100 Results
View Results:
Sort by:
The new RF‑/DYNAM Pro - Natural Vibrations module has been available since RFEM version 5.04.xx and RSTAB version 8.04.xx were released. Masses can now be imported directly from load cases and load combinations.
Not only do RF-/STEEL EC3 and RF-/TIMBER Pro perform cross-section designs and stability analyses, they allow you to perform serviceability limit state designs. For this, it is possible to relate the deformation to the undeformed initial system or to shifted members ends.
In order to represent the stiffness of the entire structure correctly, you can consider shear coupling between the ceiling and the downstand beam using the line release. This way, you can define a spring constant, thus avoiding the replacement system by using coupling members. The spring constant results from the shift modulus of the fastener, which can be determined according to EN 1995-1-1 or ANSI/AWC NDS, for example.
RF‑/FOUNDATION Pro introduced the geotechnical design of single foundations according to EN 1997‑1 in RFEM 5 and RSTAB 8. Depending on the National Annex preset in the add‑on module, you can determine the bearing resistance using Approach 2 or 3 in compliance with EN 1997‑1 up to Version x.04.0108.
In RF‑/TIMBER Pro, it is also possible to define the effective length for lateral-torsional buckling. The effective length for lateral-torsional buckling is then calculated according to EN 1995‑1‑1, Table 6.1. This option is useful especially for non-uniform load introduction.
As of the program version X.06 of the RF‑/TIMBER Pro, RF‑/TIMBER AWC, and RF‑/TIMBER CSA add‑on modules, notches and cross‑section reductions can be considered in the design. The procedure is as follows:
Various optimizations are available with program version x.06.1103. The RF-/FOUNDATION Pro add-on module has also been subjected to further development.
For the ultimate limit state design, EN 1998-1 Section 2.2.2 and 4.4.2.2 [1] requires the calculation considering the second-order theory (P-Δ effect). This effect may be neglected only if the interstory drift sensitivity coefficient θ is less than 0.1.
As of program version x.06.1103, you can enter a soil profile in RF‑/FOUNDATION Pro. This gives you the advantage of setting several soil layers with different soil parameters above and below the foundation base. To enter the soil layers, there is a library with various soil types that can also be extended with user‑defined soils. The user-defined soil profile is shown in an interactive information graphic. Any change (for example, a soil thickness modification) is reflected in the graphic immediately.
Long-span glued-laminated beams are usually supported by a reinforced concrete column with torsional restraints.
According to DIN EN 1990/NA:2010‑12 – NDP to A.1.2.1(1) Comment 2, it is necessary to apply only one of the two climatic actions in the combination expressions for actions according to 6.4.3 and 6.5.3 in the case of places located up to +1,000 m above mean sea level if snow and wind are available as collateral actions, in addition to non‑climatic leading action.
In the case of tension connections with cleats subjected to unilateral loading, the external members (side timber) are loaded by an additional bending moment due to the eccentric load distribution. However, this fact is not mentioned in EN 1995‑1‑1 and is considered in the National Annex to DIN EN 1995‑1‑1 by the reduction of the tensile strength. This reduction depends on the pull-off strength of the fasteners.
At first glance, the material list for masonry seems empty. The reason for this is that bricks and mortar can be used in many combinations, which would lead to a very long and unclear list. Therefore, it is necessary first to create a new material for masonry in order to consider these possible combinations in the calculation.
According to DIN EN 1990/NA:2010‑12 - NDP to A.1.2.1(1) Comment 2, it is possible to neglect the combination of snow as a collateral action in cases of wind/snow combination with wind as the leading action in wind zones III and IV.
For the serviceability limit state design according to Section 6.6 of Eurocode EN 1997‑1, settlement has to be calculated for spread foundations. RF-/FOUNDATION Pro allows you to perform the settlement calculation for a single foundation. For this, you can chose between an elastic and a solid foundation. By defining a soil profile, it is possible to consider several soil layers under the foundation base. The results of the settlement, foundation tilting, and vertical soil contact stress distribution are displayed graphically and in tables to provide a quick and clear overview of the calculation performed. In addition to the design of the foundation settlement in RF-/FOUNDATION Pro, the structural analysis determines the representative spring constants for the support and can be exported to the structural model of RFEM or RSTAB.
Basically, you can design the structural components made of cross-laminated timber in the RF-LAMINATE add-on module. Since the design is a pure elastic stress analysis, it is necessary to additionally consider the stability issues (flexural buckling and lateral-torsional buckling).
