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Kumpulan Jurutera Perunding PROJECT : SG2/SG3 JOB NO : DESIGNED BY : SAID DATE : 18-Apr-23
STRUCTURAL DESIGN OF BOX CULVERTS ( HB HIGHWAY LOAD )
CULVERT NO. : 1.00m x 1.00m
INPUT DATA
DIMENSIONS OF R.C BOX
Internal width = 1000 mm A DInternal height = 1000 mmWall thickness = 230 mmSlab thickness = 230 mmEffective width = 1230 mmEffective height = 1230 mm B C
ASSUMPTIONS
Thickness of pavement = 90 mm Wearing = 40 mmBinder = 50 mm
Unit weight of soil = 20Unit weight of concrete = 24Unit weight of pavement = 24Soil cover = 0 mm
::LOADING
HB wheel load = 62.5 kN/wheel NORMALLY USE 25 UNIT HB = 45*2.5=62.5KN/WHEEL
Max.coefficient of lateralearth pressure = 0.6
Min.coefficient of lateralearth pressure = 0.2
PARTIAL FACTOR OF SAFETY
(BASED ON BS5400:PART 2)
Dead load (concrete) = 1.15Superimposed dead load = 1.75HB Highway load = 1.30Earth pressure = 1.50ULS for concrete = 1.15
MATERIAL PROPERTIES
fcu = 30 fy = 460
::
kN/m3
kN/m3
kN/m3
N/mm2
N/mm2
document.xls 2
BOX CULVERT ANALYSIS
UNFACTORED LOAD
Self weight of top slab = 5.52Weight of walls = 7.56Weight of pavement = 2.16Weight of soil cover = 0.00HB Highway load = 85.61
*Note: Dispersion of wheel load is taken as 2:1 in soil (BS5400 :pt 2) For depth of fill 6.0m > depth > 1.8m , consider 2 axles only
L = 1.89 m (longitudinal dispersion) B = 3.09 m (transverse dispersion)
ANALYSIS OF BOX (A) CASE 1 : For max.BM and shear on wall & max. hogging
BM at corners, consider max. lateral earth pressure acting on the wall in empty condition.
P1 ------> ! A where ! P1, P2 = earth pressure ! !
P2 ------> ! B
P1 = 22.93
P2 = 48.39
Top slab pressure = 139.64
Base pressure = 149.64::
Loading is symmetrical about the vertical centrelineof the box.
-FEM(AD) = 17.61 kNm/m FM(AD) = 26.41 kNm/m FEM(AB) = 4.17 kNm/m-FEM(BA) = 4.82 kNm/m FM(AB) = 6.74 kNm/m FEM(BC) = 18.87 kNm/m FM(BC) = 28.30 kNm/m
Moment distribution (case 1): distribution factor ,
DF(AD) = DF(BC) = 0.33 I(slab) = 1013916667 mm4DF(AB) = DF(DC) = 0.67 I(wall) = 1013916667 mm4
Joints A BAD AB BA BC
DF 0.33 0.67 0.67 0.33 FEM -17.6 4.2 -4.8 18.9
4.5 9.0 -9.4 -4.7-4.7 4.5
1.6 3.1 -3.0 -1.5-1.5 1.6
0.5 1.0 -1.0 -0.5-0.5 0.5
0.2 0.3 -0.3 -0.2--------------------------------------------------------------------------------------------
-10.9 10.9 -12.0 12.0--------------------------------------------------------------------------------------------
:: (B) CASE 2 : For max.sagging moment in the top & bottom
slab, consider min.lateral earth pressure acting on the box.
P1 = 7.64
P2 = 16.13
FEM(AB) = 1.39 kNm/m FM(AB) = 2.25 kNm/m -FEM(BA) = 1.61 kNm/mMoment distribution (case 2): Joints A B
AD AB BA BC DF 0.33 0.67 0.67 0.33 FEM -17.6 1.4 -1.6 18.9
5.4 10.8 -11.5 -5.8-5.8 5.4
1.9 3.8 -3.6 -1.8-1.8 1.9
0.6 1.2 -1.3 -0.6-0.6 0.6
0.2 0.4 -0.4 -0.2---------------------------------------
-9.5 9.5 -10.5 10.5---------------------------------------
kN/m2
kN/m2
kN/m2
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kN/m2
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document.xls 3
DESIGN MOMENT ENVELOPEHogging moment at bottom corners = 12.00 kNm/m 12.00
Hogging moment at top corners = 10.90 kNm/m 10.90
Sagging moment at top slab = 16.94 kNm/m 16.94
Sagging moment at bottom slab = 17.83 kNm/m 17.83
Hogging moment of wall = 4.71 kNm/m -4.71SHEAR
cover to rebar = 50 mmsize of rebar = 12 mm dia. for Slab.
