RF-/JOINTS Steel - Pinned | Design

Fin plate connections are a popular form of pinned steel connection and are commonly used for secondary beams in steel structures. They can be used easily in beam structures arranged on the top edge (for example, working platforms). Manufacturing expenditures in the workshop as well as the onsite assembly costs are normally manageable. The design seems to be completed easily and quickly, but it has to be put into perspective to a certain extent in the following text. Moreover, this connection type is basically possible as a pinned beam-to-beam or pinned beam-to-column connection; the former case is the more common one in design practice.

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.

After opening the add-on module, it is necessary to select the joint group (Pinned Joints), then the joint category and joint type (web cleat, fin plate, short end plate, end plate with cleat). Then, you can select the nodes for design in the RFEM/RSTAB model. RF-/JOINTS Steel - Pinned automatically recognizes the joint members and determines from its location whether they are columns or beams.

It is possible to exclude particular members from the calculation, if required. Structurally similar connections can be designed for several nodes at the same time. Loads require selection of the governing load cases, load combinations, or result combinations. Alternatively, you can enter the cross‑section and load data manually. In the last input window, the connection is configured step by step.

General

• Beam to Column joint category: connection possible on the column flange as well as on the column web
• Beam to Beam joint category: optional arrangement of ribs on the opposite side
• Bolt sizes from M12 to M36 with the strength grades 4.6, 5.6, 8.8, and 10.9
• Arbitrary bolt hole spacing and edge distances
• Notching of the beam is possible
• Connection with pure shear loading, pure normal force load (tension joint), or possible combination of normal and shear forces
• Checking compliance with the requirements for pinned joints
• Check of the minimum and maximum bolt hole spacing and edge distances

Web cleat connections

• One or two vertical and up to 10 horizontal bolt rows possible at each leg
• Wide range of equal and unequal angles
• Possible to modify angle orientation
• Designs:
  • Shear, bearing resistance, and tension design of bolts
  • Shear, bending, and tension design of angles considering deduction of bolt hole
  • Shear and tension design of girder web considering deduction of bolt hole
  • Tension transmission into the column with the T-stub model
  • Notching at the critical section

Fin plate connection

• One or two vertical and up to 10 horizontal bolt rows are possible
• Flexible size of the fin plate
• Location of the fin plate can be modified
• Designs:
  • Shear and bearing resistance design of bolts
  • Shear, bending, and tension design of fin plates considering deduction of bolt hole
  • Stability analysis of long, slender fin plates
  • Shear and tension design of girder web considering deduction of bolt hole
  • Weld as fillet weld
  • Notching at the critical section

End plate connection

• Two or four vertical and up to 10 horizontal bolt rows
• Flexible size of the end plate
• Location of the fin plate can be modified
• Designs:
  • Shear, bearing resistance, and tension design of bolts
  • Shear and bending design of end plates considering deduction of bolt hole
  • Shear and tension design of girder web
  • Tension transmission into the column with the T-stub model
  • Weld as fillet weld
  • Notching at the critical section

End plate connection with cleat

• Fixation of the beam by end plate with two bolts
• Flexible size of cleat and end plate
• Designs:
  • Load introduction into the beam according to EN 1993-1-5, Chapter 6
  • Support of the stabilizing moment by the bolts and welds at the end plate
  • Cleat
  • Cleat welds as fillet welds
  • Tension transmission into the column with the T-stub model

All joint types are considered with the moment release at the column flange, or at the column web in the case of a rotated column. Therefore, the module determines the eccentric moment of a web cleat and fin plate connection, which additionally affects the bolt group at the girder flange.

Further eccentric moments may result from the locations of the angles and sheets. In the case of cleat connection, the forces are transferred separately. Shear forces act on the cleat; tension forces and stabilizing moment are assigned to the bolts. Before the calculation, the connection is checked for geometrical plausibility; for example, the bolt hole spacing and edge distance of the bolts.