<p> DDFS3D is a set of open-source code which utilizes DDM (displacement discontinuity method), FSM (fictitious stress method) and the hybrid of DD-FS to efficiently and accurately simulate fractures embedded in large 3D domains. DDFS3D is developed in Fortran language with a number of modules to hold subroutines and variables. CPU<br>
acceleration with OpenMP library is in place. Boundary conditions, covering a range of stress, displacement and the hybrid of the two, are supported by DDFS3D. Far-field (<em>in-situ</em>) stress can also be applied. The joint element is available to account for the elastic behavior of fracture<br>
gouge/asperity in normal and tangential directions. Note that the current version of DDFS3D does not provide any pre- or post-processing functions. Users have to prepare the mesh beforehand and rely on other programs/codes to visualize the results. In addition, the OpenMP library has to be<br>
compiled together with the source codes of DDFS3D to enable CPU acceleration. Otherwise, DDFS3D will be run in a serial manner.<br>
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