This generation type creates a normal load case including imperfections. You can modify the load case manually.
In the load combinations, this load case can then be combined with the 'normal' load cases.
Do you have any questions?
Length: 00:01:33 min
Length: 00:01:00 min
Length: 00:00:00 min
Length: 00:01:22 min
Length: 00:00:00 min
Length: 00:02:00 min
Length: 00:00:00 min
Length: 00:00:00 min
_LI.jpg?mw=350&hash=a6debcf3b265d0612c870d5b232d173d9810dac1)
As an alternative to the equivalent member method, this article describes the possibility to determine the internal forces of a wall at risk of buckling according to the second-order analysis, taking imperfections into account, and to subsequently perform the cross-section design for bending and compression.
In this article, you will learn how to model and design cable structures in RFEM 6 or RSTAB 9.
This article describes and explains the influence of bending stiffness of cables on their internal forces. Furthermore, the text provides information on how this influence can be reduced.
The ASCE 7-22 Standard [1], Sect. 12.9.1.6 specifies when P-delta effects should be considered when running a modal response spectrum analysis for seismic design. In the NBC 2020 [2], Sent. 4.1.8.3.8.c gives only a short requirement that sway effects due to the interaction of gravity loads with the deformed structure should be considered. Therefore, there may be situations where second-order effects, also known as P-delta, must be considered when carrying out a seismic analysis.
The add-on module evaluates the pre-deformation of a load case as well as mode shapes of stability or dynamic analysis. Based on this initial deformation, it is possible either to pre-deform the structure or to create a load case with equivalent imperfections of members.
The pre-deformed initial model is useful especially for structures consisting of surface and solid elements (RFEM) as well as members. It is necessary to specify only the maximum value to which the deformation is to be scaled. All FE or model nodes will be scaled with regard to the initial deformation.
Equivalent imperfections are particularly useful for beam structures. You can define inclinations and precambers of members and sets of members in the additional window. They can be generated automatically, according to standards, or defined manually. The following standards are available:
-
EN 1992:2004 -
EN 1993:2005
-
DIN 18800:1990-11 -
DIN 1045-1:2001-07
-
DIN 1052:2004-08
Only the imperfection resulting from the initial deformation on the relevant member is applied. In addition, you can consider the reduction factors. This way, it is possible to apply the imperfection efficiently.
- Creation of a pre-deformed FE mesh in RFEM
- Generation of equivalent imperfections of members as equivalent loads, considering
- the reduction factors αu and αm (Eurocode)
- the precamber rises according to buckling stress curves
- Deformation of the structure due to nodal displacement
- Generation of imperfections in accordance with:
- the load case deformations
- the buckling shapes from RF-STABILITY/RSBUCK
- Equivalent imperfections on members and sets of members (for example, columns consisting of several members)
- Visualization of generated imperfection modes
This generation type creates a normal load case including imperfections. You can modify the load case manually.
In the load combinations, this load case can then be combined with the 'normal' load cases.
When generating a pre-deformed FE mesh in RFEM, the displacement data of each individual node are saved in the background. This can be used for the calculation of load combinations in RFEM. In order to check the generated data, the pre-deformation is displayed in tables and graphically.
If the nodes of the model are to be displaced, the node coordinates are modified directly after the generation. When generating equivalent imperfections, the module creates a normal load case, including member imperfections. To facilitate the data check, generated imperfections are displayed in result tables as well as graphically.
How can I create a drilled beam in RFEM?
I have calculated a pre-deformed structure according to the second-order analysis with RF‑STABILITY and RF‑IMP. Why are the deformations of the CO smaller than the applied pre-deformation?
How can I perform a buckling analysis for a surface in RFEM 5?
How can I perform a stability/buckling analysis on a plate structure?
I have to dimension a wall bracket as a steel brackets that I have modeled as surface components in RFEM 5. Which add-on module can I use to design it?
How do I reset the display settings to default?
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 | 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 Torsional Warping (7 DOF) add-on allows you to consider cross-section warping as an additional degree of freedom when calculating members.
Price of First License
1,480.00 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
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 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 | Design
Add-On
The Timber Design add-on performs the ultimate, serviceability, and fire resistance limit state design checks of timber members according to various standards.
Price of First License
1,930.00 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
RFEM 6 | Design
Add-On
The Aluminum Design add-on performs the ultimate and serviceability limit state design checks of aluminum members according to various standards.
Price of First License
1,750.00 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
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 | 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 | 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 | 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 | Design
Add-On
Concrete Design add-on allows for various design checks of members and columns according to international standards.
Price of First License
2,550.00 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 | Design
Add-On
The Timber Design add-on performs the ultimate, serviceability, and fire resistance limit state design checks of timber members according to various standards.
Price of First License
1,930.00 USD
RSTAB 9 | Design
Add-On
The Aluminum Design add-on performs the ultimate and serviceability limit state design checks of aluminum members according to various standards.
Price of First License
1,750.00 USD