The "2D | Story" calculation diagram type is used to create result diagrams via the building axis. This allows you to easily analyze the behavior of the entire building under static and dynamic effects.
You can use this diagram type, for example, to visualize the seismic force over the building height.
You can simulate the static friction effects between two supporting components along a line using the "Friction" nonlinearity in the Line Release Type.
Use the "Import Support Reactions" Load Wizard in RFEM 6 and RSTAB 9 to easily transfer reaction forces from other models. The wizard allows you to connect all or several nodal and line loads of different models with each other in a few steps.
The load transfer from load cases and load combinations can be carried out automatically or manually. It's necessary that the models are saved in the same Dlubal Center project.
The "Import Support Reactions" load wizard supports the concept of positional statics and allows you to digitally connect the individual positions.
During the calculation, the selected horizontal load is increased in load steps. A static nonlinear analysis is carried out for each load step until reaching the specified limit condition.
The results of the pushover analysis are extensive. On one hand, the structure is analyzed for its deformation behavior. This can be represented by a force-deformation line of the system (a capacity curve). On the other hand, the response spectrum effect can be displayed in the ADRS display (Acceleration-Displacement Response Spectrum). The target displacement is automatically determined in the program based on these two results. The process can be evaluated graphically and in tables.
The individual acceptance criteria can then be graphically evaluated and assessed (for the next load step of the target displacement, but also for all other load steps). The results of the static analysis are also available for the individual load steps.
This function provides you with the option to adopt reaction forces from other models as nodal and line loads.
The option not only transfers the reaction load as an action, but digitally couples the support load of the original model with the load size of the target object. The subsequent changes in the original model are automatically adopted in the target model.
This technology supports the concept of positional statics and allows you to digitally connect the individual positions of the same Dlubal Center project.
Do you want to consider other loads as masses in addition to the static loads? The program allows that for nodal, member, line and surface loads. For this, you need to select the Mass load type when defining the load of interest. Define a mass or mass components in the X, Y, and Z directions for such loads. For nodal masses, you have an additional option to also specify moments of inertia X, Y, and Z in order to model more complex mass points.
You can already see it in the image: Imperfections can also be taken into account when defining a modal analysis load case. The imperfection types that you can use in the modal analysis are notional loads from load case, initial sway via table, static deformation, buckling mode, dynamic mode shape, and group of imperfection cases.
By solving the numerical flow problem, you can obtain the following results on and around the model:
Pressure on structure surface
Coefficient Cp distribution on the structure surfaces
Pressure field about the structure geometry
Velocity field about the structure geometry
Turbulence k-ω field about the structure geometry
Turbulence k-ε field about the structure geometry
Velocity vectors about the structure geometry
Streamlines about the structure geometry
Forces on member-shaped structures that were originally generated from member elements
Convergence diagram
Direction and size of the flow resistance of the defined structures
Despite this amount of information, RWIND 2 remains clearly arranged, as is typical for the Dlubal programs. You can specify freely definable zones for a graphic evaluation. Voluminously displayed flow results about the structure geometry are often confusing – you know the problem for sure. That's why RWIND Basic provides freely movable section planes for the separate display of the "solid results" in a plane. For the 3D branched streamline result, you have an option to select between a static and an animated display in the form of moving line segments or particles. This option helps you to represent the wind flow as a dynamic effect.
You can export all results as a picture or, especially for the animated results, as a video.
The organization of imperfections is efficiently solved by imperfection cases. The cases allow you to describe an imperfection from local imperfections, equivalent loads, initial sway via table (new), a static deformation, a buckling mode, a dynamic mode shape, or a combination of all these types (new).
Did you know that Equivalent static loads are generated separately for each relevant eigenvalue and excitation direction. These loads are saved in a load case of the Response Spectrum Analysis type and RFEM/RSTAB performs a linear static analysis.
The standards already specify the approximation methods (for example, deformation calculation according to EN 1992‑1‑1, 7.4.3, or ACI 318‑19, 24.3.2.5) that you need for your deformation calculation. In this case, the so-called effective stiffnesses are calculated in the finite elements in accordance with the existing limit state with / without cracks. You can then use these effective stiffnesses to determine the deformations by means of another FEM calculation.
Consider a reinforced concrete cross-section for the calculation of the effective stiffnesses of the finite elements. Based on the internal forces determined for the serviceability limit state in RFEM, you can classify the reinforced concrete cross-section as "cracked" or "uncracked". Do you consider the effect of the concrete between the cracks? In this case, this is done by means of a distribution coefficient (for example, according to EN 1992‑1‑1, Eq. 7.19, or ACI 318‑19, 24.3.2.5). You can assume the material behavior for the concrete to be linear-elastic in the compression and tension zone until reaching the concrete tensile strength. This procedure is sufficiently precise for the serviceability limit state.
