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~ETHSFE

 

~ETHSFE, LKEY, Lab, UTER, FACT, WFACT

Calculates and applies a ground pressure on selected beam, shell and surface elements

PREP7: GEOTECHNICAL MODULE: Earth Pressure

LKEY

Element face on which the pressure is applied. Only faces 1 and 2 are available.

Lab

Label identifying the type of pressure to be applied:

Lab	Description
ACT	Active pressure (by default).
WGH	Weight of the terrain.
PAS	Passive pressure.
RST	At rest pressure.

UTER

Number of the terrain that will be used.

FACT

Factor that will multiply the earth pressure or terrain weight (by default = 1.0).

WFACT

Factor that will multiply the water pressure (by default = 1.0).

Notes

- The pressure is calculated based on the data of the terrain, which is defined with the ~TERDEF command.

- The pressure is applied on beam elements and 2D surface elements as a normal and tangential pressure in the indicated element face. On shell and 3D surface elements elements, the pressure is applied as a normal pressure on the indicated face and a set of forces on the nodes that is equivalent to the tangential pressure. The face number will be positive if the ground and this face are in contact with each other, and it will be negative if the ground is contact with the opposite face.

- The pressures are calculated as specified in the Terrain definition (~TERDEF command). Pressure coefficients from the database will be used unless the Coulomb’s Theory calculation is specified to be used. For further details about the theoretical explanation and the adopted hypothesis, see the CivilFEM Theory Manual.

- The ground pressure can be applied on the following elements:
2D Beam Elements: BEAM3, BEAM23, BEAM54
3D Beam Elements: BEAM4, BEAM24, BEAM44, BEAM188, BEAM189
Shell Elements: SHELL43, SHELL63, SHELL93
Surface Elements: SURF153, SURF154

- The terrain thickness used for BEAM elements will be taken from the cross section geometry defined in the Beam Property. For SURF153 elements, the thickness will be obtained from the respective real constant.

- For applying pressures on solid elements, see the ~ETHSF command.

- This command is available in PREP7 and SOLU processors.

Menu Paths

Main Menu > Civil Preprocessor > Geotech. Mod. > Earth Pressure > Beam, Shells, Surf

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