3. Steel Joint Design (Flexible End Plate)

STRUCTURAL STEELWORK & TIMBER DESIGN - ECS328 STEEL JOINT DESIGN NOV13 – MAC14

Clause

Remarks Flexible End Plate (Beam to Column Flange Connection)

Configuration Column Beam Connection End Plate

Beam to Column Flange 254 x 254 x 71 UC, S275 356 x 171 x 67 UB, S275 End Plate connection using non-preload bolts, class 8.8, M20 240 x 160 x 10mm thk., S275

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STRUCTURAL STEELWORK & TIMBER DESIGN - ECS328 STEEL JOINT DESIGN NOV13 – MAC14

Clause

1. JOINT DETAILS AND SECTION OF PROPERTIES

Remarks

COLUMN 254 X 254 X 73 kg/m UC, S275 Web thickness, twc Flange thickness, tfc Area, Ac Yield Strength, fyc Ultimate Strength, fuc

8.6 mm 14.2mm 93.1 cm2 275 N/mm2 430 N/mm2

BEAM 356 X 171 X 67 kg/m UB, S275 Web thickness, twbl Flange thickness, tfbl Area, Ab Yield Strength, fybl Ultimate Strength, fubl

9.1 mm 15.7 mm 85.5 cm2 275 N/mm2 430 N/mm2

END PLATE Plate Depth, hp Plate Width, bp Plate Thickness, tp Yield Strength, fyp Ultimate Strength, fup

240 mm 160 mm 10 mm 275 N/mm2 430 N/mm2

Direction of Load Transfer Number of bolts row, n1 Plate Edge to first bolt row, e1 Pitch between bolts row, p1 Direction to perpendicular to load transfer Numbers of vertical lines of bolts, n2 Plate Edge to first bolt line, e2 Gauge, p2 BOLTS, NON PRELOAD, M20 CLASS 8.8 BOLTS Total Numbers of Bolts, n Gross Section of Bolts, A Diameter of shank, d Diameter of Holes, do Yield Strength, fyb Ultimate Strength, fub

4 30 mm 60 mm 2 35 mm 90 mm 8 nos 314 mm2 20 mm 22 mm 640 N/mm2 800 N/mm2

FILLET WELDS Throat thk., a

4 mm

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STRUCTURAL STEELWORK & TIMBER DESIGN - ECS328 STEEL JOINT DESIGN NOV13 – MAC14

Clause 3.5(1)

2. POSITIONING OF HOLES FOR BOLTS

Remarks

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 = 1.2 (22) = 26.4mm

= 4tp + 40mm = 4(10) + 40mm = 80 mm

Edge distance, e2

= 1.2 do = 1.2 (22) = 26.4mm

= 4tp + 40mm = 4(10)+ 40mm = 80 mm

Spacing, p1

= 2.2 do = 2.2 (22) = 48.4mm

= smaller of 14t or 200mm = 14 (10) = 140 mm

Spacing, p2

= 2.4 do = 2.4 (22) = 52.8mm

= smaller of 14t or 200mm = 14 (10) = 140 mm

Table 3.3

Since - 26.4mm < 30mm < 80mm .: End distance, e1 satisfied - 26.4mm < 35mm < 80mm .: Edge distance, e2 satisfied - 48.4mm < 60mm < 140mm .: Spacing, p1 satisfied - 52.8mm < 90mm < 140mm .: Spacing, p2 satisfied Clause 

3. SHEAR & BEARING RESISTANCE OF BOLT GROUP

Remarks

Shear Resistance Table 3.4

Fv,Rd = (αv fub As ) / γM2 = (0.6 x 800 x 314) / 1.25 = 120.58kN Hence, shear resistance of bolt group, Vv,Rd Vv,Rd = Fv,Rd x n =120.58kN x 8 =964.64kN

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STRUCTURAL STEELWORK & TIMBER DESIGN - ECS328 STEEL JOINT DESIGN NOV13 – MAC14

