ABAQUS UMAT compatiblity

Hello,

I made UMAT for some constitutive model.

The everything, in the UMAT code, including constitutive equations and consistent tangent operators are correct.

The problem is that UMAT works at some simple 2D/3D FE model, but sometimes not working in some 3D complex FE model.

The analysis ends due to error 'TOO MANY ATTEMPTS MADE FOR THIS INCREMENT' in msg file.

In data file, only one warning comes out.

"The aspect ratio for 1603 elements exceeds 100 to 1. The elements have been identified in the element set WarnElemAspectRatio."

Have you encountered this situation? Do you know the exact reason for this phenomenon??

Regard,

Kwangmin, Lee