Explicit-VUMAT.rar_explicit_explicit vumat_vumat_vumat material

Answer ID

3123

Last Updated

03/11/2011 01:38 PM

Access Level

Cust wo support

Abaqus/Explicit VUMAT for the simulation of damage and failure in unidirectional fiber composite materials

Answer

(The following applies to any Abaqus release.)

1. Introduction

This Answer describes a constitutive model for unidirectional fiber reinforced composites for use in

Abaqus/Explicit. The constitutive model for the fiber is based on Hashin’s failure criteria for unidirectional fiber

composites (Hashin, 1980). For the matrix material, a constitutive model based on Puck’s action plane

theory (Puck, 1998) is used. Other well-known failure criteria can be incorporated with simple modifications

to the existing code. The model has been implemented as a VUMAT user subroutine and is attached below.

It is assumed that the elastic stress-strain relations are given by orthotropic damaged elasticity. Referred to

a local coordinate system (OX

1

axis aligned with the fiber directions, and the OX

3

axis

normal to the plane of the lamina, the elastic relations take the form:

(1)

fc

, associated with fiber tension and compression

mt

damage variables according to:

(3)

mt

mc

in the definitions of the shear moduli are introduced to control the loss of shear

2.2. Hashin and Puck failure criteria

The damage variables associated with fiber/matrix failure in tension/compression are set to one

instantaneously when the corresponding failure criterion is reached. We use the following generalization of

Hashin’s quadratic failure criteria (Hashin, 1980) and Puck’s action plane model (Puck, 1998):

Tensile fiber mode: s

11

> 0:

(5)

Compressive fiber mode: s