Bearing Resistance Table 3.4

Fb,Rd = (k1 αb fu d tp ) / γM2 Where αb is the smallest of αd , fub/fup , 1.0 For end bolts αd = e1/3do = 30 / 3(22) = 0.45 For inner bolts αd = (p1/3do) – (1/4) = (60/3(22)) – (1/4) = 0.66 fub/fup = 800/430 = 1.86 .: smallest αd = αb = 0.45 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(35)/22) – 1.7 = 2.75 (1.4(p2/do) – 1.7 = (1.4(90/22) – 1.7 = 4.02 And k1 for inner bolts is smallest of: (1.4(p2/do) – 1.7 or 2.5 (1.4(p2/do) – 1.7 = (1.4(90/22) – 1.7 = 4.02 .: smallest k1 = 2.5 .: Fb,Rd = (k1 αb fup d tp ) / γM2 = (2.5 x 0.45 x 430 x 20 x 10) / 1.25 = 77.4kN Bearing Resistance of bolt Groups, Vb,Rd Vb,Rd = Fb,Rd x n =77.4 kN x 8 = 619.2 kN

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STRUCTURAL STEELWORK & TIMBER DESIGN - ECS328 STEEL JOINT DESIGN NOV13 – MAC14

Clause

4. RESISTANCE OF WELDED CONNECTIONS

4.5.3.3(2)

Fw,Rd = fvwd α (eq. 4.3)

4.5.3.3(3)

fvwd = (fu/√3) / (βwγM2) (eq.4.4)

4.5.3.2(6)

fu = nominal ultimate tensile strength of weaker part joined = 430 N/mm2

Table 4.1

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

Remarks

.: fvwd = (fu/√3) / (βwγM2) = (430/√3) / (0.85 x 1.25) = 233.9 N/mm2 .: Fw,Rd = fvwd α = 233.9 N/mm2 x 4mm = 935.6 N/mm Weld length, L = hp - 2α = 240 mm - 8mm = 232 mm .: Vw,Rd = 935.6 N/mm x 232 mm x 2 = 434.11 kN Clause 6.2.6(2) (EC3-1)

5. SHEAR RESISTANCE OF BEAM WEB

Remarks

Vpl, Rd = Av (fyp/√3) /γMo Beam Web Av web = 0.9 L twbl = 0.9 x 240 x 9.1 = 1965.6 mm2 Vbl, Rd = Av (fyp/√3) /γMo = (1965.6)(275/√3) / 1.0 = 312.45 kN

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STRUCTURAL STEELWORK & TIMBER DESIGN - ECS328 STEEL JOINT DESIGN NOV13 – MAC14

Clause 6.2.6(2) (EC3-1)

6. SHEAR RESISTANCE OF END PLATE

Remarks

Vpl, Rd = Av (fyp/√3) /γMo Gross Section Av = hp tp/1.27 = 240(10) / 1.27 = 1889.76 mm2 Vpl, Rd = Av (fyp/√3) /γMo = (1889.76)(275/√3) / 1.0 = 300.04 kN Consider for 2 plates .: Vpl, Rd = 300.04 kN x 2 = 600.08 kN Net Section Avnet = tp (hp – n1do) = 10 (240 – (4x22)) = 1520 mm2 Vnet, Rd = Av (fup/√3) /γM2 = (1520)(430/√3) / 1.25 = 301.9 kN Consider for 2 plates .: Vnet, Rd = 301.9kN x 2 = 603.8 kN

Clause 3.10.2(2)

7. BLOCK TEARING

Remarks

Symmetric bolt group subject to concentrate loading, design block tearing resistance: Veff,1,Rd = fup Ant /γM2 + (1/√3)fyp Anv/ γM0 (eq. 3.9) Ant = (p2 - do)tp = (90 -22)10 = 680 mm2 Anv = 2(hp – e1 – (n1-0.5)do) tp = 2(240 – 30 – 3.5(22))10 = 2660 mm2 .: Veff,1,Rd = fup Ant /γM2 + (1/√3)fyp Anv/ γM0 = (430 x 680)/1.10 + ((1/√3)(275 x 2660))/1.0 = 675.8 kN

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