Yu W., LaBoube R.A. Cold-Formed Steel Design
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NOMENCLATURE 405
K
effi,j
Effective lateral stiffness of j th anchorage
device with respect to i th purlin
K
req
Required stiffness
K
sys
Lateral stiffness of roof system, neglecting
anchorage device
K
t
Effective length factor for torsion
K
total,i
Effective lateral stiffness of all elements
resisting force P
i
K
x
Effective length factor for bending about
x axis
K
y
Effective length factor for bending about
y axis
k Buckling coefficient
k
a
Plate buckling coefficient
k
d
Plate buckling coefficient for distortional
buckling
k
loc
Plate buckling coefficient for local
subelement buckling
k
u
Plate buckling coefficient
k
v
Shear buckling coefficient
k
F
Rotational stiffness
k
Ffe
Elastic rotational stiffness provided by
flange to flange–web juncture
˜
k
φfg
Geometric rotational stiffness demanded by
flange from flange/web juncture
k
Fwe
Elastic rotational stiffness provided by web
to flange–web juncture
˜
k
φwg
Geometric rotational stiffness demanded by
web from flange–web juncture
L Full span for simple beams
Distance between inflection points for
continuous beams
Twice length of cantilever beams
Unbraced length of member
Length of stud
Length of element
Length of seam weld not including circular
ends
Length of fillet weld
Live load
Minimum of L
cr
and L
m
L
b
Actual unbraced length in plane of bending
Length of beam
L
br
Unsupported length between braced points
or other restraints which restrict distortional
buckling of element
L
c
Length of column
Length of corner
L
cr
Critical unbraced length of distortional
buckling
L
f
Flat width of flange
L
h
Length of hole
L
m
Distance between discrete restraints that
restrict distortional buckling
L
o
Overhang length measured from edge of
bearing to end of member
L
r
Roof live load
L
s
Length of portion of span between supports
where flange that is not connected to
sheating is in compression
L
st
Total length of bearing stiffener
L
t
Unbraced length of compression member
for torsion
L
u
Critical unbraced length for
lateral–torsional buckling
L
w
Flat width of web
L
x
Unbraced length of compression member
for bending about x axis
L
y
Unbraced length of compression member
for bending about y axis
L
0
Length at which local buckling stress
equals flexural buckling stress
l Distance from concentrated load to a brace
l
i
Length of middle line of segment i
M Bending moment
Required flexural strength for ASD
Applied bending moment at or immediately
adjacent to point of application of
concentrated load or reaction P
Material factor
M
A
Absolute value of moment at quarter point
of unbraced segment for determining C
b
M
a
Allowable bending moment permitted if
bending stress only exists
Allowable flexural strength
M
ax
,M
ay
Allowable moments about centroidal axes
M
allow
Allowable bending moment permitted if
bending stress only exists
M
B
Absolute value of moment at centerline of
unbraced segment for determining C
b
M
C
Absolute value of moment at three-quarter
point of unbraced segment for
determining C
b
Elastic critical moment causing
compression on shear center side of
centroid
M
c
Critical moment
M
cr
Critical moment
M
crd
Distortional buckling moment
M
cre
Overall buckling moment
M
crl
Local buckling moment
M
D
Bending moment due to dead load
M
d
Nominal moment with consideration of
deflection
406 NOMENCLATURE
M
e
Elastic critical moment
M
f
Factored moment
M
fx
,M
fy
Moments due to factored loads with respect
to centroidal axes for LSD
M
L
Bending moment due to live load
M
m
Mean value of tested material properties to
minimum specified values
M
max
Absolute value of maximum moment in
unbraced segment for determining C
b
M
n
Nominal flexural strength
Nominal moment
Ultimate moment causing maximum
compression strain of C
y
ε
y
M
nd
Nominal flexural strength for distortional
buckling
M
ne
Nominal flexural strength for overall
buckling
M
nl
Nominal flexural strength for local buckling
M
no
Nominal yield moment for nested
Z-sections
M
nx
Nominal flexural strength about x axis
M
ny
Nominal flexural strength about y axis
M
nxo
Nominal flexural strength about x axis
determined only for section strength
M
nyo
Nominal flexural strength about y axis
determined only for section strength
M
nxt
Nominal flexural strength about x axis
determined using gross, unreduced
cross-sectional properties
M
nyt