10 mm dia.for Wall.Critical shear section is at distance 2*d from theface of support.Shear in base slab : Effective depth, d = 174 mm Shear V = 22.75 kN/mShear in wall : Effective depth, d = 175 mm R1" = 6.44
P3' = 38.76 Shear V = 5.18 kN/m P3" = 12.92
REINFORCEMENT DESIGNHogging Steel at Bottom Corners :(i) Slab
K = 0.013216776 < 0.156No comp.steel required. Z = 171.41 > 165.3As(req)= 181
(ii) wall K = 0.013066158 < 0.156No comp.steel required. Z = 172.42 > 166.25As(req)= 180
Hogging Steel at Top Corners :(i) Slab
K = 0.01199689 < 0.156No comp.steel required. Z = 171.65 > 165.3As(req)= 165
(ii) wall K = 0.011860174 < 0.156No comp.steel required. Z = 172.66 > 166.25As(req)= 164
::Sagging Steel at Top Slab :
K = 0.018649174 < 0.156No comp.steel required. Z = 170.32 > 165.3As(req)= 256
Sagging Steel at Bottom Slab : K = 0.01962779 < 0.156No comp.steel required. Z = 170.12 > 165.3As(req)= 269
Hogging Steel in Wall : K = 0.005123193 < 0.156No comp.steel required. Z = 174.00 > 166.25As(req)= 71
Minimum Steel Ratio Required For Tension & Distribution Steel = 0.15% (i) Slab
As (min) = 261(ii) Wall
As (min) = 263
REINFORCEMENT PROVISION (A) SUPPORT STEEL
(I) TOP SLABuse Y 12 spacing 300 c/c As (req) = 261 As (prov) = 377
(II) BOTTOM SLABuse Y 12 spacing 300 c/c As (req) = 261 As (prov) = 377
(III) WALLuse Y 10 spacing 250 c/c As (req) = 263 As (prov) = 314
mm2/m
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document.xls 4
(B) MIDSPAN STEEL(I) TOP SLAB
use Y 12 spacing 300 c/c As (req) = 261 As (prov) = 377
::(II) BOTTOM SLAB
use Y 12 spacing 300 c/c As (req) = 269 As (prov) = 377
(III) WALL
use Y 10 spacing 250 c/c As (req) = 263 As (prov) = 314
SHEAR CHECK(i) Base Shear = 22.75 kN Shear stress v = 0.13
ps = 0.22 %vc = 0.50 * Shear is OK.
(ii) Wall Shear = 5.18 kN Shear stress v = 0.03
ps = 0.18 %vc = 0.47 * Shear is OK.
mm2/mmm2/m
mm2/mmm2/m
mm2/mmm2/m
N/mm2
N/mm2
N/mm2
N/mm2
document.xls 5
Kumpulan Jurutera Perunding PROJECT : PJE JOB NO : DESIGNED BY : ILLAHI DATE : 18-Apr-23
STRUCTURAL DESIGN OF BOX CULVERTS ( HB HIGHWAY LOAD )
CULVERT NO. : 1500m x 1500 with soil cover
INPUT DATA
DIMENSIONS OF R.C BOX
Internal width = 1500 mm A DInternal height = 1500 mmWall thickness = 230 mmSlab thickness = 300 mmEffective width = 1730 mmEffective height = 1800 mm B C
ASSUMPTIONS
Thickness of pavement = 110 mm
Unit weight of soil = 20Unit weight of concrete = 24Unit weight of pavement = 24Soil cover = 1000 mm
::LOADING
HB wheel load = 62.5 kN/wheel NORMALLY USE 25 UNIT HB = 45*2.5=112.5KN/WHEEL
Max.coefficient of lateralearth pressure = 0.6
Min.coefficient of lateralearth pressure = 0.2
PARTIAL FACTOR OF SAFETY
(BASED ON BS5400:PART 2)
Dead load (concrete) = 1.15Superimposed dead load = 1.75HB Highway load = 1.30Earth pressure = 1.50ULS for concrete = 1.10
MATERIAL PROPERTIES
fcu = 30 fy = 460
::
kN/m3
kN/m3
kN/m3
N/mm2
N/mm2
document.xls 6
BOX CULVERT ANALYSIS
UNFACTORED LOAD
Self weight of top slab = 7.20Weight of walls = 8.45Weight of pavement = 2.64Weight of soil cover = 20.00HB Highway load = 41.81
*Note: Dispersion of wheel load is taken as 2:1 in soil (BS5400 :pt 2) For depth of fill 6.0m > depth > 1.8m , consider 2 axles only
L = 2.91 m (longitudinal dispersion) B = 4.11 m (transverse dispersion)
ANALYSIS OF BOX (A) CASE 1 : For max.BM and shear on wall & max. hogging
BM at corners, consider max. lateral earth pressure acting on the wall in empty condition.
