Lifting Lug Calculation

RIVELIN CONSULTANTS LIMITED

CLIENT UNITED ENGINEERING SERVICES LTD. Date 9-May-11

PROJECT PETROTRIN Precast concrete foundation pads By M Rampersad

Location Lifting lug design checks Job Ref 241-002

Sub-Location Pipe Supports Page

REF OUTPUT

References

1. Client Drawing DET-1

2. AISC 360-05 Specification for structural steel buildings

3. AISC LRFD Manual 1999

4. DNV 2.7-1 Std. for Certification, Offshore containers

5. Load analysis from Client

6. W-shapes dimensions to ASTM A6M

Padeye dimensions:

Min distance from pinhole to edge, y-direction, a = 76.2 mm

Min distance from pinhole to edge, x-direction, b = 56.1 mmPinhole diameter, dh = 50.8 mm

Pin diameter, dpin = 48.3 mm

Padeye plate thickness, t = 20.0 mm

Padeye width, w = 165.0 mmPadeye effective outer distance, ro = 101.6 mm

Cheek plate diameter, dc = 50.8 mm

Cheek plate thickness, tc = mm

Distance from fixed edge to pinhole centre, h1 = 152.4 mm

Loading:

DESCRIPTION

Loading:

Ref 5 Angle θ = 90.0 deg

Angle θ = 1.571 radSling force RS = 45.0 kN

Horizontal component (x-direction) RSx = 0.1 kN

Vertical component (y-direction) RSy = 45.0 kN

h1=153

w=165

dc=51

dpin=49

dh=51

a=77

r0=102

b=57

t=20

tc=0

Rs=45 kN

Rsx=0.1 kN

Rsy=45 kN

6mm‐E60 xx

dc=51

dpin=49






REF OUTPUTDESCRIPTION

Padeye material

Select grade of padeye steel A36Yield strength, Fy 245.0 N/mm2

Ultimate tensile strength, Fu 400.0 N/mm2

GEOMETRIC CHECKS

b eff = 2t+16mm ≤b

2t+16= 56.0 mmCheck for beff < b OK

w ≥ 2b eff + d

2b eff + d = 162.8 mm

Check forw ≥ 2b eff + d OK

a ≥ 1.33b eff

1.33b eff = 74.5 mm

Check for a ≥ 1.33b eff OK

CODE CHECKSTension on Net effective area

General formulaEqn D3-1 P = 2tb F

Ref 3 Clause D3-1b

Ref 2, Clause C-D5

Ref 3 Clause D3-1b

Ref 3 Clause D3-1a (a)

Eqn D3-1 P n = 2tb eff F u

2tb eff F u = 896.0 kN

Design strength in tension = ØPn

Ø = 0.75 [unitless] Design strength in tension, ØPn = 672.0 kN

Check against Rs 45.0 kN OK with Rs in tension

Check against Rsx 0.1 kN OK with Rsx in tension

Check against Rsy 45.0 kN OK with Rsy in tension

Shear on the effective area

General formulaEqn D3-2 P n = 0.6A sf F u

Design strength in shear = ØPn

Ø = 0.75 [unitless]

y-axis x-axis

Ref 3 Clause D3-1a (b)

y

a+dh/2 b+dh/2

x







Check shear due to R sy

For the R sy component, A sf = 2 [t(a+d h /2) + 2yt c ] = 4064.0 mm2

where y = √[(d c2 -d h

2) /4] = mm

P ny = 0.6A sf F u = 975.4 kN

ØPny = 731.5 kN

Check against actual Rsy 45.0 kN OK with Rsy in shear

Check shear due to R sx

For the R sx component, A sf = 2 [t(b+d h /2) + 2xt c ] = 3260.0 mm2

where x = √[(d c2 -(d h

2 /2)] = 44.0 mm

P nx = 0.6A sf F u = 782.4 kN

ØPnx = 586.8 kN

Check against actual Rsx 45.0 kN OK with Rsx in shear

Bearing on projected pin area

General formula (assuming milled, drilled, reamed or bored holes)Eqn J8-1 R n = 1.8F y A pb

Design strength in bearing = ØRn

Ø = 0.75 [unitless]

Ref 3 Clause J8 (a)

Check bearing (both axes are the same)Projected bearing area (same either axis), A pb = d pin (t+2t c ) = 965.2 mm2

