### GENERAL PURPOSE MODULES

### 7DOF MODULE -BEAM ELEMENT WITH 7 DEGREES OF FREEDOM

This module provides the option to define beams with 7 degrees of freedom. The additional, 7th DOF represents the warping of the cross-section.

A circular cross-section of a bar, or a circular hollow section will remain in-plane as a result of uniform twisting, however, all other section types will experience warping of the cross-section.

Warping occurs when the twisting of a member results in the cross-sections distorting out-of-plane along the direction of the members longitudinal axis. If the out-of-plane distortion is restrained or prevented, longitudinal stresses and strains develop in the member. Warping can be constrained by a support or concentrated torque.

Constrained warping can significantly affect the stress distribution in thin-walled beams and columns, which should be considered in the design. Warping is also important if the members of the structure are sensitive to lateral-torsional buckling.

#### VIDEO

#### 7DOF MODULE

Experience the -7th degree of- freedom in AxisVM. With the new 7DOF module, beams with 7 degrees of freedom can be defined. The 7th degree of freedom represents the warping of the cross-section. Consideration of the warping effect is important in cases where the members are sensitive to lateral-torsional buckling - especially steel members

### IMP MODULE – GEOMETRIC IMPERFECTIONS BASED ON BUCKLING SHAPES

Structural analysis is usually performed on an idealized, geometrically perfect model. However, nothing is perfect in the real world. The structural geometry, the material behaviour and the position of the loads are all imperfect. Geometrically and materially nonlinear analysis with imperfections included (GMNIA) may be used effectively instead of linear methods for strength and stability verification of structures, structural elements and details. This is especially true in the case of complex structural details and parts where the stability and load-bearing capacity can be hardly verified with simpler methods.

The IMP module of AxisVM allows users to account for such geometric imperfections, which can be created by scaling and then superimposing the buckling-mode shapes. The effect of imperfections can be taken into account via a geometrically nonlinear analysis on a load combination, which includes imperfection-type load cases.

Requirements: NL or PNL (e.g. NL1S, PNL3P) configuration is required to account for geometric imperfections based on buckling mode shapes

#### DESIGN CODES

#### CHARACTERISTICS

➡ scaling and superimposing of buckling mode shapes

➡ displaying of created imperfect geometries

➡ including imperfection-type load cases in load combinations

➡ performing nonlinear analysis on models with geometric imperfections

#### DETAILS

#### CREATING EQUIVALENT GEOMETRIC IMPERFECTIONS

The imperfect geometry can be compiled from the mode-shapes obtained from a buckling analysis, even corresponding to multiple load cases. Displacement components and the respective maximum values for each buckling mode shape can be specified. The created geometric imperfections can be included in load combinations.

#### NONLINEAR ANLYSIS OF MODELS WITH EQUIVALENT GEOMETRIC IMPERFECTIONS

Internal forces may be obtained on models with geometric imperfection via a geometrically nonlinear analysis include large-displacement effects. The loss of stability mode can be determined with a displacement-controlled nonlinear analysis. Finite element simulation-based design is also possible by using nonlinear material models and geometric imperfections together.

#### VIDEO -IMP MODULE

The IMP module of AxisVM allows users to account for such geometric imperfections, which can be created by scaling and then superimposing the buckling-mode shapes. The effect of imperfections can be taken into account via a geometrically nonlinear analysis on a load combination, which includes imperfection-type load cases.

### CFD MODULE – COMPUTATIONAL FLUID DYNAMICS INTERFACE

Design codes/standards provide guidance for the inclusion of wind pressure factors only for structures with close to regular geometry. In the case of more complex or compound structures, these methods are not applicable, and the pressure coefficients must be determined individually by a fluid dynamics simulation (CFD modeling) or a wind tunnel test. The CFD module allows for importing these results into AxisVM.

The CFD module is a generic interface which enables defining pressures caused by flowing substances over domains or load panels.

Requirements: the module is an option in the basic packages (analysis options), which is recommended when designing structures with loadings from flowing substances

#### DESIGN CODES

#### CHARACTERISTICS

➡ it is recommended for structures with irregular geometry or with loads not covered by design codes/standards

➡ currently it can only apply static pressure loads (constant functions of time)

➡ it interpolates pressure values from CFD simulations on the contour of the surface elements of the structure

➡ it is sufficient to specify the spatial coordinates of the measurements and the corresponding pressure values, from which the program determines the surface load values perpendicular to the surfaces

#### DETAILS

#### DETERMINATION OF PRESSURE DISTRIBUTION

The pressure distribution on the surface of the structure can be obtained from a CFD model or a wind tunnel experiment.

#### IMPORT OF PRESSURE DISTRIBUTION USING THE CFD MODULE

The CFD interface is available from the Loads panel, assuming that a static loadcase has been selected.

#### RESULTS VISUALIZATION

Deformations and forces generated by the applied wind pressure distribution can be displayed in the usual ways such as in diagrams, isolines, or isosurfaces.

#### VIDEO -CFD MODULE

Design codes/standards provide guidance for the inclusion of wind pressure factors only for structures with close to regular geometry. In the case of more complex or compound structures, these methods are not applicable, and the pressure coefficients must be determined individually by a fluid dynamics simulation (CFD modeling) or a wind tunnel test. The CFD module allows for importing these results into AxisVM. The CFD module is a generic interface which enables defining pressures caused by flowing substances over domains or load panels.