5. Steel Joint Design (Fin Plate)

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C Clause F FIN PLATE BE Configurat Column Beam Connectio Fin Plate EAM-TO-CO tion Be 20 30 on Fin bo 23 OLUMN-FLA eam to Colu 3x203x46 U 5x165x40 U n plate con olts, class 8.8 0 × 110 × 10 ANGE CONN umn Flange KC, S275 KB, S275 nection usi 8, M20 0thk, S275 NECTION e ng non-preeloaded Remmarks

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1. JOINT DETAILS AND SECTION OF PROPERTIES COLUMN 203x203x46 UKC, S275 Web thickness, twc 7.2 mm Flange thickness, tfc 11 mm Yield Strength, fyc 275 N/mm2 Ultimate Strength, fuc 430 N/mm2 BEAM 305x165x40 UKB, S275 Web thickness, twbl 6.0 mm Flange thickness, tfbl 10.2 mm

Yield Strength, fybl 275 N/mm2

Ultimate Strength, fubl 430 N/mm2

FIN PLATE, 230 × 110 × 10thk, S275 Depth, hp 230 mm Width, bp 110 mm Thickness, tp 10 mm Yield Strength, fyp 275 N/mm2 Ultimate Strength, fup 430 N/mm2

Direction of Load Transfer

Number of bolts row, n1 3

Plate Edge to first bolt row, e1 45 mm

Pitch between bolts row, p1 70 mm

Direction to perpendicular to load transfer

Numbers of vertical lines of bolts, n2 1

Plate Edge to first bolt line, e2 50 mm

BOLTS, NON PRELOAD, M20 CLASS 8.8 BOLTS

Gross Section of Bolts, A (un-threaded portion) 314 mm2

Tensile Stress Area, As (threaded portion) 245 mm2

Diameter of shank, d 20 mm Diameter of Holes, do 22 mm Yield Strength, fyb 640 N/mm2 Ultimate Strength, fub 800 N/mm2 FILLET WELDS Throat thk., a 5.0 mm

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2. POSITIONING OF HOLES FOR BOLTS

Minimum and maximum spacing and end and edge distance for bolts and rivets are given in Table 3.3

Minimum Maximum End distance, e1 = 1.2 do = 4tp + 40mm = 1.2 (22) = 4(10) + 40mm = 26.4mm = 80 mm Edge distance, e2 = 1.2 do = 4tp + 40mm = 1.2 (22) = 4(10)+ 40mm = 26.4mm = 80 mm Spacing, p1 = 2.2 do = smaller of 14t or 200mm = 2.2 (22) = 14 (10) = 48.4mm = 140 mm

Since - 26.4mm < 45mm < 80mm .: End distance, e1 satisfied

- 26.4mm < 50mm < 80mm .: Edge distance, e2 satisfied

- 48.4mm < 70mm < 140mm .: Spacing, p1 satisfied 3. BOLTED CONNECTION

Table 3.4

Shear Resistance Of Bolt Group Fv,Rd = (αv fub As ) / γM2

= (0.6 x 800 x 245) / 1.25 = 94.08 kN

Hence, shear resistance of bolt group, Vv,Rd

Vv,Rd = (nFv,Rd)/(√(1+αn)2+(βn)2

For a single vertical line of bolts, α = 0 and

β = 6z /n(n+1)p

1 = 6(60)/3(3+1)70 = 0.43 .: Vv,Rd = (nFv,Rd)/(√(1+αn)2+(βn)2 = (3x94.08)/(√(1+0)2+(0.43x3)2 = 172.92 kN

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Table 3.4

Table 3.4

Bearing Resistance Of Bolt Group

Fb,Rd = (k1 αb fu d tp ) / γM2 (vertical direction)

Where αb is the smallest of αd , fub/fup , 1.0

For end bolts αd = e1/3do

= 45 / 3(22) = 0.68

For inner bolts αd = (p1/3do) – (1/4)

= (70/3(22)) – (1/4) = 0.81

fub/fup = 800/430

= 1.86

.: smallest αd = αb = 0.68

And k1 for edge bolts is smallest of:

(2.8e2/d0) – 1.7) , (1.4(p2/do) – 1.7 and 2.5 (2.8e2/d0) – 1.7 = (2.8(50)/22) – 1.7 = 4.66 .: smallest k1 = 2.5 .: Fb,Rdver = (k1 αb fup d tp ) / γM2 = (2.5 x 0.68 x 430 x 20 x 10) / 1.25 = 116.96 kN Fb,Rd = (k1 αb fu d tp ) / γM2 (horizontal direction)

