.svg?mw=64&hash=343d71fbdf234f1411db2920f2dff33c0dbd6231)
Question:
Is it possible to model a slab made of trapezoidal sheet metals?
Answer:
There are two options to do this:
1. Modeling as a folded plate structure (see Image 01)
2. Modeling as an orthotropic surface (see Image 02 and Image 03)
The first option is only useful if the stresses in the trapezoidal sheeting are of interest. The individual corrugation is to be modeled using surfaces. The modeling and calculation effort is very high. You can facilitate the modeling slightly: The cross-section library of RFEM contains all common trapezoidal sections. Create a member with a trapezoidal cross-section. Then, generate surfaces from the member using the corresponding shortcut menu option. You can then modify or copy the created surfaces with trapezoidal sheeting.
If the stiffness of the trapezoidal sheeting is only relevant to the analysis, modeling as an orthotropic surface is reasonable. When defining the surface, select the "Orthotropic" stiffness type. Click the [Edit Parameters] button next to the list box to define the orthotropic properties. The stiffnesses can be described by equivalent thicknesses or directly by the coefficients of the stiffness matrix (see the manual). For the orthotropy direction, you can specify any angle that is related to the local surface axis system. This angle can also be controlled graphically (Display-Navigator "Model → Surfaces → Orthotropy Directions").
Model Used in
Trapezoidal Sheeting
| Number of Nodes | 62 |
| Number of Lines | 85 |
| Number of Members | 2 |
| Number of Surfaces | 27 |
| Total Weight | 0.113 tons |
| Dimensions (Metric) | 5.000 x 1.500 x 0.035 m |
| Dimensions (Imperial) | 16.4 x 4.92 x 0.11 feet |
| Program Version | 5.23.01 |
You can download this structural model to use it for training purposes or for your projects. However, we do not assume any guarantee or liability for the accuracy or completeness of the model.
Length: 00:00:06 min
Knowledge Base
Length: 00:00:34 min
Length: 00:03:54 min
Length: 00:00:59 min
Knowledge Base
Length: 00:00:00 min
Length: 00:01:10 min
Length: 00:00:16 min
Length: 01:05:29 min
.png?mw=350&hash=b023d6c658e181cb7d69028c0f3994dedab96fc5)
In RFEM 5 and RSTAB 8, it is possible to assign nonlinearities to member hinges. In addition to the nonlinearities "Fixed if" and "Partial activity", you can select "Diagram". If you select the "Diagram" option, you have to specify the according settings for the activity of the member hinge. For the individual definition points, it is necessary to specify the abscissa and ordinate values (deformations or rotations and the according internal forces) that define the hinge.
Designing rigid end plate connections is difficult for four-row connection geometries and multi-axis bending stresses, because there are no official design methods.
The elastic deformations of a structural component due to a load are based on Hooke's law, which describes a linear stress-strain relation. They are reversible: After the relief, the component returns to its original shape. However, plastic deformations lead to irreversible deformations. The plastic strains are usually considerably larger than the elastic deformations. For plastic stresses of ductile materials such as steel, yielding effects occur where the increase in deformation is accompanied by hardening. They lead to permanent deformations - and in extreme cases to the destruction of the structural component.
The definition of the non-linear contact problem plays an important role for more detailed investigations of shear/hole bearing connections or their immediate environment. This article uses a solid model to search for comparable and simplified surface models.
- Numerous component types, such as base and end plates, web angles, fin plates, gusset plates, stiffeners, tapers, or ribs for easy input of typical connection situations
- Universally applicable basic components (such as plates, welds, bolts, auxiliary planes) for modeling complex connection situations
- Graphical display of the connection geometry with dynamic updating during the input
- Wide range of cross-section shapes: I-sections, U-sections, angles, T-sections, hollow sections, built-up cross-sections and thin-walled sections
- Library in the Dlubal Center with a large number of program-side template connections, including user-defined templates
- Automatic adaptation of the connection geometry based on the relative arrangement of the components to each other – even in case of subsequent editing of the structural components
In the ultimate configuration of the steel joint design, you have the option to modify the limit plastic strain for welds.
The "Base Plate" component allows you to design base plate connections with cast-in anchors. In this case, plates, welds, anchorages, and steel-concrete interaction are analyzed.
In the "Edit Section" dialog box, you can display the buckling shapes of the Finite Strip Method (FSM) as a 3D graphic.
Are the models and presentations from Info Day 2018 freely available, and can you send them to me?
How can I additionally model welds for the connection of two surfaces with a contact solid?
I would like to use surface releases to model a bolt connection that can only absorb compressive stresses from the support. Unfortunately, I cannot do this because my model is always unstable. Is there a template model?
After importing an .stp file, my model is unstable. What can be the reason?
Are the models and presentations from Info Day 2017 freely available, and can you send them to me?
Is it also possible to use nonlinear material behavior in a time history analysis?
.jpg?mw=350&hash=91f398b559b26a6ac36fd7ecdf5e395e7b9b856d)
Recommended Products for You
RFEM 6 | Main Program RFEM 6
Main Program
The new generation of 3D FEA software is used for the structural analysis of members, surfaces, and solids.
