Samaila Consultant Limited

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SAMAILA CONSULTANT LIMITEDConsulting Engineers & Planners1c Collage RoadKaduna

CULVERT No. CV 9 (2 x 2 Single Box Culvert)

LOCATION 15 + 548

DATE June.04

DESIGN CODES:

1. BS 8110 : Part 1, 1985

2. BS 5400 : Part 2, 1989

SOIL PARAMETER:

Allowable Bearing Capacity 200

DESIGN DATA:

Strength of Concrete, Fcu 25

Strength of Steel, Fy 410

Weight of Concrete 24

Weight of Soil (Filling) 18

Weight of Asphalt 23

kN/m2

N/mm2

N/mm2

gconc kN/m3

gsoil kN/m3

gasph kN/m3

Samaila Consultant Limited

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Ta= 100

f= 7200

d= 300

2300 .=hH= 2000

b= 300

t= 300 2000 300

B= 2300

BS 5400:Part 2 LOADINGSTable 1

1.15 For Self Weight of Culvert

1.50 For Earthfill

1.50 For HA Vehicle

1.30 For HB Vehicle

1.00 For Asphalt

DEAD LOAD

1 For Top Slab .= .= 8.28

2 For Bottom Slab .= .= 8.28

3 For Walls .= .= 12.74

4 Weight of Fill .= .= 194.40

5 Weight of Asphalt .= .= 2.30Total Dead Load =

TOTAL 226.00 226

IMPOSED LOAD

BS 5400: 1 Stresses due to HA Vehicle, Part 2 P=100 kNClauses6.2.56.2.6and 2:1 340 72006.4.1.5

2300

2300

Contact Length = 7540 mm

P/ (Contact Area)

.= 1.7589654469 1.76

gf1 =

gf2 =

gf3 =

gf4 =

gf5 =

gf1 (d gconc) kN/m2

gf1 (b gconc) kN/m2

gf1 (2 t Hgconc) kN/m2

gf2 (f gsoil) kN/m2

gf5 (Ta gasph) kN/m2

kN/m2 kN/m2

sHA

sHA =

sHA =

kN/m2 kN/m2

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BS 5400: 2 Stresses due to HB Vehicle, Part 2Clauses6.3.16.3.2 1.8m 6m 1.8mand6.3.3 A

7200 2:1 361

2300

2300

A

P P P P1m 1m 1m

7200

2300

SECTION A-A

Assuming 45 Units HB Vehicle, then the Load Per Axle is 450 kN

Contact Width = 7561 mm

Contact Length = 10561 mm

BS 5400: 450 / (Contact Area)

Part 2

Clause .= 5.6354452273 5.646.2.7

HB Loading > HA Loading

Design Load =Design Load =

.= 7.3260787955 7.33

EARTH PRESSURE ON WALLSBS 5400:

Part 2 f = 30 degClause

5.8.1

.= 0.33333333

sHB

sHB =

sHB =

kN/m2 kN/m2

gf4 sHB

kN/m2 kN/m2

Ka = 1 - sinf

1 + sinf

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H2 =7200

H1 =9500

2300

2300

At the Bottom of the Culvert

q2 =

.= 85.5 85.5

q1 =

.= 64.8 64.8

HYDROSTATIC PRESSURE

20

SURCHARGE PRESSURE

H1 =9500

q3

Ka(Load due to Vehicle + Fill)q3 =

.= 67.2420263 67.2

CHECKING SOIL BEARING CAPACITY

Allowable Soil Bearing Capacity = 200

Total Load on the Soil = (Dead Load + Imposed Load)

.= 233.32454033

q1

q2

q2 = KaH1gsoilgf2

kN/m2 kN/m2

q1 = KaH2gsoilgf2

kN/m2 kN/m2

Pw = gw h = kN/m2

q3 =

kN/m2 kN/m2

kN/m2

kN/m2

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ANALYSIS OF FORCESTotal Bending Pressure on Members

