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For Lectures,

assignments and

PDFsVisit Dr. Farouks Official Page

1

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SHEET PILE WALLS

Prepared By:

Prof. Dr. Ing. Farouk El-Kadi

Professor of Geotechincal Engineering

Faculty of Engineering

Ain Shams University

2

Shorouk

Academy

Faculty of Engineering

Civil Engineering Department

Course : Foundation Engineering 2

Fourth Year CivilYear : 2012

-

2013Version : 00

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USE OF SHEET PILING WALLS1. Water front construction

where other types of retainingwalls would requiredewatering of the site

2. Temporary constructionbecause of the high salvagevalue of sheet piles.

3. Construction at locationwhere the upper layer orlayers of subsoil areinadequate for supportingretaining walls.

4. As columns or piles.3

1. .2. . 3.

.4.

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1

. Water front construction

4

Ground surface

Water level

Sheet Pile

Sheet Pile with tie rod

Water level

Ground surface

Sheet Pile

Inclined tie (Pile)

Ground surface

Water level

Sheet Pile

Ground surface

W.L

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1


5

G.S

G.S

Sheet

Pile

Piles

SheetPile

SheetPile

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1


6 Bremen

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1. Water front construction

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(18)

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Coffer DamCable stay bridge

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2

T C i

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2. Temporary Construction

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Using sheet pile wall as a temporary structure

during subway excavation

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3. Weak Soil

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.

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4. As a column or a pile

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S.P.W Failure

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S.P.W Failure

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Sheet piling are not suitable for the following

cases

1. Very high walls whichrequire

disproportionatelyhigh flexural strengthof the pile section.

2. Inadequate depth ofpenetration due toboulders in the subsoilfor high bedrockwhich prevents pilepenetration.

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1. .2. .

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Problems of driving sheet piles Boulders or obstacles insub soil

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Common types and martial of sheet piles 1. Wood sheet piles.2. Concrete sheet piles.3. Pile used as a sheet pile wall.4. Steel sheet piles.

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Wood Sheet Piles

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Wood Sheet Piles

27DrivingDirection

DrivingDirection

DrivingDirection

DrivingDirection

Pile Tip

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Spiral Stirrups

Space for mortar

Normal steel RFT

Extra RFT for top part

Filling with mortar

Sec. A-B

Sec. C-D

Direction of Driving

Reinforced Concrete Sheet Piles

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Pile Used as a Sheet Piles

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Piles Used as a Sheet Piles

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Steel Sheet Pile

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Common Statical Types and Use of Sheet Piling

A. Statical Types

1. Cantilever sheet piling.

2. Anchored sheet piling. (Free Earth Support, Fixed

Earth Support)

3. Sheet piling with relieving platform.

B. Use of Sheet Piling1. Braced Cuts

2. Cellular Cofferdams

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2 0

S i l

l l i f h il

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2.0 Statical calculation for sheet pile

walls

The following are the different statical systems for sheetpile wall (Fig.1):

a- Cantilever S.P.W. (Fig. 1a).b- Anchored free S.P.W. (Fig. 1b).

c- Anchored fixed S.P.W. (Fig.1c).

There are different statical systems, such as maltyanchor S.P.W. fixed at the topetc.

We shall explain only the three types explained in (Fig.1) for different types of soil.

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2.1 The design procedure comprises the

following:

1. Assemble the general information: Topographical survey.

Elevation of top of wall.

Elevation of ground surface in front of the wall.

Max. water level, mean tide level and low water level.

2. Analyse the subsoil conditions:

Sufficient borings to get full information about soil properties in differentlevels and level of ground water (,,C).

Select the statical type of wall.

Compute earth pressure and surcharge pressure.

Determine the piling penetration.

Determine the bending stress and design the piling. Design the tie rods (for anchored S.P.W).

Design the anchorage (for anchored S.P.W).

Check total stability of sheet piles.

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following:

3. Lateral pressure acting on sheet piling walls A sheet piling wall may be subjected to some or all of the

following types of lateral pressure.

Earth pressure: active, at rest and passive pressure.

Lateral pressure due to surcharge load. Unbalanced water pressure and seepage pressure.

Mooring pull, ship impact, etc.

Earthquake force, wave pressure, etc.

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4. Earth pressure acting on sheet piling wall

Referring to earth pressure theory previously mentioned, Rankineand coulomb methods can only be used under following conditions:

a) Wall is rigid

b) Wall translates or rotates about its bottom. Distribution of earth pressure on a sheet pile wall is statically

indeterminate and a function of the deformation of sheet pile (Fig. 2).

