Utilizing the Steel Design Add-on, steel design is possible according to the AISC 360-22 standard. The following article will compare the result output when calculating lateral torsional buckling according to Chapter F vs. an Eigenvalue Analysis.
The evaluation of story drift in a building is crucial to ensure acceptable structural performance by limiting the drift amount. Excessive drift has the potential to induce system instability and may cause damage to nonstructural components such as partitions. This article outlines the procedure for establishing interstory drift according to ASCE 7-22 and the Building Model add-on in RFEM 6.
The ASCE 7-22 Standard [1], Sect. 12.9.1.6 specifies when P-delta effects should be considered when running a modal response spectrum analysis for seismic design. In the NBC 2020 [2], Sent. 4.1.8.3.8.c gives only a short requirement that sway effects due to the interaction of gravity loads with the deformed structure should be considered. Therefore, there may be situations where second-order effects, also known as P-delta, must be considered when carrying out a seismic analysis.
The three types of moment frames (Ordinary, Intermediate, Special) are available in the Steel Design add-on of RFEM 6. The seismic design result according to AISC 341-22 is categorized into two sections: member requirements and connection requirements.
Using the Timber Design add-on, timber column design is possible according to the 2018 NDS standard ASD method. Accurately calculating timber member compressive capacity and adjustment factors is important for safety considerations and design. The following article will verify the maximum critical buckling strength calculated by the Timber Design add-on using step-by-step analytical equations as per the NDS 2018 standard including the compressive adjustment factors, adjusted compressive design value, and final design ratio.
The Steel Design add-on in RFEM 6 now offers the ability to perform seismic design according to AISC 341-16 and AISC 341-22. Five types of seismic force-resisting systems (SFRS) are currently available.
The three types of moment frames (Ordinary, Intermediate, Special) are available in the Steel Design add-on of RFEM 6. The seismic design result according to AISC 341-16 is categorized into two sections: member requirements and connection requirements.
Moment frame design according to AISC 341-16 is now possible in the Steel Design add-on of RFEM 6. The seismic design result is categorized into two sections: member requirements and connection requirements. This article covers the required strength of the connection. An example comparison of the results between RFEM and the AISC Seismic Design Manual is presented.
The design of an Ordinary Concentrically Braced Frame (OCBF) and a Special Concentrically Braced Frame (SCBF) can be carried out in the Steel Design add-on of RFEM 6. The seismic design result according to AISC 341-16 and 341-22 is categorized into two sections: Member Requirements and Connection Requirements.
When it comes to wind loads on building type structures as per ASCE 7, numerous resources can be found to supplement design standards and aid engineers with this lateral load application. However, engineers may find it more difficult to find similar resources for wind loading on non-building type structures. This article will examine the steps to calculate and apply wind loads as per ASCE 7-22 on a circular reinforced concrete tank with a dome roof.
Both the determination of natural vibrations and the response spectrum analysis are always performed on a linear system. If nonlinearities exist in the system, they are linearized and thus not taken into account. They are caused by, for example, tension members, nonlinear supports, or nonlinear hinges. This article shows how you can handle them in a dynamic analysis.
Compliance with building codes, such as Eurocode, is essential to ensure the safety, structural integrity, and sustainability of buildings and structures. Computational Fluid Dynamics (CFD) plays a vital role in this process by simulating fluid behavior, optimizing designs, and helping architects and engineers meet Eurocode requirements related to wind load analysis, natural ventilation, fire safety, and energy efficiency. By integrating CFD into the design process, professionals can create safer, more efficient, and compliant buildings that meet the highest standards of construction and design in Europe.
Windbreak structures are special types of fabric structures which protect the environment from harmful chemical particles, abate wind erosion, and help to maintain valuable sources. RFEM and RWIND are used for wind-structure analysis as one-way fluid-structure interaction (FSI).
This article demonstrates how to structural design windbreak structures using RFEM and 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.
This article discusses the options available for determining the nominal flexural strength, Mnlb for the limit state of local buckling when designing according to the 2020 Aluminum Design Manual.
Webservice is a communication between machines and programs. This communication is provided via the network and can, therefore, be used by any program that can send and receive strings via the HTTP protocol. RFEM 6 and RSTAB 9 provide an interface based on these cross-platform webservices. This tutorial shows the basics using the VBA programming language.