P1 ------> ! A where ! P1, P2 = earth pressure ! !
P2 ------> ! B
P1 = 42.98
P2 = 78.62
Top slab pressure = 99.27
Base pressure = 109.96::
Loading is symmetrical about the vertical centrelineof the box.
-FEM(AD) = 24.76 kNm/m FM(AD) = 37.14 kNm/m FEM(AB) = 15.45 kNm/m-FEM(BA) = 17.38 kNm/m FM(AB) = 24.62 kNm/m FEM(BC) = 27.42 kNm/m FM(BC) = 41.14 kNm/m
Moment distribution (case 1): distribution factor ,
DF(AD) = DF(BC) = 0.54 I(slab) = 2250000000DF(AB) = DF(DC) = 0.46 I(wall) = 1013916667
Joints A BAD AB BA BC
DF 0.54 0.46 0.46 0.54 FEM -24.8 15.5 -17.4 27.4
5.0 4.3 -4.7 -5.4-2.3 2.2
1.2 1.1 -1.0 -1.2-0.5 0.5
0.3 0.2 -0.3 -0.3-0.1 0.1
0.1 0.1 -0.1 -0.1---------------------------------------
-18.2 18.2 -20.5 20.5---------------------------------------
:: (B) CASE 2 : For max.sagging moment in the top & bottom
slab, consider min.lateral earth pressure acting on the box.
P1 = 14.33
P2 = 26.21
FEM(AB) = 5.15 kNm/m FM(AB) = 8.21 kNm/m -FEM(BA) = 5.79 kNm/mMoment distribution (case 2): Joints A B
AD AB BA BC DF 0.54 0.46 0.46 0.54 FEM -24.8 5.2 -5.8 27.4
10.5 9.1 -10.0 -11.6-5.0 4.6
2.7 2.3 -2.1 -2.4-1.1 1.2
0.6 0.5 -0.5 -0.6-0.3 0.2
0.1 0.1 -0.1 -0.1---------------------------------------
-10.9 10.9 -12.6 12.6---------------------------------------
kN/m2
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kN/m2
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document.xls 7
DESIGN MOMENT ENVELOPEHogging moment at bottom corners = 20.53 kNm/m 20.53
Hogging moment at top corners = 18.19 kNm/m 18.19
Sagging moment at top slab = 26.29 kNm/m 26.29
Sagging moment at bottom slab = 28.50 kNm/m 28.50
Sagging moment of wall = 5.26 kNm/m 5.26SHEAR
cover to rebar = 50 mmsize of rebar = 12 mm dia. for Slab.
