Exploring the regularizing traits of microstretch continua

Fundamental Research Project, FWF 10.55776/PAT2272725
Start: March 2026

Cohesive-frictional materials such as concrete, rock, and soils play a crucial role in engineering, yet accurately modeling their highly nonlinear and failure-prone behavior remains a major challenge. Conventional numerical approaches often suffer from pathological mesh sensitivity, leading to non-objective results. This project explores the potential of the microstretch continuum -- a special case of Eringen’s micromorphic theory -- as a physically motivated regularization framework. Unlike the micropolar continuum, the microstretch model incorporates both microrotations and an additional dilation mode, which may prevent strain localization even in mode I failure. By deriving the conditions for loss of ellipticity and implementing the microstretch formulation in finite element software, this study provides the first systematic assessment of its regularizing capabilities. The findings aim to establish the microstretch continuum as a robust and thermodynamically consistent approach for modeling material failure.