

SIGMA/W is formulated for 2dimensional plane strain or axisymmetric problems using a small displacement, small strain, incremental load formulation. For each load step, incremental displacement at each node resulting from the incremental load is computed and added to the displacement at the beginning of the load step to give the total displacement. For soil models with nonlinear material properties, SIGMA/W solves the equations iteratively using the NewtonRaphson technique; soil properties are updated every iteration until a converged solution is achieved.
You can simulate the filling and excavation of materials by activating or deactivating regions at various stages of the construction process. SIGMA/W can be used with SEEP/W for uncoupled consolidation analyses. SEEP/W calculates transient porewater pressure changes due to the applied load, while SIGMA/W calculates deformations resulting from the porewater pressure changes. 
FEATURES
 Analysis types include drained total and effective stress, undrained total and effective stress, 2D plane strain, 3D axisymmetric, consolidation and swelling, and insitu stress.
 Constitutive soil models include linearelastic, anisotropic linearelastic, elasticplastic, and Modified Camclay.
 Boundary condition types include X and Y displacements, forces, pressures, and spring constants, as well as selfweight gravity loading.
 Structural beam and bar elements for soilstructure interaction.
 Staged loading for fill placement or earth removal.
 Uncoupled volume change due to porepressure changes.
 Fullycoupled stresspore pressure analyses.
 Userdefined AddIn constitutive models.