12 mm dia.for Wall.Critical shear section is at distance 2*d from theface of support.Shear in base slab : Effective depth, d = 244 mm Shear V = 28.81 kN/mShear in wall : Effective depth, d = 174 mm R1" = 16.46
P3' = 69.45 Shear V = 27.09 kN/m P3" = 23.15
REINFORCEMENT DESIGNHogging Steel at Bottom Corners :(i) Slab
K = 0.011495478 < 0.156No comp.steel required. Z = 240.84 > 231.8As(req)= 221
(ii) wall K = 0.022605192 < 0.156No comp.steel required. Z = 169.51 > 165.3As(req)= 310
Hogging Steel at Top Corners :(i) Slab
K = 0.010182947 < 0.156No comp.steel required. Z = 241.21 > 231.8As(req)= 196
(ii) wall K = 0.020024176 < 0.156No comp.steel required. Z = 170.04 > 165.3As(req)= 275
::Sagging Steel at Top Slab :
K = 0.014717983 < 0.156No comp.steel required. Z = 239.94 > 231.8As(req)= 283
Sagging Steel at Bottom Slab : K = 0.015955668 < 0.156No comp.steel required. Z = 239.59 > 231.8As(req)= 307
Sagging Steel in Wall : K = 0.005795542 < 0.156No comp.steel required. Z = 172.87 > 165.3As(req)= 80
Minimum Steel Ratio Required For Tension & Distribution Steel = 0.15% (i) Slab
As (min) = 366(ii) Wall
As (min) = 261
REINFORCEMENT PROVISION (A) SUPPORT STEEL
(I) TOP SLABuse Y 12 spacing 300 c/c As (req) = 366 As (prov) = 377
(II) BOTTOM SLABuse Y 12 spacing 300 c/c As (req) = 366 As (prov) = 377
(III) WALLuse Y 12 spacing 300 c/c As (req) = 310 As (prov) = 377
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document.xls 8
(B) MIDSPAN STEEL(I) TOP SLAB
use Y 12 spacing 300 c/c As (req) = 366 As (prov) = 377
::(II) BOTTOM SLAB
use Y 12 spacing 300 c/c As (req) = 366 As (prov) = 377
(III) WALL
use Y 12 spacing 300 c/c As (req) = 261 As (prov) = 377
SHEAR CHECK(i) Base Shear = 28.81 kN Shear stress v = 0.12
ps = 0.15 %vc = 0.41 * Shear is OK.
(ii) Wall Shear = 27.09 kN Shear stress v = 0.16
ps = 0.22 %vc = 0.50 * Shear is OK.
mm2/mmm2/m
mm2/mmm2/m
mm2/mmm2/m
N/mm2
N/mm2
N/mm2
N/mm2
document.xls 9
NORMALLY USE 25 UNIT HB = 45*2.5=112.5KN/WHEEL
document.xls 10
mm4mm4
document.xls 11
Kumpulan Jurutera Perunding PROJECT : PJE JOB NO : DESIGNED BY : ILLAHI DATE : 18-Apr-23
STRUCTURAL DESIGN OF BOX CULVERTS ( HB HIGHWAY LOAD )
CULVERT NO. : 1.950m x 3.500m with soil cover
INPUT DATA
DIMENSIONS OF R.C BOX
Internal width = 3500 mm A DInternal height = 1950 mmWall thickness = 250 mmSlab thickness = 350 mmEffective width = 3750 mmEffective height = 2300 mm B C
ASSUMPTIONS
Thickness of pavement = 110 mm
Unit weight of soil = 20Unit weight of concrete = 24Unit weight of pavement = 24Soil cover = 1000 mm
::LOADING
HB wheel load = 62.5 kN/wheel NORMALLY USE 25 UNIT HB = 45*2.5=62.5KN/WHEEL
Max.coefficient of lateralearth pressure = 0.6
Min.coefficient of lateralearth pressure = 0.2
PARTIAL FACTOR OF SAFETY
(BASED ON BS5400:PART 2)
Dead load (concrete) = 1.15Superimposed dead load = 1.75HB Highway load = 1.30Earth pressure = 1.50ULS for concrete = 1.10
MATERIAL PROPERTIES
fcu = 30 fy = 460
::
kN/m3
kN/m3
kN/m3
N/mm2
N/mm2
document.xls 12
BOX CULVERT ANALYSIS
UNFACTORED LOAD
Self weight of top slab = 8.40Weight of walls = 5.85Weight of pavement = 2.64Weight of soil cover = 20.00HB Highway load = 41.81
*Note: Dispersion of wheel load is taken as 2:1 in soil (BS5400 :pt 2) For depth of fill 6.0m > depth > 1.8m , consider 2 axles only
L = 2.91 m (longitudinal dispersion) B = 4.11 m (transverse dispersion)
ANALYSIS OF BOX (A) CASE 1 : For max.BM and shear on wall & max. hogging
BM at corners, consider max. lateral earth pressure acting on the wall in empty condition.
