GEOS: Pre- and Post-Tensioning
The SOFiSTiK module GEOS is a tool for the definition of tendon geometry, stress sequences and load case assignment.
GEOS supports any necessary input for any geometry (straights, splines, 3D curves) and any stressing sequence (pre-tensioned, post-tensioned, internal, external). All the relevant losses such as wedge slip, friction, wobble are part of the standard results provided as output. As a result load cases are prepared wherein one or several tendons act as a load on the structure. When analyzing this load case the pre-stressing action itself is divided into two parts ? the primary and the secondary effects. The results of both effects can either be handled as a couple or individually as it suits the selected design code.
When defining the geometry specific boundary then the definitions are set by the user. These boundary conditions can be at the begining and end of the tendon (independent from any element subdivision) the top and bottom position together with radius, straight parts with a specific length, tangents to the geometry etc.
GEOS provides specific design results. The stressing sequence is described in detail with any relevant information concerning the actual jacking. The tendon as well as the duct geometry are both displayed as an offset to the element bottom giving information about the stirrups and the detailed duct position.
GEOS is available as a version for beam elements (GEOS-B) , and a version for plate/shell elements (GEOS-P). A combined package is available for a reduced price as well.
The input for GEOS will be handled via CADINP or the interactive graphical user interface "TENDON".
TENDON: Interactive generation of tendon/strand geometry
The geometry definition within TENDON is based on three general default geometries (straight, stretched, 3D spline) which enable the definitions of complex geometries such as combinations of curvature in plan and elevation. The result of the interactive part is on one hand a set of graphical and numerical output (see figure below: tendon force including losses) as well as a set of data in the database. An export/import from and to the CADiNP data for further work in the ASCII file is certainly available as well.
TENDON can then be used as a control tool for the definitions done within CADiNP.
CADiNP: Parametric input of pre-stress data
The ASCII based CADiNP tool is a powerful way for defining any SOFiSTiK data using many features for parametric and therefore flexible tools. For pres-stressing definitions one can make advantage of grouping repetitive actions in loops reducing the often big amount of input to only a few lines.
A typical application will be a balanced cantilever construction where many individual tendons need to be defined. Specifying only the first few tendons interactively and then multiplying this basic information for all other tendons will be the most efficient way . It can be observed that working with CADiNP requires a bit more learning at the beginning, but represents one of the main advantages of SOFiSTiK.
Certainly all GEOS data defined within CADINP can be imported into TENDON for checking purpose or modification.