Top Slab = [ Slab Wt + Fill + Asphalt + HB] = 212.31

Bottom Slab = [ Top Slab Wt + Base Wt + Walls Wt] = 233.32

132

152.74

212.306

132 132A B

D C152.7 152.74

233.325

h = 2.3 m 0.3 m

L = 2.3 m 0.3 m

1

2

3

4

13

5

7

9

11

kN/m2

kN/m2

Side Walls, q1 = [ q1 + Surchage Pressure] = kN/m2

q2 = [ q2 + Surchage Pressure] = kN/m2

ts =

tw =

N = [h/L] [ts/tw]3 =

N1 = N + 1 =

N2 = N + 2 =

N3 = N + 3 =

N4 = 4N + 9 =

N5 = 2N + 3 =

N6 = N + 6 =

N7 = 2N + 7 =

N8 = 3N + 8 =

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212.31

-46.80 kNm

Moments due to weight of walls

22.15

1.22 kNm

-6.10 kNm

85.50

-8.48 kNm

-10.37 kNm

67.24

-14.82 kNm

20.00

1.98 kNm

2.42 kNm

20

9.92 kNm

4.35 kNm

SUMMATION OF MOMENTS

Case 1: culvert empty

-68.88 kNm

-78.09 kNm

Case 1: culvert empty

-58.96 kNm

-73.73 kNm

Moments due to roof loads [ q = kN/m2]

MA = MB = MC = MD = [ -qL2/12N1] =

q = [2G]/[1 + tw] = kN/m2

MA = MB = [ +qL2N/12N1N3] =

MC = MD = [ -N5/N]MA =

Moments due to earth pressure [ q = kN/m2]

MA = MB = [ -qh2NN7/60N1N3] =

MC = MC = [N8/N7]MA =

Moments due to surcharge pressure[ q = kN/m2]

MA = MB = MC = MD = [ -qh2N/12N1] =

Moments due to hydrostatic pressure[ q = kN/m2]

MA = MB = q[h2NN7/60N1N3] =

MC = MD = [N8/N7]MA =

Moments due to excessive hydrostatic internal pressure[ q = kN/m2]

MA = MB = q[h2NN3+L2N5]/[12N1N3] =

MC = MD = qN[h2N3-L2]/[12N1N3] =

MA = MB =

MC = MD =

MA = MB =

MC = MD =

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Moments At The Spans

(i) Spans AB 212.31

A B68.8768235 2.3 68.877

244.15 kN

244.15 kN

x = 1.15 m

71.51 kNm

(Ii) Spans CD233.32

C D78.0860014 2.3 78.086

268.32 kN

268.32 kN

x = 1.15 m

76.20 kNm

(iii) Spans AD & BC

20.7 9 x132.042

D,C A,B73.73 2.3 68.877

y = 9

161.89 kN

165.61 kN

x = 0.64 m (From C)

7.38 kNm

Bending Moment Diagram

68.8768

68.88

71.51

7.38 7.38

76.2078.09

RA =

RB =

Mmax =

RC =

RD =

Mmax =

RA =

RF =

Mmax =

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DESIGN OF WINGWALLS

C1400

1900 F300300 C h/3

300 5700L= 6000 q

Force due to Earth Pressure on the Walls is given by:

23.805 kN

This Force is acting at h/3 from the base of the wall

Design Moment, M is given by M = F(h/3) =

18.2505 kNm

K = 0.01 z = 237.5 mm

215.43

Base Slabs of Wing Walls

The upward Pressure at the base slab is:

q = (self wt of the slab) = 7.2

32.4 kNm

K = 0.020736 z = 237.5 mm

As = 382.453189

DESIGN OF REINFORCEMENT cover = 40 mmd = 250 mm

TOP SLAB REINFORCEMENTSupport Midspan

Moment M, (kNm) 68.88 71.51

K 0.04 0.05

Z 237.50 237.50

813.03 844.12

R20 @ 200mm R20 @ 200mm

BOTTOM SLAB REINFORCEMENT

Support Midspan

Moment M, (kNm) 78.09 76.20

K 0.05 0.05

Z 237.50 237.50

921.74 899.47

R20 @ 200mm R20 @ 200mm

Distribution Bars

390

Provide R16 @ 200mm c/c

F = gf[0.5Kagsoil h2] =

As =

Provide R16 @ 200mm c/c (1005mm2)

kN/m2

Midspan Moment = ql2/8 =

Provide R16 @ 200mm c/c (1005mm2)

AS

(1571mm2) (1571mm2)

AS

(1571mm2) (1571mm2)

Area of steel required, As = 0.13%bh = mm2