Function
- Enter the internal member forces in the structure due to external loads for linear analysis. The member forces are calculated using Initial Force Control Data.
- Initial member forces are generated from member forces due to a specific load combination, as controlled from Load > Initial Force > Small Displacement > Initial Force Control Data. After Initial Force Control Data has been completed and analysis has been performed, the initial (internal) forces calculated can be checked in Results > Result Tables > Initial Element Force table.
- Initial Element Forces are used to calculate geometric stiffness in general linear analysis. This function includes geometric stiffness in linear stiffness. It is applied to linear static, linear buckling, eigenvalue, response spectrum and time history analyses.
- In analyses such as thermal analysis, geometrically nonlinear analysis, material nonlinear analysis, and pushover analysis, the inputted "Initial Element Force" is ignored or not considered.
Call
From the main menu, select [Load] tab > [Type : Misc.] > [Initial Forces] group > [Small Displacement] > [Initial Element Forces]
Input
Axial-i : Axial force at i-end
Shear(y)-i : Shear force in the ECS y-dir at i-end
Shear(z)-i : Shear force in the ECS z-dir at i-end
Torsion-i : Torsional moment at i-end
Moment(y)-i : Moment about ECS y-dir at i-end
Moment(z)-i : Moment about ECS y-dir at i-end
Axial-j : Axial force at j-end
Shear(y)-j : Shear force in the ECS y-dir at j-end
Shear(z)-j : Shear force in the ECS y-dir at j-end
Torsion-j : Torsional moment at j-end
Moment(y)-j : Moment about ECS y-dir at j-end
Moment(z)-j : Moment about ECS z-dir at j-end