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Design of Crane Runways
According to CSA and CMAA
By: Victoria Lake
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
1
Outline
Introduction
Types of Runways
Typical Sections
CSA Standards
CMAA Standards
Crane Classes
Types of Loads
Load Combinations
Example
Conclusion
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
2
Introduction
Runway is beam that supports crane
bridge and trolley
RUNWAY BEAMS

Special Considerations
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07/07/2015
Should be stiff to limit deflections
Laterally unsupported, except at the
columns
Subject to impact
Unsymmetrical bending due to
lateral thrust from starting/stopping
of crane trolley
Longitudinal loads due to
starting/stopping of crane bridge
Greater Risk of Fatigue due to
repeated loadings
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
3
Types of Cranes
Top Running
07/07/2015
Under Running
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
4
Common Runway Beam Sections
(a) wide flange rolled section
(b) wide flange with added plate
to top flange
(c) wide flange with added
channel to top flange
(d-h) other variations
(i) horizontal truss
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
5
Manufacturer and Client Data
Manufacturer to provide:
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Maximum wheel loads
Wheel spacing
Trolley weight
Clearances required
Client to provide:
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07/07/2015
Span
Capacity needed
Type of crane preferred
Length of runway
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
6
CSA Standards
Limit States Design per CSA S16-01
Appendix C: Crane Supporting
Structures
Deflection
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Vertical, capacity > 225kN, L/800
Vertical, capacity < 225kN, L/600
Lateral, L/600
New Publication


07/07/2015
CISC: Crane Supporting Steel
Structures (2005)
Provides more detailed procedures
and requirements
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
7
CMAA Standards
Based on Allowable Stress Design
Procedure checks

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Allowable stresses
Combined stresses
Buckling, local and lateral torsional
Longitudinal, vertical and diaphragm
stiffeners
Deflection is limited to 1/600 length
of the span
Camber not to exceed 1/888 length
of the span
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
8
Crane Classes (from CMAA and CSA)
Crane
Class
Load Cycles
(1000’s)
Lifts (/hr)
Capacity
Speed
Class A
Standby
0–100
1>
0 – occasional full rated
capacity
Slow
Class B
Light
20–200
2-5
Light, 0 – few full rated
capacity
Slow
Class C
Moderate
20–500
5-10
50% rated capacity,
>65% full capacity
Moderate
Class D
Heavy
100–2000
10-20
>50% rated capacity
Fast
Class E
Severe
500–2000
>20
At or near rated
capacity
Fast
Class F
Continuous
>2000
continuous
100% rated
Continuous
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
9
Principal Loads
Vertical Inertia Forces
Dead Load (DL)

weight of all elements of the
bridge structure, the machinery
parts and the fixed equipment
supported by the structure
Trolley Load (TL)

Weight of trolley and any
equipment attached to it
Forces due to the motion of the
crane or crane components
Forces due to lifting of the hoist
load
Dead Load Factor (DLF)

applied the dead loads of the
crane, trolley, and its associated
equipment
Related to travel speed
Hoist Load Factor (HLF)
The lifted load is the sum of the
working load and the lifting
devices used for handling and
holding the load, for example the
load block, lifting beam, bucket,
magnet, and grab
07/07/2015
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Lifted Load (LL)
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applied to the motion of the rated
load in the vertical direction
Also inertia forces and the mass
forces due to sudden lifting of
the hoist load
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
10
Principal Loads, cont…
Inertia Forces From Drives (IFD),
also referred to as Side Thrust

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Forces from acceleration,
deceleration, trolley impact with
end stop
Applied to both live and dead
loads
CMAA: Lateral load is calculated
as a percentage of the vertical
load, 7.8 times the lateral
acceleration or deceleration rate
( > 2.5% of the vertical load)
CISC: 20% of combined weight
of lifted load and trolley (for caboperated cranes)
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
11
Additional Loads
Operating Wind Load (WLO)

Forces due to Skewing (SK)
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
0.19
outdoor crane is 5 lbs/ft2 of the
projected area of the crane with
is exposed to wind
should be divided equally
between the 2 girders
horizontal forces normal to the
rail from wheels
obtained multiplying the vertical
load exerted on each wheel by
coefficient Ssk which depends
upon the ratio of the span to the
wheel base
RATIO 
07/07/2015
0.17
0.15
0.13
Ssk

0.11
0.09
0.07
0.05
0.03
2
3
4
5
6
7
8
SPAN
WHEELBASE
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
12
Extraordinary Loads
Stored Wind Load (WLS)


maximum wind load that the
crane can withstand when it is
not in service
depends on the height of the
crane above the ground, its
geographical location, and its
degree of exposure to prevailing
winds
Collision Forces (CF)

Resulting from crane hitting
bumper stops
Torsional Forces and Moments


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Starting/stopping of bridge
motors
Due to vertical loads
Due to lateral loads
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
13
CMAA Load Combinations
Case 1

regular use under principal
loading (stress level 1)
DL(DLFB )+TL(DLFT )+LL(1+HLF)+IFD
Case 2

regular use under principal and
additional loading (stress level 2)
DL(DLFB )+TL(DLFT )+LL(1+HLF)+IFD+WLO+SK
Case 3
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Subject to extraordinary loads
(stress level 3)
applies mostly to outdoor cranes
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Out of Service Wind
DL+TL+WLS
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In collision
DL+TL+LL+CF
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Test Loads
Not more than 125% rated load

