FIN PLATE CONNECTION DESIGN
Design according to EN 1993-1-8
Method = Select design approach per EN 1990
1. Member and Plate Properties
Fin Plate Properties:
tp = mm Fin plate thickness
fyp = MPa Fin plate yield strength (S355 steel)
fup = MPa Fin plate ultimate tensile strength
Main Member (Beam Web) Properties:
tw = mm Beam web thickness
fyw = MPa Beam web yield strength
fuw = MPa Beam web ultimate tensile strength
Figure 1: Geometry
Fin Plate Dimensions
2. Bolt Properties
d = mm Bolt nominal diameter
d0 = d + 2 = 22.00 mm Bolt hole diameter
fub = MPa Bolt ultimate tensile strength (Grade 8.8)
As = mm² Bolt tensile stress area (for M20)
Ab = π·d²/4 = 314.16 mm² Bolt gross cross-sectional area
3. Geometry
n = Number of bolts in a vertical row
e1 = mm End distance (along the width of fin-plate)
e2 = mm Edge distance (along the length of fin-plate)
p1 = mm Pitch (spacing in direction of shear force)
p2 = mm Gauge (spacing in direction of axial force)
g = p2 = 0 mm Gauge is equal to p₂ = 0.0mm for single line of bolts
Derived Geometry:
Lp = e1 + (n − 1)·p1 + e1 = 250.00 mm Fin plate length
bp = e2 + p2 + e2 = 140.00 mm Fin plate width
4. Applied Loads
V* = kN Factored shear force (in-plane)
N* = kN Factored axial force (tension positive)
Select axial load direction:
Design Strengths (Clause 9.3.2):
Ps = As·fub/1.25 = 156.80 kN Bolt shear strength (single shear)
Pt = 0.9·As·fub/1.25 = 141.12 kN Bolt tension strength (Clause 9.3.3.1)
kb = min(e1/(3·d0); p1/(3·d0) − 0.25; fub/fup; 1.0) = 0.55 kb for bearing (Clause 9.3.3.1)
Bolt Bearing Strengths:
Pbb = kb·d·tp·fup/1.25 = 84.63 kN Bolt bearing strength (fin plate)
Pbw = kb·d·tw·fuw/1.25 = 84.63 kN
Bolt Resistance Checks:
Pbolt_shear = n·Ps = 627.20 kN Total bolt shear resistance
Pbolt_tension = n·Pt = 564.48 kN Total bolt tension resistance
Shear Check: V* ≤ Pbolt_shear → Check = 1 (1 = Ok; 0 = Not Ok)
Tension Check: N* ≤ Pbolt_tension → Check = 1 (1 = Ok; 0 = Not Ok)
Pbolt_bearing_p = n·Pbb = 338.52 kN Total bolt bearing resistance (fin plate)
Combined Loading Check (Fin Plate): Interaction = V*/Pbolt_shear + N*/Pbolt_bearing_p = 0.524 (≤ 1.0)
Pbolt_bearing_w = n·Pbw = 338.52 kN Total bolt bearing resistance (beam web)
Combined Loading Check (Bolts): Interaction = V*/Pbolt_shear + N*/Pbolt_bearing_w = 0.524 (≤ 1.0)
Block Shear (Clause 9.10.4.3):
Lt,vert = Lp − e1 = 210.00 mm Length of tension surface
At,block = tp·e2 = 300.00 mm² Area of tension surface
Av,block = tp·(Lp − (n − 1)·d0 − e1) = 1940.00 mm² Area of shear surface
Vblock_shear_resist = (0.6·fup·Av,block/1.25) + (fup·At,block/1.25) = 873.92 kN Block shear resistance
Combined Block Shear Check: Interaction = V*/Vblock_shear_resist + N*/Ptension_rup = 0.550 (≤ 1.0)
Fin Plate Tension Rupture:
Ant = (Lp − n·d0)·tp = 960.00 mm² Net area for tension rupture
Ptension_rup = Ant·fup/1.25 = 376.32 kN Tension rupture resistance
Tension Rupture Check: N* ≤ Ptension_rup → Check = 1 (1 = Ok; 0 = Not Ok)
Fin Plate Shear Rupture:
Anv = (bp − d0)·tp = 1920.00 mm² Net area for shear rupture
Pshear_rup = 0.6·Anv·fup/1.25 = 451.58 kN Shear rupture resistance
Shear Rupture Check: V* ≤ Pshear_rup → Check = 1 (1 = Ok; 0 = Not Ok)
Summary of Results:
Design Shear Force = V* = 150.00 kN
Design Axial Force = N* = 50.00 kN
Total Bolt Shear Resistance = 627.20 kN
Total Bolt Tension Resistance = 564.48 kN
Total Bolt Bearing Resistance (Fin Plate) = 338.52 kN
Total Bolt Bearing Resistance (Beam Web) = 338.52 kN
Block Shear Resistance = 873.92 kN
Tension Rupture Resistance = 376.32 kN
Shear Rupture Resistance = 451.58 kN
Combined Loading Final Check:
Overall Interaction Ratio = max( V*/Pbolt_shear + N*/Pbolt_tension; V*/Pbolt_shear + N*/Pbolt_bearing_p; V*/Pbolt_shear + N*/Pbolt_bearing_w; V*/Vblock_shear_resist + N*/Ptension_rup; N*/Ptension_rup; V*/Pshear_rup ) = 0.550 (≤ 1.0)
Overall Status: Overall Interaction Ratio = 0.550 (≤ 1.0 = Ok)