Practically we can use Rankine and Coulomb theories.

For more accurate calculations we can use theories which take into

account the conditions of yield of the wall (Hansen, j. Brinch, 1953). We shall explain one of the new theories which consider the effect of

wall movement on the value of earth pressure

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following:

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2.2 Design of cantilever sheet pile wall

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There are different methods and theories for the statically calculation of

sheet pile wall. The main differences between the different methods are:

a-Calculation and distribution of earth pressure.

b-The method and assumptions for statically calculations.

The results needed from statically calculations are:

a- Penetration depth.

b- Max. bending moment.

c- Safe cross section for sheet bile.d- Deformation of sheet pile.

The cantilever sheet pile will be solved with the following methods:

a- Classical method.

i- Conventional.

ii- Simplified method.

b- Graphical method.

c- Blum method.

d- Sub grade reaction method.

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2.2 Design of cantilever sheet pile wall

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2.2.1 Cantilever sheet pile wall (Cohesionless soil Conventional method)

Assumptions:

a. Wall is rigid.

b. Rankine and Coulomb theories for E.P.

p2 =Kp Kad a p3 =h + dKp dKa = = + + ( + )

I. Calculation of penetration depth

Theory:

Penetration depth d = a+b (a = known,

b = unknown)

p2 , p3 = function of b

P2 , P3 = unknown

Required to find a relation between P2 ,

P3 and the unknown b

This can be done by using the equation

0i.e. P1+P3-P2=0 (1)

and dividing the area (O1 EOFA) to two

areas (O1GA, FOEGAF).

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(3A)

(3)

Equation (1) can be written as follows:1+ 3 2 = 0

3 =1

2(2+ 3)2 = 122.

1+ 122+ 3 1

22= 0

=

2 2

1/(

2+

3) (2)

The 2ndequilibrium equation is =

P1b + Z1 12 p2b b

3 + 1

2mp2+ p3 m3= 0

Substituting the value of (m) from equation (2)

P1+ 1 22

6 +(

2+

3)

6 2 2

12+ 3 2

= 0

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This equation can be written in the following form:

b4

+C1b3

-C2b2

-C3b-C4= 0 (4)

Where,

1 = 4( ) , 2 = 81( )C3 =

6P12KP KaZ1+ p4(KP Ka)

2

4 = 114 + 41( )2 4 = + ( )

Solve equation (4) by trial and error to determine b

d=b+a and required depth Dreq.=1.2 1.4d

C il h il ll (C h i l il C i l h d)

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I. Calculation of bending Moment

Steps to calculate bending moment:

1. The depth is known.

2. Draw the net earth pressure.

3. Divide the net earth pressure into strips (Fig.3). The area of every stripe will

act as a concentrated load in the C.G of the strip.

4. Calculate the moment at any section.

5. To calculate the max. bending moment, find the point of zero shear.

I. Design of section of sheet pile wall

From the value of max. bending and all stress of steel used choose the

section needed from the tables of standard section (example Table 1).

Rust effect must be taken into consideration (see table 2).

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47fig(3)

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*

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fig(4)

Divide the moment into different

concentrated elastic loads

Calculate the moment at point 0

The deflection = (Moment of the moment/EI)

Calculation of deflection

( bl 2) ff i h f d i i f l h ili

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Harbor bulkheads

(in./yr)

Beach bulkheads

(in./yr)

Groins and jetties

(in./yr)

Geographical location

South (south of welmington, N.C.) 0.0062 0.017 0.018

North (north of Pt. Pleasant, N.J.) 0.0023 0.0075 0.011

Zone relative to tidal planes

8 ft above mean high water 0.020

5 ft to 8 ft above mean high water 0.0049 0.022 0.010

2 ft to 5 ft above mean high water 0.0081

Mean high water 0.0027 0.0074 0.0055

Mean tide level 0.0024 0.004 0.024

Mean low water 0.0035 0.002 0.028

Mean low water to ground line Average of 4 values = 0.0036

Below ground line Average of 4 values = 0.0016

Exposure to salt spray

Heavy spray 0.0083 0.016 0.016

Moderate spray 0.0041 (beach bulkheads, groins, and jetties are

considered to be subjected to heavy spray)Light spray or none 0.0024

Paint protection

None 0.0045 0.018 0.020

At least painted once 0.0027 0.011 0.010

(Table 2) Factors affecting the rate of deterioration of steel sheet piling

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2.2.2 Cantilever sheet pile wall

(Cohesionless soil

simplified

method)

For equilibrium =

1

3 PP D0

Pa

3 H + Do = 0

PP =1

2KPDo

2 , Pa =1

2KA( H + Do )

2

3 ( + )

3 = 0

03 3 + = 0 (I)

From equ. (I) we can get the value of Do

Domust be increased by 20% to get theoretical value and by another 20% for

factor of safety.