When determining the effective stiffnesses, you can take into accout the creep and shrinkage at the "cross-section level." You don't need to consider the influence of shrinkage and creep in statically indeterminate systems in this approximation method (for example, tensile forces from shrinkage strain in systems restrained on all sides are not determined and have to be considered separately). In summary, the deformation calculation is carried out in two steps:
Calculation of effective stiffnesses of the reinforced concrete cross-section assuming linear-elastic conditions
Calculation of the deformation using the effective stiffnesses with FEM
Consideration of 7 local deformation directions (ux, uy, uz, φx, φy, φz, ω) or 8 internal forces (N, Vu, Vv, Mt,pri, Mt,sec, Mu, Mv, Mω) when calculating member elements
Usable in combination with a structural analysis according to linear static, second-order, and large deformation analysis (imperfections can also be taken into account)
In combination with the Stability Analysis add-on, allows you to determine critical load factors and mode shapes of stability problems such as torsional buckling and lateral-torsional buckling
Consideration of end plates and transverse stiffeners as warping springs when calculating I-sections with automatic determination and graphical display of the warping spring stiffness
Graphical display of the cross-section warping of members in the deformation
RFEM 6 offers you a wide range of helpful and efficient functions for working with load combinations. You can add the load cases included in load combinations together and then calculate them in consideration of the corresponding factors (partial safety and combination factors, coefficients regarding consequence classes, and so on). Generate the load combinations automatically in compliance with the combination expressions of the standard. You can perform the calculation according to the linear static analysis, second-order analysis, or large deformation analysis, as well as for post-critical analysis. Optionally, you can define whether the internal forces should be related to the deformed or non-deformed structure.
Select the individually suitable calculation parameters for your project: You can perform the calculation for all member types according to the linear static, second-order, or large deformation analysis. You have this selection option for load cases and load combinations. You can specifically set further calculation parameters for load cases, load combinations, and result combinations, which ensures a high degree of flexibility with regard to the calculation method and detailed specifications.
If you are working with nonlinearities, this feature is suited very well to support you. For example, you can specify nonlinearities of member end releases (yielding, tearing, slippage, and so on) and supports (including friction). Furthermore, you can use special dialog boxes to determine the spring stiffnesses of columns and walls based on the geometry specifications.
Always keep an eye on your results. In addition to the resulting load cases in RFEM or RSTAB (see below), the results from the aerodynamics analysis in RWIND 2 represent the flow problem as a whole:
Pressure on structure surface
Pressure field about structure geometry
Velocity field about structure geometry
Velocity vectors about structure geometry
Flow lines about structure geometry
Forces on member-shaped structures that were originally generated from member elements
Convergence diagram
Direction and size of the flow resistance of the defined structures
These results are displayed in the RWIND 2 environment and evaluated graphically. The flow results around the structure geometry in the overall display are rather confusing, but the program has a solution for this. In order to present clearly arranged results, freely movable section planes are displayed for the separate display of the 'solid results' in a plane. Accordingly, for the 3D branched streamline result, the program presents you an animated display in the form of moving lines or particles in addition to the static one. This option helps to represent the wind flow as a dynamic effect. You can export all results as a picture or, especially for the animated results, as a video.
With this function, it is possible to refine the FE mesh on surfaces automatically. The mesh refinement is gradual. In each step, the FE mesh is recreated based on an error comparison of the results in the previous calculation step. The numerical error is evaluated from the results of surface elements and is based on the energy formulation of Zienkiewicz-Zhu.
The error evaluation is carried out for a linear static analysis. We select a load case (or load combination) for which the FE mesh is generated. The FE mesh is then used for all calculations.
RF-/DYNAM Pro - Nonlinear Time History is integrated in the structure of RF‑/DYNAM Pro - Forced Vibrations and extended by two nonlinear analysis methods (one nonlinear analysis in RSTAB).
Force-time diagrams can be entered as transient, periodic, or as a function of time. Dynamic load cases combine the time diagrams with the static load cases, which provides high flexibility. Furthermore, it is possible to define time steps for the calculation, structural damping, and export options in the dynamic load cases.
