Skip to Main content Skip to Navigation
Theses

Contributions a l'étude d'un modèle de mésofissuration : application au comportement d'un grés

Abstract : To study crack damage of quasi brittle rocks, a mesomechanical model with two versions (secant matrix and incremental) has been developed. This model allows a micro-macro transition in order to improve physical comprehension of quasi-brittle behaviour and hence the formulation of phenomenological models. To reach this goal, physical mechanisms of brittle damage are studied first. The sliding crack model is finally adopted. After summarising the basic concepts of micro-macro approaches, different theoretical models used to estimate effective properties of media containing open or closed mesocracks are analysed. Their predictions are evaluated and compared with various direct numerical simulations established with a displacement discontinuity method. Those works are needed for study of the brittle mesocracking damage. The secant matrix model is limited to traction or triaxial compression loading. The strain mechanisms considered are nucleation, the mesocracks growth and the sliding on closed mesocracks faces. The
analysis and the test of this model predictions on a sandstone allow to establish a basis for the development for an incremental formulation of the model. This approach authorises the description of materials response under more general loading paths : cyclical loading paths, proportional paths, lateral extension, etc.. The incremental version of the purposed model allow to analyse some specific aspects of the microcracked materials like the unilateral contact. Finally, the study of unloading paths confirm the key role of sliding by exhibiting residuals strains or hysteresis loops.
Document type :
Theses
Complete list of metadatas

Cited literature [117 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00174773
Contributor : Vincent Renaud <>
Submitted on : Tuesday, September 25, 2007 - 11:37:04 AM
Last modification on : Tuesday, November 24, 2020 - 2:18:05 PM
Long-term archiving on: : Thursday, April 8, 2010 - 8:53:49 PM

Identifiers

  • HAL Id : tel-00174773, version 1

Collections

Citation

Vincent Renaud. Contributions a l'étude d'un modèle de mésofissuration : application au comportement d'un grés. Sciences de l'ingénieur [physics]. Université des Sciences et Technologie de Lille - Lille I, 1998. Français. ⟨tel-00174773⟩

Share

Metrics

Record views

196

Files downloads

295