Single Box Culvert Structural Design 1.5m x 1.5m.xls

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document.xls 1 Kumpulan Jurutera Perunding PROJECT : PJE JOB NO : DESIGNED BY : ILLAHI DATE : 11-Mar-22 STRUCTURAL DESIGN OF BOX CULVERTS ( HB HIGHWAY LOAD ) CULVERT NO. : 1.500m x 1.500m INPUT DATA DIMENSIONS OF R.C BOX Internal width = 1500 mm A D Internal height = 1500 mm Wall thickness = 230 mm Slab thickness = 300 mm Effective width = 1730 mm Effective height = 1800 mm B C ASSUMPTIONS Thickness of pavement = 110 mm Unit weight of soil = 20 Unit weight of concrete = 24 Unit weight of pavement = 24 Soil 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 lateral earth pressure = 0.6 Min.coefficient of lateral earth pressure = 0.2 PARTIAL FACTOR OF SAFETY (BASED ON BS5400:PART 2) Dead load (concrete) = 1.15 Superimposed dead load = 1.75 HB Highway load = 1.30 Earth pressure = 1.50 ULS for concrete = 1.10 MATERIAL PROPERTIES fcu = 30 fy = 460 :: kN/m 3 kN/m 3 kN/m 3 N/mm 2 N/mm 2

Transcript of Single Box Culvert Structural Design 1.5m x 1.5m.xls

Page 1: Single Box Culvert Structural Design 1.5m x 1.5m.xls

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Kumpulan Jurutera Perunding PROJECT : PJE JOB NO : DESIGNED BY : ILLAHI DATE : 18-Apr-23

STRUCTURAL DESIGN OF BOX CULVERTS ( HB HIGHWAY LOAD )

CULVERT NO. : 1.500m x 1.500m

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 = 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 = 1.10

MATERIAL PROPERTIES

fcu = 30 fy = 460

::

kN/m3

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BOX CULVERT ANALYSIS

UNFACTORED LOAD

Self weight of top slab = 7.20Weight of walls = 8.45Weight 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 = 23.18

P2 = 58.82

Top slab pressure = 134.56

Base pressure = 145.25::

Loading is symmetrical about the vertical centrelineof the box.

-FEM(AD) = 33.56 kNm/m FM(AD) = 50.34 kNm/m FEM(AB) = 10.11 kNm/m-FEM(BA) = 12.03 kNm/m FM(AB) = 16.60 kNm/m FEM(BC) = 36.23 kNm/m FM(BC) = 54.34 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 -33.6 10.1 -12.0 36.2

12.6 10.9 -11.2 -13.0-5.6 5.4

3.0 2.6 -2.5 -2.9-1.3 1.3

0.7 0.6 -0.6 -0.7-0.3 0.3

0.2 0.1 -0.1 -0.2---------------------------------------

-17.1 17.1 -19.5 19.5---------------------------------------

:: (B) CASE 2 : For max.sagging moment in the top & bottom

slab, consider min.lateral earth pressure acting on the box.

P1 = 7.73

P2 = 19.61

FEM(AB) = 3.37 kNm/m FM(AB) = 5.53 kNm/m -FEM(BA) = 4.01 kNm/mMoment distribution (case 2): Joints A B

AD AB BA BC DF 0.54 0.46 0.46 0.54 FEM -33.6 3.4 -4.0 36.2

16.2 14.0 -15.0 -17.3-7.5 7.0

4.0 3.5 -3.3 -3.8-1.6 1.7

0.9 0.8 -0.8 -0.9-0.4 0.4

0.2 0.2 -0.2 -0.2---------------------------------------

-12.3 12.3 -14.1 14.1---------------------------------------

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DESIGN MOMENT ENVELOPEHogging moment at bottom corners = 19.49 kNm/m 19.49

Hogging moment at top corners = 17.15 kNm/m 17.15

Sagging moment at top slab = 38.05 kNm/m 38.05

Sagging moment at bottom slab = 40.26 kNm/m 40.26

Hogging moment of wall = 1.71 kNm/m -1.71SHEAR

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 = 38.05 kN/mShear in wall : Effective depth, d = 174 mm R1" = 10.52

P3' = 49.65 Shear V = 18.44 kN/m P3" = 16.55

REINFORCEMENT DESIGNHogging Steel at Bottom Corners :(i) Slab

K = 0.01091206 < 0.156No comp.steel required. Z = 241.00 > 231.8As(req)= 210

(ii) wall K = 0.021457933 < 0.156No comp.steel required. Z = 169.75 > 165.3As(req)= 295

Hogging Steel at Top Corners :(i) Slab

K = 0.009599529 < 0.156No comp.steel required. Z = 241.37 > 231.8As(req)= 185

(ii) wall K = 0.018876917 < 0.156No comp.steel required. Z = 170.27 > 165.3As(req)= 259

::Sagging Steel at Top Slab :

K = 0.021304116 < 0.156No comp.steel required. Z = 238.08 > 231.8As(req)= 410

Sagging Steel at Bottom Slab : K = 0.022541801 < 0.156No comp.steel required. Z = 237.73 > 231.8As(req)= 434

Hogging Steel in Wall : K = 0.001885974 < 0.156No comp.steel required. Z = 173.63 > 165.3As(req)= 26

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) = 295 As (prov) = 377

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(B) MIDSPAN STEEL(I) TOP SLAB

use Y 12 spacing 250 c/c As (req) = 410 As (prov) = 452

::(II) BOTTOM SLAB

use Y 12 spacing 250 c/c As (req) = 434 As (prov) = 452

(III) WALL

use Y 12 spacing 300 c/c As (req) = 261 As (prov) = 377

SHEAR CHECK(i) Base Shear = 38.05 kN Shear stress v = 0.16

ps = 0.15 %vc = 0.41 * Shear is OK.

(ii) Wall Shear = 18.44 kN Shear stress v = 0.11

ps = 0.22 %vc = 0.50 * Shear is OK.

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NORMALLY USE 25 UNIT HB = 45*2.5=62.5KN/WHEEL

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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

::

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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---------------------------------------

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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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(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.

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NORMALLY USE 25 UNIT HB = 45*2.5=112.5KN/WHEEL

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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

::

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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---------------------------------------

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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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(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.

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NORMALLY USE 25 UNIT HB = 45*2.5=62.5KN/WHEEL

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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

::

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N/mm2

N/mm2

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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---------------------------------------

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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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(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

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mm4mm4