Nominal flexural strength about y axis
determined using gross, unreduced
cross-sectional properties
M
p
Full plastic moment
M
T
Elastic critical moment causing tension on
shear center side of centroid
M
t
Torsional moment
M
u
Required flexural strength
M
ux
Required flexural strength about x axis for
LRFD
M
uy
Required flexural strength about y axis for
LRFD
M
x
Bending moment about x axis
M
y
Yield moment
Bending moment about y axis
M Required flexural strength (factored
moment)
M
x
, M
y
Required flexural strengths (factored
moments)
M
z
Torsional moment of required load P about
shear center
M
0
Maximum moment between supports due to
transverse loading
M
1
Smaller end moment
M
2
Larger end moment
Mn Manganese content
m Term for determining tensile yield stress of
corners
Distance from shear center of one C-section
to midplane of web
Number of half sine waves
m
f
Modification factor for type of bearing
connection
N Actual length of bearing
Tensile strength of spot welding
N
a
Number of anchorage devices along line of
anchorage
N
i
Notional lateral load applied at level i
N
p
Number of purlin lines on roof slope
N
∗
N /t ratio
n Number of half sine waves
Number of holes
Number of anchors in test assembly or
number of panels
Number of stiffeners
Number of equally spaced intermediate
brace locations
Number of threads per inch
n
b
Number of bolt holes
n
h
Number of holes in critical plane
P Applied axial load
Concentrated load or reaction
Required strength for concentrated load or
reaction in presence of bending moment for
ASD
Required strength transmitted by bolt or
weld for ASD
Required compressive axial strength for
ASD
Professional factor
Required concentrated load within distance
of 0.3a on each side of brace
Required nominal brace strength
P Required strength for concentrated load or
reaction (concentrated load or reaction due
to factored loads) in presence of bending
moment
Required compressive axial strength
(factored compressive load)
P
a
Allowable load
P
allow
Allowable concentrated load or reaction for
one bearing stiffener
Allowable concentrated load or reaction for
one solid web sheet connecting top and
bottom flanges
P
a0
Allowable axial load determined for L = 0
P
cr
Critical load
P
crd
Distortional buckling load
NOMENCLATURE 407
P
cre
Overall buckling load
P
crl
Local buckling load
P
D
Force due to dead load
P
d
Load P at which diaphragm stiffness shall
be determined
P
Ex
Elastic buckling strength about x axis
P
Ey
Elastic buckling strength about y axis
P
e
Euler critical load
P
f
Axial force due to factored loads
Concentrated load or reaction due to
factored loads
Factored shear force transmitted by welding
P
fd
Load P from testing of bare test frame at
deflection equal to deflection for load of
0.4P
max
for stiffness
P
fn
Load P from testing of bare frame at
deflection equal to deflection for load of
P
max
for strength
P
i
Lateral force introduced into system at ith
purlin
P
L
Force to be resisted by intermediate beam
brace
Force due to live load
P
Lj
Anchorage force to be resisted by j th
anchorage device
P
m
Mean ratio of experimentally determined
ultimate load to predicted ultimate load of
test specimens
P
max
Maximum applied load P to test frame
P
n
Nominal axial strength of member
Nominal strength of connection component
Nominal bearing strength
Nominal tensile strength of welded member
Nominal bolt strength
Nominal web crippling strength
P
nc
Nominal web crippling strength (resistance)
of C- or Z-section with overhang(s)
P
nd
Nominal axial strength for distortional
buckling
P
ne
Nominal axial strength for overall buckling
P
nl
Nominal axial strength for local buckling
P
no
Nominal axial strength (resistance) of
member determined for F
n
= F
y
P
ns
Nominal shear strength (resistance) per
screw
P
nt
Nominal tension strength (resistance) of
screw or arc spot weld
P
not
Nominal pull-out strength (resistance) per
screw
P
nov
Nominal pull-over strength (resistance) per
screw
P
nv
Nominal shear strength (resistance) of arc
spot weld
P
R
Reduced modulus load
P
r
Required axial compressive strength
(resistance)
P
s
Concentrated load or reaction
P
ss
Nominal shear strength (resistance) of
screw
P
T
Tangent modulus load
P
ts
Nominal tension strength (resistance) of
screw
P
u
Required strength transmitted by weld for
LRFD
Required strength for concentrated load or
reaction in presence of bending moment for
LRFD
P
ul
