TEST PAPER OF GEOTECH1.docx

7/22/2019 TEST PAPER OF GEOTECH1.docx

1/21

Sub: Geotechnical Engineering Topic : Soil Mechanics

JH ACADEMY Page 1

TEST PAPER OF GEOTECH

___________________________________________________________________________

1. In a liquid limit test, the moisture contentat 10 blows was 70% and that at 100

blows was 20%. The liquid limit of the

soil is

a) 35% b) 50% c) 65% d) 45%2. The active earth pressure of a soil is

proportional to

a) b) c) d)

3. The quantity of seepage of water throughsoil is proportional to

a) Coefficient of permeability of soilb) Total head loss through the soilc) Neither a nor bd) Both a and b

4. The maximum value of effective stress inthe past divided by the present value is

defined as over consolidation ratio (OCR).

The OCR of an over consolidated clay is

a) Less than 1b) 1c) More than 1d) None

5. If number of flow channels are 10,number of drops are 6, the total hydraulic

head difference is 4m, the length of dam is

50m and the coefficient of permeability is

2 , the total loss of water perday in isa) 576 b) 5760 c) 57600 d) 576000

6.

A flow line makes angles and withthe normal to the interface of the soils

having permeabilities 3 and1 before and after deflection.According to the law of deflection of flow

lines at the interface of the dissimilar soils,

the isa)

b)

c)

d)

7. A compacted soil sample using 10%moisture content has a weight of 200g and

mass unit weight of 2.0g/cc. if the specific

gravity of soil particles and water are 2.7

and 1.0, the degree of saturation of the soil

is

a) 11.1% b) 55.6% c) 69.6% d) 80%8. Sieve analysis was carried out on a soil

sample of 400gms. Out of 400gms, of soil

160gm retained on 4.75mm sieve, 120gm

retained on 2mm sieve and 80gm retained

on 600 sieve. The value of will be

a) 7.4, 1.7b) 1.7, 7.4c) 7.92, 1.4d) 1.4, 7.92

9. Degree of saturation of a natural soildeposit having content 15% specific

gravity 2.50 and void ratio 0.5 isa) 50% b) 60% c) 75% d) 80%

10. The liquidity index is defined as a ratioexpressed as percentage of

a) Plastic limit minus natural watercontent, to its plasticity index

b) Natural water content minus itsplastic limit to its plasticity index

c) Natural water content plus in elasticlimit, to its plasticity index

d) Liquid limit minus natural watercontent to the plasticity index.


2/21


JH ACADEMY Page 2

11. A coarse grained soil has a void ratio 0.75and specific gravity is 2.75. the critical

gradient at which quick sand condition

occurs is

a) 0.25 b) 0.50 c) 0.75 d) 1.0012. The weight of a Pycnometer containing

400g sand and water full to the top is

2150gr. The weight of Pycnometer full of

clean water is 1950g. if specific gravity of

the soil is 2.5, the water content is

a) 5% b) 10% c) 15% d) 20%13. A permeameter of 82.5mm diameter

contains a column of the fine sand 460mm

long. When water flows through it under a

constant head at a rate of 191

, the

loss of head between two points 250mm

apart is 380mm. calculate the coefficient

of permeability? If the falling head test is

made on the same sample using a stand

pipe of diameter 30mm, in what time the

water level in stand pipe fall from

1560mm to 1066mm above out flow

level?

14. A 10m thick layer of clay is under lainedby a 4m thick layer of sand. The water

table is at a depth of 4m from the ground

level. The void ratio of clay is 0.65 and

specific gravity is 2.67 water content

above the saturated soil is 17% and void

ratio of the sand is 0.567 and G= 2.65.

Determine total and effective stress.

15. A borrow area soil has a natural watercontent of 10% and the bulk density of

1.8Mg/. The soil is used for anembankment to be compacted at 18%

moisture content to a dry density of1.85Mg/. Determine the amount ofwater to be added to 1 of borrow soil.How many of excavated soil requiredfor embankment.

16. A new canal is excavated to a depth of 5mbelow ground level through a soil having

the following characteristics. C=14KN/ the slopeof banks is . Calculate the factor ofsafety with respect to cohesion when thecanal runs full. If it is suddenly and

completely emptied, what will be the

factor of safety?