Full integration in RFEM/RSTAB with import of geometry and load case data
Automatic selection of members for design according to specified criteria (e.g. only vertical members)
In connection with the extension EC2 for RFEM/RSTAB, you can perform the design of reinforced concrete compression elements according to the method based on nominal curvature in compliance with EN 1992 -1‑1:2004 (Eurocode 2) and the following National Annexes:
DIN EN 1992-1-1/NA/A1:2015-12 (Germany)
ÖNORM B 1992-1-1:2018-01 (Austria)
Belgium NBN EN 1992-1-1 ANB:2010 for design at normal temperature, and NBN EN 1992-1-2 ANB:2010 for fire resistance design (Belgium)
BDS EN 1992-1-1:2005/NA:2011 (Bulgaria)
EN 1992-1-1 DK NA:2013 (Denmark)
NF EN 1992-1-1/NA:2016-03 (France)
SFS EN 1992-1-1/NA:2007-10 (Finland)
UNI EN 1992-1-1/NA:2007-07 (Italy)
LVS EN 1992-1-1:2005/NA:2014 (Latvia)
LST EN 1992-1-1:2005/NA:2011 (Lithuania)
MS EN 1992-1-1:2010 (Malaysia)
NEN-EN 1992-1-1+C2:2011/NB:2016 (Netherlands)
NS EN 1992-1 -1:2004-NA:2008 (Norway)
PN EN 1992-1-1/NA:2010 (Poland)
NP EN 1992-1-1/NA:2010-02 (Portugal)
SR EN 1992-1-1:2004/NA:2008 (Romania)
SS EN 1992-1-1/NA:2008 (Sweden)
SS EN 1992-1-1/NA:2008-06 (Singapore)
STN EN 1992-1-1/NA:2008-06 (Slovakia)
SIST EN 1992-1-1:2005/A101:2006 (Slovenia)
UNE EN 1992-1-1/NA:2013 (Spain)
CSN EN 1992-1-1/NA:2016-05 (Czech Republic)
BS EN 1992-1-1:2004/NA:2005 (United Kingdom)
TKP EN 1992-1-1:2009 (Belarus)
CYS EN 1992-1-1:2004/NA:2009 (Cyprus)
In addition to the National Annexes (NA) listed above, you can define a specific NA, applying user-defined limit values and parameters.
Optional consideration of creep
Diagram-based determination of buckling lengths and slenderness from the restraint ratios of columns
Automatic determination of ordinary and unintentional eccentricity from additionally available eccentricity according to the second-order analysis
Design of monolithic structures and precast elements
Analysis with regard to the standard reinforced concrete design
Determination of internal forces according to the linear static analysis and the second-order analysis
Analysis of governing design locations along the column due to existing loading
Output of required longitudinal and stirrup reinforcement
Fire resistance design according to the simplified method (zone method) according to EN 1992-1-2 allowing the fire resistance design of brackets.
Fire resistance design with optional longitudinal reinforcement design according to DIN 4102-22:2004 or DIN 4102-4:2004, Table 31
Longitudinal and link reinforcement proposal with graphic display in 3D rendering
Summary of design ratios, including all design details
Graphical representation of relevant design details in RFEM/RSTAB work window
The nonlinear calculation adopts the real mesh geometry of planar, buckled, simple curved, or double curved surface components from the selected cutting pattern and flattens this surface component in compliance with the minimization of distortion energy, assuming defined material behavior.
In simplified terms, this method attempts to compress the mesh geometry in a press, assuming frictionless contact, and to find the state in which the stresses from flattening in the component are in equilibrium in the plane. This way, minimum energy and optimum accuracy of the cutting pattern are achieved. Compensation for warp and weft as well as compensation for boundary lines are considered. Then, the defined allowances on boundary lines are applied to the resulting planar surface geometry.
Features:
Minimization of distortion energy in the flattening process for very accurate cutting patterns
Application for almost all mesh arrangements
Recognition of adjacent cutting pattern definitions to keep the same length
The deformation analysis according to the approximation method defined in standards (for example, deformation analysis according to EN 1992‑1‑1, 7.4.3) applies to the calculation of "effective stiffnesses" in the finite elements in accordance with the existing limit state of the concrete with or without cracks. These stiffnesses are used to determine the surface deformation by repeated FEM calculation.
The effective stiffness calculation of finite elements takes into account a reinforced concrete cross-section. Based on the internal forces determined for the serviceability limit state in RFEM, the program classifies the reinforced concrete cross-section as 'cracked' or 'uncracked'. If the tension stiffening at a section should be considered as well, a distribution coefficient (according to EN 1992-1-1, Eq. 7.19, for example) is used. The material behavior for the concrete is assumed to be linear-elastic in the compression and tension zone until the concrete tensile strength is reached. This is reached exactly in the serviceability limit state.
When determining the effective stiffnesses, creep and shrinkage are taken into account at the "cross-section level". The influence of shrinkage and creep in statically indeterminate systems is not taken into account in this approximation method (for example, tensile forces from shrinkage strain in systems restrained on all sides are not determined and must be considered separately). In summary, RF-CONCRETE Deflect calculates deformations in two steps:
Calculation of effective stiffnesses of the reinforced concrete cross-section assuming linear-elastic conditions
Calculation of the deformation using the effective stiffnesses with FEM
The calculation can be performed for all member types according to the linear static, second-order, or large deformation analysis. This selection option is available for load cases and load combinations. Additional calculation parameters are individually adjustable for load cases, load combinations, and result combinations. This ensures a high degree of flexibility with regard to the calculation method and detailed specifications.
It is possible to specify nonlinearities of member end releases (yielding, tearing, slippage, and so on) and supports (including friction). There are special dialog boxes available for determining the spring stiffnesses of columns and walls based on the geometry specifications.
Equivalent static loads are generated separately for each relevant eigenvalue and excitation direction. They are exported to static load cases to perform the linear static analysis in RFEM/RSTAB.
In order to check the overall model graphically, you can use the viewer function. Statically effective equipment can be generated with a single mouse click and exported to RFEM/RSTAB.
All module data are included in the global RFEM/RSTAB printout report.