment model provide insights into the mechanism of arching action and its implication for soil liquefaction. Furthermore, the study also investigated the onset of liquefaction and the collapse mechanisms of embankments. The findings suggest that the arching effect plays an important role in the seismic stability of an embankment and can aid in developing more effective design and reinforcement techniques for embankments and levees.