Slip-critical connection (AISC)

Subcode: LRFD

Type of connection: Bolted splice connection

Unit system: Metric

Designed acc. to: AISC 360-16

Investigated: High-strength bolts in slip-critical connection

Plate material: A709, Gr. 50

Bolts: 5/8'' A325

Geometry

Applied load

Bolted splice slip-critical connection is loaded by tension for the slip resistance to be utilized at 100 %.

Procedure

Concentrically loaded splice bolted connection is designed so that the slip resistance of high strength bolts (AISC 360-16 – J3.8) is exhausted first.

Manual calculation

Bolt strength

The design slip strength of the connection is 9 ∙ 58.1 = 522.9 kN.

Strength of plates in tension

$$\phi R_n = \phi F_y A_g = 0.9 \cdot 344.7 \cdot 2000 = 620.46 \, \textrm{kN}$$

Check in IDEA StatiCa Connection

The bolts are, beside the shear force, loaded also by the tensile force due to the deformation of plates. This decreases the slip resistance of bolts according to AISC 360-16 – J3.9. The resistance of connection in IDEA StatiCa Connection is 497 kN.

Comparison

The resistance in IDEA StatiCa Connection is decreased by the tensile forces in bolts which are neglected in manual calculation. The resistances in IDEA and manual calculation are 497 kN and 523 kN, respectively. The difference is 5 % to the safe side.