In timber design, beams are often built from several timber elements. The individual elements can be connected with 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.
Table 3.1 of EN 1993‑1‑8:2010‑12 defines the nominal values of the yield strength and the ultimate limit strength of bolts. The bolt classes given here are 4.6, 4.8, 5.6, 5.8, 6.8, 8.8, 10.9. The note for this table states that the National Annex may exclude certain bolt classes. For the NA of Germany, these are the bolt classes 4.8, 5.8, and 6.8.
RFEM offers the following options to design a pinned end plate connection. First, there is the option in RF-JOINTS Steel - Pinned to enter the corresponding parameters quickly and easily to receive a documented analysis, including graphics. It is also possible to model such a connection individually in RFEM and then to evaluate or manually design the results. In the following example, the particularities of this modeling will be explained and the shear forces of the bolts will be compared to the corresponding results from RF-JOINTS Steel - Pinned.
In this example, the design resistance of an end plate according to EN 1993-1-8 [1] is to be determined; the other components are not described here. To check the results, the dimensions of the connection IH 3.1 B 30 24 of Typified Connections [2] were used. S 235 material and bolts with strength 10.9 are used.
In RF-JOINTS Timber – Steel to Timber, you can consider the possible minimum slippage of bolts in the case of guide pins. In RFEM, this slippage is taken into account using the flexibility in member end releases.