In Germany, DIN EN 1991-1-4 with the National Annex DIN EN 1991-1-4/NA regulates the wind loads. The standard applies to civil engineering works up to an altitude of 300 m.
When calculating regular structures, data input is often not complicated but time-consuming. Input automation can save valuable time. The task described in the present article is to consider the stories of a house as single construction stages. Data is entered using a C# program so that the user does not have to enter the elements of the individual floors manually.
The vibration design of cross‑laminated timber plates often governs for wide-span ceilings. The advantage of timber as a lighter material compared to concrete is turned into a disadvantage here, since a high mass is advantageous for a low natural frequency.
With the orthotropic elastic-plastic material model, you can calculate solids with plastic material properties in RFEM 5 and evaluate them according to the Tsai‑Wu failure criterion. The Tsai-Wu criterion is named for Stephen W. Tsai and Edward M. Wu, who published it in 1971 for plane stress states.
When modeling frame structures, RFEM and RSTAB provide various options for controlling the transfer of internal forces and moments at the connection points of members. You can use the member types to determine whether only forces act on the connected members, or whether moments act on them as well. In addition, you can use hinges to exclude specific internal forces from the transfer. One special form is scissor hinges, which allow for realistic modeling of roof structures, for example.
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.
Until now, the prestress load type had always been an initial prestress in Dlubal Software programs. The defined load magnitude was applied and, depending on the stiffness of the surrounding system, prestress remained more or less as an axial force in the cable.
To better distinguish between the different layer compositions (for example, for walls and ceilings), you can assign user‑defined colors and textures to each composition.
The most common causes of unstable models are failing member nonlinearities such as tension members. As the simplest example, there is a frame with supports on the column footing and moment hinges on the column head. This unstable system is stabilized by a cross bracing of tension members. In the case of load combinations with horizontal loads, the system remains stable. However, if it is loaded vertically, both tension members fail and the system becomes unstable, which causes a calculation error. You can avoid such an error by selecting the exceptional handling of failing members under "Calculate" → "Calculation Parameters" → "Global Calculation Parameters".
Our webservice offers users the opportunity to communicate with RFEM 6 and RSTAB 9 using various programming languages. Dlubal's high-level functions (HLFs) allow you to expand and simplify the WebService's functionality. In line with RFEM 6 and RSTAB 9, using our WebService makes the engineer's work easier and faster. Check it out now! This tutorial shows you how to use the C# library by means of a simple example.