Strength of connected sheet
P
u0
Observed ultimate load
P
up
Predicted ultimate load
P
us
Ultimate shear capacity per weld
P
ut
Applied tensile force
P
uv
Applied shear force
P
wc
Nominal web crippling strength (resistance)
for C-section flexural member
P
x
,P
y
Euler flexural buckling load about x and y
axes, respectively
P
y
Member yield strength
P
z
Torsional buckling load
P
zQ
= P
z
+
¯
Qd
2
/4r
2
0
P
0
Initial load
p Corrugation pitch
Q Required shear strength of connection
Required allowable shear strength of
connection
Stress and/or area factor to modify
allowable axial stress
Shear rigidity of diaphragm
Static moment of area between extreme
fiber and particular location at which shear
stress is desired, taken about neutral axis
Q
a
Area factor to modify members composed
entirely of stiffened elements
Q
a
Area factor determined by A
eff
/A
Q
i
Load effect
Q
m
Mean value of load effect
Q
s
Stress factor to modify members composed
entirely of unstiffened elements
Q
t
Safety factor for tensile load
¯
Q Design shear rigidity for two wallboards
Required shear strength of connection
¯
Q
a
=
¯
Q/A
¯
Q
t
= Qd
2
/4Ar
2
0
¯
Q
0
Sheathing parameter
q Design load on beam for spacing of
connectors
408 NOMENCLATURE
Transverse component of flange force
Ratio of R
/d
¯q Design shear rigidity for two wallboards
per inch of stud spacing
¯q
0
Factor used to determine design shear
rigidity
q
s
Factor used to reduce shear strength due to
web opening
q
w
Allowable uniform load
q
u
Maximum uniformly distributed load in
plane of web
R Coefficient
Inside bend radius
Modification factor
Radius of outside bend surface
Reduction factor
Required allowable strength for ASD
R
a
Allowable resistance or allowable design
strength
R
c
Factor used to reduce web crippling
strength due to web opening
R
f
Effect of factored loads
R
I
= I
s
/I
a
R
m
Mean value of resistance
R
n
Nominal block shear rupture design
strength
Nominal resistance
Nominal strength
R
r
Roof rain load
Reduction factor
R
u
Required strength for LRFD
R
Midline radius
R
∗
R/t ratio
r Radius of gyration
Bolt force ratio
Correction factor
r
b
Radius of gyration about axis of bending
r
cy
Radius of gyration of one C-section about
its centroidal axis parallel to web
r
I
Radius of gyration of I-section about axis
perpendicular to direction in which
buckling would occur for given conditions
of end support and intermediate bracing
r
i
Minimum radius of gyration of full
unreduced cross section
r
x
Radius of gyration of cross section about
centroidal principal axis
r
y
Radius of gyration of cross section about
centroidal principal axis
r
0
Polar radius of gyration of cross section
about shear center
¯r
0
=
β
x
e
y
+ β
y
e
x
+ I
0
/A
S Section modulus
Shear strength of spot welding
=1.28
√
E/F
Snow load
S
a
In-plane load-carrying capacity for
diaphragms
S
c
Elastic section modulus of effective section
calculated at stress f
c
relative to extreme
compression fiber
S
d
Design shear strength for diaphragm
S
e
Elastic section modulus of effective section
calculated with extreme compression or
tension fiber a t F
y
S
f
Elastic section modulus of full unreduced
section for extreme compression fiber
S
ft
Section modulus of full unreduced section
relative to extreme tension fiber about
appropriate axis
S
fy
Elastic section modulus of full unreduced
section relative to extreme fiber in first
yield
S
n
In-plane diaphragm nominal shear strength
(resistance)
S
u
Ultimate shear strength of diaphragm
S
x
Section modulus about x axis
S
x
Section modulus of beam computed for full
web area and effective width of
compression flange determined on basis
of F
y
S
xc
Compression section modulus of entire
section about major axis
S
yc
Compression section modulus of entire
section about axis normal to axis of
symmetry
S
ω
Warping statical moment
s Fastener spacing
Spacing in line of stress of welds, rivets, or
bolts connecting compression cover plate or
sheet to nonintegral stiffener or other
element
Weld spacing
Spacing of bolts perpendicular to line of
stress
Distance measured along middle line of
cross section from one end to point P
Center-to-center hole spacing
s
Longitudinal center-to-center spacing of
holes
s
end
Clear distance from hole at ends of member
s
lim
Limiting longitudinal spacing of
connections
NOMENCLATURE 409
s
max
Maximum permissible longitudinal spacing
of welds or other connectors joining two
