How does Abaqus calculate strain and strain increment from displacement?
How does Abaqus calculate strain and strain increment from displacement?
(OP)
I have two questions concerning strain in Abaqus:
1. In Abaqus CAE, the user can only specify as boundary conditions the applied displacement and time. So how does Abaqus calculate the applied strain and strain increment, especially for non-linear problems where the relation between displacement and strain is non-linear?
2. What is the Jacobian matrix used for in Abaqus? For example, when you run a UMAT subroutine, it needs to pass stress and Jacobian matrix back to Abaqus at the end of every increment. Does Abaqus use the Jacobian matrix at all? Does it use the Jacobian matrix to calculate the strain increment (DSTRAN) that it needs to apply in the next step? If so, how does it calculate DSTRAN ?
1. In Abaqus CAE, the user can only specify as boundary conditions the applied displacement and time. So how does Abaqus calculate the applied strain and strain increment, especially for non-linear problems where the relation between displacement and strain is non-linear?
2. What is the Jacobian matrix used for in Abaqus? For example, when you run a UMAT subroutine, it needs to pass stress and Jacobian matrix back to Abaqus at the end of every increment. Does Abaqus use the Jacobian matrix at all? Does it use the Jacobian matrix to calculate the strain increment (DSTRAN) that it needs to apply in the next step? If so, how does it calculate DSTRAN ?





RE: How does Abaqus calculate strain and strain increment from displacement?
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RE: How does Abaqus calculate strain and strain increment from displacement?
RE: How does Abaqus calculate strain and strain increment from displacement?