07 manus 12 bolted joints 09
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Wardenier RHS Joints - Oslo Course 2009
Bolted Joints between Hollow Sections
Prof.dr.ir. Jaap Wardenier
Em. Delft University of Technology
Wardenier RHS Joints - Oslo Course 2009
Types of Bolted JointsTypes of Bolted Joints
1. Joints with Bolts in Shear
2. Joints with Bolts in Tension
Bolted hollow section joints can typically be classified
into two groups, depending on how the bolts are loaded:
Wardenier RHS Joints - Oslo Course 2009
Splice Joints with Bolts in ShearSplice Joints with Bolts in Shear
Interior/Exterior Splice Plates for large RHS
Wardenier RHS Joints - Oslo Course 2009
Splice Joints with Bolts in ShearSplice Joints with Bolts in Shear
Gussets with External Splice Bars permits sealing with cap plates
Wardenier RHS Joints - Oslo Course 2009
Diagonal Bracings in a Braced-Frame
Slotted plates welded into the ends of a RHS diagonal bracing
Wardenier RHS Joints - Oslo Course 2009
Slotted Gusset Plates into Truss Members
Slotted plate into a CHS member, with the gusset plate tapered for aesthetic appeal
Wardenier RHS Joints - Oslo Course 2009
Some bolted Joints
Wardenier RHS Joints - Oslo Course 2009
Bolted Joints with Bolts in Shear
Wardenier RHS Joints - Oslo Course 2009
Bolted Joints for Truss Supports
Wardenier RHS Joints - Oslo Course 2009
Double Channel
Beams
Bolted to Plates
on
RHS Column
Faces
Wardenier RHS Joints - Oslo Course 2009
Bolted Joints with Bolts in Shear
Wardenier RHS Joints - Oslo Course 2009
Bolted Gusset-Plate Joints to RHS
Limitation:
Member widths must be closely matched.
Potential Problem:
Welding contraction tends to pull the gussets inwards. The gussets may need to be spread slightly by jacking after welding.
Wardenier RHS Joints - Oslo Course 2009
Bolted Gusset-Plate to RHS Joints
Design needs to consider potential failure modes:
1. Shear failure of bolts
2. Bolt bearing: On the hollow section and on the gusset plate
3. Yielding or buckling of the gusset plate, using the Whitmore
criterion
4. Tear Out of the gusset plate (tension only) – All possible failure paths
5. Tear Out of the hollow section (Member tension load only)
– Examine all possible failure paths
Wardenier RHS Joints - Oslo Course 2009
Bolted Gusset-Plate to RHS Joints
3. Yielding or buckling of the gusset plate, using the Whitmore
criterion
If load is compression; buckling
capacity is based on a column of
width (g + 1.15 ∑ p), depth of tp ,
a length equal to the minimum of
L1, L2 and L3 and an effective
length factor of 0.65.
Wardenier RHS Joints - Oslo Course 2009
Bolted fin plate Joint
Wardenier RHS Joints - Oslo Course 2009
Fin plate (or shear tap) Joints
y,c0
0
f
E114.0
t
d≤
y,c0
0
f
E4.1
t
b≤
Avoid
too much
distortion
of the
column face:A
Section A-A
A
Wardenier RHS Joints - Oslo Course 2009
Fin plate Joint
Check for:
a.beam web failure
b.bolt shear failure
c.bolt bearing failure
d.plate failure
e.weld failure
f. column punching shear failure
g.column face plastification
(only for horizontal loads)
b, e and f should not be governing!
A
Section A-A
A
Wardenier RHS Joints - Oslo Course 2009
Fin plate Joint
Avoid:
b. bolt shear failure → stronger than other criteria
e. weld failure → 2a.fs,weld > tp.(0.58 fp,y)
f. column punching shear failure
→ 2 tc.(0.58 fc,y) > tp.(0.58 fp,y )
b, e and f should not be governing!