17. A saturated specimen of cohesion lesssand tested in tri axial compression and

the ample failed at a deviator stress of482KN/ when the cell pressure was100KN/ under drained conditions. Findthe effective angle of shearing resistance

of sand. What would be the deviator stress

and the major principal stress at failure for

another identical specimen of sand it is

tested under cell pressure of 200KN/.18. A concentrated point load of 200KN acts

at the ground surface. Find the intensity of

vertical pressure at a depth of 10m below

the ground surface and situated on the axis

of the loading. What will be the vertical

pressure at a point at a depth of 5m and at

a radial distance of 2m from the axis of

loading?

19. Compute the total, effective and porewater pressure at a depth of 20m below

the bottom of a lake 6m deep. The bottom

of lake consists of soft clay with a

thickness of more than 20m. The average

water content of the clay is 35% and

specific gravity of the soil may be

assumed as 2.65.

20. The subsoil strata at a site consist of finesand 1.8m thick overlaying a stratum of

clay 1.6m thick. Under the clay stratum

lies a deposit of coarse extending to a

considerable depth. The water table is

1.5m below the ground surface. Assuming

the top fine sand to be saturated by

capillary water, calculate the effectivepressure at ground surface an at depth of

1.8m, 3.4m and 5m below the ground

surface. Assume for find sand a=2.65,

e=0.8 and for coarse sand a=2.66, e=0.5.

what will be the change in effective

pressure at depth 3.4m if no capillary

water is assumed to be present in the fine

sand and its bulk unit weight is assumed to

be 16.68KN/ The unit weight of clayis 19.32KN/.


3/21


JH ACADEMY Page 3

21. The load from a continuous footing ofwidth 2m, which may be considered to be

strip load of considerable length, is

200KN/. Determine the maximumprincipal stress at 1.5m depth below the

footing, if the point lies (i) directly belowthe centre of the footing (ii) directly below

the edge of the footing, (iii) 0.8m away

from the edge of the footing.

22. In a laboratory consolidometer test on a20mm thick sample of saturated clay taken

from a site, 50% consolidation point was

reached in 10min. Estimate the time

required for the clay layer of 5m thickness

at the site for 50% compression if there

drainage only towards the top. What is the

time required for the clay layer to reach

50% consolidation if the layer has double

drainage instead of single drainage.

23. A layer of soft clay is 6m thick and liesunder a newly constructed building. The

weight of sand overlying a clay layer

produces a pressure of 2.6Kg/ and thenew construction increases the pressure by

1.0kg/. If the compression index is0.5. Compute settlement. Water content is

40% and specific gravity of grains is 2.65.

24. A vane, 10cm long and 8cm in diameter,was pressed into soft clay at the bottom of

a bore hole. Torque was applied and

gradually increased to 45N-m when

failure took place. Subsequently, the vane

rotated rapidly so as to completely

remould the soil. The remoulded soil was

sheared at a torque 18N-m. Calculate the

cohesion of clay in the natural and

remoulded states and also the value of thesensitivity.

25. A cut 9m deep is to be made in clay with aunit weight of 18KN/ and cohesion of27KN/. A hard stratum exists at adepth of 18m below the ground surface.

Determine from Taylors stability number

of factor of safety is 1.5.

26. In a consolidation test the followingresults were obtained. When the load waschanged from 50KN/ to 100KN/,

the void ratio changed from 0.7 to 0.65.

Determine the coefficient of volume

decrease and the compression index.

27. A cylindrical specimen of a saturated soilfails under an axial stress of 150KN/ inan unconfined compression test. Thefailure plane makes an angle of withthe horizontal. Calculate the cohesion and

angle of internal friction of soil.

28. Size of an isolated footing is to be limitedto 1.5m square. Calculate the depth at

which the footing should be placed to take

a load of 200KN with a factor of safety 3.

The soil is having angle of internal

friction=

. The weight of soil is

21KN/. Bearing capacity factors for 29. A footing rests at a depth of 1m has a size

of 3m and it causes a pressureincrement of 200KN/ at its base. Thesoil profile at the site consists of sand for

the top 3m, which is underlained by a clay

layer of 3m. Water table is at a depth of

2.5m from the ground surface. The units

weight of sand layer above and below

water table are 16KN/ respectively. The unit weight of clay is15KN/ the initial void ratio is 0.8 andcompression index is 0.3. Determine the

consolidation settlement at the middle of

the clay layer. Assume 2:1 pressure

distribution and consider the variation of

pressure across the depth of the clay layer.