Where αb is the smallest of αd , fub/fup , 1.0

For end bolts αd = e2/3do

= 50 / 3(22) = 0.76 fub/fup = 800/430

= 1.86

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And k1 for edge bolts is smallest of: (2.8e1/d0) – 1.7) , (1.4(p1/do) – 1.7 and 2.5 (2.8e1/d0) – 1.7 = (2.8(45)/22) – 1.7 = 4.03 (1.4(p1/do) – 1.7 = (1.4(70/22) – 1.7 = 2.75 .: smallest k1 = 2.5 .: Fb,Rdhor = (k1 αb fup d tp ) / γM2 = (2.5 x 0.76 x 430 x 20 x 10) / 1.25 = 130.72 kN

Hence, bearing resistance of bolt group, Vb,Rd

Vb,Rd = n / √(1+αn/ Fb,Rdver)2 + (βn/ Fb,Rdhor)2

= 3 / √(1+0/ 116.96)2 + (0.43x3/130.72)2

= 229.8 kN

4. RESISTANCE OF WELDED CONNECTIONS

4.5.3.3(2) 4.5.3.3(3) 4.5.3.2(6) Table 4.1 Fw,Rd = fvwd α (eq. 4.3) fvwd = (fu/√3) / (βwγM2) (eq.4.4)

fu = nominal ultimate tensile strength of weaker part joined

= 430 N/mm2

Correlation factor, βw for fillet welds steel grade S275 = 0.85

.: fvwd = (fu/√3) / (βwγM2) = (430/√3) / (0.85 x 1.25) = 233.9 N/mm2 .: Fw,Rd = fvwd α = 233.9 N/mm2 x 5mm = 1,169.5 N/mm Weld length, L = hp - 2α = 230 mm - 10mm = 220 mm .: Vw,Rd = 1,169.5 N/mm x 220 mm x 2 = 514.58 kN

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5. BEARING RESISTANCE OF BEAM WEB

Fb,Rd = (k1 αb fubl d twbl ) / γM2 (vertical direction)

Where αb is the smallest of αd , fub/fubl , 1.0

αd = (p1/3do) – (1/4) = (70/3(22)) – (1/4) = 0.81 fub/fubl = 800/430 = 1.86 .: smallest αd = αb = 0.81

And k1 is smallest of:

(2.8e2/d0) – 1.7) , (1.4(p2/do) – 1.7 and 2.5 (2.8e2/d0) – 1.7 = (2.8(50)/22) – 1.7 = 4.66 .: smallest k1 = 2.5 Fb,Rd = (k1 αb fubl d twbl ) / γM2 = (2.5 x 0.81 x 430 x 20 x 6) / 1.25 = 83.59 kN

Fb,Rd = (k1 αb fubl d twbl ) / γM2 (horizontal direction)

Where αb is the smallest of αd , fub/fubl , 1.0

αd = e1/3do = 50 / 3(22) = 0.76 fub/fubl = 800/430 = 1.86 .: smallest αd = αb = 0.76

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And k1 is smallest of:

(1.4(p1/do) – 1.7 or 2.5

(1.4(p1/do) – 1.7 = (1.4(70/22) – 1.7

= 2.75 .: smallest k1 = 2.5

Fb,Rd = (k1 αb fubl d twbl ) / γM2 (horizontal direction)

= (2.5 x 0.76 x 430 x 20 x 6) / 1.25 = 78.43 kN

Vb,Rd = n / √(1+αn/ Fb,Rdver)2 + (βn/ Fb,Rdhor)2

= 3 / √(1+0/ 83.59)2 + (0.43x3/78.43)2

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ADDITIONAL NOTES ON SHEAR & BEARING RESISTANCE OF BOLTS GROUP

For fin plate connection, shear resistance and bearing resistance of single bolt can be determine using Table 3.4. However, to determine shear resistance and bearing resistance for bolt groups have to determine using:

Shear Resistance Of Bolts Group

V

,

nF

,

1

αn

βn

Where:

Fv,Rd = Shear resistance of single bolt from Table 3.4

n = Nos. of bolts

Bearing Resistance Of Bolts Group

V

,

n

1

αn

F

,

βn

F

, Where:

Fb,Rd = Bearing resistance of single bolt from Table 3.4

n = Nos. of bolts

For single vertical lines of bolts:

α = 0

β

6z

n n

1 p

For two vertical lines of bolts:

α

z p

2I

β

z p

2I

n

1

Where I =

p

n n

1 p

 

Figure

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