Job: to design a beam to column flange simple connection with high strength friction bolts to a

given shear force Ved.

Preliminary Data:

Steel S275

Beam IPE 450

Column HEA 340

Plate 12mm

VEd=550kN

Column HEA340, S275

Depth

Width

Thickness of the web

Thickness of the flange

Fillet radius

Area

hc 330mm:=

bc 300mm:=

twc 9.5mm:=

tfc 16.5mm:=

r 27mm:=

Ac 133.5mm2

:=

Beam IPE450, S275

Depth

Width

Thickness of the web

Thickness of the flange

Fillet radius

Area

hb 450mm:=

bb 190mm:=

twb 9.4mm:=

tfb 14.6mm:=

rb 21mm:=

Ab 98.8mm2

:=

Plate S275

tp 12mm:=Thickness

Yield s trength

Ultimate tensile strength

fy 275N

mm2

:=

fup 430N

mm2

:=

HSF Bolts M22 grade 10.9:

Tensile stress area As 303mm2

:=

Diameter of the shank d 22mm:=

Diameter of the holes d0 24mm:=

Diameter of the washer dw 50mm:=

fyb 900N

mm2

:=Yield s tregth

Ultimate tensile stregth fub 1000N

mm2

:=

αv 0.5:=

Design Shear Force:

VEd 550kN:=

Partial Safety Factors:

γM0 1:=

γM2 1.25:= (for shear resistance in ULS)

γM3 1.25:=

γMu 1.1:= (for tying resistance in ULS)

Abstract - High strength friction bolts

High strength friction bolts produce compressive stress on the connecting

plates, increasing their frictional resistance and allowing the transfer of shear force

between them.

Preloading of bolts:

n 4:= no. of bolts

Fp.Cd n 0.7⋅ fub⋅ As⋅ 848.4 kN⋅=:=

Resistance of the high strength friction bolts connection between plates and

column

Number of friction faces:

nf 2:=

Slip factor µ for treated surfaces:

µ 0.5:=

Friction force for one bolt:

Fs.Rd

nf µ⋅ Fp.Cd⋅

γM3

678.72 kN⋅=:=

Friction will resist the Shear Force.

Conclusion :

High strength friction bolts are used because of their greater stiffness,their

capacity to bear alternative forces and their better fatigue resistance compared with

normal bolts.

They need more care and trained workers and they are more expensive.

So,in our case,we better use the normal bolted connections.

The rest of the checkings will be done like they were done for normal

bolted connection.

Weld design(S275)

a 0.48 twb⋅ 4.512 mm⋅=:=

Choose as a=5mm welding.

Plate design

The plate height

hp hb 2 100⋅ mm− 250 mm⋅=:=

From Eurocode 1993-1-8:

Minimum

e1 1.2 d0⋅ 28.8 mm⋅=:=

e2 1.2 d0⋅ 28.8 mm⋅=:=Maximum

e1 4 tp⋅ 40mm+ 88 mm⋅=:=

e2 4tp 40mm+ 88 mm⋅=:=

Choose e1 80mm:= ., e2 50mm:=p1 2.2d0 52.8 mm⋅=:=

p2 2.4d0 57.6 mm⋅=:=

p1 hp e1− e1− 90 mm⋅=:=

.

.

p2 e2 tfb+ e2+ 114.6 mm⋅=:=

p2 115mm:=

The plate base will have the dimension:

bp e2 p2+ e2+ 215 mm⋅=:=

tp 12mm:=

We will have one plate 250x215x12 with 4 bolts.

Joint shear resistance

Beam Web in Shear

Av 0.9 hp⋅ twb 2 tfb⋅+( )⋅ 8.685 103

× mm2

⋅=:=

VRd7

Av fyb⋅1

3⋅

γM0

4.513 103

× kN⋅=:=

End plate in bearing

e1

3d0

1.111=p1

3 d0⋅

1

4− 1=

fub

fup

2.326=

αb is the minimum of the above 3 relations:

αb minp1

3 d0⋅

1

4−

e1

3d0

, fub

fup

,

1=:=

2.8e2

d0

⋅ 1.7− 4.133=

k1 min 2.5 2.8e2

d0

⋅ 1.7−,

2.5=:=

FbRd

k1 αb⋅ fup⋅ d⋅ tp⋅

γM2

227.04 kN⋅=:=

VRd2 0.8 4⋅ FbRd⋅ 726.528 kN⋅=:=

Joint tying resistance

Bolts in shear

The bolts are not subjected to shear.

End Plate in Bearing

αb2 mine2

3d0

fub

fup

, 1,

0.694=:=

k12 min 2.8e1

d0

⋅ 1.7− 1.4p1

d0

1.7−, 2.5,

2.5=:=

Fb.Rd.u.hor

k12 αb2⋅ fup⋅ d⋅ tp⋅

γMu

179.167 kN⋅=:=

NRd.u.2 n Fb.Rd.u.hor⋅ 716.667 kN⋅=:=

Column Flange in Bearing

e2c e2 95mm+ 145 mm⋅=:=

αb3 mine2c

3d0

fub

fup

, 1,

1=:=

k13 min 1.4p1

d0

1.7− 2.5,

2.5=:=

Fb.Rd.u.hor2

k1 αb⋅ fup⋅ d⋅ tfc⋅

γMu

354.75 kN⋅=:=

NRd.u.5 n Fb.Rd.u.hor2⋅ 1.419 103

× kN⋅=:=

Joint shear resistance•VRd2 726.528 kN⋅=

VRd7 4.513 103

× kN⋅=

Joint tying resistance•

NRd.u.2 716.667 kN⋅=

NRd.u.5 1.419 103

× kN⋅=

All the resistances have values above the design load value,so the design

is good.