References: Coduto, D.P. (1994): Foundation design: principles and

practices

Day, R.W. (2010): Foundation engineering handbook

Hardiyatmo, H.C. (2011): Analisis dan PerancanganFondasi, Bagian II

Teng , Wayne C. (1992): Foundation Design

Tomlinson, M.J. (2001): Foundation design and construction

Deep Foundation

Topics (from SAP):Kapasitas dukung tiang terhadap gaya lateral dalam tanah kohesif

a. Ujung tiang bebas (tiang pendek dan tiang panjang)b. Ujung tiang terjepit (tiang pendek dan tiang panjang)

Defleksi tianga. Ujung tiang bebas (tiang pendek dan tiang panjang)b. Ujung tiang terjepit (tiang pendek dan tiang panjang)

Analisis stabilitas fondasi tiang

a. Beban tiangb. Kapasitas dukung tiangc. Jumlah tiangd. Susunan tiange. Kontrol

Turapa. Pengertianb. Tipe struktur turapc. Tipe turap dari segi bahan

Perancangan turap jenis kantilevera. Gaya-gaya yang bekerjab. Panjang turap yang dipancangc. Dimensi turap dan pemilihan profil turap

Perancangan turap dengan angkura. Letak tumpuan angkurb. Dimensi batang angkurc. Konstruksi angkur

Fondasi caissona. Pengertian dan jenis fondasi caissonb. Bentuk tampang fondasi sumuranc. Analisis fondasi sumuran

Design of Sheet Pile

• Determination of sheet pile stability

a. Calculate the depth of embedded sheet pile into the ground

b. Determinate the sheet pile dimension.

• Steel sheet pile use the table of section profile

• Concrete sheet pile use the table of section profile for corrugated sheet pile or determine the thickness and arrange the steel reinforcement

• Timber sheet pile determine the dimension

a. Cantilever-type sheet pile

1. For non-cohesive soil

Analyze the sheet pile width of 1 m drawing area

Determine d (depth of embedded part)

(SF = 1,50 - 2,00)

Sheet pile dimension is determined based on Mmaks

• Assuming:

The sheet pile is a fixed-solid structure, so that the elastic line appears as an inclined straight line rotating at Point Do

• Acting forces:

– Right side : ADo – active lateral earth pressure

DDo – Passive lateral earth pressure

– Left side : BDo – Passive lateral earth pressure

DoD – Active lateral earth pressure

• Forces Diagram

D D

Ea

EP1 -Ea

EP2 -Ea2

A

B

Do

A

B

Do

Do’Do’

do

d’d

(H+do)g.Ka

(H+do)g.KP d’g.KP dog.Ka d’g.Ka

dog.KP

H

• Sheet pile stability at every point:

• Use SF = 1,50 – 2,00 B-do can be defined. Then the length of embedded sheet pile (B-D) can be calculated

• In the analysis:

1. (SMP/SMA) > 1,50 - 2,00 at point Do , or

2. SF is used to divide EP

3. Length of embedded sheet pile is do = BDo

and the implemented (real) sheet pile embedment d = (1,20 - 1,40)do

0HF 0M

Stage of analysis:

Assuming Do same location as Do'

K force is acting on Do and remain unknown if :

SMP & SMA id calculated on Do

SMDo= 0 calculate do

and then decide d = 1,2do

Sheet pile dimension is determined from the actual Mmaks.

Mmaks at the point with distance of xfrom B, so (dMx/dx) = 0 or SD = 0

A

B

Do

DK

do d

x

Example:

A timber sheet pile with 2.00 m high, supporting the backfill with j = 30o, cohesion is neglected, g = 18 kN/m3 and s all timber = 10 MPa. Calculate the length and dimension of sheet pile to be used.

Solution:Calculation is being done on the sheet pile with the width of 1 m drawing area:

31

245tan2

j

aK

32

45tan2

j

pK

A

H = 2 m

do

B

Do

D

Do

D

B

A

H = 2 m

do

xX

K

Ea

EPd

and

With the distance to Do:

With the distance to Do:

aa KHE g2

121

oo ddHH 21

3

11822

1 2 oa dE

kN 232

oa dE

oa de 23

1

pop KdE g2

21

3182

1 2 op dE

kN 272

op dE

op de3

1

a. Determination of embedded sheet pile do

so

or

The actual embedded sheet pile:

Use d = 2,30 m

Total length of sheet pile = 4,30 m

0 DoM 0 ppaa eEeE

oooo dddd3

12723

12322

3392 oo dd

oo dd 08,22

m 85,1od

m 23,22,1 odd

b. Determination of sheet pile dimension

(thickness of timber sheet pile)

Mmaks occured at the location between B & Do

Analyzing point X with the distance of x m from B, so:

Distance from x:

Distance from x:

There are two methods to solve this problem

aax KxE g2

22

1

kN 232

xEax xeax 23

1

ppx KxE g2

21

kN 272

xE px xepx 23

1

1. SD = 0 (the sum of lateral forces = 0)

x = 1 , from point B to downward direction

2.

