Scaling laws for rockfall impact fragmentation emerging from diverse lithologies

Area of Science:

• Geosciences
• Rock Mechanics
• Computational Modeling

Background:

• Impact-induced fragmentation is a key process in geosciences, crucial for understanding debris evolution.
• The stochastic nature of fragmentation poses challenges for predicting the resulting debris size distribution.
• Existing models often struggle to capture the complexity across diverse rock types.

Purpose of the Study:

• To develop and validate a discrete element framework for modeling impact fragmentation across various lithologies.
• To investigate the universality of fragment size distributions under different impact conditions.
• To establish a predictive link between impact mechanics, lithological properties, and debris evolution.

Main Methods:

• Development of a discrete element framework to simulate fragmentation mechanics.
• Validation of the model using high-resolution field data from rockfall events.
• Application of a relative breakage index to analyze fragment size distributions.

Main Results:

• Fragment size distributions consistently follow a universal Weibull scaling law, irrespective of lithology or initial kinetic energy.
• A single statistical signature, based on the Weibull law, effectively collapses fragmentation data from diverse rock types.
• The Weibullian signature serves as a proxy for lithological sensitivity to fragmentation.

Conclusions:

• The discrete element framework provides a robust method for predicting debris evolution from impact events.
• The universal Weibull scaling law offers a powerful tool for understanding and modeling fragmentation processes.
• Findings enable improved engineering strategies for hazard mitigation and structural resilience in rocky terrains.