C-sections to form an I- section
T Torsional reduction factor
Self-straining forces and effects caused by
temperature changes
Required tensile axial strength for ASD
Required tension strength of connection
T
a
Allowable tensile strength
T
f
Tension due to factored loads for LSD
Factored tensile force of connection for
LSD
T
n
Nominal tensile strength
T
s
Available strength of connection in tension
T
u
Required tensile axial strength for LRFD
Required tension strength of connection for
LRFD
T Required tensile axial strength (factored
tensile force)
Required tension strength (factored tensile
force) of connection
t Base steel thickness of any element or
section
Total combined base thickness (exclusive of
coatings) of s heets involved in shear
transfer
Thickness of coped web
t
c
Lesser of depth of penetration and
thickness t
2
t
e
Effective throat dimension for groove weld
Thickness of coped web
t
i
Steel thickness of member for segment i
Thickness of uncompressed glass fiber
blanket insulation
t
s
Thickness of bearing stiffener
t
w
Effective throat of weld
Steel washer thickness
t
1
Thickness of member in contact with screw
head
t
2
Thickness of member not in contact with
screw head
U Potential energy
Reduction factor for determining effective
net area
u Deflection or displacement in x direction
u
o
Initial deflection in x direction
V Required shear strength for ASD
V
a
Allowable shear force
V
D
Shear strength due to dead load
V
F
Coefficient of variation of fabrication factor
V
f
Shear force due to factored loads for LSD
Factored shear force of connection for LSD
V
L
Shear strength due to live load
V
M
Coefficient of variation of material ratio
V
n
Nominal shear strength
V
P
Coefficient of variation of
tested-to-predicted load ratios
V
Q
Coefficient of variation of load effect
V
R
Coefficient of variation of resistance
V
u
Required shear strength for LRFD
Required shear strength of connection for
LRFD
V
1
Strain energy in twisted column
V
2
Strain energy of supporting frame
V Required shear strength
v Deflection or displacement in y direction
Longitudinal shear stress
W Total uniform load
Wind load
Required strength from critical load
combination
W
pi
Total required vertical load supported by
i th purlin in a single bay
W
x
,W
y
Components of required strength W
W
∗
Ratio of length of centerline of full flange
of flexural members or of entire section of
tension or compression members to
thickness
w Flat width of element exclusive of fillets
Flat width of beam flange which contacts
bearing plate
Uniformly distributed load
w
Uniformly distributed load
w
cr
Uniform load to cause lateral buckling of
beam
w
D
Uniformly distributed dead load
w
f
Width of flange projection beyond web for
I-beam and similar sections or half the
distance between webs of box- or U-type
sections
Projection of flanges from inside face of
web
Flat width of flange
w
i
Required distributed gravity load supported
by ith purlin per unit width
w
L
Uniformly distributed live load
w
o
Out-to-out width
w
s
Whole width between webs or from web to
edge stiffener
w
w
Flat width of web
w
1
,w
2
Leg on weld
x Distance from concentrated load to brace
Distance measured along x axis
Nondimensional fastener location
410 NOMENCLATURE
Nearest distance between web hole and
edge of bearing
x
0
Distance from shear center to centroid
along principal x axis; x coordinate of
shear center, negative
Distance from centroid of flange to shear
centerofflange
¯x Distance from shear plane to centroid of
cross section
Y Yield stress of web steel divided by yield
point of stiffener steel
Y
i
Gravity load from LRFD or LSD load
combinations or 1.6 times ASD load
combinations applied a t level i
y Distance measured along y axis
y
c
Distance from neutral axis of beam to
centroid of equivalent column
y
cg
Distance from extreme fiber to neutral axis
in y direction
y
0
Distance from centroid of equivalent
column to its shear center; y coordinate of
shear center
y distance from centroid of flange to shear
centerofflange
Z Parameter to determine behavior of tubular
members
α Reduction factor
=1 − (x
0
/r
0
)
2
− (y
0
/r
0
)
2
Coefficient for purlin directions
Coefficient for conversion of units
Coefficient for strength (resistance) increase
due to overhang
Coefficient accounts for benefit of unbraced
length, L
m
, shorter than L
cr
Parameter for determining effective area of
stiffener