So :

x = 1 m, from point B to downward directionMmaks = Mx=1 = -18 kNm

pxax EE

pxpxaxaxx eEeEM

222723 xx

xxxxM x 23

12723

12322

3392

312 xxxM x

0

dx

Md x 02723 22 xx

Assuming: thickness = t m, width = 1 m

So:

Meanwhile

So: t = 0,104 m = 10,4 cm

Use: t = 11 or 12 cm

32

32 m 6

m 16

1 ttW

MPa 10 timberall s

6

kNm 18 timber

2atW

Mll s

a. Cantilever-type sheet pile

2. Cohesive soil

For cohesive soil, the internal friction angle is 0 or nearly 0.

Based on Japan Port & Harbour Association-Design Standard for Port and Harbour Structures coefficient of active lateral earth pressure for cohesive soil (Kac)= 0,50, meanwhile coefficient of passive lateral earth pressure for cohesive soil (KPc)= 2,00

Sheet pile supported by pile foundation

A combination of pile and horizontal sheet or horizontal and vertical sheet pile

The solution of this type of sheet pile may be divided into two parts :

a. The pile supports horizontal forces

b. Horizontal sheet pile construction or the combination of horizontal and vertical sheet pile

The pile supports horizontal forces

Pile, with a certain distance

30 cm

Horizontal sheet pile

H

⅓H

B

B

B

B

B

B

B

b

b

LayoutCross-section A-A

A A

Cohesive Soil Non-cohesive soil

1,5b

A

B

Do

D

9 cu.b

⅓H

do

d

1,5b

A

B

Do

D

⅓H

do

d

3b.do.g.KP

Example:

Sheet pile supported by piles (as shown in the picture) is installed on non-cohesive soil with j= 30o, c= 0, unit volume weight (g) = 17 kN/m3

Calculate:

a. The length of embedded sheet pile,

b. Dimension and thickness of the pile

sall timber = 10 MPa

Width of the pile = 10 cm

A

B

Do

D

⅓H

do

d

3b.do.g.KP

H=1,21,25

1,25

1,25

1,25

1,25

1,25

1,25

Solution:

A

B

Do

D

0,4 m

do

d

3b.do.g.KP

H=1,2 Ea

1,25

1,25

1,25

1,25

1,25

1,25

1,25

a. Determination of the pile length

Analyzing 1 m drawing area

(1 m)

Moment arm from Do = (0,40 + do) m

Moment arm from Do = ⅓do m

Equilibrium condition: SMDO = 0

Note: active lateral earth pressure should be calculated with the width of 1,25 m

3

12

3045tan2 aK 32

3045tan2 pK

kN 08,43

1172,12

12

1 22

1 aa KHE g

ooopop dddKdbE 3

1171,032

132

1 g

265,7 op dE

Trial: do = 1 -0,510

do = 1,1 -0,176

do = 1,12 -0,089 0

Use: do = 1,12 m

d = 1,2 do = 1,344 m or d = 1,40 m

Total length of the pile:

t = H + d = 1,20 + 1,40 = 2,60 m

opoa dEdE 3

14,025,1

ooo ddd 3

165,74,008,425,12

004,21,555,23

oo dd

b. Determination of pile dimension

Maximum moment occurred if:

We get x = 0,816 m

Mmax = -4,8165 kNm

pxpxaxaxx eEeEM

xExEM pax 314,025,1

0

dx

Md x

355,21,504,2 xxM x

x

0,4

X

⅓xEPX

Ea

A

B

D

Assuming: thickness = t m,width = b m

So:

If b = 0,10 m, we get t = 16,9997 cmUse t = 20 cm

32 m 6

1 tbW

MPa 10 timbera llsW

Ms

b

t

c. Determination of sheet pile thickness

EP

A

B

D

p = H.g.Ka kN/m’

1,25

1,25

1,25

Use the width of sheet pile = 1 unit length and thickness = tThe load acting of sheet pile p = HgKa

and use unit length of 1m

t = 0,0282 m or t = 2,82 cmUse t = 3 cm

kNm 328,1.8

1 2

max BpM

W

Ms

61 2tbW

B= 1,25 m

Mmax

p = H.g.Ka

b

t