This will give a safety factor of 1.5 to 2.0 approximately.

method

)

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method)

53

Blum solved the problem as a statically

problem.

The unknown is the penetration depth

"t" (i.e. x).

The principals for solving the problem

are the same as the simplified method.

0 =

P(L+x a =rx

3

6

3 =6

+ P P. a.

= .

3 =6

21 +

6

3.

3 = mII1 + nII

Where,

=6

2.P

0

=6

3 .

0

.

method

)

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method)

54

The values of mII, nII can be calculated.

Equation (2) can be solved by trial anderror or using the Nomogram given by

Blum for case NO. 2 to get value (Fig. 8). Calculate . Calculate t = u + 1.2 x.

Calculate xm, which is the location of zero

shear i.e. location of max. bending.

x 2P

Calculate the max. bending.

M P x a x

6

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Graphical Solution for Cantilever Sheet Pile Wall

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Graphical Solution for Cantilever Sheet Pile Wall

Steps :

1) Assume penetration depth.

2) Draw the net earth pressure on both sides.

3) Divide the net earth pressure and find the resultant foreach division.

4) Draw the force polygon.

5) Calculate the force (C) and bending moment.

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57

Charts for calculation ofpenetration depth andbending moment for

cantilever sheet pile insand soil

for some cases onlyI, II, III, IV

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Approximate Depth for Penetration of Sheet Pile in

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Approximate Depth for Penetration of Sheet Pile in

Sand

Soil Depth of penetration *

Dense 0.75h

Firm 1.0h

Loose 1.5h

Very loose 2.0h

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* h = high of piling above the dredge line.

Statical Calculations forCantilever Sheet Pile

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Cantilever Sheet PileWall in Cohesive Soil

Statical Calculations forCantilever Sheet Pile

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Cantilever Sheet PileWall in Cohesive Soil

(Cont.)

Cantilever S.P.W penetrating Clay

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Cantilever S.P.W penetrating Clay

2.2.4

Computer programs to calculate the

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2.2.4 Computer programs to calculate the

required items for design a sheet pile wall

64

.

..:

a. Using sub grad reaction theory (Fig.9).

b. Using finite element method with different soil models.

.Inertiadredge line

2.2.4

Computer programs to calculate the required items for design a sheet pile wall

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(Fig. 9) According to CUR 166

Determine the required depth of penetration

f th til h t il ll h i

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Ka= tan2(45-30/2) = 0.333,

KP = tan2(45+30/2) = 3.000

P 0.333 16 5.0 26.6kN/m

a .. 0.62m

P 26 .65 26.600.62

=66.5+8.2 = 74.7 kN Taking moments about O1and

dividing by P1.

for the cantilever sheet pile wall shown in

Fig. the soil is cohesionless soil, No ground

water.

Using conventional method

+

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67

Z..+... 2.08m p K Kb 16 2.667 b 42.7b

16 5 0.62 3.0 16 0.62 0.333 or p 266.5 42.7b From Eq.

m pb2Pp p

..

.+.

From Eq.

6

6 0 Or

74.7 2.08 42.7

6 266.585.46 42.7

149.4266.585.4

0 Or

448.2 2.08 42.742.7 149.4

266.585.4 0 Solving by trial and error, b = 4.4m

Alt ti th d f b

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68

Alternative method for b

Using Eq. b Cb Cb Cb C 0 Where

16 5 3.0 16 0.62 2.667162.667

.. 6.24

.

. 14.0 + . ..+.. 109.07 +

. ..+..