Second-order amplification coefficient
1/α
x
, 1/α
y
Magnification factors
β =1 − (x
0
/r
0
)
2
Spring constant
Coefficient
Reliability index
Value accounting for moment gradient
β
0
Target reliability index
β
act
Extensional stiffness of decking material
B
br,1
Required brace stiffness for single
compression member
β
id
Spring constant of elastic support
β
f
,β
1
,β
w
Terms used in Appendix C for computing
β
y
β
x
,β
y
Terms used in torsional and
torsional–flexural buckling analysis
γ Load factor
=1 − (y
0
/r
0
)
2
Actual shear strain in sheathing
Coefficient
γ
i
Coefficient
¯γ Permissible shear strain of sheathing
Deflection
Average value of deflections obtained from
load–deflection curves for load of 0.4P
ult
b
In-plane flexural deflection
b
Computed bending deflection
d
Net shear deflection of diaphragm test at
load of 0.4P
max
n
Net shear deflection
s
In-plane shear deflection
s
Shear deflection for load of 0.4P
ult
ss
In-plane deflection due to seam slip
tf
Lateral displacement of purlin top flange at
line of restraint
δ, δ
i
Coefficients
δ
0
Maximum deflection due to transverse
loading
δ
u
Horizontal displacement of shear center due
to unit load
δ
uφ
Horizontal displacement of shear center due
to unit moment
δ
φ
Rotation of column due to unit moment
ε
cu
Maximum compression strain
ε
1
Local elongation
ε
u
Uniform elongation
ε
y
Yield strain
η Plasticity reduction factor
θ Angle between web and bearing surface,
≥45
◦
but no more than 90
◦
Angle between vertical and plane of web of
Z-section, deg
Angle between an element and its edge
stiffener
λ Length of half sine wave
=
√
GJ /EC
w
Slenderness factor
λ
c
Column slenderness parameter
λ
d
Distortional buckling slenderness factor
λ
l
,λ
2
,λ
3
,λ
4
Parameters used in determining
compression strain factor
λ
l
Local buckling slenderness factor
μ Poisson’s ratio for steel, = 0.30
ρ Perpendicular distance to tangent line from
centroid
Reduction factor
ρ
0
Perpendicular distance to tangent line from
shear center
NOMENCLATURE 411
σ Stress related to shear strain in sheathing
Stress
σ
b
Bearing stress at failure of connection
σ
bC
Maximum compression bending stress
caused by M
C
σ
bT
Maximum compression bending stress
caused by M
T
σ
b1
Maximum compression bending stress in
section caused by σ
TF
, = σ
TF
ec/r
2
y
σ
b2
= σ
TF
x
0
c/r
2
y
σ
CR
Theoretical elastic buckling stress
σ
cr
Critical buckling stress
σ
e
=π
2
E/(KL
b
/r
b
)
2
σ
ex
=π
2
E/(K
x
L
x
/r
x
)
2
σ
exy
=π
2
EI
xy
/(AL
2
)
σ
ey
=π
2
E/(K
y
L
y
/r
y
)
2
σ
max
Maximum local buckling stress
σ
net
Failure stress in net section
σ
R
Critical buckling stress based on reduced
modulus method
σ
R
Standard deviation of resistance
σ
Q
Standard deviation of load effect
σ
S
Average failing stress
σ
T
Critical buckling stress based on tangent
modulus method
σ
TF
Average elastic flexural–torsional buckling
stress
σ
TFO
Elastic flexural–torsional buckling stress
σ
TFT
Inelastic flexural–torsional buckling stress
σ
t
Torsional buckling stress
σ
tQ
= σ
t
+
¯
Q
t
σ
w
Warping longitudinal stress
τ = E
t
/E
Shear stress
τ
b
Parameter for reduced stiffness using
second-order analysis
τ
cr
Critical shear buckling stress
τ
cri
Initial critical shear buckling stress
τ
pr
Proportional limit in shear
τ
t
Pure torsional shear stress (or St. Venant
shear stress)
τ
u
Ultimate shear strength of weld metal
τ
W
Warping shear stress
τ
y
Yield stress in shear
Amplification factor
φ Angle of twist about z axis.
Resistance factor
φ
b
Resistance factor for bending strength
φ
c
Resistance factor for concentrically loaded
compression member
φ
d
Resistance factor for diaphragm shear
φ
t
Resistance factor for tension member or
shear
φ
v
Resistance factor for shear strength
φ
w
Resistance factor for web crippling strength
φ
0
Initial angle of twist about z axis
=π
2
δ
0
EI/M
0
L
2
− 1
=|f
2
/f
1
|
ω Deflection of plate perpendicular to surface
=
∫
2
0
ρds
ω
n
Normalized unit warping
ω
0
=
∫
s
0
ρ
0
ds
ω, ω
i
Coefficients
ξ
web
Stress gradient in web
Safety factor
b
Safety factor for bending strength
c
Safety factor for concentrically loaded
compression strength
d
Safety factor for diaphragms
t
Safety factor for tension strength
v
Safety factor for shear strength
w
Safety factor for web crippling strength
Acronyms and Abbreviations
ACRONYMS
AASHTO American Association of State Highway
and Transportation Officials, 341
National Press Building, Washington, DC
20004.
