Home Support & Learning Support Knowledge Base Considering the Joint Slip in Parametric Timber Cross-Sections
Considering the Joint Slip in Parametric Timber Cross-Sections
Tips & Tricks
New
02/26/2021
000612
In timber design, beams are often built up of several timber elements. The individual elements can be connected by glue, nails, bolts, or dowels. A glued connection is to be assumed as rigid. In the case of dowel‑type fasteners, the joint is compliant (slip joint) and the cross‑section properties of the connected elements cannot be fully applied.
In RFEM 5 and RSTAB 8, it is possible to consider the compliance of the connections of built‑up members in the individual layers. This is done by entering the reduction factor gamma, which can be determined by means of the ‘gamma method’, for example according to EN 1995‑1‑1 (Annex B) or DIN 1052:2008 (8.6.2). This factor takes into account a reduction of the parallel axis theorem components of the cross‑section parts from which an effective bending stiffness results.
In addition, it is possible to assign different materials to the individual cross‑section. To do this, select the option ‘Hybrid’, and then select one of these materials as reference material to determine the ideal cross‑section properties.
Author

Dipl.-Ing. (FH) Gerhard Rehm
Product Engineering & Customer Support
Mr. Rehm is responsible for the development of products for timber structures, and provides technical support for customers.
Keywords
Composite timber cross-sections Flexibility Gamma method Composite beam
Links
Contact us
Do you have questions or need advice?
Contact our free e-mail, chat, or forum support or find various suggested solutions and useful tips on our FAQ page.
Recommended Events
Timber Beam and Surface Structures | Part 1: Modeling, Load Input, Combinatorics
Webinar 05/04/2021 2:00 PM - 3:00 PM CEST
Eurocode 3 | Steel structures according to DIN EN 1993-1-1
Online Training 05/06/2021 8:30 AM - 12:30 PM CEST
Eurocode 2 | Concrete structures according to DIN EN 1992-1-1
Online Training 05/12/2021 8:30 AM - 12:30 PM CEST
Eurocode 5 | Timber structures according to DIN EN 1995-1-1
Online Training 05/20/2021 8:30 AM - 12:30 PM CEST
RFEM | Structural dynamics and earthquake design according to EC 8
Online Training 06/02/2021 8:30 AM - 12:30 PM CEST
Videos
Models to Download
Knowledge Base Articles

New
Often, models are needed in several projects, like the purlin with columns and knee braces in this example. The dimensions can be changed directly in RFEM or RSTAB by shifting the nodes.Screenshots
Product Features Articles

The cross-section resistance design analyzes tension and compression along the grain, bending, bending and tension/compression as well as the strength in shear due to shear force.
The design of structural components at risk of buckling or lateral-torsional buckling is performed according to the Equivalent Member Method and considers the systematic axial compression, bending with and without compressive force as well as bending and tension. Deflection of inner spans and cantilevers is compared to the maximal allowable deflection.
Separate design cases allow for a flexible and stability analysis of members, sets of members, and loads.
Design-relevant parameters such as the stability analysis type, member slendernesses, and limit deflections can be freely adjusted.
Frequently Asked Questions (FAQ)
- How can I model a timber-concrete composite floor?
- Is it possible to perform design for a timber-concrete composite cross-section?
- How is the coupling between the individual layers controlled in the RF‑LAMINATE add-on module?
- Is it possible to model a semi-rigid composite beam with a line release using members in RFEM?
- Can the properties, such as B. the cross -section or the surface thickness as well as the material of a surface of an existing element for a new element?
- I design timber components. The deformations of load combinations deviate from the manual calculation exactly by the factor of the material partial safety factor. Why?
- How can I set the deformation coefficient kdef in the program?
- After opening a duopitch roof beam from RX‑TIMBER in RFEM/RSTAB, it is displayed with a gap in the apex zone. Does this affect the calculation?
- Can I consider a shear force reduction with the RF‑/TIMBER Pro add-on module?
- Are the models and presentations from Info Day 2020 freely available, and can you send them to me?
Customer Projects
Associated Products