148.24 Therefore, 6.24 14.0

109.07 148.24 0 Solving by trial and error, b = 4.40 m

Therefore, d = b + a = 4.40 + 0.62 =

5.02

D = 1.30d=6.50m

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69

Using Simplified method

Taking moment about point A

+ 0

Substituting the values of P1 , P2

. + 0

3 3 0 Ka= 0.333 , Kp=3 , h=5.0 m 2.667d3-5d2-25d-41.67=0

Solving by trial and error d=4.70m

D=1,4d=6.58 m

B

C

P1

P2

h= 5m

d

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70

Using Blum method

h=5L=5.62

Xm = location forpoint of zero shear

u=0.62

Load (ton)

P1 0.0675

P2 0.2

P3 0.3325

P4 0.4675

P5 0.6

P6 0.7325

P7 0.8675

P8 1

P9 1.1325

P10 1.2675

P11 0.8

P12 0.033

Sum 7.5005

C

Distribution of net earth pressure

=7.5005 t

t

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Using Blum method

m1 n . P . .

1.6 3 0.33 4.26 . . 7.5 0.334 . . 26.55 0.21 From Blum Chart

=0.7

X = .L = 0.72 x 5.62 = 4.04 t = u +1.2 X = 0.62 +(1.2x4.04) 5.46m

Using F.S = 20%

Tact. = 5.46 x 1.2 = 6.55m

Calculation for point of zeroshear

x = .

. 1.87 M P x a = . a

0.9428.

=5.62 x 7.5 + 26.55 +

0.9428x0.484x20.539

=42.1-26.55+9.37 = 24.97 t.m

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arm Area moment

0 25 0 0025 0 000625

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To calculate deflection at point 0, M= 25m.t,Zsp calculated 1786 cm, Esteel=2100000

kg/cm2, Selected section Larssen AZ19, I

(cm4)=36980,

Deflection (cm)=8.589042455

0.25 0.0025 0.000625

0.75 0.025 0.01875

1.25 0.0975 0.121875

1.75 0.2525 0.441875

2.25 0.525 1.18125

2.75 0.9453 2.599575

3.25 1.5544 5.05183.75 2.375 8.90625

4.25 3.4475 14.65188

4.75 4.8025 22.81188

5.25 6.45 33.8625

5.75 8.2725 47.56688

6.25 10.0275 62. 67188

6.75 11.45 77.2875

7.25 12.2725 88. 97563

7. 75 12.2275 94. 76313

8.25 11.0475 91. 14188

8.75 8.4675 74.09063

9.25 4.2225 39.05813

9. 555 0.1888 1.803984

Sum 667.0079

By

Dr.

Amr

Radwan

Software Series

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74

By

Dr.

Amr

Radwan

Software Series

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Finite element Solution

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2.3

Design of Anchored sheet piles (Classical solution)

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g p

77

Statically there are two types of anchored

sheet piles:a. Anchored free sheet pile.

b. Anchored fixed sheet pile.

soil

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x 0 (I) T P

2 P

1 0 1T= Tensile force in anchorCalculation of depth (a)

Kh a Ka 0 a (2)12 MM = 0 (II)

1 + 1 2 + + 23 = 0 (3a)

Substituting the value of P2

14 + 1 2 + +2

3 = 0 (3b)

This equation can be written as under

b3 + 1.5b2g + a 3P1f(KPKa ) = 0 (4)

Where, f = a + h e Z1 , g = h eSolve equation (4) to find "b"

d= b+a , DPra.= 1.2 1.4 d

T = P1P2

Find the point of zero shears to calculate the max. bending.

2.3.2

Fixed earth support method for penetration in to sandy soil

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Calculation of location of point of inflexion

(i):

According to Blum (1931), there are a

relation between (i/h) and (Fig.2).

2.3.2


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80

With these assumptions, the problem is

statically determinate.

Method of statically calculation:

(Equivalent beam method)(Fig. 3)

Assume that the S.P. is a simply supported at

point "M" and fixed at the lower end K.

Then we can divide the beam in two parts:

a. Upper beam "BI".

b. Lower beam "IK".

2.3.2


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Steps for calculation

a. Design of top beam (B-I) (Fig. 4a):

(a)Upper Beam "BI"(1)Determine the pressure P1 at the dredge level.(2)Estimate the angle of shearing resistanceof the soil.(3)Determine the distance "i" of the point of inflexion from (Fig.2).(4)Determine the distance "a" of the point of zero pressure from the

equation,

a = P1

(KPKa ) (1)

(5)Determine the pressure Poat the point of inflexion from the relation,Po =

P1

a(a i) (2)

(6)Determine the reaction "RI" for the beam "IB" by taking momentsabout the point "M" of anchor forces acting on "IB" (Fig. 4a).

