Retaing Wall Design

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PROJECT : CLIENT:

CONSULTANATS: Component:

DESIGN OF CANTELEVER RETAINING WALL (GUIDE WALLS) The design of wall is done based on following design parameters: 1 ] Top elevation of retaining wall 887.500 m 2 ] Bed level of retaining wall 870.000 m

3 ] Top width of training wall 1.500 m

4 ] bed width of wall 3.000 m

5 ] Calculated bed width 2.550 m

6 ] Slope of wall 0.086 h:1v

7 ] Unit weight of concrete 2.500 t/cum.

8 ] RLof backfill material 887.500 m

9 ] Saturation /Water level 887.500 m

10 ] Minimum water level away from fill 0.000 m 11 ] Moist density of earth backfill 1.900 t/cum 12 ] Saturated density of earth backfill 2.000 t/cum 13 ] Angle of internal friction of backfill 30.00 °

14 ] Surcharge on backfill 1.000 t/sq.m

15 ] Friction angle betwnwall and backfill 10.00° 16 ] ---do--- [for saturated backfill] 5.00° 17 ] Horizontal earth quake coefficient 0.160 18 ] Vertical earth quake coefficient 0.080

19 ] Unit weight of water 1.000 t/cum

20 ] Slope of earth fill 0.00°

21 ] Deepest bed level 870.000 m

22 ] Bearing capacity of soil 70.000 t/sq.m

23 ] Concrete Grade: M 20.00

24 ] Permissible strength of concrete 70.000 kg/sq.cm 25 ] Permissible strength in steel 2300.000 kg/sq.cm 26 ] - do - water ret structures 1900.000 kg/sq.cm 27 ] Friction between foundation and wall base 30.000 t/sq.m 28 ] Coeff of friction 45.00 ° 1.000

29 ] m 13.333

30 ] i 0.289

31 ] j 0.904

32 ] MMoment of resistanceQbd2 9.131 bd2 kg/sq.cm 33 ] Percentage of relief in drainage holes 50%

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34 ] Bed width of stem 3.000 m 35 ] Alpha-angle betn wall & vertical plane 4.90 ° 36 ] Depth of saturation from bed level 17.500 m 37 ] Height of soil above saturation level 0.000 m 38 ] Height of sat level aboveDBL 15.000 m

39 ] Height of soil above BL 17.500 m

40 ] Base width of the wall 10.000 m

41 ] Base width of the wall adopted 10.000 m

42 ] Toe projection required 2.200 m

43 ] Toe projection adopted 4.000 m

44 ] Heel length provided 3.000 m

45 ] Assume thickness 1.460 m

46 ] Thickness of base slab 2.500 m

47 ] Clear height 15.000 m

48 ] Horizontal force 117.905 t

49 ] Moment 589.523 t-m

50 ] Thickness of stem 254.092 cm

51 ] Assuming 16mm bars the overall thickness 300.000 cm

52 ] Effective depth 293.400 cm 53 ] FILLET SIZE 1.000 x 0.00 m 1.50 m Fill Side 6.00 m Heel 3.00 m 3.00 m 4.00 m Toe 2.50 m 10.00 m

The value of l is given by,

(

)

l a a = ± é ë ê ù û ú -tan . 1 1 0 5

(

)

l a a = -æ è ç ö_ø÷ æ è ç ç ç ç ö ø ÷ ÷ ÷ ÷ ± é ë ê ê ê ê ê ù û ú ú ú ú ú -tan . 1 1 1 0 5 w w s s

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for saturated condition,

l rad. deg.