30. A group of 16 Piles of 50cm diameter isarranged with a centre to centre spacing of

1.0m. The piles are 9m long and are

embedded in soft clay with cohesion

30KN/m. bearing resistance may be

neglected for the piles. Adhesion factor is

0.6. Determine the ultimate load capacity

of the pile group.

31. A pile group consists of a piles 30cmdiameter and 10m length driven in clay.

Unconfined compressive strength of soil is

200KN/. And insitu density of soil is200KN/ determine the safe load for thepile group.


4/21


JH ACADEMY Page 4

32. A building 10m in plan is built ona raft foundation resting on the surface.

The soil profile consists of 4m dense sand

over 3m thick silty clay resting on rock.

The water table is at 2m below groundlevel. Consolidation test conducted on

UDS of clay layer gave the following

results. Initial and final void ratios and

corresponding stresses are ,=1.0, KN/.If the weight of the building is 1000KN.

What is the settlement?

33. Calculate the ultimate bearing capacity perunit area of (i) strip footing 2.5m wide (ii)

square footing 4.75

(iii) circular

footing 5.2m dia. The footing is supported

on a soil for which the following data is

available. KN/.c=17KN/,depth=1.75m,

34. An embankment of 10m height isconstructed in a soil having c=

0.02N/ KN/.Find the factor of safety with respect to

cohesion and also the critical height ofembankment. Assume stability

number=0.05

35. Find the factor of safety against slidingalong the interface for infinite slope with

slope of. =16KN/, c=10KN/, Also find the height z that willgive F.S of 2 against sliding along the

interface.

36. A pile is driven with a single acting steamhammer of weight 15KN with a free fall

of 900mm. The final set, the average of

the last three blows is 27.5mm. Find the

safe load using the engineering news

formula.

37. A retaining wall is 4m high. Its back isvertical and it has got sandy backfill up to

its top. The top of the fill is horizontal

carries a uniform surcharge of 85KN/.Determine the active earth pressure on the

wall per meter length of wall. Water table

is 1m below the top of the fill. Dry density

of soil =18.5KN/. Moisture content ofsoil above water table=12%. Angle of

internal friction of soil =specificgravity of soil particles=2.65, porosity of

backfill=. The wall friction may beneglected.

38. Compute the safe bearing capacity ofsquare footing 1.5m1.5m located at adepth of 1m below the ground level in a

soil of average density 20KN/. , .Assume a factor of safety of 2.5 and that

the water table is very deep. Also compute

the reduction in safe bearing capacity of

the footing if the water table rises to the

ground level.

39. Plate load test was performed on densesand. Size of plate is 0.2. find thesettlement of a footing of size 3m under the pressure of 20KN/ if the

plate settles by 5mm under this pressure.

40. A smooth retaining wall of 9m highretains for a top 4.5m soil with cohesion 0

and internal friction. KN/.For the bottom 4.5m, the soil has cohesion

of 0 and internal friction, KN/. Top surface of soil ishorizontal. Find resultant pressure and its

point of application.

41. The field N value in a deposit of fullysubmerged find sand was 40 at a depth of

6m. The average saturated unit weight of

soil is 19KN/.calculate the corrected Nvalue.

42. A reinforced concrete pile weighing 30KN(inclusive of helmet and dolly) is driven

by a drop hammer weighing 40KN and

having an effective fall of 0.8m. The

average set per blow is 1.4cm. The total

temporary elastic compression is 1.8cm.

Assuming the co-efficient of restitution as

0.25 and factor of safety of 2, determine

the ultimate bearing capacity and the

allowable load for the pile.

43. A 450mm wide, square in section concretepile, 15m long is driven in a deep deposit


5/21


JH ACADEMY Page 5

of uniform clay laboratory unconfined

compression tests on undistributed

samples indicates an average unconfined

compressive strength of 75KN/.Calculate the ultimate load capacity of the

pile. Take adhesion factor as 0.8 and as9.44. A group of 44 piles is driven to bear in a

dense sand layer 2.5m thick. Pile spacing

is 1.0m c/c, diameter is 0.4m. the total

load on top is 3000KN. A compressible

layer of clay, 2m thick exists below dense

sand. Clay is underlained by rock. Find

the settlement of pile group if co-efficient

of volume compressibility of clay layer is

1.5

/KN.