The following article describes a design using the equivalent member method according to [1] Section 6.3.2, performed on an example of a cross-laminated timber wall susceptible to buckling described in Part 1 of this article series. The buckling analysis will be performed as a compressive stress analysis with reduced compressive strength. For this, the instability factor kc is determined, which depends primarily on the component slenderness and the support type.
As an alternative to the equivalent member method, this article describes the possibility to determine the internal forces of a wall at risk of buckling according to the second-order analysis, taking imperfections into account, and to subsequently perform the cross-section design for bending and compression.
RFEM and RSTAB provides two different methods for the superposition of load cases. Using load combinations, the loads of individual load cases are superimposed and calculated in a "big load case". On the other hand, result combinations only combine the results of the individual load cases. This article describes the with the basis of defining result combinations and explain it in detail on two examples.
In addition to the reinforced concrete design according to EN 1992‑1‑1, RF-/FOUNDATION Pro allows you to perform geotechnical designs according to EN 1997‑1. In RF-/FOUNDATION Pro, the design of the allowable soil pressure is performed as a ground failure resistance design. If you select CEN as National Annex, you have two options for defining the ground failure resistance. First, you can directly specify the allowable characteristic value of the soil pressure σRk. Second, there is also the option to analytically determine the bearing capacity according to [1], Annex D.
My previous article Result Combinations 1 explained the basic principles of result combinations on simple examples. This article describes a further application case that combines the definition options of Examples 1 and 2. Likewise, the effort should be compared to a combination by means of load combinations.
If an aluminum member section is comprised of slender elements, failure can occur due to the local buckling of the flanges or webs before the member can reach full strength. In the add-on module RF-/ALUMINUM ADM, there are now three options for determining the nominal flexural strength for the limit state of local buckling, Mnlb, from Section F.3 in the 2015 Aluminum Design Manual. The three options include sections F.3.1 Weighted Average Method, F.3.2 Direct Strength Method, and F.3.3 Limiting Element Method.
Using RF-/FOUNDATION Pro, it is possible to perform geotechnical design according to EN 1997‑1 [1] for single foundations. Subsequently, the program displays detailed information about the influence of the ground water level on the selected design according to EN 1997‑1.
Using RF-/FOUNDATION Pro, it is possible to perform geotechnical design according to EN 1997-1 [1] for single foundations. The following article explains the design of highly eccentric loading in the foundation core according to DIN EN 1997‑1, A 6.6.5 (see [3]).
RF-/JOINTS Timber – Timber to Timber allows you to design main-connected beam joints. This article explains the determination of forces in screws of a beam connected to a torsionally rigid main beam.
In a multi-modal response spectrum analysis, it is important to determine a sufficient number of eigenvalues of the structure and to consider their dynamic responses. Regulations such as EN 1998‑1 [1] and other international standards require the activation of 90% of the structural mass. This means: to determine so many eigenvalues that the sum of the effective modal mass factors is greater than 0.9.
In RF-DYNAM Pro - Equivalent Loads, the equivalent seismic loads can be calculated according to different standards. By calculating the equivalent loads for each eigenmode, it is not directly possible to obtain the transversal shear for each story to perform an analysis afterwards. The following example describes the option to calculate the transversal shear quickly and efficiently.
- 001530
- Modeling | Loading
- RFEM 5
-
- RSTAB 8
- RX-TIMBER Glued-Laminated Beam 2
- RX-TIMBER Roof 2
- RX-TIMBER Continuous Beam 2
- RX-TIMBER Purlin 2
- RX-TIMBER Frame 2
- RX-TIMBER Column 2
- RX-TIMBER Brace 2
- Buildings
- Concrete Structures
- Steel Structures
- Timber Structures
- Process Manufacturing Plants
- Temporary Structures
- Structural Analysis & Design
- Eurocode 1
- Eurocode 0
In Germany, DIN EN 1991-1-3 with National Annex DIN EN 1991-1-3/NA regulates snow loads. The standard applies to civil engineering works at altitudes of up to 1,500 m above sea level.
There are several options for calculating a semi-rigid composite beam. They differ primarily in the type of modeling. Whereas the Gamma method ensures simple modeling, additional efforts are required when using other methods (for example, shear analogy) for the modeling which are, however, offset by the much more flexible application compared to the Gamma method.
This article describes how a flat slab is generated as a 2D model in RFEM and the loading is applied according to Eurocode 1. The load cases are combined according to Eurocode 0 and calculated linearly. In the RF-CONCRETE Surfaces add-on module, the bending design of the slab is performed while taking into account the standard requirements of Eurocode 2. The reinforcement is complemented by a rebar reinforcement for areas that are not covered by the mesh basic reinforcement.