Creating Parametric Cross-Section
The stand-alone program SHAPE‑THIN determines characteristic values and stresses of any thin‑walled cross‑sections. Graphic tools and features allow for modelling complex cross‑section shapes. In addition to the graphical input, it is also possible to enter the data in tables. As an alternative, you can import a DXF file and use it as a basis for further modelling. Also, each cross‑section can be entered using the cross‑section library of Dlubal Software and combined as a part with the user-defined elements.
Frequently, there is the requirement to create cross‑section series, meaning the same cross‑sections with different dimensions. Parameters allow you to quickly and easily modify the cross‑section dimensions. The parameters can be used in formulas to determine a numeric value. You can edit the formulas using Formula Editor. If a parameter is changed in the parameter list, the results of all formulas using this parameter are adapted.
The parameters are managed in the parameter list. It can be opened by clicking the [Edit Parameters] button in the toolbar of the input table or in Formula Editor.
The parameter name (Column A) should not contain any spaces and may only be assigned once. This parameter is used to address the parameter in the formulas.
A parameter is of a particular type (column B). Distances should only have one parameter of the length type, for example. Depending on the type, the corresponding particular unit (Column D) can be selected.
You can enter the parameter value directly in Column C or define it using a formula in Column E. In addition to the general mathematical operations, the verification is possible using the If and Max/Min functions. The $\$$ reference can refer to a specific table. For example, $\$$1.1(A1) uses the value of the cell A1 of Table 1.1. In table column F, you can define a Range of Values to control the values of column C.
In addition to entering the parameters in the “Edit parameters” dialog box, it is also possible to import them using an Excel file.
The Formula Editor manages the equations of the parameterized input. You can open it by clicking the button in the table toolbar, the yellow or red corner in the table cell, or the function buttons next to the text box in the dialog boxes.
The formula can be entered in the “Formula” text box. It can include constant numerical values, parameters, or functions. The content of the other cells can be used in formulas via references. A reference starts with an exclamation mark and the reference cell is placed in brackets. For example, !(D2) is the value of the cell D2).
The cross-section shown in Figure 06 is to be entered parametrically in SHAPE-THIN 8.
For this, the parameters shown in Figure 07 are defined.
Then, node coordinates can be defined using formulas (see Figure 08).
The formulas used are shown in Figure 09.
In the next step, the element thickness is assigned using the corresponding parameter (Figure 10).
By changing the parameters, the dimensions of the cross‑section can now be easily adjusted (Figure 11).
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Knowledge Base Articles
In RFEM and RSTAB, it is possible to analyze members with a variable cross-section, which can also consist of freely defined SHAPE‑THIN cross-sections. For the determination of internal forces and deformations, the cross-section properties are interpolated.
Product Features Articles
Frequently Asked Questions (FAQ)
- I can't import the cross-section from the dxf file into the SHAPE-THIN program correctly, the cross-section is drawn to the wrong plane when importing. What can I do?
- In which drawing plane must a cross-section be drawn in the CAD application so that it can be imported into SHAPE-THIN via the dxf import?
- The installation of a Dlubal Software program is not possible due to the following message: "Program unsafe, protection by Microsoft Defender SmartScreen." How can I install the program?
- I get the following message when starting all installed Dlubal programs (also when running as administrator): "The application was unable to start correctly (0xc0150002)." What can I do?
- In SHAPE‑THIN, I get the error message saying that the material library cannot be opened. I have reinstalled the program and integrated the material library of another computer, but without any success. What should I do?
- The calculation of a file runs smoothly for my colleagues, but I get the message "Calculation stopped" for the same file. What should I do?
- When starting the Dlubal Software programs, the error message "Server is busy" appears. My colleagues do not experience this problem. I have already tried to reinstall. What should I do?
- What is the purpose of a fillet weld in SHAPE‑THIN?
- How can I display shear stresses on null elements in SHAPE‑THIN?
- How can I place a cross-section on another cross-section?