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The time is a new quantity in TDA analysis. First of all, the user defines global time as one of the parameters of each construction phase. This time is be assigned to the current stage. Additional time nodes are generated for TDA, see local history of a 1D member. Therefore, number of time nodes is greater than the number of stages. Additional time nodes required for proper accuracy of creep analysis can be generated in the dialog Time axis edit. Logarithmic scale is used for the time axis drawing in the dialog Time axis edit.
First of all the user inputs the global time of the first construction stage, which is the first time node on the "Time axis of construction stages". For example if we assume (local) time of casting of first macro –3 days, then it is recommended to input time of the first stage +3 days (but it is not necessary). If we do so, the time of first construction stage in global time axis will be still +3 days also after merger of the local axis to the time axis of construction stages. The origin of the time axis is always moved to the time of casting of the first member! Now we have "Merge of local time axes" (time axis of stages + local time axes): t0, t1, t2, …, ti, tj, … tn, and we need to generate detail time nodes ti+k, k=1,2, … until ti+k<tj (to ensure the required accuracy of creep analysis). It is done automatically.
The Time axis edit dialogue consists of three parts:
graphical window,
property window,
input window.
Graphical window (of the Time axis edit dialogue)
The graphical window shows all the information related to the time axis:
number of subintervals,
stage node number,
time axis of construction stages,
merge of local time axis,
detail time axis,
number of all subintervals.
The graphical window supports standard features of SCIA Engineer graphical windows:
[Ctrl] + [Shift] + right-click and drag to zoom in and out the drawing,
[Shift] + right-click and drag to move the drawing.
For more information, refer also to the introductory text to this chapter and look at the procedure at the end of the chapter.
Property window (of the Time axis edit dialogue)
This window enables you to show or hide required information in the graphical window. It is also possible to adjust colours of individual diagrams and set the scale of the text and the picture.
Please, read also the procedure at the end of this chapter.
Input window (of the Time axis edit dialogue)
Here the number of subintervals can be input for the selected interval.
Open the service Construction stages.
Start function Time axis.
The Time axis edit dialogue is opened on the screen.
You may:
review the input data: to display or hide the required axis, just click the appropriate View checkbox in the property window of the dialogue. To change the colour of the required axis, click the colour box in the property window of the dialogue, a "three-dot-button" becomes enabled, press it and select the required colour.
change the number on subintervals: On the axis Number of subintervals select the interval you want to edit. The input box in the bottom right corner of the dialogue becomes accessible and shows the currently defined number of subintervals for the selected interval. You may change the number.
When ready, close the dialogue.
Note: A small number of subintervals is suitable for the first analysis and tuning of the model. The accuracy is not perfect, but the calculation is fast and necessary re-calculations do not take too much of your precious time. Once the model has been tuned, it is highly recommended to increase the number of subintervals in order to obtain satisfactory accuracy of the results.