Page 1 of 38 JOB NO. DATE 11-Mar-2022 CUSTOMER DESIGNED BY DESCRIPTION CHECKED BY DESIGN OF CRANE BEAM THE DESIGN DATA ARE AS FOLLOWS CRANE CAPACITY = 30 KN SPAN BETWEEN CRANE RAILS = 18 M WEIGHT OF CRANE = 30 KN WEIGHT OF CRAB = 10 KN MINIMUM HOOK APPROACH = 0.5 M END CARRIAGE WHEELCENTRES = 2.5 M SPAN OFCRANE GIRDER = 15 M SELF WEIGHT OF CRANE GIRDER = 25 KN 2520 GRADE OF STEEL = S275 250 MODULUS OF ELASTICITY OF STEEL Es = 205000 SIZE OF WELD = 6 mm TYPE OF CRANE RAIL = DIAMETER OD CRANE WHEEL = 200 mm (1) MAXIMUM WHEEL LOADS, MOMENTS AND SHEAR THE CRANE LOADS ARE SHOWN IN FIG.(a). THE MAXI. STATIC WHEEL LOADS @ A; = 30/4+((30+10)x17.5)/18x2 = 26.95 KN THE VERTICAL WHEEL LOAD, INCLUDING IMPACT (THE MAXI.STATIC WHEEL LOADS SHALL BE INCREASED BY 25% FOR E.O.C.) = 1.25 x26.95 = 33.69 KN THE HORI. SURGE LOAD TRANSMITTED BY FRICTION TO THE RAILTHROUGH FOUR WHEELS: (THE HORI. FORCE ACTING TRANSVERSE TO THE RAILS SHALL BE TAKEN AS 10% OF THE COMBINED WT. OF THE CRAB AND THE LOAD LIFTED) = 10%(30+10)/4 = 1 KN LOAD FACTORS: (REFER BS5950-2000; TABLE 2 PARTIALFACTORS FOR LOADS) DEAD LOAD - SELF WEIGHT ϒf = 1.4 VERT.& HORI. CRANE LOADS CONSIDERED SEPERATELY ϒf = 1.6 VERT.& HORI. CRANE LOADS ACTING TOGETHER ϒf = 1.4 THE CRANE LOADS IN A POSITION TO GIVE MAXI. VERT & HORI MOMENTS & MAXI VERT SHEAR.FIG.(b) DESIGN A SIMPLY SUPPORTED BEAM TO CARRY AN ELECTRIC OVERHEAD CRANE. N/mm 2 N/mm 2
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Page 1 of 39
JOB NO. DATE 9-Apr-2023CUSTOMER DESIGNED BY
DESCRIPTION CHECKED BY
DESIGN OF CRANE BEAM
THE DESIGN DATA ARE AS FOLLOWS
CRANE CAPACITY = 30 KNSPAN BETWEEN CRANE RAILS = 18 MWEIGHT OF CRANE = 30 KNWEIGHT OF CRAB = 10 KNMINIMUM HOOK APPROACH = 0.5 MEND CARRIAGE WHEELCENTRES = 2.5 MSPAN OFCRANE GIRDER = 15 MSELF WEIGHT OF CRANE GIRDER = 25 KN 2520GRADE OF STEEL = S275
250
MODULUS OF ELASTICITY OF STEEL Es = 205000SIZE OF WELD = 6 mmTYPE OF CRANE RAIL =DIAMETER OD CRANE WHEEL = 200 mm
(1) MAXIMUM WHEEL LOADS, MOMENTS AND SHEAR
THE CRANE LOADS ARE SHOWN IN FIG.(a).THE MAXI. STATIC WHEEL LOADS @ A;
= 30/4+((30+10)x17.5)/18x2
= 26.95 KN
THE VERTICAL WHEEL LOAD, INCLUDING IMPACT
(THE MAXI.STATIC WHEEL LOADS SHALL BE INCREASED BY 25% FOR E.O.C.)
= 1.25 x26.95
= 33.69 KN
THE HORI. SURGE LOAD TRANSMITTED BY FRICTION TO THE RAILTHROUGH FOUR WHEELS:
(THE HORI. FORCE ACTING TRANSVERSE TO THE RAILS SHALL BE TAKENAS 10% OF THE COMBINED WT. OF THE CRAB AND THE LOAD LIFTED)
= 10%(30+10)/4
= 1 KN
LOAD FACTORS:(REFER BS5950-2000; TABLE 2 PARTIALFACTORS FOR LOADS)
DEAD LOAD - SELF WEIGHT ϒf = 1.4
VERT.& HORI. CRANE LOADS CONSIDERED SEPERATELY
ϒf = 1.6
VERT.& HORI. CRANE LOADS ACTING TOGETHER
ϒf = 1.4
THE CRANE LOADS IN A POSITION TO GIVE MAXI. VERT & HORI MOMENTS & MAXI VERT SHEAR.FIG.(b)
DESIGN A SIMPLY SUPPORTED BEAM TO CARRY AN ELECTRIC OVERHEAD CRANE.
