Centrifuge Model Tests on Failure Mechanism of Dual Structure Slope under Gradual Excavation Condition
Centrifuge Model Tests on Failure Mechanism of Dual Structure Slope under Gradual Excavation Condition
Gradual slope excavation is a common engineering practice, but it carries significant instability risks. Most previous researches have put their focus on homogeneous slopes, while natural slopes are often heterogeneous. Therefore, studying the failure mechanism of heterogeneous slopes under gradual excavation is crucial. In this study, excavation centrifuge model tests are conducted on both a heterogeneous slope model containing clay and sand and a homogeneous one with clay as control. In the tests, excavation was performed in five steps, and an image-based measurement system is used to capture full-field displacement history of the slopes during the tests.
The results show that the slopes both have a part with similar range occurring rapid failure during excavation. The dual structure slope landslides at excavation depth of 150mm while failure in the pure clay one appears when excavation depth is 120mm. in a similar range during gradual excavation. The two slopes share similar failure mechanism which can be explained by the coupling effect of deformation localization and local failure. Dual structure significantly affects the slopes response under excavation. It brings difference in deformation distribution and therefore changes the slip surface pattern and location. The dual structure also alters the slope failure process by slowing the rate of deformation development and enhancing the slopes bearing capacity against excavation, while at the same time reducing its resistance to deformation localization.
Yueyan Hao; Ga Zhang
11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)
Special Session 8: Nature-based solution for sustainable geotechnical systems
https://doi.org/10.53243/ICPMG2026-92