2.3.2


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Steps for calculation

b. Design of lower beam "I-K"

(a)Lower Beam "IK"(1)Determine the pressure "P2" from the relation

P2 = KP Ka(d a) (3)

Alternatively, P2 =Po

(ai) (d a)

(2)Determine the distance (d-a) by taking moment of the forces onthe beam "IK" about "K" (Fig. 4b) the reaction "RI" on the lower

beam is equal and opposite to that on the upper beam.

(3)Calculate "d" from Eq. (3) and hence find D = 1.2d.(10) Determine the tension "T" in anchor by considering the

equilibrium of beam "IB". Thus

T = P1- RI (4)

Where P1 = total force due to pressure on "IB".

support

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support

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Sheet pile wall is flexible. For anchored sheet pile in granular soils, the most significant factors are

(Rowe, 1952, Terzaghi, 1954).1- The relative density of soil.2- Relative flexibility of the sheet pile which is expressed in terms of

flexibility number.P =

H4

EI (English unit)

P = 1.1 106H 4

EI (metric unit)

H = total height of the sheet pile (m).

EI = modules of elasticity and moment of inertia for sheet pile 2 , (4/

support

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support

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For anchored sheet pile in cohesive soil, the most significant factors are(Rowe 1957, 1958):1-The stability number.

=

1 +

= 1.25

Ca = adhesion between soil and sheet pile.

2-Flexibility number.

P =H4

EI= 1.1 106 H4

EI

HH

3- Relative height of piling .

N.B

P = H

4

EI (English unit)

P = 1.1 106 H

4

EI

(Metric unit) (See charts Fig "1")

Charts

for the reduction

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of bending moment for

anchored free earth

support sheet pile wall

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2.4

Design of anchored sheet piles (Blum

method)

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2.4 Design of anchored sheet piles (Blum method)

86

Assumptions:

Rankine and Coulomb theories are valid.

Assuming fixation for sheet pile at the

location of C.

Treated the problem as statically

indeterminate problem.

The unknowns are the force in tie A and

the penetration depth "x".

The following are the steps for design.

2.4

Design of anchored sheet

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piles (Blum method)

87

Steps for design

Divide the forces as given in (Fig. 2).

Calculate the bending moment as a

function of the load.

Calculate the deflection at location of "A".

Steps of design

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Deflection due to force" A" (Fig. 2a)

EJf A. x

3From M O about point C

A x P x a P x a x

6 0

1 A 1 xP x a P x a x6

2 EJ f x

3 P x a P x ax6

3 EJ f Pa . x2 x

3

P6 2 x 3a x

Due to loads (Fig. 2c)

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4 EJf P. x a

2 a23 x a

P62 x 3a x aDue to passive pressure (Fig. 2d)

5 EJf x

6 x dx 1204x 5x

deflection at A = 0f 0

P62 x 2a x P62 x 2a x

x18 x

P

6 2 x

3a

x

P62 x

3a x

a

1204x

5x

6 . 6

36012 15 20 2

608 2520

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90

Put,

6 x . IWe get the following equation with the unknown

7 0,8 2,5 2,0

1 6 6.

Or in simple form

8 0,8 2,5 2,0 1 Where

6 .

6 .

9 6

+.

10

6

The mI,nI values are function of earth

pressure above the point of zero load and

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can be calculated.

The equation (8) can be solved

mathematically or using the monogram

to get . Calculate .

t = u + 1.2 x

Calculate the tension in tie A

+ 1

+

6

Calculate the max. moment at point of

zero shear

M

=Q.a

2.4.1

Design of anchors

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There are different

types of anchor (Fig

2.4/1):

Anchor plates and

beams (deadmen).

Brace piles.

Large existingstructure.

location of anchor plate (Fig.

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2.4/2)

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The method for determination of safelocation of anchor plate is given in (fig.

2.4/2).

2.4.3

Block stability for anchor free sheet pile

(

)

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(Cohesionless soil)

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The bloke stability must be calculated to

check the factor of safety for the tie force

(Fig. 2.4.3/1).

= The resultant of active earthpressure from point F' till H'(water pressure not to be

taken into consideration).

d = Calculated depth for

anchored free sheet pile.

= Factor of safety for the forcein tie 1.5As = Tension in tie from the

calculation of block stability.

Ac = Tension in tie from the

calculation of sheet pile.

N.B: If < 1.5, the length of tiemust be increased 45 /2

2.4.4

Typical steel work details

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