For dry backfill 0.147 8.424 For sat.backfill 0.288 16.498

The coefficient of active earth pressure is calculated and as listed below.

dry-backfill

sat.

backfill

dry-backfill+e

q

sat-backfill+e

q

l

[deg]=

0.0000

8.4236

16.4977

COS(

F-a-l

)

2

=[A]

0.8200

0.9176

0.9776

COS(

l

)=[B]

1.0000

0.9892

0.9588

COS(

a

)

2

=[C]

0.9927

COS(

d+a+l

)=[D]

0.9664

0.9851

0.9183

0.8957

SIN(

F+d

)=[E]

0.6428

0.5736

0.6428

0.5736

SIN(

F

-

y

-

l

)=[F]

0.5000

0.3677

0.2335

COS(

a

-

y

)=[G]

0.9963

[B] X [C] X [D] =

0.9593

0.9779

0.9018

0.8526

[ 1 / (1 + ([E] X [F]/[D] X [G])^.5))^2)

0.4017

0.4214

0.4396

0.5195

Coeff.=K=

0.343

0.353

0.447

0.596

1 ] Coefficient of earth pressure

for dry / moist condition Km 0.3434

for saturated backfill Ks 0.3533

(

)

l a a = -æ è ç ö ø ÷ æ è ç ç ç ç ö ø ÷ ÷ ÷ ÷ ± é ë ê ê ê ê ê ù û ú ú ú ú ú -tan . 1 1 1 0 5 w w s s

(

)

(

) (

)

2 2 1 2 2

)

(

1

1 )

(

Cos

)

(

)

1 (

ú

û

ù

ê

ë

é

÷÷

ø

ö

çç

è

æ

+

-+

+

-±

=

l

a

d

y

a

l

y

f

d

f

l

a

d

a

l

a

l

f

a

Cos

Sin

Cos

C

_a _v

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for dry/moist backfill [with E.Q] Kme 0.4473

for saturated backfill [with E.Q] Kse 0.596

moments about toe

SL. V H L.A M

NO. t t m t-m

I Self weight of wall (1)= 56.250 4.750 267.19

(2)= 28.125 4.500 126.56 (3)= 62.500 5.000 312.50 TOTAL 146.875 706.25 II UPLIFT: Uplift force -10.00 m -87.500 3.333 -291.67 17.50 m -87.500 -291.67

III HORIZONTAL WATER PRESSURE -76.56 5.833 -446.61

IV EARTH PRESSURE

Total earth pressure on wall -83.919

Horizontal component - -82.67 6.042 -499.50

Vertical component 14.427 - 6.482 35.81

Weight of soil on heel slab

Dry/moist weight of soil=Vd 0.000 8.500 0.00

Weight of saturated soil=Vsat 90.000 8.500 765.00

Total 163.802 -159.23 269.27

EFFECT OF EARTH QUAKE On wall a) Horizontal component

(1)= -7.907 8.750 -69.19 (2)= -3.021 5.833 -17.63 DETAILS 2 1 3

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(3)= -1.286 0.000 -3.86 Total -12.214 -90.67 b) Vertical component (1)= -3.954 4.750 -18.78 (2)= -1.511 4.500 -6.80 (3)= -0.643 5.000 -3.21 Total -6.107 -28.79 On earth pressure

Dynamic increment of Earth pressure

a) For moist/dry backfill 0.312 b) For saturated backfill 0.727 HT.of B.L above D.B.L c = 0.000

Earth pressure due to dry/moist backfill 0.000 0.000

Earth pressure due to saturated backfill -46.747 -350.599

Total -6.107 -58.961 -470.061

DETAILS UNIT STATIC DYNAMIC

SV t 163.802 157.695 SH t -159.232 -218.193 SM t-m 269.273 -200.787 LEVER ARM m 1.644 -1.273 ECCENTRICITY m 3.356 6.273 NORMAL STRESS t/sq.m 16.380 15.769 BENDING STRESS t/sq.m 32.984 59.356 STRESS AT [HEEL] t/sq.m -16.604 -43.586 STRESS AT [TOE] t/sq.m 49.364 75.125 < S.B.C- HENCE OKAY FACTOR OF SAFETY[O.T] 1.218 1.218 FACTOR OF SAFETY [SLD] 2.913 2.098

point of zero pressure= 2.517 m from heel 3.672 m from heel

Distance from toe= 7.483 m 6.328 m

Stress at B= 3.187 t/sq.m -5.239 t/sq.m Stress at G= 22.977 t/sq.m 27.641 t/sq.m

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STRESS DIAGRAM(STATIC CONDITION)

