In RFEM 5 as well as RSTAB 8 in RF-/FOUNDATION Pro, you can save the foundation dimensions for all five foundation types as foundation templates in a user-defined database and use them later in other models.
In RF-/FOUNDATION Pro, the foundation design requires the definition of the corresponding loading (load cases, load combinations, or result combinations) for different design situations (STR, GEO, UPL, or EQU).
In RF‑/FOUNDATION Pro, reinforcement drawings are displayed after designing the foundation, where you can record all necessary structures of the reinforcement steel.
When modeling structural bearing systems, especially hall structures, some substructures of a foundation with no influence on the rising structure are not modeled in RFEM/RSTAB. In the case of hall structures, these are, for example, reinforced concrete floor slabs, strip foundations, and the ties between column foundations.
An elastic foundation can be applied to a member. Thus, the influence of the soil is usually included in the modeling. Member elastic foundations can only be defined for the "Beam" member type.
In RF‑/FOUNDATION Pro, the available reinforcing steel diameters can be adjusted by the user. The adjustment of the available rebar diameters works similarly to the same function in the RF‑/CONCRETE (Members) and RF‑/CONCRETE Columns add‑on modules.
In RFEM 5 and RSTAB 8, you can save problems and warnings occurring during the model check as an extra view. This way, you can easily work through the hints and messages, one after the other, cleaning the model. The function is available for double nodes, overlapping members/lines, and surfaces.
When calculating foundations according to EC 7 or EC 2, different foundation types or sizes are usually used in one object. However, boundary conditions like the soil parameters, the materials for foundations, concrete covers, and the load combinations selected for design remain the same for all foundations, as a rule.
You can use the elastic support option to avoid singularities due to a fixed nodal support in RFEM. This can be defined directly in the dialog box of the nodal support as a column in Z. It is necessary to take into account the geometry of the column, the material, and the support conditions. Here, we want to look at the option of modeling the column as a surface foundation.
In RF-/FOUNDATION Pro, a graphical display of the result details is available. To see them, go to Window 2.2 Governing Design Criteria after the calculation. In the interactive graphic of this window, individual design-relevant values can be displayed for each design performed.
If nonlinear effects - such as failing supports, foundations, member nonlinearities, or contact solids - are used in the model, you can deactivate them in the global calculation parameters.
In RF‑/FOUNDATION Pro, the reinforcement to be placed in the foundation slab and, if necessary, the bucket links, is displayed in a 3D rendering and in the reinforcement drawings.
In the RF-/FOUNDATION Pro add-on module, you can select the automatic dimensioning of the foundation plate geometry. In the dialog box for the design parameters of the foundation plate, you can, for example, specify the increment for the increase of the base area and the foundation plate thickness. You can also automatically increase the covering for a stabilizing effect of the geotechnical designs.
In RF-/FOUNDATION Pro, you can also calculate unreinforced foundation plates according to Section 12.9.3 of EN 1992-1-1 [1]. To do this, select the "Without bending reinforcement according to 12.9.3" check box in the "Foundation Plate" section of the "Details" dialog box.
An elastic foundation can be applied to a member. The foundation is used to include the influence of soil in the modeling. Member elastic foundations can only be defined for the "Beam" member type.
When modeling in RFEM, double lines may be created. To quickly find and delete them, if necessary, RFEM 5 allows you to export overlapping lines. This is possible, for example, in Excel or in a separate group of sections.
Generally, overlapping members in the model are not desired. To prevent RFEM from deleting an already defined member if another member is placed upon it, select "Allow Double Members" on the "Edit" menu.
RF‑/FOUNDATION Pro allows you to check the allowable eccentricity of the soil pressure resultants. According to DIN EN p;1997‑1/NA, this design is to be carried out with characteristic or representative loads.
For structural reasons, it may be necessary for a base plate not to be set centrically on a foundation. Therefore, an eccentric arrangement of the base plate is possible in RF‑/JOINTS Steel - Column Base by entering the parameters for the respective direction in Window 1.4.
The previous article, titled Lateral-Torsional Buckling in Timber Construction | Examples 1, explains the practical application for determining the critical bending moment Mcrit or the critical bending stress σcrit for a bending beam's lateral buckling using simple examples. In this article, the critical bending moment is determined by considering an elastic foundation resulting from a stiffening bracing.
When performing structural calculations, the derivation of forces from the roof to the foundations is one of the central tasks of the calculation, in addition to the dimensioning of the cross-sections.