N/mm2
N/mm2
Page 2 of 39
JOB NO. DATE 9-Apr-2023CUSTOMER DESIGNED BY
DESCRIPTION CHECKED BY
10 KNA B
26.95 kN/wheel 300.5 17.5
18
CRANE GIRDER CENTRESFIG.( a ) CRANE LOADS
33.69 33.69
C SELF WT.= 25A B
0.625 0.6255.625 2.5 6.875
15
FIG.(b) VERTICAL LOADS - MAXIMUM MOMENT
1 1
A C B
FIG.(c) HORIZONTAL LOADS - MAXIMUM MOMENTS
33.69 33.69 SELF WT.= 25
A B2.5 12.5
FIG.(d) LOADS CAUSING MAXI. VERTICAL SHEAR
CGLoads
Page 3 of 39
JOB NO. DATE 9-Apr-2023CUSTOMER DESIGNED BY
DESCRIPTION CHECKED BY
THE MAXI VERT MOMENTS DUE TO DEAD LOAD & CRANE LOADS ARE CALCULATED SEPERATELY:
DEAD LOAD;
25 kN / 2
12.5 KN
Mc = (12.5 x 6.875) - (25 x 6.875 x 6.875 / (15 x 2))
Mc = 46.55 KN m.
CRANE LOAD,INCLUDING IMPACT
33.69(5.625 + 0.625 + 2.5) / 15
30.89 KN
Mc = 30.89 x 6.875
Mc = 212.37 KN m.
CRANE LOAD WITH NO IMPACT
Mc = 212.37 x 26.95 / 33.69
Mc = 169.89 KN m.
THE MAXI HORI MOMENT DUE TO CRANE SURGE;
1(5.625 + 5.625 + 2.5) / 15
0.92 KN
Mc = 0.92 x 6.875
Mc = 6.33 KN m.
THE MAXI VERTICAL SHEAR;
12.5 KN
CRANE LOADS, INCLUDING IMPACT
33.69 + 33.69 x 12.5/15
61.77 KN
THE LOAD FACTORS ARE INTRODUCED TO CALCULATE THE DESIGN MOMENTS & SHEAR FORTHE VARIOUS LOAD COMBINATIONS:
(1) VERTICAL CRANE LOADS WITH IMPACT & NO HORI. CRANE LOAD.MAXIMUM MOMENT
Mc = (1.4 x 46.55) + (1.6 x 212.37)
Mc = 404.97 KN m.
MAXIMUM SHEAR
(1.4 x 12.5) + (1.6 x 61.77)
116.34 KN
(2) HORI. CRANE LOADS & VERT.CRANE LOADS WITH NO IMPACT.
MAXIMUM HORIZONTAL MOMENT,Mc = 1.6 x 6.33
Mc = 10.13 KN m.
MAXIMUM VERTICAL MOMENTMc = (1.4 x 46.55) + (1.6 x 169.89)
(3) MOMENT CAPACITY FOR THE TOP SECTION FOR THE y-y AXIS:
Mcy = 265 x 30573280
Mcy = 8101.92 KN m 80 7.110
Zyy = 30573280 mm3
x = 125 mm(4) CHECK BEAM BENDING: y= 76.16 mm
Ixx = 219294816
(1) VERTICAL MOMENT, NO HORI. MOMENT Iyy = 3821660000
Zxx = 2879396.23
Mx = 404.97 < Mb = 539.09 KN M. Zyy = 30573280
(2) VERTICAL MOMENT NO IMPACT + HORIZONTAL MOMENT
(337 / 539.09 + 10.13 / 8101.92)
0.63 < 1
(3) VERTICAL MOMENT WITH IMPACT + HORIZONTAL MOMENT:
362.49 / 539.09 + 8.87 / 8101.92
0.674 < 1
THE CRANE GIRDER IS SATISFACTORY IN BENDING
(5) SHEAR CAPACITY (see scction 4.2.3, BS-5950-1-2000)
Pv = 0.6 x 760 x 8 x 265
Pv = 966.72 KN
MAXIMUM FACTORED SHEAR = 116.34 KN
FROM TABLE 17 BENDING STRENGTH pb (N/mm2) pg.52 FOR WELDED S/C FOR py = 265 N/mm2
pb = N/mm2
mm4
mm4
mm3
mm3
x
MxMbffffffffff
Mypy Zyffffffffffffffffff
MxMbffffffffff
Mypy Zyffffffffffffffffff
Page 10 of 39
JOB NO. DATE 9-Apr-2023CUSTOMER DESIGNED BY
DESCRIPTION CHECKED BY
(6) WELD BETWEEN CHANNEL AND UNIVERSAL BEAM:
THE DIMENSION FOR DETERMINING THE HORIZONTAL SHEAR ARE SHOWN IN FIGURE.THE LOCATION OF THE CENTROIDAL AXIX IS TAKEN FROM THE STRUCTURAL STEELWORK HANDBOOK.