STRESS DIAGRAM(EARTH QUAKE EFFECT CONDITION)

heel

toe 4.000 3.000 3.000 Fill side

Static(t/sq.m) 49 .4 #### 3. 2 -17 E.Q.(t/sq.m) 75 .1 #### -5. 2 -44 Intensity of pressur at B 22.977 t/sq.m Intensity of pressur at G 3.187 t/sq.m

DESIGN OF TOE SLAB

Self weight of slab 6.250 t/sq.m

Net upward pressure at D 43.114 t/sq.m

Net upward pressure at B 16.727 t/sq.m

Bending moment at B 174.186 t-m Effective depth 138.117 cm Overall depth 225.000 cm C F _E D B G -16.60 t/m² 0. 00 m 10 .0 0 m -43.59 t/m² 75.13 t/m² 0 .0 0 m 1 0 .0 0 m

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Depth provided 225.000 cm Effective depth 220.000 cm Area of steel 46.108 sq.cm Min steel 0.200 % 45.000 sq.cm Dia of bar 16.000 mm Area of bar 2.011 sq.cm spacing is 4.361 cm

Spacing provided (A) 16 mm @ 25 mm c/c

Area of steel provided=Ast= 80.425 sq.cm

Percentage of steel= 0.357 %

Distribution steel 11.250 sq.cm

Dia of bar 12 mm

spacing is 10.053 cm

Spacing provided (B) 12 mm @ 105 mm c/c

CHECK FOR SHEAR

Thickness of slab at the end (B) 225.000 cm Thickness of slab at the (Z-Z') 168.750 cm

Stress at (Z-Z') 31.982 t/sq.m

S.F. to be interpolated for tension condn. 41.004 t

Shear stress 2.430 kg/sq.cm 24.299 t/sq.m Ast/bd= 0.357 % Critical shear 2.692 kg/sq.cm <Tc, HENCE OKAY 0.31 m

With provision of fillet depth= 268.750 cm

Stress at (Z-Z') 25.385 t/sq.m Shear force= 11.680 t

Z'

Z

b

A

B

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Shear stress 0.043 kg/sq.cm

Ast/bd= 0.357 %

Add min area of steel for fillet 0.000 %

Total Steel 0.357

Critical shear 2.692 t/sq.m

<Tc, HENCE OKAY

DESIGN OF HEEL SLAB 31.25 t/sq.m

-16.60 t/sq.m

##### 3.19 t/sq.m

Downward pressure due to soil & self wt of slab= 31.250 t/sq.m Pressure on the heel slab (G) 3.187 kg/sq.cm Pressure on the heel slab (E) -16.604 t/sq.m

Net pressure at G 28.063 t/sq.m Net pressure at E 47.854 t/sq.m Total force 113.876 t L1 1.500 m L2 1.000 m M1= 126.29 M2= 29.686 155.971 t-m B.M. at G 155.971 t-m d= 130.696 cm

Provide effective depth of 220.000 cm

Overall depth including fillet 400.000 cm

Area of steel 22.995 sq.cm

Min steel= 0.120 %= 48.000 sq.cm

Area of steel considered= 48.000 sq.cm

Dia of bar 25 mm Ast= 4.909 sq.cm

Spacing with 1 no. of rows= 10.227 cm

Area of steel provided= 25 mm @ 100 mm

Area of steel provided=Ast= 49.087 sq.cm

Percentage of steel= 0.223 %

E

G

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Distribution steel 11.000 sq.cm