A
Section A-A
A
Wardenier RHS Joints - Oslo Course 2009
Fin plate Joint
d. Plate failure
65
65
65 65
70
70
70
(a) (b)
Tensile Rupture
ShearRupture
ShearRupture
A
Section A-A
A
Wardenier RHS Joints - Oslo Course 2009
Other Plate and T stub Joints
D
Section D-D
DE
Section E-E
E B
Section B-B
B
Wardenier RHS Joints - Oslo Course 2009
Bolted Joints to diaphragm plates
Wardenier RHS Joints - Oslo Course 2009
Bracing Joints (see welded plate to RHS connections)
∆
θ
hp
bp
hc
tc
bc
h 'p
w
Np
β = b / bp c
β' = (b + 2w) / (b - t )p c c
b ' = b - tc c c
Wardenier RHS Joints - Oslo Course 2009
Bolted Joints
Wardenier RHS Joints - Oslo Course 2009
PRYING FORCES develop when flange-plates lever against each other.
⇒ Prying forces increase the load in the bolts
⇒ Early failure of the connection
Joints with Bolts in Tension
N N
B =N
2B =
N
2
Q Q
B =N
2+ Q B =
N
2+ Q
Wardenier RHS Joints - Oslo Course 2009
Bolted Flange-Plate to RHS Joints
With bolts along 2 sides of the hollow section
Connection behaviour is
representative of
2-dimensional prying
models
Wardenier RHS Joints - Oslo Course 2009
Bolted Joints
Yield lines at distance
b’=b-d/2+ti
Wardenier RHS Joints - Oslo Course 2009
Bolted End Joints at 4 sides
If no prying:
1u
m
12pyp bB
1ptf
4
1⋅=
γ⋅⋅⋅⋅
Modified AISC:
Yield lines along
outer sides RHS
Use p or p’ (minimum)
bb11
Wardenier RHS Joints - Oslo Course 2009
Single sided bolted Joint
Wardenier RHS Joints - Oslo Course 2009
Wall Thickening
Wardenier RHS Joints - Oslo Course 2009
Single sided bolting
1.1. LindapterLindapter HolloBoltHolloBolt
2.2. Huck UltraHuck Ultra--twisttwist
3.3. FlowdrillFlowdrill
4.4. OthersOthers
1.
Wardenier RHS Joints - Oslo Course 2009
2. Huck
Ultra-Twist
Wardenier RHS Joints - Oslo Course 2009
Column Joints Using Huck Ultratwist FastenersColumn Joints Using Huck Ultratwist Fasteners
Column splice
Beam-to-column end-plate
connection
Wardenier RHS Joints - Oslo Course 2009
One-Sided Bolting using FlowdrillOne-Sided Bolting using Flowdrill
- The Flowdrill extrudes a precision hole in the hollow section, with 80% of the molten displaced material flowing down and 20% up.
- This forms a boss of 3 times the hollow section thickness, which can then be threaded with a Flowtap.
- Conventional bolts can then be screwed into the holes from one side.
- Less tolerance for field bolting relative to conventional bolt holes.
www.flowdrill.nl
Wardenier RHS Joints - Oslo Course 2009
Flow drill blind bolted joints
Up to 12.5 mm
Wardenier RHS Joints - Oslo Course 2009
Other Methods: Welded Threaded Studs
Wardenier RHS Joints - Oslo Course 2009
Other Methods: Welded Nuts
Wardenier RHS Joints - Oslo Course 2009
Design Recommendations
Wardenier RHS Joints - Oslo Course 2009
Design Recommendations
Simulate as standard RHS-RHS T-joint, with outer bolt
centres as the RHS bracing corners, with a reduction for
the bolt holes
Wardenier RHS Joints - Oslo Course 2009
Example: Cast steel node for space frames
This one not produced anymore
Wardenier RHS Joints - Oslo Course 2009
Nails in Shear
Powder–activated fasteners, or "nails", can be used as structural
connectors for mating circular hollow sections
Ideal for poles – especially in remote locations
Wardenier RHS Joints - Oslo Course 2009
Joint design is based on classic failure modes
for bolted joints:
1. Shear failure
of fasteners
2. Fastener bearing
on the base metal3. Net section fracture of
the tube cross section
Wardenier RHS Joints - Oslo Course 2009
The end of the
lectures on
Bolted Joints
Do not stiffen
in this wrong way!!!
Do not stiffen
in this wrong way!!!
Wardenier RHS Joints - Oslo Course 2009
Bolted Gusset-Plate to RHS Joints
4. Tear Out of the gusset plate (tension only) – All possible failure paths
Gusset Tear to
Edge of Plate
Wardenier RHS Joints - Oslo Course 2009
4. Tear Out of the brace – All possible failure paths
Bolt
Pattern
Tear out
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