Orthotropic surfaces are non-linear and cannot be designed in the RF‑STEEL Surfaces add-on module. It is possible to get a full stress analysis in RFEM for orthotropic surfaces defined with the orthotropy type "Constant Thickness" and compared to limiting stresses manually. For all other orthotropy types, the program is not aware of the geometric properties for the surface at every FE mesh point that are needed to calculate stresses. An extensive and detailed FE model would need to be created. See FAQ 2468 for an example of this. Surface types need to be set to "Standard" to be designed in the add-on module.
Warning for Orthotropic Surfaces in RF-STEEL Surfaces
When trying to calculate the design in RF‑STEEL Surfaces, I receive Warning No. 1162 – Surface No. XX is of the type "Orthotropic" and cannot be designed. What does this warning mean?
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The new generation of 3D FEA software is used for the structural analysis of members, surfaces, and solids.
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The Steel Design add-on performs the ultimate and serviceability limit state design checks of steel members according to various standards.
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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.
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The Torsional Warping (7 DOF) add-on allows you to consider cross-section warping as an additional degree of freedom.
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The Nonlinear Material Behavior add-on allows you to consider material nonlinearities in RFEM for example, isotropic plastic, orthotropic plastic, isotropic damage).
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The Structure Stability add-on performs stability analysis of structures. It determines critical load factors and the corresponding stability modes.
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The Construction Stages Analysis (CSA) add-on allows for considering the construction process of structures (member, surface, and solid structures) in RFEM.
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The Time-Dependent Analysis (TDA) add-on allows you to consider the time-dependent material behavior of members and surfaces. The long-term effects, such as creep, shrinkage, and aging, can influence the distribution of internal forces, depending on the structure.
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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.
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The Modal Analysis add-on allows for the calculation of eigenvalues, natural frequencies, and natural periods for member, surface, and solid models.
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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.
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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.
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The Stress-Strain Analysis add-on performs general stress analysis by calculating the existing stresses and comparing them with the limit stresses.
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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.
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The Steel Design add-on performs the ultimate and serviceability limit state design checks of steel members according to various standards.
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The Structure Stability add-on performs the stability analysis of structures. It determines critical load factors and the corresponding stability modes.
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The Stress-Strain Analysis add-on performs a general stress analysis by calculating the existing stresses and comparing them to the limit stresses.
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The Torsional Warping (7 DOF) add-on allows for considering cross-section warping as an additional degree of freedom when calculating members.
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The Modal Analysis add-on allows for the calculation of eigenvalues, natural frequencies, and natural periods for member, surface, and solid models.
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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.
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The Multilayer Surfaces add-on allows you to define multilayer surface structures. The calculation can be carried out with or without the shear coupling.
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The two-part Optimization & Costs / CO2 Emission Estimation add-on finds suitable parameters for parameterized models and blocks via the artificial intelligence (AI) technique of particle swarm optimization (PSO) for compliance with common optimization criteria. Furthermore, this add-on estimates the model costs or CO2 emissions by specifying unit costs or emissions per material definition for the structural model.
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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.
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The Timber Design add-on performs the ultimate, serviceability, and fire resistance limit state design checks of timber members according to various standards.
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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.
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The Aluminum Design add-on performs the ultimate and serviceability limit state design checks of aluminum members according to various standards.
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The two-part Optimization & Costs / CO2 Emission Estimation add-on finds suitable parameters for parameterized models and blocks via the artificial intelligence (AI) technique of particle swarm optimization (PSO) for compliance with common optimization criteria. Furthermore, this add-on estimates the model costs or CO2 emissions by specifying unit costs or emissions per material definition for the structural model.
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Concrete Design add-on allows for various design checks of members and columns according to international standards.
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The Timber Design add-on performs the ultimate, serviceability, and fire resistance limit state design checks of timber members according to various standards.
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The Aluminum Design add-on performs the ultimate and serviceability limit state design checks of aluminum members according to various standards.
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In RFEM, the Geotechnical Analysis add-on uses properties from soil samples to determine the soil body to be analyzed. The accurate determination of soil conditions significantly affects the quality of the structural analysis of buildings.