Dia of bar 16.000 mm

Area of steel 2.011 sq.cm

spacing is 18.278 cm

Spacing provided 16 mm @ 180 mm

CHECK FOR SHEAR

Thickness of fille= 100.000 cm Thickness of slab 400.000 cm Total depth= 500.000 cm S.F. 113.876 t Shear stress 2.278 kg/sq.cm Ast/bd= 0.223 %

Add min area of steel for fillet 0.100 %

Total percentage of Steel 0.323 %

Critical shear 2.658 kg/sq.cm

<Tc, HENCE OKAY

Bars should be carried in to the slab through adistance of

tbd 0.800

Ld=f fst/4tbd 179.688 cm 180.000 cm, To be extended in to the toe wall at top

H= 15.000

sl.no height area of

steel dia of bar No. of rows

spacing

required sp. adopted EL.

m cm2 mm cm cm m 0 0.000 0.000 16 1.000 887.500 Top of wall 1 1.500 0.334 16 1.000

602.12

25.000 886.000 2 3.000 2.449 16 1.000

82.108

25.000 884.500 3 4.500 7.629 16 1.000

26.356

25.000 883.000 4 6.000 16.792 16 1.000

11.974

11.500 881.500 5 7.500 30.610 16 1.000

6.569

6.500 880.000 6 9.000 49.587 16 1.000

4.055

4.000 878.500 7 10.500 74.111 16 1.000

2.713

2.500 877.000 8 12.000 104.481 16 1.000

1.924

1.500 875.500 9 13.500 140.933 16 1.000

1.427

1.000 874.000

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10 15.000 0.055 20 1.000

5703.625

25.000 872.500 Stem

Check For shear:

Shear force at the stem=

158.783

t

Area of steel=

12.566 sq.cm

Percentage of steel

0.042 %

Thickness of stem

3.000

m

Shear stress=

0.519

N/mm2

Permissible shear= 0.240 N/mm2 NOT OK

BOQ Unit Length= 100.00 m

SL.NO. ITEM UNIT QUANTITY RATE AMOUNT

A EXACAVATION CUM {35875.00}

1 IN SOIL {60.00%} CUM 21525.00 70.00 ##########

2 IN SOFT ROCK {30.00%} CUM 10762.50 110.00 ##########

3 IN ROCK {10.00%} CUM 3587.50 150.00 538125.00

BCONCRETE 3525.00 2500.00 ##########

C LEVELLING COURSE 0.15 M 150.00 1800.00 270000.00

D STEEL M.T 149.41 25000.00 ##########

E BACK FILLING CUM 28200.00 120.00 ##########

F Add for lea, lift, site clearance etc 5% 971528.14

Cost for 100m length 204.500 lakhs Rs= ##########

Cost/m length

2.045

lakhs

B BOQ OF RETAINING WALL

Wall Main bars No. of bars= 5.000 Height 3.500 Dia of bar 16.000 mm weight= 27.621 kg On both face= 55.242 kg Distribution No 18.000 L= 1.000 weight= 15.981 kg On both face= 31.961 kg

add 2.5% for laps & hooks etc: 2.180 kg

Total weight of steel: 89.383 kg

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Main bars: No. of bars= 11.000

Length= 3.000

Weight 127.161 kg

For top & bottom= 254.322 kg

Distribution:

No 18.000

Length= 1.000 m

Weight 28.410 kg

For top & bottom= 56.820 kg

add 5% for laps & hooks etc: 15.557 kg

Total weight of steel in heel slab: 326.699 kg

Toe slab:

Main bars:No. of bars= 41.000

Length= 7.000

Weight 452.982 kg

For top & bottom= 905.965 kg

Distribution:

No 68.000

Length= 1.000 m

Weight 60.371 kg

For top & bottom= 120.743 kg

add 5% for laps & hooks etc: 51.335 kg Total weight of steel in heel slab: 1078.043 kg

Total Steel = 1494.125 kg