2D Result Lines were first implemented in Structural Designer release 2019 (released Mar 2019) allowing the engineer to investigate sectional forces around openings in concrete walls for example. Subsequent releases have continually enhanced this feature, adding interactive concrete section design in release 2019 SP1 and enhanced design forces in release 2019 SP2.
See this video demonstrating result lines in action.
The Tekla Structural Designer 2020 release further enhances the Interactive design using Result lines feature to add the saving of both the reinforcement and manually added/adjusted design forces defined in the interactive design dialog.
Key aspects of Interactive design using Result Lines are:
The Interactive Design option is accessed from the right-click context menu for Result Lines as shown above. The engineer then chooses from wall or column section design options and the appropriate Interactive section design dialog is displayed.
The wall length/ column depth considered is the Result Line length. The design dialog features full interactive manual selection of both lateral and vertical reinforcement, Interaction Diagrams and auto-design and check options, just as for a regular wall/ column section. All edits to the reinforcement settings are now saved when the Interactive design dialog OK button is clicked (please note that changes to concrete column/wall size is not saved).
Result Lines are not constrained to cross sections in the horizontal plane - vertical sections can be used above/between openings to investigate forces and reinforcement requirements in “coupling beams”.
The section design always considers the main bars (running perpendicular to the cross section) as being on the inner layer, from a design perspective this will tend to be conservative but the engineer should give this some consideration when working with non-horizontal sections.
Additional Design Cases and Adjustments - the Result Line forces are listed in the “Additional Design Cases” page. These forces can be manually added to and adjusted. All additions/ adjustments are now saved when the Interactive design dialog OK button is clicked.
There are three potential “Design Moment” adjustments for each direction:
Set an imperfection eccentricity allowance (Eurocode only). This is added to the analysis moment.
Apply an amplification factor to allow for Second Order Effects (could also be considered as a way to introduce an extra factor of safety)
Apply a minimum moment check in one or both directions (the calculation of this is specific to the Head Code set and is a function of the section dimension “h” in the direction considered).
When applied, the resulting adjusted design moment is automatically calculated and displayed in the dialog.
The adjustment values and options can be applied manually to individual Cases and also quickly in a single operation to all Active cases (those with “Active” option checked on) via the [Design Moment Factors…] button as shown above.
Note that the design does not consider the reinforcement specified in wall properties - only that which is defined in the Interactive design dialog.
Currently the feature is not linked with Reports and so it is envisaged output will be via screenshots of the interactive design and check results dialogs.