Lap shear bolted plates

12
Bolt failure study in a heavy steel plate lap shear joint 10/12/17 rev A Don Blanchet 3B Associates [email protected] 15” x 10” x 1” plates lap shear ¾ UNC-10 – 8 places Prepared for CBL construction Vitoria , Brazil

Transcript of Lap shear bolted plates

Page 1: Lap shear bolted plates

Bolt failure study in a heavy steel plate lap shear joint

10/12/17 rev A

Don Blanchet

3B Associates

[email protected]

15” x 10” x 1” plates lap shear

¾ UNC-10 – 8 placesPrepared forCBL constructionVitoria , Brazil

Page 2: Lap shear bolted plates

Lift Rigging Safety

Page 3: Lap shear bolted plates

Goals

Evaluate the grade 5 ¾ inch bolts that are in use.

Demonstrate sequential bolt failure.

Set the maximum load capacity.

Heavy lift rigging fixture application factor of safety.

Page 4: Lap shear bolted plates

Bolt Torque

Page 5: Lap shear bolted plates

Results 8 bolts 2 failures

Page 6: Lap shear bolted plates

Results: 8 bolts 2 failures

Fixed endwelded

Load applied6000 lbs

Page 7: Lap shear bolted plates

Results 6 bolts 4 failures

Page 8: Lap shear bolted plates

Results: 6 bolts 4 failures

Fixed endwelded

Load applied6000 lbs

With a 3 ton load , the assembly will fail completely In sequence 2-bolts, 4-bolts, 2-bolts

Page 9: Lap shear bolted plates

Bolt Safe loading – 1.5 Tons

Page 10: Lap shear bolted plates

Bolts factor of safety 1.2or 20% margin of safety

Page 11: Lap shear bolted plates

Max stress in platesfactor of safety = 2.6

Page 12: Lap shear bolted plates

Recommendations

Stamp plates with “max load 1.5 tons”

Change from grade 5 to Grade 8 bolts