Compressive Splitting in Brittle Solids: The Inverse of Wrinkling in Sheets

Abstract

Axial splitting is the dominant failure mode of brittle solids under compression, yet its mechanical origin remains unclear.
We show that clamped loading platens suppress lateral Poisson expansion, generating boundary-induced tensile stresses at the specimen interior -- the compressive analog of wrinkling in stretched sheets.
This mechanism provides a predictive strength law, relating axial splitting to tensile strength, geometry, and confinement pressure.
This is validated against diverse materials ranging from rocks to ceramics, establishing axial splitting as a geometry-controlled elastic process rather than a stochastic flaw problem.