hi everybody.

 I am interested to implement  tresca failure criteria in my plastic material model (ABAQUS/standard) using UMAT subrountine which is avaiable in ABAQUS code but it is primaryly made for Mises failure , so i made few attempt to modified it for tresca , but it did not work out, so if anyone have any idea , please guide me. 

thanks

prashant sharma 

When an electric voltage is applied across the thickness of a thin layer of an dielectric elastomer, the layer reduces its thickness and expands its area. This electrically induced deformation can be rapid and large, and is potentially useful as soft actuators in diverse technologies. Recent experimental and theoretical studies have shown that, when the voltage exceeds some critical value, the homogenous deformation of the layer becomes unstable, and the layer deforms into a mixture of thin and thick regions. Subsequently, as more electric charge is applied, the thin regions enlarge at the expense of the thick regions. On the basis of a recently formulated nonlinear field theory, this paper develops a meshfree method to simulate numerically this instability.