45. A smooth vertical wall of 4.5m high,retains a soil with c= 25KN/, The horizontal backfill surfacecarries a uniform surcharge load

50KN/. The retaining wall is tend tomove towards the soil. What is the

magnitude and point of application of total

pressure?

46. Determine the safe load carrying of pilegroup consists of 9 friction pile of 30cm

diameter and 12m lengths driven in soft

clay. F.S=3, 0.6.

47. A square pile group of 16 piles penetratesthrough a filled up soil of 3m depth. The

pile diameter of 250mm and file spacing is

0.75m. The unit cohesion of the material

is 18KN/. And the unit weight of soil is15KN/

compute the negative skin

friction on the group.

48. The load carrying capacity (against shearfailure) of a surface square footing

founded on sandy soil is 800 KN. If the

size of the square footing is reduced by

one half, what will be its load carrying

capacity against shear failure?

49. Determine the depth at which a circularfooting of 3.3m diameter be found to be

provided to carry a safe load of 1500KNwith a factor of safety of 2.40. the

foundation soil has c=9KN/ r=18KN/.

50. A footing 3m2m in plan transmits apressure of 160KN/ on a cohesive soilhaving E= 9 KN/ and =0.46.Determine the immediate settlement of thecentre.

51. A saturated sand has a dry unit weight of18KN/ and a specific gravity of 2.65. If=10KN/, the water content of thesoil is .

52. The void ratio of sample is 1 thecorresponding porosity of the sample is

53.

The total unit of soil is 18.8KN/, thespecific gravity (G) of the solid particlesof the soil is 2.67 and water content of the

soil is 12% calculate dry unit weight, voidratio and degree of saturation.

54. The unit weight of a soil at zero air voidsdepends on

a) Specific gravityb) Water contentc) Unit wt. of waterd) All

55. Which one of the following relations isnot correct?

a) b) c) d)

56. If the porosity of soil sample is 20%, thevoid ratio is

a) 0.20 b) 0.80 c) 1.00 d) 0.2557. Principle involved in relationship between

submerged unit weight and saturated unit

weight of soil is based on

a) Equilibrium of floating bodiesb) Archemedes principlec) Stokess lawd) Darcys law

58. A soil sample has a void ratio 0.5 andporosity will be close to

a) 50% b) 66% c) 100% d) 33%


6/21


JH ACADEMY Page 6

59. A barrow pit soil has a dry density of17KN/. How many cubic meters of thissoil will be required to construct an

embankment of 100 volume with a drydensity of 16KN/a) 94 b) 106c) 100 d) 90

60. The void ratio and specific gravity of asoil are 0.65 & 2.72 respectively. The

degree of saturation (%) corresponding to

water content of 20% isa) 65.3 b) 20.9 c) 83.7 d) 54.4

61. A saturated soil mass has a total density22KN/ and water of 10%. The bulkdensity and dry density of the soil area) 12KN/and 20KN/

b) 22 &20KN/c) 19.8 &19.8KN/d) 23.2 & 19.8KN/

62. The water content of saturated soil and thespecific gravity of soil solids were found

to be 30% and 2.7 respectively. Assuming

the unit of water to be 10KN/, thesaturated unit weight (KN/) and thevoid ratio of the soil are

a) 19.4, 0.81b) 18.5, 0.30c) 19.4, 0.45d) 18.5, 0.45

63. The saturated unit weight of the sand(KN/) is to be find for water content=20%, G= 2.7 and =10KN/a) 15 b) 18 c) 21 d) 24

64. A saturated undistributed sample from aclay stratum has moisture content of

22.22% and specific weight is 2.7.

assuming

=10KN/

, the void ratio

and saturated unit weight of clayrespectively are

a) 0.6 and 16.875KN/b) 0.3 and 20.625KN/c) 0.6 and 20.625KN/d) 0.3 and 16.975KN/

65. In a compaction test, G, W, S, and erepresent the specific gravity, water

content, degree of saturation and void

ratio of the soil sample respectively. If represents unit weight of water and represents the dry unit weight of the soil,

the equation for zero-air voids line is

a)

b) c) = d)

66. In this natural condition, a soil sample hasa mass of 1-980kg and a volume of

0.001. After being completely dried inan oven, the mass of sample is 1.8kg.

Specific gravity G is 2.7. Unit weight of

water is 10KN/. The degree ofsaturation of the soil is

a) 0.65 b) 0.70 c) 0.54 d) 0.6167. The maximum possible value of group

index for a soil is .

