Mechanism by which a frictionally confined rod loses stability under initial velocity and position perturbations

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:50

Article

Su, Tianxiang¹  Wicks, Nathan²  Pabon, Jahir²  Bertoldi, Katia^1,3 

[1] Harvard Univ, Sch Engn & Appl Sci, Cambridge, MA 02138 USA

[2] Schlumberger Doll Res Ctr, Cambridge, MA 02139 USA

[3] Harvard Univ, Kavli Inst Bionano Sci & Technol, Cambridge, MA 02138 USA

关键词: Buckling;    Instability;    Friction;    Confined elastic rods;   

DOI  :  10.1016/j.ijsolstr.2013.03.017

来源: Elsevier

【 摘 要 】

We present a theory to reveal for the first time the distinct mechanisms by which a compressed rod confined in a channel buckles in the presence of dry friction. Contrary to the case of a frictionless contact, with friction the system can bear substantially enhanced compressive load without buckling after its stiffness turns negative, and the onset of instability is strongly affected by the amount of perturbation set by the environment. Our theory, confirmed by simulations, shows that friction enhances stability by opening a wide stable zone in the perturbation space. Buckling is initiated when the applied compressive force is such that the boundary of the stable zone touches a point set by the environment, at a much higher critical load. Furthermore, our analysis shows that friction has a strong effect on the buckling mode; an increase in friction is found to lead to higher buckling modes. (C) 2013 Elsevier Ltd. All rights reserved.

【 授权许可】

Free