250
13.55 x = 125 mm275.3 y = 491.8 mm
261.75 Ixx = 140751.73
Iyy = 382655.16767.1
491.8
HORIZONTAL SHEAR FORCE IN EACH WELD;
(116.34 x 38.66 x 100 x 261.75)/(140751.73 x 10000 )
0.09 KN / mm
SIZE OF WELD = 6 mmIN THE SIMPLE METHOD, THE STRENGTH OF A FILLET WELDIS CALCULATED USING THE THROAT THICKNESS.
220
STRENGTH OF WELD = 0.7 x 6 x 220/ 1000 = 0.924 KN/mm
PROVIDE 6 mm CONTINIOUS FILLET (WELD STRENGTH = 0.924 KN/mm )
cm4
cm4
FOR THE 900 FILLET WELD, THE THROAT THOCKNESS IS TAKEN AS 0.7 TIMES THE SIZE OR LEG LENGTH:
STRENGTH OF WELD = 0.7 LEG LENGTH x pw / 103 KN/mm
DESIGN STRENGTH OF FILLET WELDS pw (KN/mm2) = KN/mm2
Page 11 of 39
JOB NO. DATE 9-Apr-2023CUSTOMER DESIGNED BY
DESCRIPTION CHECKED BY
(7) WEB BEARING AND BUCKLING:
20.2
389.87380
760 719.6
8
20.2
9.87
STIFF BEARING WEB BUCKLING
LOAD DISPERSION AT SUPPORT WITH 1:2.5 DISPERSION
WEB BEARING:
10 + 10.2 = 20.2 mm
50.5
Rx = 116.34 KN (MAXI. SUPPORT REACTION)
116.34 x 1000 / ( 8 x 265 / 1.1 ) - 50.5
9.87 mm
WEB BEARING AT SUPPORT REQUIRES A MINIMUM STIFF BEARING OF 9.87 mm
60.37
BEARING CAPACITY = 60.37 x 8 x 265 / 1000
20.2 BEARING CAPACITY = 127.99 KN
9.87 HENCE 127.99 > 116.34 SATISFACTORY
WEB BEARING
AT POINT OF CONCENTRATED LOADS (WHEEL LOADS OR REACTION) THE WEB OF THE GIRDER MUST BE CHACKED FOR LOACAL BUCKLING. THE DISPERSION LENGTH UNDER WHEEL ( THE DIAM. OF WHEEL TO BE 200 AND ASSUMING AN ANGLE OF DISPERSION OF 45 DEGREE)
BUCKLING RESISTANCE : THE BUCKLING RESISTANCE Px OF THE WEB SHOULD BE TAKEN AS;
(REFERANCE- C.4.5.3.1, BS-5950-1-2000)
Px = (200 + 0.7 x 719.6) / ( 1.4 x 719.6) x (25 x 1.0 x 8)/ (SQRT (60.37 x 719.6) x 127.99
THE VERTICAL DEFLECTION DUE TO THE STATIC WHEEL LOAD MUST NOT EXCEED:
SPAN / 600 = 15 x 1000 / 600 = 25 mm
THE HORIZONTAL DEFLECTION DUE TO CRANE SURGE MUST NOT EXCEED:
SPAN / 500 = 15 x 1000 / 500 = 30 mmTHE VERTICAL DEFLECTION AT THE CENTRE WITH THE LOADS IN POSITION FOR MAXIMUM MOMENT IS
16.312 mm SATISFACTORY
IF THE LOADS ARE PLACED EQUIDISTANT ABOUT THE CENTRE LINE OF BEAM a = c is 6.25 m.
26.95 26.95
6.25 2.5 6.25 16.426 mm
15 SATISFACTORY
THIS GIVES THE MAXIMUM DEFLECTION
THE HORIZONTAL DEFLECTION DUE TO DUE TO THE SURGE LOADS:
1 1
6.25 2.5 6.25 0.18 mm15
SATISFACTORY
A 25 Kg/m CRANE RAIL IS USED, AND THE HEIGHT HR IS 65 mm.