Price of First License
4,170.00 USD
RFEM 6 | Design
Add-On
The Steel Design add-on performs the ultimate and serviceability limit state design checks of steel members according to various standards.
Price of First License
2,550.00 USD
RFEM 6 | Joints
.png?mw=600&hash=49b6a289915d28aa461360f7308b092631b1446e)
Add-On
The Steel Joints add-on for RFEM allows you to analyze steel connections using an FE model. The FE model is generated automatically in the background and can be controlled via the simple and familiar input of components.
Price of First License
2,110.00 USD
RFEM 6 | Additional Analysis
Add-On
The Torsional Warping (7 DOF) add-on allows you to consider cross-section warping as an additional degree of freedom.
Price of First License
1,480.00 USD
RFEM 6 | Additional Analysis
Add-On
The Nonlinear Material Behavior add-on allows you to consider material nonlinearities in RFEM for example, isotropic plastic, orthotropic plastic, isotropic damage).
Price of First License
1,480.00 USD
RFEM 6 | Additional Analysis
Add-On
The Structure Stability add-on performs stability analysis of structures. It determines critical load factors and the corresponding stability modes.
Price of First License
1,300.00 USD
RFEM 6 | Additional Analysis
Add-On
The Construction Stages Analysis (CSA) add-on allows for considering the construction process of structures (member, surface, and solid structures) in RFEM.
Price of First License
1,570.00 USD
RFEM 6 | Additional Analysis
Add-On
The Time-Dependent Analysis (TDA) add-on allows you to consider the time-dependent material behavior of members. The long-term effects, such as creep, shrinkage, and aging, can influence the distribution of internal forces, depending on the structure.
Price of First License
1,030.00 USD
RFEM 6 | Additional Analysis
Add-On
The Form-Finding add-on finds the optimal shape of members subjected to axial forces and tension-loaded surface models. The shape is determined by the equilibrium between the member axial force or the membrane stress and the existing boundary conditions.
Price of First License
2,060.00 USD
RFEM 6 | Dynamic Analysis
Add-On
The Modal Analysis add-on allows for the calculation of eigenvalues, natural frequencies, and natural periods for member, surface, and solid models.
Price of First License
1,210.00 USD
RFEM 6 | Dynamic Analysis
Add-On
Using the Pushover Analysis add-on, you can analyze the seismic actions on a particular building, and thus assess whether the building can withstand an earthquake.
Price of First License
1,300.00 USD
RFEM 6 | Special Solutions
Add-On
The Building Model add-on for RFEM allows you to define and manipulate a building using stories. The stories can be adjusted in many ways afterwards. The information about stories and the entire model (center of gravity) is displayed in tables and graphics.
Price of First License
1,660.00 USD
RFEM 6 | Design
Add-On
The Stress-Strain Analysis add-on performs general stress analysis by calculating the existing stresses and comparing them with the limit stresses.
Price of First License
1,210.00 USD
RSTAB 9 | Main Program RSTAB 9
Main Program
The modern 3D structural analysis and design program is suitable for the structural and dynamic analysis of beam structures as well as the design of concrete, steel, timber, and other materials.
Price of First License
2,910.00 USD
RSTAB 9 | Design
Add-On
The Steel Design add-on performs the ultimate and serviceability limit state design checks of steel members according to various standards.
Price of First License
2,550.00 USD
RSTAB 9 | Additional Analysis
Add-On
The Structure Stability add-on performs the stability analysis of structures. It determines critical load factors and the corresponding stability modes.
Price of First License
1,300.00 USD
RSTAB 9 | Design
Add-On
The Stress-Strain Analysis add-on performs a general stress analysis by calculating the existing stresses and comparing them to the limit stresses.
Price of First License
1,120.00 USD
RSTAB 9 | Additional Analysis
Add-On
The Torsional Warping (7 DOF) add-on allows for considering cross-section warping as an additional degree of freedom when calculating members.
Price of First License
1,480.00 USD
RSTAB 9 | Dynamic Analysis
Add-On
The Modal Analysis add-on allows for the calculation of eigenvalues, natural frequencies, and natural periods for member, surface, and solid models.
Price of First License
1,210.00 USD
RSTAB 9 | Dynamic Analysis
Add-On
Earthquakes may have a significant impact on the deformation behavior of buildings. A pushover analysis allows you to analyze the deformation behavior of buildings and compare them with seismic actions. Using the Pushover Analysis add-on, you can analyze the seismic actions on a particular building, and thus assess whether the building can withstand the earthquake.
Price of First License
1,300.00 USD
RFEM 6 | Design
Add-On
The Concrete Design add-on allows for various design checks according to international standards. You can design members, surfaces, and columns, as well as perform punching and deformation analyses.
Price of First License
2,550.00 USD
RFEM 6 | Design
Add-On
The Masonry Design add-on for RFEM allows you to design masonry using the finite element method. It was developed as part of the research project titled DDMaS – Digitizing the Design of Masonry Structures. The material model represents the nonlinear behavior of the brick-mortar combination in the form of macro-modeling.
Price of First License
1,660.00 USD