07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
14
CISC Load Combinations
(vertical + side thrust)
(C1 + impact + longitudinal)
(vertical for multiple cranes + side thrust + long.)
(vertical + side thrust + long., all multiple cranes)
(vertical + side thrust + impact + long., all multiple)
(vertical + side thrust, all multiple)
(vertical + side thrust + bumper impact
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
15
Example: Design Mono-symmetric Runway Beam
INPUT
Span
Number of Cranes, Each Runway
Crane Hook Capacity - Number of Hook(s) each
Crane Hook Capacity - Capacity each hook
Weight of Crane Trolley
Bridge Wheels per Rail - Total Number
Bridge Wheels per Rail - Driven
Bridge Wheel Spacing
Min. Distance Between Wheels of Crane in Tandem
Crane Rail - Description
Crane Rail - Self Load
Deflection Criteria - Vertical Limit (one crane, not including impact)
Deflection Criteria - Horizontal Limit
irs
ncr
nh
ch
wct
nbwr
nbwd
bws
dbwt
crd
crsl
dcvl
dchl
=
=
=
=
=
=
=
=
=
=
=
= irs/600
= irs/400
Lifted Load
Trolley Load
ll
tl
= (ch*1000)*9.81/1000 =
= wct*9.81/1000
=
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
=
=
=
=
=
=
=
=
=
=
=
=
=
10670
1
1
22.68
2721
2
1
3050
169
89
19.8
17.783
26.675
mm
tonnes
kg
mm
kN
mm
kg/m
mm
mm
222.49 kN
26.69 kN
16
Example: Load Diagram
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
17
Example: Determine Moments and Side Thrust
CALCULATIONS
MOMENTS
point of max. bending moment
left reaction
right reaction
MLL, under wheel load closest to mid-span
moment due to impact
estimated dead load, including rail and conductors
MDL
pmbm
lr
rr
mll
mdi
edl
mdl
=
=
=
=
=
=
=
0.5*(irs-bws/2)
=
(dbwt*(irs-(pmbm+bws))/irs)+(dbwt*(irs-pmbm)/irs)=
(dbwt*(pmbm+bws)/irs)+(dbwt*(pmbm/irs))
=
lr*pmbm
=
0.25*mll
=
=
(edl*(irs/1000)^2)/8
=
4572.5
144.85
193.15
662.31
165.6
2.64
37.57
mm
kN
kN
kN-m
kN-m
kN/m
kN-m
Mfx, factored moment
mfx
= 1.25*mdl+1.5*(mll+mdi)
=
1288.79 kN-m
side thrust
side thrust, per wheel
ratio of side thrust to max. wheel load
specified moment due to side thrust, MH
st
stpw
rstwl
mh
=
=
=
=
=
=
=
=
49.84 kN
12.46 kN
0.0737
48.83 kN-m
factored moment due to side thrust, MHF
mhf
= 1.5*mh
=
73.24 kN-m
SIDE THRUST
07/07/2015
0.2*(ll+tl)
st/4
stpw/dbwt
rstwl*mll
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
18
Example: Select trial section
SELECT TRIAL SECTION
Ix1
vertical deflection, based on Ix1
less than allowable?
Ix needed? based on vertical deflection
Iy needed? based on horizontal deflection
Ix1
=
delta1 =
ixr
iyr
delta1<dcvl
= (delta1/dcvl)*Ix1
= (delta1/dchl)*rstwl*Ix1
=
=
=
=
=
2.00E+09
18.5
FALSE
2.081E+09
1.023E+08
mm4
mm
mm4
mm4
In this case, W610x217 with a
381x12.7 cover plate is chosen
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
19
Example: Subsequent Procedure
After selection of trial section, the
procedure is as follows:
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Check class of section (S16-01,
Clause 11.2)
Calculate plastic moment, Mp,
and plastic section modulus, Z
Calculate elastic section
properties (built-up)
Calculate section properties for
mono-symmetric analysis (not
covered in CSA, use CISC
Section 5.9)
Check strength of section in
bending
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Completes check for bending
Next:
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07/07/2015
Calculate limiting unbraced length
for plastic bending capacity and
inelastic buckling
Calculate factored resistance
Calculate distribution of side thrust
Check overall member strength
Check stability (lateral torsional
buckling)
Design stiffeners
Design bearings and lateral
restraints
Design connections (welds and
bolts)
Check fatigue resistance
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
20
Conclusion
Complicated procedure
Must design a stiff runway to prevent
deflections
Also consider potential for fatigue
due to repeated loading
Which standards to follow: CSA or
CMAA?
CISC’s new “Guide to Crane
Supporting Structures” provides
good examples and information
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
21
The end.
07/07/2015
Design of Crane Runways
According to CSA and CMAA by
Victoria Lake
22