Numerical study of shear band instability and effect of cavitation on the response of a specimen under undrained biaxial loading

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:51

Article

Sieffert, Y.¹  Buzzi, O.²  Collin, F.³ 

[1] Univ Grenoble Alpes, CNRS UMR 5521, UJF, Grenoble INP,3SR, F-38000 Grenoble, France

[2] Univ Newcastle, Prior Res Ctr Geotech & Mat Modelling, Callaghan, NSW 2308, Australia

[3] Univ Liege, Inst Mecan & Genie Civil, Dept ArGEnCo, B-4000 Liege, Belgium

关键词: Localization;    Dilation;    Cavitation;    Biaxial test;    Second gradient;    Undrained;   

DOI  :  10.1016/j.ijsolstr.2014.01.009

来源: Elsevier

【 摘 要 】

This paper presents an extension of the local second gradient model to multiphasic materials (solids particles, air, water) and including the cavitation phenomenon. This new development was made in order to model the response of saturated dilatant materials under deviatoric stress and undrained conditions and possibly, in future, the behavior of unsaturated soils. Some experiments have showed the significance of cavitation for the hydromechanical response of materials. However, to date and as far as we are aware, no attempt was made to implement the cavitation as a phase change mechanism with a control of pore pressure. The first part of the results section explores the effects of permeability, dilation angle and loading rate on the stability of shear bands during a localization event. The reasons underlying the band instability are discussed in detail, which helps defining the conditions required to maintain stability and investigating the effects of cavitation without parasite effect of materials parameters or loading rate. The model showed that, if a uniform response is obtained, cavitation triggers localization. However, in case of a localized solution, cavitation follows the formation of the shear band, with the two events being quite distinct. (C) 2014 Elsevier Ltd. All rights reserved.

【 授权许可】

Free