1.8F y A pb = 425.7 kN

Design strength in bearing, ØRn = 319.2 kN

Check against Rsx 0.1 kN OK with Rsx in bearing

Check against Rsy 45.0 kN OK with Rsy in bearing

Yield in gross section

General formulaEqn D1-1 P n = F y A g

Where A g = Gross cross-sectional area through padeye in the direction of the force

Design strength in yield = ØtPn

Øt = 0.90 [unitless]

y-axis x-axis

Ref 3 Clause D1 (a)







Check gross tension due to R sy

A gy = 2(tb+2t c [(d c -d h )/2]) 1122.0 mm2

P ny = F y A gy = 274.9 kN

Design strength in yield, ØtPny = 247.4 kN

Check against R 45 0 kN OK ith R i i ld

y-axis x-axis

Check against Rsy 45.0 kN OK with Rsy in yield

Check gross tension due to R sx

A gx = at+(h 1 t-d h /2)+2t c [(d c -d h )/2]) 4546.6 mm2

P nx = F y A gx = 1113.9 kN

Design strength in yield, ØtPnx = 1002.5 kN

Check against Rsx 45.0 kN OK with Rsx in bearing

BENDING CHECKSBending due to R sx (about Z-Z axis)

Lever arm to Rsx component, h1 = 152.4 mm

Moment Mx = 15,240 Nmm

Moment of inertia for padeye (bd3/12), Izz = 7,486,875 mm4

Bending stress, δ = 0.2 N/mm2OK in bending about zz axis

WELDING CHECKS

Select welding electrode strength 60,000 ksi design strength of fillet weld, pw = 414 N/mm2

Select nominal fillet weld size, a = 6 mm

Use the directional method as per BS5950 Cl 6.8.7.3Check longitudinal weld shear capacity P L (in direction of x-axis)

P L = p w a

Longitudinal weld capacity per unit length, P L = 2484.0 N/mm

Total length of weld, 2w = 330.0 mm Total longitudinal weld shear capacity, P L = 819.7 kN

Check against R sx = 0.1 kN Weld OK in longitudinal shear







Check transverse weld shear capacity P T (in direction of y-axis)

P T = KP L

K = 1.25 √[1.5/(1+cos 2 β)]

β = angle between vertical and throat of weld = 45 deg β = 0.785 rad

K = 1.25 [unitless]Transverse weld capacity per unit length, P T = 3105.0 N/mm

Total length of weld, 2w = 330.0 mm Total transverse weld shear capacity, P T = 1024.7 kN

Check against R sy = 45.0 kN Weld OK in transverse capacity

Unity check on transverse and longitudinal capacity(R SX /P L ) 2 +(R SY /P T ) 2 ≤1

(R SX /P L ) 2 = 0.000 [unitless]

(R SY /P T ) 2 = 0.002 [unitless](R SX /P L ) 2 +(R SY /P T ) = 0.002 [unitless] Unity check on weld OK

ADDITIONAL CODE CHECKS TO DNV 2.7-1 (if required)Tear-out stress

General formula from DNVR e ≥ 3R SL /(2Ht-d h t) *

U i thi l l ti t i l

Ref 4 Appx D3

Using this calculation terminologyDNV Code [R e ] = min. yield stress of padeye material = [F y ] this calculation

DNV code [RSL] = sling load (factored) = [Rs] this calculationDNV code [H] = centre of hole to min. outer edge = [r 0 ] this calculation

Fy ≥ 3RS/(2r0t-dht)

3RS/(2r0t-dht) = 44.3 N/mm2

F y = 245.0 N/mm2OK in DNV tear-out stress

* Note: cheek thickness not allowed by DNV 2.7-1 as part of this calculation

Contact stress

General formula from DNVR e ≥ 23.7 √(R SL /d h t)

Using this calculation terminology as above

Fy ≥ 23.7√(RS/dh[t+2tc])

23.7√(RS/dh[t+tc]) = 157.7 N/mm2

F y = 245.0 N/mm2OK in DNV contact stress

Shackle pin diameter

General formula from DNVd pin ≥ 94% d h

dpin = 48.3 mm

0.94dh = 47.8 mm OK in DNV pin diameter

Total thickness at contact area is (padeye thickness + 2Xcheek thickness)

Ref 4 Clause 4.4.1

Ref 4 Appx D3

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Lifting Lug Calculation