P1 ------> ! A where ! P1, P2 = earth pressure ! !
P2 ------> ! B
P1 = 43.47
P2 = 89.01
Top slab pressure = 100.79
Base pressure = 108.19::
Loading is symmetrical about the vertical centrelineof the box.
-FEM(AD) = 118.11 kNm/m FM(AD) = 177.17 kNm/m FEM(AB) = 27.20 kNm/m-FEM(BA) = 31.21 kNm/m FM(AB) = 43.80 kNm/m FEM(BC) = 126.79 kNm/m FM(BC) = 190.18 kNm/m
Moment distribution (case 1): distribution factor ,
DF(AD) = DF(BC) = 0.46 I(slab) = 3572916667DF(AB) = DF(DC) = 0.54 I(wall) = 1302083333
Joints A BAD AB BA BC
DF 0.46 0.54 0.54 0.46 FEM -118.1 27.2 -31.2 126.8
41.5 49.4 -51.9 -43.7-26.0 24.7
11.9 14.1 -13.4 -11.3-6.7 7.0
3.1 3.6 -3.8 -3.2-1.9 1.8
0.9 1.0 -1.0 -0.8---------------------------------------
-60.8 60.8 -67.8 67.8---------------------------------------
:: (B) CASE 2 : For max.sagging moment in the top & bottom
slab, consider min.lateral earth pressure acting on the box.
P1 = 14.49
P2 = 29.67
FEM(AB) = 9.07 kNm/m FM(AB) = 14.60 kNm/m -FEM(BA) = 10.40 kNm/mMoment distribution (case 2): Joints A B
AD AB BA BC DF 0.46 0.54 0.54 0.46 FEM -118.1 9.1 -10.4 126.8
49.8 59.2 -63.2 -53.2-31.6 29.6
14.4 17.2 -16.1 -13.5-8.0 8.6
3.7 4.4 -4.7 -3.9-2.3 2.2
1.1 1.3 -1.2 -1.0---------------------------------------
-49.1 49.1 -55.2 55.2---------------------------------------
kN/m2
kN/m2
kN/m2
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document.xls 13
DESIGN MOMENT ENVELOPEHogging moment at bottom corners = 67.78 kNm/m 67.78
Hogging moment at top corners = 60.77 kNm/m 60.77
Sagging moment at top slab = 128.07 kNm/m 128.07
Sagging moment at bottom slab = 135.02 kNm/m 135.02
Hogging moment of wall = 20.47 kNm/m -20.47SHEAR
cover to rebar = 50 mmsize of rebar = 12 mm dia. for Slab.
12 mm dia.for Wall.Critical shear section is at distance 2*d from theface of support.Shear in base slab : Effective depth, d = 294 mm Shear V = 125.72 kN/mShear in wall : Effective depth, d = 194 mm R1" = 22.48
P3' = 78.86 Shear V = 44.90 kN/m P3" = 26.29
REINFORCEMENT DESIGNHogging Steel at Bottom Corners :(i) Slab
K = 0.026138499 < 0.156No comp.steel required. Z = 285.20 > 279.3As(req)= 606
(ii) wall K = 0.060030484 < 0.156No comp.steel required. Z = 180.06 < 184.3As(req)= 941
Hogging Steel at Top Corners :(i) Slab
K = 0.023436077 < 0.156No comp.steel required. Z = 286.13 > 279.3As(req)= 544
(ii) wall K = 0.053824019 < 0.156No comp.steel required. Z = 181.61 < 184.3As(req)= 836
::Sagging Steel at Top Slab :
K = 0.049387571 < 0.156No comp.steel required. Z = 276.87 < 279.3As(req)= 1156
Sagging Steel at Bottom Slab : K = 0.052070637 < 0.156No comp.steel required. Z = 275.87 < 279.3As(req)= 1223
Hogging Steel in Wall : K = 0.018131083 < 0.156No comp.steel required. Z = 190.01 > 184.3As(req)= 278
Minimum Steel Ratio Required For Tension & Distribution Steel = 0.15% (i) Slab
As (min) = 441(ii) Wall
As (min) = 291
REINFORCEMENT PROVISION (A) SUPPORT STEEL
(I) TOP SLABuse Y 12 spacing 200 c/c As (req) = 544 As (prov) = 565
(II) BOTTOM SLABuse Y 12 spacing 175 c/c As (req) = 606 As (prov) = 646
(III) WALLuse Y 12 spacing 100 c/c As (req) = 941 As (prov) = 1131
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document.xls 14
(B) MIDSPAN STEEL(I) TOP SLAB
use Y 16 spacing 150 c/c As (req) = 1156 As (prov) = 1340
::(II) BOTTOM SLAB
use Y 16 spacing 150 c/c As (req) = 1223 As (prov) = 1340
(III) WALL
use Y 12 spacing 300 c/c As (req) = 291 As (prov) = 377
SHEAR CHECK(i) Base Shear = 125.72 kN Shear stress v = 0.43
ps = 0.22 %vc = 0.44 * Shear is OK.
