Using an example of a steel fiber-reinforced concrete slab, this article describes how the use of different integration methods and of a different number of integration points affects the calculation result.
In many frame and truss structures, it is no longer sufficient to use a simple member. You often have to consider cross-section weakenings or openings in solid beams. In such cases, you can use the "Surface Model" member type. It can be integrated into the model like any other member and offers all the options of a surface model. The present technical article shows the application of such a member in an existing structural system and describes the integration of member openings.
As you may already know, RFEM 6 offers you the possibility to consider material nonlinearities. This article explains how to determine internal forces in slabs modeled with nonlinear material.
In this paper, a novel approach was developed to generate CFD models at the community-level by integrating building information modeling (BIM) and geographical information systems (GIS) to automate the generation of a high-resolution 3-D community model to be employed as an input for a digital wind tunnel using RWIND.
RWIND 2 is a program for generating wind loads based on CFD (Computational Fluid Dynamics). The wind flow numerical simulation is generated around any building, including irregular or unique geometry types, to determine the wind loads on surfaces and members. RWIND 2 can be integrated with RFEM/RSTAB for the structural analysis and design or as a stand-alone application.
RFEM and RSTAB programs provide parameterized input as an advantageous product feature to create or adjust models by means of variables. This article will show you how to define global parameters and use them in formulas to determine numerical values.
RWIND 2 is a program for generating wind loads based on CFD (Computational Fluid Dynamics). The wind flow numerical simulation is generated around any building, including irregular or unique geometry types, to determine the wind loads on surfaces and members. RWIND 2 can be integrated with RFEM/RSTAB for the structural analysis and design or as a stand-alone application.
The add-on modules for designing structural member components according to national, European, and international standards also show design results in addition to numerical output in tables graphically, as diagrams displayed on the framework.
The "4.0 Results - Summary" table displays the infinity norm at the end of the load case results. The norm is used to estimate the largest eigenvalue of a structure. The largest eigenvalue of a structure is estimated by numerical analysis, as accurate determination can be very time-consuming.
The following study compares the wind pressure on a tall building obtained by RWIND Simulation with the results published by Dagnew et al. at the 11th Americas Conference on Wind Engineering in June, 2009. In this paper, the Commonwealth Advisory Aeronautical Council (CAARC) building is used as a model, and the results of several different numerical methods are compared with experimental data obtained from wind tunnels.
This article presents a bending beam with a circular opening analyzed using the numerical method. As a reference point, there is an example of a perforated beam from [1]. In our case, the 3D model was simplified to a two-dimensional discretization.
If a section is not on a straight line but on a curved or angled line, this line has to be defined accordingly as a polyline or a curved line. You can define the section along a line using the "Create Section Numerically" function.
RFEM facilitates modeling by the automatic integration of objects into surfaces. However, it is impossible to integrate the objects automatically in the case of curved surfaces. For manual integration, select the relevant surfaces and click the "Edit Surfaces" option in the shortcut menu; then, in the "Integrated" tab, you can integrate the relevant objects using the "Select" function. This way, you can avoid error messages caused by non‑integrated objects when starting the calculation.
In RFEM, there are a file‑based and a direct DXF interface. The file-based DXF interface allows you to export the data in a DXF file that is transferred directly into an open AutoCAD file. In the interface dialog box, you can select which data are to be exported (results as isolines, result values, or finite element mesh with boundary and integration lines).
If a model should contain members with elastic foundations, the contact forces and moments are displayed in numerical form in the result windows. The graphical display of results is specified by the "Members" entry in the Results Navigator.
During the cooperation between the structural and design engineers, the DXF format is often used if there is no direct interface. However, the geometrical data of these DXF files are not always accurate. For example, an inaccuracy in the third decimal place is not noticeable, but it can lead to numerical problems when generating the FE mesh in RFEM.