Imposed line deformation occurs when a line is displaced despite a defined support. This is the case of a foundation settlement, for example.
In order for the imposed deformation to take effect on a line, it must be supported in the direction of the deformation. Imposed deformations can be defined for each of the three translational degrees of freedom or the local rotational degree of freedom, but only in the direction in which the line has a support.
Imposed displacements have a positive effect when pointing in the direction of the positive axes of the coordinate axis system of the support. The imposed rotation has a positive effect when it is rotated clockwise about the positive local axis of the line according to the right-hand rule.
Usage in RFEM
In the program, a distinction is made between imposed displacement and imposed rotation.
To enter the imposed displacement, it is necessary to know and define the values of the displacement at the line start and at the line end. A linear distribution is assumed between these values.
The imposed rotation describes a forced rotation about the longitudinal axis of the line. To enter the imposed rotation, it is also necessary to define the existing rotations at the line start and at the line end.