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Su2016abnSteel Bolts & Welding 1
Lecture 18
Architectural Structures
ARCH 331
lecture
eighteen
steel construction:
bolts, welds & light gagesnrmc.org
ARCHITECTURAL STRUCTURES:
FORM, BEHAVIOR, AND DESIGN
ARCH 331
DR. ANNE NICHOLS
SUMMER 2016
Su2016abnSteel Bolts & Welding 2
Lecture 18
Architectural Structures
ARCH 331
Connections
• needed to:
– support beams by columns
– connect truss members
– splice beams or columns
• transfer load
• subjected to
– tension or compression
– shear
– bending
Su2016abnSteel Bolts & Welding 3
Lecture 18
Architectural Structures
ARCH 331
Bolts
• bolted steel connections
(AISC - Steel Structures of the Everyday)
http://courses.civil.ualberta.ca
Su2016abnSteel Bolts & Welding 4
Lecture 18
Architectural Structures
ARCH 331
Welds
• welded steel connections
http://courses.civil.ualberta.ca
Su2016abnSteel Bolts & Welding 5
Lecture 18
Architectural Structures
ARCH 331
Bolts
• types
– materials
• high strength
• A307, A325, A490
– location of threads
• included - N
• excluded - X
– friction or bearing (SC)
• always tightened
Su2016abnSteel Bolts & Welding 6
Lecture 18
Architectural Structures
ARCH 331
Bolted Connection Design
• considerations
– bearing stress
• yielding
– shear stress
• single & double
– member
• rupture
Su2016abnSteel Bolts & Welding 7
Lecture 18
Architectural Structures
ARCH 331
Bolts
• rarely fail in bearing
• holes considered 1/8” larger
• shear & tension
– single shear or tension
– double shear
75.0v
bnn AFR
bnn AFR 2
nvu RR n
a
RR
Su2016abn
Bolts
Steel Bolts & Welding 8
Lecture 18
Architectural Structures
ARCH 331
http://www.fastenal.com
Su2016abnSteel Bolts & Welding 9
Lecture 18
Architectural Structures
ARCH 331
Bolts
• bearing
– deformation is concern
– deformation isn’t concern
– long slotted holes
Lc – clear length to edge or next hole (ex. 1¼”, 3”)
75.0
uucn dtF.tFL.R 4221
nu RR
uucn dtF.tFL.R 0351
uucn dtF.tFL.R 0201
n
a
RR
Su2016abn
Bolts
Steel Bolts & Welding 10
Lecture 18
Architectural Structures
ARCH 331
A490, A490M
F2280
A354 Grade BD
Su2016abnSteel Bolts & Welding 11
Lecture 18
Architectural Structures
ARCH 331
Welded Connection Design
• considerations
– shear stress
– yielding
– rupture
Su2016abnSteel Bolts & Welding 12
Lecture 18
Architectural Structures
ARCH 331
Welded Connection Design
• weld terms
– butt weld
– fillet weld
– plug weld
– throat
• field welding
• shop welding
(AISC - Steel Structures of the Everyday)
Su2016abnSteel Bolts & Welding 13
Lecture 18
Architectural Structures
ARCH 331
Welded Connection Design
• weld process
– melting of material
– melted filler - electrode
– shielding gas / flux
– potential defects
• weld materials
– E60XX
– E70XX
FEXX = 70 ksi
Su2016abnSteel Bolts & Welding 14
Lecture 18
Architectural Structures
ARCH 331
Welded Connection Design
• shear failure assumed
• throat
– T = 0.707 x weld size
• area
– A = T x length of weld
• weld metal generally stronger than base metal (ex. Fy = 50 ksi)
Su2016abnSteel Bolts & Welding 15
Lecture 18
Architectural Structures
ARCH 331
Welded Connection Design
• minimum
– table
• maximum
– material thickness ( to ¼”)
– 1/16” less
• min. length
– 4 x size min.
– ≥ 1 ½”
16316
58
316
78
5
Su2016abnSteel Bolts & Welding 16
Lecture 18
Architectural Structures
ARCH 331
Welded Connection Design
• shear
– table for S
area
n
a
RR
nu RR 75.0
SlTlF.R EXXn 60
Su2016abnSteel Bolts & Welding 17
Lecture 18
Architectural Structures
ARCH 331
Framed Beam Connections
• angles
– bolted
– welded
Su2016abnSteel Bolts & Welding 18
Lecture 18
Architectural Structures
ARCH 331
Framed Beam Connections
• terms
– coping
(AISC - Steel Structures of the Everyday)
Su2016abnSteel Bolts & Welding 19
Lecture 18
Architectural Structures
ARCH 331
Framed Beam Connections
• tables for standard
bolt sizes & spacings
• # bolts
• bolt diameter, angle
leg thickness
• bearing on
beam web
Su2016abnSteel Bolts & Welding 20
Lecture 18
Architectural Structures
ARCH 331
Framed Beam Connections
• welded example (shear)
(AISC - Steel Structures of the Everyday)
Su2016abnSteel Bolts & Welding 21
Lecture 18
Architectural Structures
ARCH 331
Framed Beam Connections
• welded moment example
(AISC - Steel Structures of the Everyday)
Su2016abnSteel Bolts & Welding 22
Lecture 18
Architectural Structures
ARCH 331
Framed Beam Connections
• welded/bolted moment example
(AISC - Steel Structures of the Everyday)
Su2016abnSteel Bolts & Welding 23
Lecture 18
Architectural Structures
ARCH 331
Framed Beam Connections
• welded/bolted moment example
(AISC - Steel Structures of the Everyday)
Su2016abnSteel Bolts & Welding 24
Lecture 18
Architectural Structures
ARCH 331
Beam Connections
• LRFD provisions
– shear yielding
– shear rupture
– block shear rupture
– tension yielding
– tension rupture
– local web buckling
– lateral torsional buckling
Su2016abnSteel Bolts & Welding 25
Lecture 18
Architectural Structures
ARCH 331
– where Ubs is 1 for uniform tensile stress
75.0
block shear rupture tension rupture
ntubsgvyn tubsnvun AFUAF.AFUAF.R 6060
Beam Connections
Su2016abnSteel Bolts & Welding 26
Lecture 18
Architectural Structures
ARCH 331
Other Connections
• seated beam
• continuous
– beam to column
– beam to beam
Su2016abnSteel Bolts & Welding 27
Lecture 18
Architectural Structures
ARCH 331
Other Connections
• splices
The Royal Ontario Museum Toronto . CanadaDaniel Libeskind
(AISC - Steel Structures of the Everyday)
http://courses.civil.ualberta.ca
Su2016abnSteel Bolts & Welding 28
Lecture 18
Architectural Structures
ARCH 331
Other Connections
• rigid frame knees
• gussets & joints
(AISC - Steel Structures of the Everyday)
Su2016abnSteel Bolts & Welding 29
Lecture 18
Architectural Structures
ARCH 331
Other Connections
• base plates
– anchor bolts
– bearing on steel
– bending of platehttp://courses.civil.ualberta.ca