Post on 03-May-2018
S2018abnSteel Bolts & Welding 1
Lecture 21
Architectural Structures
ARCH 331
ARCHITECTURAL STRUCTURES:
FORM, BEHAVIOR, AND DESIGN
ARCH 331
DR. ANNE NICHOLS
SPRING 2018
lecture
twenty one
steel construction:
bolted & welded connectionsnrmc.org
S2018abnSteel Bolts & Welding 2
Lecture 21
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
S2018abnSteel Bolts & Welding 3
Lecture 21
Architectural Structures
ARCH 331
Bolts
• bolted steel connections
(AISC - Steel Structures of the Everyday)
http://courses.civil.ualberta.ca
S2018abnSteel Bolts & Welding 4
Lecture 21
Architectural Structures
ARCH 331
Welds
• welded steel connections
http://courses.civil.ualberta.ca
S2018abnSteel Bolts & Welding 5
Lecture 21
Architectural Structures
ARCH 331
Bolts
• types
– materials
• high strength
• A307, A325, A490
– location of threads
• included - N
• excluded - X
– bearing or friction (SC)
• always tightened
S2018abnSteel Bolts & Welding 6
Lecture 21
Architectural Structures
ARCH 331
Bolted Connection Design
• considerations
– bearing stress
• yielding
– shear stress
• single & double
– member
• rupture
S2018abnSteel Bolts & Welding 7
Lecture 21
Architectural Structures
ARCH 331
Bolts
• rarely fail in bearing
• holes considered 1/8” larger
• shear & tension
– single shear or tension
– double shear
7 5.0v
bnn AFR
bnn AFR 2
nvu RR
na
RR
S2018abn
Bolts
Steel Bolts & Welding 8
Lecture 21
Architectural Structures
ARCH 331
http://www.fastenal.com
S2018abnSteel Bolts & Welding 9
Lecture 21
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”)
7 5.0
uucn d t F.t FL.R 4221
nu RR
uucn d t F.t FL.R 0351
uucn d t F.t FL.R 0201
n
a
RR
S2018abnSteel Bolts & Welding 11
Lecture 21
Architectural Structures
ARCH 331
Welded Connection Design
• considerations
– shear stress
– yielding
– rupture
S2018abnSteel Bolts & Welding 12
Lecture 21
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)
S2018abnSteel Bolts & Welding 13
Lecture 21
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
S2018abnSteel Bolts & Welding 14
Lecture 21
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)
S2018abnSteel Bolts & Welding 15
Lecture 21
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
S2018abn
• shear
– table for S
Steel Bolts & Welding 16
Lecture 21
Architectural Structures
ARCH 331
Welded Connection Design
area
n
a
RR
nu RR 7 5.0
S lT lF.R E X Xn 60
S2018abnSteel Bolts & Welding 17
Lecture 21
Architectural Structures
ARCH 331
Framed Beam Connections
• angles
– bolted
– welded
S2018abnSteel Bolts & Welding 18
Lecture 21
Architectural Structures
ARCH 331
Framed Beam Connections
• terms
– coping
(AISC - Steel Structures of the Everyday)
S2018abnSteel Bolts & Welding 19
Lecture 21
Architectural Structures
ARCH 331
Framed Beam Connections
• tables for standard
bolt sizes & spacings
• # bolts
• bolt diameter, angle
leg thickness
• bearing on
beam web
S2018abnSteel Bolts & Welding 20
Lecture 21
Architectural Structures
ARCH 331
Framed Beam Connections
• welded example (shear)
(AISC - Steel Structures of the Everyday)
S2018abnSteel Bolts & Welding 21
Lecture 21
Architectural Structures
ARCH 331
Framed Beam Connections
• welded moment example
(AISC - Steel Structures of the Everyday)
S2018abnSteel Bolts & Welding 22
Lecture 21
Architectural Structures
ARCH 331
Framed Beam Connections
• welded/bolted moment example
(AISC - Steel Structures of the Everyday)
S2018abnSteel Bolts & Welding 23
Lecture 21
Architectural Structures
ARCH 331
Framed Beam Connections
• welded/bolted moment example
(AISC - Steel Structures of the Everyday)
S2018abnSteel Bolts & Welding 24
Lecture 21
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
S2018abnSteel Bolts & Welding 25
Lecture 21
Architectural Structures
ARCH 331
– where Ubs is 1 for uniform tensile stress
7 5.0
block shear rupture tension rupture
n tub sg vyn tub sn vun AFUAF.AFUAF.R 6060
Beam Connections
S2018abnSteel Bolts & Welding 26
Lecture 21
Architectural Structures
ARCH 331
Other Connections
• seated beam
• continuous
– beam to column
– beam to beam
S2018abnSteel Bolts & Welding 27
Lecture 21
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
S2018abnSteel Bolts & Welding 28
Lecture 21
Architectural Structures
ARCH 331
Other Connections
• rigid frame knees
• gussets & joints
(AISC - Steel Structures of the Everyday)