(ii) Wall Shear = 44.90 kN Shear stress v = 0.23
ps = 0.58 %vc = 0.67 * Shear is OK.
mm2/mmm2/m
mm2/mmm2/m
mm2/mmm2/m
N/mm2
N/mm2
N/mm2
N/mm2
document.xls 15
NORMALLY USE 25 UNIT HB = 45*2.5=62.5KN/WHEEL
document.xls 16
mm4mm4
document.xls 17
Kumpulan Jurutera Perunding PROJECT : PJE JOB NO : DESIGNED BY : ILLAHI DATE : 18-Apr-23
STRUCTURAL DESIGN OF BOX CULVERTS ( HB HIGHWAY LOAD )
CULVERT NO. : 1.950m x 3.500m
INPUT DATA
DIMENSIONS OF R.C BOX
Internal width = 3500 mm A DInternal height = 1950 mmWall thickness = 250 mmSlab thickness = 350 mmEffective width = 3750 mmEffective height = 2300 mm B C
ASSUMPTIONS
Thickness of pavement = 110 mm
Unit weight of soil = 20Unit weight of concrete = 24Unit weight of pavement = 24Soil cover = 0 mm
::LOADING
HB wheel load = 62.5 kN/wheel NORMALLY USE 25 UNIT HB = 45*2.5=112.5KN/WHEEL
Max.coefficient of lateralearth pressure = 0.6
Min.coefficient of lateralearth pressure = 0.2
PARTIAL FACTOR OF SAFETY
(BASED ON BS5400:PART 2)
Dead load (concrete) = 1.15Superimposed dead load = 1.75HB Highway load = 1.30Earth pressure = 1.50ULS for concrete = 1.10
MATERIAL PROPERTIES
fcu = 30 fy = 460
::
kN/m3
kN/m3
kN/m3
N/mm2
N/mm2
document.xls 18
BOX CULVERT ANALYSIS
UNFACTORED LOAD
Self weight of top slab = 8.40Weight of walls = 5.85Weight of pavement = 2.64Weight of soil cover = 0.00HB Highway load = 84.17
*Note: Dispersion of wheel load is taken as 2:1 in soil (BS5400 :pt 2) For depth of fill 6.0m > depth > 1.8m , consider 2 axles only
L = 1.91 m (longitudinal dispersion) B = 3.11 m (transverse dispersion)
ANALYSIS OF BOX (A) CASE 1 : For max.BM and shear on wall & max. hogging
BM at corners, consider max. lateral earth pressure acting on the wall in empty condition.
P1 ------> ! A where ! P1, P2 = earth pressure ! !
P2 ------> ! B
P1 = 23.67
P2 = 69.21
Top slab pressure = 136.08
Base pressure = 143.48::
Loading is symmetrical about the vertical centrelineof the box.
-FEM(AD) = 159.46 kNm/m FM(AD) = 239.20 kNm/m FEM(AB) = 18.47 kNm/m-FEM(BA) = 22.48 kNm/m FM(AB) = 30.71 kNm/m FEM(BC) = 168.14 kNm/m FM(BC) = 252.20 kNm/m
Moment distribution (case 1): distribution factor ,
DF(AD) = DF(BC) = 0.46 I(slab) = 3572916667DF(AB) = DF(DC) = 0.54 I(wall) = 1302083333
Joints A BAD AB BA BC
DF 0.46 0.54 0.54 0.46 FEM -159.5 18.5 -22.5 168.1
64.4 76.6 -79.1 -66.6-39.5 38.3
18.1 21.5 -20.8 -17.5-10.4 10.7
4.7 5.6 -5.8 -4.9-2.9 2.8
1.3 1.6 -1.5 -1.3---------------------------------------
-70.9 70.9 -77.9 77.9---------------------------------------
:: (B) CASE 2 : For max.sagging moment in the top & bottom
slab, consider min.lateral earth pressure acting on the box.