The effects due to snow load are described in the American standard ASCE/SEI 7-16 and in Eurocode 1, Parts 1 through 3. These standards are implemented in the new RFEM 6 program and the Snow Load Wizard, which serves to facilitate the application of snow loads. In addition to this, the most recent generation of the program allows the construction site to be specified on a digital map, thus allowing the snow load zone to be imported automatically. These data are, in turn, used by the Load Wizard to simulate the effects due to the snow load.
In this article, the adequacy of a 2x4 dimension lumber subject to combined biaxial bending and axial compression is verified using the RF-/TIMBER AWC add-on module. The beam-column properties and loading are based on example E1.8 of AWC Structural Wood Design Examples 2015/2018.
If a member is supported laterally to prevent buckling due to a compressive axial force, it must be ensured that the lateral support is actually able to prevent buckling. Therefore, the aim of this article is to determine the ideal spring stiffness of a lateral support using the Winter model.
Utilizing the RF-STEEL AISC add-on module, steel member design is possible according to the AISC 360-16 standard. The following article will compare the results between calculating lateral torsional buckling according to Chapter F and Eigenvalue Analysis.
Using the RF-TIMBER AWC module, timber column design is possible according to the 2018 NDS standard ASD method. Accurately calculating timber member compressive capacity and adjustment factors is important for safety considerations and design. The following article will verify the maximum critical buckling in RF-TIMBER AWC using step-by-step analytical equations as per the NDS 2018 standard including the compressive adjustment factors, adjusted compressive design value, and final design ratio.
Both the determination of natural vibrations and the response spectrum analysis are always performed on a linear system. If nonlinearities exist in the system, they are linearized and thus not taken into account. Straight tension members are very often used in practice. This article will show how you can display them approximately correctly in a dynamic analysis.
In order to consider inaccuracies regarding the position of masses in a response spectrum analysis, standards for seismic design specify rules that have to be applied in both the simplified and multi-modal response spectrum analyses. These rules describe the following general procedure: The story mass must be shifted by a certain eccentricity, which results in a torsional moment.
When evaluating line support forces, implausible diagrams sometimes arise at first glance. In particular, for variable loads at locations that also have a nodal support, at division points and edge locations of supported lines, the results sometimes show unexpected support reactions. Using the function of the linear smooth distribution in Project Navigator – Display does not always lead to the expected result diagram.
Using RF-CONCRETE Members, concrete column design is possible according to ACI 318-14. Accurately designing concrete column shear and longitudinal reinforcement is important for safety considerations. The following article will confirm the reinforcement design in RF-CONCRETE Members using step-by-step analytical equations as per the ACI 318-14 standard, including required longitudinal steel reinforcement, gross cross-sectional area, and tie size/spacing.
When introducing and transferring horizontal loads such as wind or seismic loads, increasing difficulties arise in 3D models. To avoid such issues, some standards (for example, ASCE 7, NBC) require the simplification of the model using diaphragms that distribute the horizontal loads to structural components transferring loads, but cannot transfer bending themselves (called "Diaphragm").
The ASCE 7-16 standard requires both balanced and unbalanced snow load case scenarios for a structure's design consideration. While this may be more intuitive for flat or even gable/hip type roofs, the determination of snow loads is increasingly difficult for arch roofs due to complex geometry. However, with guidance from ASCE 7-16 on snow load calculations for curved roofs and RFEM's efficient load application tools, it is possible to consider both balanced and unbalanced snow loads for a reliable and safe structure design.
As gravity loads act on a structure, lateral displacement occurs. In turn, a secondary overturning moment is generated as the gravity load continues to act on the elements in the laterally displaced position. This effect is also known as "P-Delta (Δ)". Sec. 12.9.1.6 of the ASCE 7-16 Standard and the NBC 2015 Commentary specify when P-Delta effects should be considered during a modal response spectrum analysis.
When it comes to wind loads on building type structures as per ASCE 7, numerous resources can be found to supplement design standards and aid engineers with this lateral load application. However, engineers may find it more difficult to find similar resources for wind loading on non-building type structures. This article will examine the steps to calculate and apply wind loads as per ASCE 7-16 on a circular reinforced concrete tank with a dome roof.