TUGAS DINDING PENAHAN TANAH

Nama : Felix Cahyo Kuncoro Jakti

NPM : 0906511763

Program Studi : Teknik Sipil

Soal 15.9

Determine the stability of the concrete gravity wall shown in Fig. P15.9.

Jawab:

1. Calculate the active lateral earth force and its components.

Using Coulomb’s equation:

Besar gaya lateral aktif akibat backfill adalah

Besar gaya lateral aktif akibat beban terbagi merata adalah

Total gaya lateral aktif adalah

Besar gaya lateral pasif akibat backfill adalah

Besar gaya lateral pasif akibat gaya gesek di bawah dinding penahan beton

Total gaya lateral pasif adalah

Karena

2. Determine the weight of the wall and soil above the base.

3. Check translation.

4. Determine the location of the resultant vertical force, Rz, from the toe of the wall.

No Gaya Nilai (kN) Lengan momen

Momen

1 Wbeton segitiga 120 1,666666667 200

2 Wbeton persegi 48 2,75 132

3 Paz 11,88911 3 35,66733

4 Pax 44,37077 1,333333333 -59,161

5 Ppz 13,71172 0 0

6 Ppx 51,17282 0,2 10,23456

Total 318,7409

5. Check the Base Resistance

6. Check the stability

Soal 15.24

A cantilever retaining wall is required to support a cut near a residential area. A preliminary geometry of the wall is shown in Figure 2. A masonry wall 1,2 m high will sit on top of the wall, centered. The masonry wall load (including construction loading) is 9 kN/m and the uniform loading from the home site is 10 kPa.

The wall rotation is limited to 0,0005 Ho (Ho is the height of the wall). Check the adequacy of the wall. Determine a suitable wall geometry if the given geometry is unsatisfactory. Sketch a drainage scheme for the wall. Neglect wall friction. (Hint: the tolerable wall rotation is very small; it is less than the wall rotation to mobilize the active earth pressure). Jawab:

Cantilever Retaining Wall

Help

RESULTS

Overturning

(FS)T 4,31

Design is OK with respect to overturning

Sliding

(FS)SLIDING 2,05

Design is OK with respect to sliding

Bearing Capacity

(FS)B 1,04

FS is less than 3, consider increasing the base width, B

Eccentricity

Eccentricity e 0,44 m < 0,71 m = B/6

INPUT

INPUT

INPUT

Soil data

Wall data

External Load

Void Ratio, e 0,667

Height of wall above footing bottom

5,25 m

Uniform load 19 kPa

Porosity, n 0,400

Thickness of wall at top of wall 0,5 m

Specific Gravity, Gs 2,700

Thickness of wall at bottom of wall

0,75 m

Bearing capacity:

Water Content, w 10,0 %

Footing thickness 0,75 m

N 11,49

Saturation, S 40,5 %

Footing base width, B 4,25 m

max 188,64 kPa

Bulk unit weight, 18,0 KN/m3

Front of footing toe to wall distance

0 m

Effective width

3,37 m

' 28 degrees

Depth of soil in front of wall (to bottom of footing)

1,25 m

i 0,560808

' 0,49 radians

Slope of backfill, 0

Height H0 5,3 m

Concrete-soil interaction factor (use in sliding)

0,85 * '

Depth of shear key 0 m

Active Earth Pressure

Resultant Forces (includes Wsoil, Wwall, Wfooting, PA, and PP)

KA 0,361 (Rankine)

Rx 86,6 KN/m

PA 89,6 KN/m

Ry 494,0 KN/m

PA,V 0,0 KN/m

R 501,5 KN/m

PA,H 89,6 KN/m

(CCW from horizontal) 80,05 degrees

Fx 36,0 KN/m

r 1,68 m

dA 2,00 m

Passive Earth Pressure

KP,R 2,770

PP,R 39,0 KN/m

dP 0,4 m

Weights

Weight of soil (block 1) 0,0 KN/m

Weight of soil (block 2) 283,5 KN/m

Weight of surcharge 66,5 KN/m

Weight of entire soil block and surcharge 350,0 KN/m

toe to centroid distance 2,50 m

s 1,75 m

Weight of Concrete 144 KN/m

concrete 24 KN/m

3

c 1,33 m

Wwall 54 KN/m

c(Wwall) 0,50 m

Wbatter section 13,5 KN/m

c(Wbatter section) 0,17 m

Wfooting 76,5 KN/m

c(Wfooting) 2,13 m

PA

dpPP

dkey

de

pth

of

ba

ckfill

in

fro

nt

of

wa

ll

width of bottomof wall

Front of footing toeto wall distance

He

igh

t o

f w

all a

bo

ve

fo

otin

g b

otto

m

c

WsoilWconcrete

s

Rx and Ry are x and y components ofthe resultant force, R. R includes theactive and passive forces, and the weightsof the concrete and soil. The dimension r is the horizontal distance from the toe of thefooting to the line of action of Ry.

Soil Properties:

', c=0, moist

sloping backfill

Footing base width, B

Active earth pressurediagram (schematic)

thickness of

footing

thickness of top of wall

vertical wall

Passive earth pressurediagram (schematic)