P1 = 7.89
P2 = 23.07
FEM(AB) = 6.16 kNm/m FM(AB) = 10.24 kNm/m -FEM(BA) = 7.49 kNm/mMoment distribution (case 2): Joints A B
AD AB BA BC DF 0.46 0.54 0.54 0.46 FEM -159.5 6.2 -7.5 168.1
70.1 83.3 -87.2 -73.4-43.6 41.6
19.9 23.7 -22.6 -19.0-11.3 11.8
5.2 6.1 -6.4 -5.4-3.2 3.1
1.5 1.7 -1.7 -1.4---------------------------------------
-62.8 62.8 -68.9 68.9---------------------------------------
kN/m2
kN/m2
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DESIGN MOMENT ENVELOPEHogging moment at bottom corners = 77.89 kNm/m 77.89
Hogging moment at top corners = 70.88 kNm/m 70.88
Sagging moment at top slab = 176.35 kNm/m 176.35
Sagging moment at bottom slab = 183.31 kNm/m 183.31
Hogging moment of wall = 43.67 kNm/m -43.67SHEAR
cover to rebar = 50 mmsize of rebar = 12 mm dia. for Slab.
12 mm dia.for Wall.Critical shear section is at distance 2*d from theface of support.Shear in base slab : Effective depth, d = 294 mm Shear V = 166.72 kN/mShear in wall : Effective depth, d = 194 mm R1" = 14.89
P3' = 59.06 Shear V = 32.28 kN/m P3" = 19.69
REINFORCEMENT DESIGNHogging Steel at Bottom Corners :(i) Slab
K = 0.030036503 < 0.156No comp.steel required. Z = 283.84 > 279.3As(req)= 697
(ii) wall K = 0.06898276 < 0.156No comp.steel required. Z = 177.77 < 184.3As(req)= 1095
Hogging Steel at Top Corners :(i) Slab
K = 0.027334081 < 0.156No comp.steel required. Z = 284.78 > 279.3As(req)= 634
(ii) wall K = 0.062776294 < 0.156No comp.steel required. Z = 179.36 < 184.3As(req)= 987
::Sagging Steel at Top Slab :
K = 0.068009612 < 0.156No comp.steel required. Z = 269.79 < 279.3As(req)= 1633
Sagging Steel at Bottom Slab : K = 0.070692677 < 0.156No comp.steel required. Z = 268.74 < 279.3As(req)= 1704
Hogging Steel in Wall : K = 0.038679304 < 0.156No comp.steel required. Z = 185.27 > 184.3As(req)= 592
Minimum Steel Ratio Required For Tension & Distribution Steel = 0.15% (i) Slab
As (min) = 441(ii) Wall
As (min) = 291
REINFORCEMENT PROVISION (A) SUPPORT STEEL
(I) TOP SLABuse Y 12 spacing 150 c/c As (req) = 634 As (prov) = 754
(II) BOTTOM SLABuse Y 16 spacing 100 c/c As (req) = 697 As (prov) = 2010
(III) WALLuse Y 12 spacing 100 c/c As (req) = 1095 As (prov) = 1131
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document.xls 20
(B) MIDSPAN STEEL(I) TOP SLAB
use Y 16 spacing 100 c/c As (req) = 1633 As (prov) = 2010
::(II) BOTTOM SLAB
use Y 16 spacing 100 c/c As (req) = 1704 As (prov) = 2010
(III) WALL
use Y 12 spacing 100 c/c As (req) = 592 . As (prov) = 1131
SHEAR CHECK(i) Base Shear = 166.72 kN Shear stress v = 0.57
ps = 0.68 %vc = 0.64 * Shear is OK.
(ii) Wall Shear = 32.28 kN Shear stress v = 0.17
ps = 0.58 %vc = 0.67 * Shear is OK.
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NORMALLY USE 25 UNIT HB = 45*2.5=112.5KN/WHEEL
document.xls 22
mm4mm4
