Novel evaluation method based on critical arch height as instability criterion for sustaining arch...

Area of Science:

• Geotechnical Engineering
• Soil Mechanics
• Geological Engineering

Background:

• Natural soil arches significantly influence the stability and evolution of sustaining arch locked-segment-type slopes.
• Understanding the formation and locking effect of these soil arches is critical for predicting slope behavior.

Purpose of the Study:

• To investigate the formation process and evolution of natural soil arches in sustaining arch locked-segment-type slopes.
• To analyze the locking control effect of soil arches on slope stability.
• To develop a mechanical model for slope stability analysis based on the soil arching effect.

Main Methods:

• Utilized a self-developed model test device to simulate slope deformation and evolution.
• Observed the continuous formation and progressive destruction of soil arches.
• Developed a critical arch height mechanical model integrating soil arching and limit equilibrium theory.

Main Results:

• The second-formed soil arch exhibited the most effective locking, leading to a peak anti-sliding force.
• The slope's stability was maintained by stress adjustment and the formation of a larger soil arch.
• Destabilization occurred when the ultimate shear strength of the arch foots was exceeded, reaching a critical arch height.

Conclusions:

• The developed critical arch height mechanical model accurately reflects slope stability based on physical tests and real-world data (Xintan slope).
• The findings provide valuable insights for early warning systems for landslides in similar geological conditions.