Dear all,

I am trying to simulate the hydraulic fracturing operation using the XFEM performed on Abaqus.

The model is subjected to the far-field stresses also called borehole stresses, Sxx-Syy Fig.1.

However, in the actual field, these stresses vary with depth. They are increasing with depth and they will affect the overall results (Fracture aperture, and injection pressure).

Based on the example that is available on ABAQUS documentation, I defined these stresses as predefined initial stresses Figure.2. Firstly, I assumed these stresses as constant.

Is it possible to obtain the increasing of these stresses with depth? We have to write a user-defined material or something like that to obtain this variation in the stresses. Could you please refer to an example in the literature or in ABAQUS documentation if is available to incorporate that in my simulations?


Best,