Learning Forum

[Rana Nasser]

How can I define the allowable bearing capacity of the soil, cohesion, and internal friction when adding material in the engineering data? Or how can I define a soil material in ansys workbench? 

[peteroznewman]

Hello Rana,

There are several material models that mention soil. Use the ANSYS Help window and go to Mechanical APDL > Materials Reference. There are two places to read: 4.3 and 4.9.

4.3. Porous Elasticity

Porous materials such as soils or polymer foams display nonlinear elastic behavior caused by the effect of voids on the bulk modulus of the material during hydrostatic compression.

Compared to the solid portion of the material, voids are relatively compressible, and the effect on the bulk modulus varies according to void proportions. During hydrostatic loading, voids compress or dilate; however, the solid portion of the material remains comparatively stiff, exhibiting little volumetric deformation. As the void ratio of the material changes, the bulk modulus also changes.

4.9. Geomechanics

Geomechanics encompasses the mechanical behavior of soil, rock, and aggregate materials in both their natural and man-made states. Applications for these material models include footings and pilings, tunneling, excavations, seismic events, and compaction or consolidation. 

4.9.2. Cam-clay

The modified Cam-clay plasticity model [3] is based on the critical state concept and is commonly used for soil simulation. The critical state concept is a material phenomenon common in the shear deformation of soils where the stress and volume remain constant after a critical state of deformation, and further loading causes increasing plastic strain but no increase in volume or stress. The Cam-clay plasticity model, combined with porous elasticity, models the effect of voids on the elastic behavior of the material.

Regards,

Peter