RAIL
δ=
δ=
δ=
Deflection at centre PL3
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4 a3 c3b c
L3
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MK 5wL3
384EIffffffffffffffffffff
Page 14 of 39
JOB NO. DATE 9-Apr-2023CUSTOMER DESIGNED BY
DESCRIPTION CHECKED BY
FATIGUE RESISTANT DESIGN
CRANE CAPACITY = 30 KNSPAN BETWEEN CRANE RAILS = 18 MWEIGHT OF CRANE = 30 KNWEIGHT OF CRAB = 10 KNMINIMUM HOOK APPROACH = 0.5 MEND CARRIAGE WHEELCENTRES = 2.5 MSPAN OFCRANE GIRDER = 15 MSELF WEIGHT OF CRANE GIRDER = 25 KNGRADE OF STEEL = S275
250 N/mm2MODULUS OF ELASTICITY OF STEEL Es = 205000 N/mm2SECTION USED FOR THE GIRDER = GirderCRANE OPERATION (days/year) = 200 days/yearHOUR PER DAY = 8 hr/dayTRIPS PER HOUR @ THIS LOAD LEVEL = 3 cycles/hourDESIGN LIFE OF BUILDING = 50 years
THE GANTRY GIRDER RECEIVES A MAXIMUM OF 80 % OF THE TOTAL LOAD AS THE REACTIVE FORCE
IT IS ASSUMED THAT THIS FORCE IS APPLIED TO THE GIRDER AS A SINGLE CONCENTRATED LOAD.
NUMBER OF STRESS CYCLES (equal number of load cycles in this case)
N = (3cycles/hour) (8hr/day) (200days/year) (50years)
N = 240000 cycles
DETAIL CATEGORY AND FATIGUE STRENGTH
THE PROVIDED BEAM CORRESPONDS TO DETAIL CATEGORY = 118(AS PER TABLE 13.3(1) OF THE IS:800-2007 CODE.)
FROM FIG.13.1 IS:800-2007; READ THE CATEGORY 118 LINE AT N = 240000 CYCLES TO FIND THATUNCORRECTED FATIGUE STRENGTH IS = 330 Mpa.
THE FATIGUE STRENGTH OF THIS DETAIL CAN ALSO BE CALCULATED USING C.13.5 OF IS:800-2007
HOWEVER, THE FOLLOWING POINTS HAVE TO BE BORNE IN MIND.1. THE NUMBER OF STRESS CYCLES WILL NOT ALWAYS BE EQUAL TO THE NUMBER OF LOADCYCLES. FOR EXAMPLE, IN A CONTINUOUS BEAM OR WHEN A MULTIPLE-AXLE VEHICLETRANSVERSES A MEMBER, MORE THAN ONE STRESS CYCLE COULD OCCUR.2. SINCE THE STRESS DUE TO THE DEAD LOAD IS ALWAYS PRESENT, THE CHANGE IN STRESS INTHE MEMBER COULD BE TAKEN EQUAL TO THE CHANGE IN STRESS PRODUCED BY THE MOVING(LIVE) LOAD.3. OF COURSE, WE CAN ALSO COMPARE THE NUMBER OF CYCLES PERMITTED AT THE ACTUALSTRESS RANGE OF 36.81 Mpa
FROM TABLE; log C FOR CATEGORY 118 AND N< 5 x 10^5 = 12.25
SINCE THE ACTUAL NUMBER OF CYCLES IS ONLY 240000,THIS ALSO SHOWS THAT THE SIZE OF THE GIRDER IS SUFFICIENT.
log N log c @m log ff
Page 17 of 39
JOB NO. DATE 9-Apr-2023CUSTOMER DESIGNED BY
DESCRIPTION CHECKED BY
REFERANCES: BS 5950-1:2000 STRUCTURAL USE OF STEELWORK IN BUILDINGIS 800:2007 CODE OF PRACTICE FOR GENERAL CONSTRUCTION IN STEEL (3rd REV.)STRUCTURAL STEELWORK:DESIGN TO LIMIT STATE THEORY BY DENNIS LAM, THIEN-CHEONG ANG - 3RD EDDESIGN OF STEEL STRUCTURES (L.S.M) BY N.SUBRAMANIAN
REFERANCE IS800-2007
Page 18 of 39
JOB NO. DATE 9-Apr-2023CUSTOMER DESIGNED BY
DESCRIPTION CHECKED BY
Page 19 of 39
JOB NO. DATE 9-Apr-2023CUSTOMER DESIGNED BY
DESCRIPTION CHECKED BY
NAME STAADNAME AX D Bf Tf Tw Ixcm^2 mm mm mm mm cm^4