The formulation is based on the concept of structural admissibility of load-bearing contact networks. A reduced structural parameter is introduced that measures the distance to the loss of admissible force-transmitting configurations. The work distinguishes between purely geometric coordination and effective load-bearing coordination, thereby linking contact-network mechanics, force-chain stability, and energetic stability within a unified structural framework. Stable granular configurations are interpreted as admissible minima of a reduced energetic state function, while instability emerges through the progressive loss of effective load-bearing connectivity and the disappearance of stabilizing structural curvature. The manuscript forms part of a broader series on energetic stability and structural admissibility in granular systems. Related foundational work: Wittig, M.H. (2026) “Energetic stability and structural admissibility in granular systems” https://doi.org/10.5281/zenodo.20056042
Manfred Wittig (Sun,) studied this question.