Compared to the RF‑/DYNAM Pro - Natural Vibrations add-on module (RFEM 5 / RSTAB 8), the following new features have been added to the Modal Analysis add-on for RFEM 6 / RSTAB 9:
Preset combination coefficients for various standards (EC 8, ASCE, and so on)
Optional neglect of masses (for example, mass of foundations)
Methods for determining the number of mode shapes (user-defined, automatic - to reach effective modal mass factors, automatic - to reach the maximum natural frequency)
Output of modal masses, effective modal masses, modal mass factors, and participation factors
Masses in mesh points displayed in tables and graphics
Various scaling options for mode shapes in the Result navigator
Automatic consideration of masses from self-weight
Direct import of masses from load cases or load combinations
Optional definition of additional masses (nodal, linear, or surface masses, as well as inertia masses) directly in the load cases
Optional neglect of masses (for example, mass of foundations)
Combination of masses in different load cases and load combinations
Preset combination coefficients for various standards (EC 8, SIA 261, ASCE 7,...)
Optional import of initial states (for example, to consider prestress and imperfection)
Structure Modification
Consideration of failed supports or members/surfaces/solids
Definition of several modal analyses (for example, to analyze different masses or stiffness modifications)
Selection of mass matrix type (diagonal matrix, consistent matrix, unit matrix), including user-defined specification of translational and rotational degrees of freedom
Methods for determining the number of mode shapes (user-defined, automatic - to reach effective modal mass factors, automatic - to reach the maximum natural frequency - only available in RSTAB)
Determination of mode shapes and masses in nodes or FE mesh points
Results of eigenvalue, angular frequency, natural frequency, and period
Output of modal masses, effective modal masses, modal mass factors, and participation factors
Masses in mesh points displayed in tables and graphics
Visualization and animation of mode shapes
Various scaling options for mode shapes
Documentation of numerical and graphical results in printout report
Wind loads are also not a problem in your design. You can automatically generate wind loads as member loads or area loads (RFEM) on the following structural components:
With Dlubal, you can safely and easily design structures all over the world. Select from a large number of standards in the Base Data. You can also decide whether to create the combinations automatically.
The following standards are available:
EN 1990
EN 1990 | Timber
EN 1990 | Road Bridges
EN 1990 | Cranes
EN 1990 | Geotechnical Engineering
EN 1990 | Base + Timber
EN 15512
ASCE 7
ASCE 7 | Timber
ACI 318
IBC
CAN/CSA
NBC
NBC | Timber
NBR 8681
IS 800
SIA 260
SIA 260 | Timber
BS 5950
GB 50009
GB 50068
GB 50011
CTE DB-SE
SANS 10160-1
NTC
NTC | Timber
AS/NZS 1170.0
SP 20.13330:2016
TSC | Steel
For the European standards (EC), the following National Annexes are available:
The Base Data dialog box includes a wide range of standards and the option to create combinations automatically. The following standards are available:
EN 1990:2002
EN 1990 + EN 1995:2004 (Timber)
EN 1990 + EN 1991-2; Road bridges
EN 1990 + EN 1991-3; Cranes
EN 1990 + EN 1997
to DIN 1055-100:2001-03
DIN 1055-100 + DIN 1052:2004-08 (timber)
DIN 1055-100 + DIN 18008 (Glass)
DIN 1052 (simplified) (timber)
DIN 18800:1990
ASCE 7‑10
ASCE 7-10 NDS (Wood)
ACI 318-14
IBC 2015
CAN/CSA S 16.1-94:1994
NBCC: 2005
NBR 8681
IS 800:2007
SIA 260:2003
SIA 260 + SIA 265:2003 (timber)
BS 5950-1:2000
GB 50009-2012
CTE DB-SE
For the European standards (EC), the following National Annexes are available:
First, it is necessary to decide whether to perform design according to ASD or LRFD. Then, you can enter the load cases, load combinations, and result combinations to be designed. Load combinations according to ASCE 7 can be generated either manually or automatically in RFEM/RSTAB.
In the next steps, you can adjust presettings of lateral intermediate supports, effective lengths, and other standard-specific design parameters, such as the modification factor Cb for lateral-torsional buckling or the shear lag factor. In the case of continuous members, it is possible to define individual support conditions and eccentricities of each intermediate node of single members. A special FEA tool determines critical loads and moments required for the stability analysis.
In connection with RFEM/RSTAB, it is possible to apply the Direct Analysis Method taking into account the influence of the general calculation according to the second-order analysis. In this way, you avoid using special enlargement factors.
First, it is necessary to decide whether to perform design according to ASD or LRFD. Then, you can enter the load cases, load combinations, and result combinations to be designed. Load combinations according to ASCE 7 can be generated either manually or automatically in RFEM/RSTAB.
Further specifications include presetting of lateral intermediate supports, effective lengths, and other standard-specific design parameters. When using continuous members, it is possible to define individual support conditions and eccentricities at each intermediate node of the single members. A special FEA tool then internally determines the effective radii of gyration required for the stability analysis for these situations.