AISC American Institute of Steel Construction,
One East Wacker Drive, Suite 3100,
Chicago, IL 60601.
AISI American Iron and Steel Institute, 1140
Connecticut Avenue, NW, Suite 705,
Washington, DC 20036.
AREA American Railway Engineering
Association, 59 East Van Buren Street,
Chicago, IL 60605.
ASCE American Society of Civil Engineers, 1801
Alexander Bell Drive, Reston, VA 20191.
ASTM American Society for Testing and
Materials, 100 Bar Harbor Drive, West
Conshohocken, PA 19428.
AWS American Welding Society, 550 N. W.
LeJeune Road, Miami, FL 33135.
CCFSS Wei-Wen Yu Center for Cold-Formed Steel
Structures, Missouri University of
Science and Technology (formerly
University of Missouri-Rolla), Rolla, MO
65409.
CFSEI Cold-Formed Steel Engineers Institute
(formerly Light Gauge Steel Engineers
Association), 1201 15th Street, NW,
Suite 320, Washington, DC 20005.
CRC Column Research Council (see SSRC).
CSA Canadian Standards Association, 178
Rexdale Boulevard, Rexdale, Ontario,
Canada M9W 1R3.
CSSBI Canadian Sheet Steel Building Institute,
652 Bishop St. North Unit 2a,
Cambridge, Ontario, Canada N 3H 4V6.
ECCS European Convention for Constructional
Steelwork, London.
IABSE International Association for Bridge and
Structural Engineering, Swiss Federal
Institute of Technology, Zurich,
Switzerland.
IBC International Building Code.
LGSEA Light Gauge Steel Engineers
Association,1201 15th Street, NW, Suite
320, Washington, DC 20005
MBMA Metal Building Manufacturers Association,
1300 Sumner Avenue, Cleveland, OH
44115.
MCA Metal Construction Association, 104 S.
Michigan Avenue, Suite 1500, Chicago,
IL 60603.
NACA National Advisory Committee for
Aeronautics (see NASA).
NASA National Aeronautics and Space
Administration (formerly NACA),
Washington, DC.
SFA Steel Framing Alliance, 1201 15th Street,
NW, Suite 320, Washington, DC 20005.
RMI Rack Manufacturers Institute, 8720 Red
Oak Boulevard, Suite 201, Charlotte, NC
28217.
SDI Steel Deck Institute, P.O. Box 25, Fox
River Grove, IL 60021.
SJI Steel Joist Institute, 3127 10th Ave., North
Ext., Myrtle Beach, SC 29577.
SSMA Steel Stud Manufacturers Association, 8 S.
Michigan Avenue, Suite 1000, Chicago,
IL 60603.
SSRC Structural Stability Research Council
(formerly CRC), Missouri University of
Science and Technology (formerly
University of Missouri-Rolla), Rolla, MO
65409.
ABBREVIATIONS
ASD Allowable strength design (formerly
allowable stress design)
c.g. Center of gravity
cm Centimeter
EOF End one-flange loading
ETF End two-flange loading
ft/min
Feet per minute
413
414 ACRONYMS AND ABBREVIATIONS
GPa Gigapascal
in. Inch
IOF Interior one-flange loading
ITF Interior two-flange loading
kg Kilogram
kg/cm
2
Kilograms per square centimeter
kip 1000 pounds
kN Kilonewton
kN/mm
2
Kilonewtons per square millimeter
ksi Kips per square inch
lb/ft Pounds per foot
lb/ft
2
Pounds per square foot
LF Load factor
LRFD Load and resistance factor design
LSD Limit states design
m Meter
MKS Measurement unit (force in kilograms and
length in centimeters)
m/min Meters per minute
mm Millimeter
MPa Megapascal
N/m
2
Newtons per s quare meter
oz/ft
2
Ounces per square foot
psf Pounds per square foot
psi Pounds per square inch
s.c. Shear center
s.c.e. Stiffened compression element
SF Safety factor
SS Structural steel
u.c.e. Unstiffened compression element