68. The description sandy silty clay signifiesthat

a) The soil contains unequal proportionsof the three constituents in the order

sand > silt > clay

b) The soil contains equal proportions ofsand, silt and clay

c) The soil contains unequal proportionsof three constituents such that

clay>silt>sandd) There is no information regarding the

relative proportions of the three

69. The Atterberg limits of clay are 38%, 27%and 24.5%. Its natural water content is30%. The clay is in state.

70. A soil having particles of nearly the samesize is known as

a) Well gradedb) Uniformly gradedc) Poorly gradedd) Gap graded

71. The consistency of saturated cohesive soilis affected by

a) Water contentb)

Particle size distribution

c) Density indexd) Co-efficient of permeability

72. The equation of A-line in the plasticitychary is .

73. The particle size distribution curves areextremely useful for the classification of

a) Fine grained soilsb) Coarse grained soilsc) Both fine and coarse grained soilsd) Silts and clays


7/21


JH ACADEMY Page 7

74. Consistency index for a clay soil isa)

b) c) LL-PLd) 0.5w

75. Some of the structural strength of a clayeymaterial is lost by remolding is slowly

recovered with time. This property of soils

to undergo an isothermal gel-to-sol-to-geltransformation upon agitation and sub-

sequent rest is termed

a) Isotropyb) Anisotropyc) Thixotropyd) Allotropy

76. The values of liquid limit and plasticityindex for soils having common geologicalorigin in a restricted locality usually

define

a) A zone above A-lineb) A straight line parallel to A-linec) A straight line perpendicular to A-lined) Points may be anywhere in the

plasticity chart

77. The toughness index of a clayey soils isgiven by

a) Plasticity index/flow indexb) Liquid limit/plastic limitc) Liquidity index/plastic limitd) Plastic limit/ liquidity index

78. Soil has been compacted in anembankment at bulk density of 2.15Mg/

and a water content of 12%. The valueof specific gravity of soil solids is 2.65.

The water table is well below the

foundation level. Estimate the dry density,

void ratio, degree of saturation and air

content of compacted soil.

79. The un drained cohesion of a remouldedclay soil is 10KN/. If the sensivity ofthe clay is 20, the correspondingremoulded compressive strength is

a) 5KN/ b) 10KN/c) 20KN/ d) 200KN/

80. A soil mass contains 40% gravel,50%sand & 10% silt. The soil can be

classified as

a)

Silty sandy gravel having co-efficientof uniformity less than 60

b) Silty gravelly sand having co-efficientof uniformity equal to 10

c) Gravelly silty sand having co-efficient of uniformity greater than 60

d) Gravelly silty sand and its coefficientof uniformity cannot be determined.

81. In a standard proctor test, 1.8kg of moistsoil was filling the mould

(volume=944Cc) after compaction. A soil

sample weighing 23g was taken from

mould and over dried for 24 hours at a

temperature of C weight of the drysample was found to be 20g. Specific

gravity of soil solids is a=2.7. the

theoretical maximum value of the dry unit

weight of the soil at that water content is

equal to

a) 4.67KN/ b) 11.5KN/c) 16.26KN/ d) 18.85KN/

82. Laboratory sieve analysis was carried outon a soil sample using complete set of

standard IS sieves. Out of 500gr. Of soil

used in the test, 200g was retained on IS-

600

size, 250g was retained on IS-500

sieve and remaining 50g was retained on

IS-425 sievea) The Coefficient of uniformity of soil

is

a. 0.9 b. 1.0 c. 1.1 d. 1.2b) The classification of soil is

a. SP b. SW c. CI d. GW83. Sieve analysis on a dry soil sample of

mass 1000g showed that 980g and 270g of

soil pass through 4.75mm and 0.075mm

sieve, respectively. The liquid limit and

plastic limit of the soil fraction pass

through 425 sieves are 40% and 18%respectively. The soil may be classified as

a) SC b) MI c) CI d) SM84. Group symbols to silty sand and clayey

sand are respectively

a) SS and CSb) SM and CSc) SM and SCd) MS and CS


8/21


JH ACADEMY Page 8

85. The liquid limit (LL), plastic limit (PL)and shrinkage limit (SL) of a cohesive soil

satisfy the relation

a) LL>PL>SLb) LL>PL>SLc)

LL>PL


9/21


JH ACADEMY Page 9

96. A 5m thick clay layer lies between twolayers of sand each 4m thick, the top of

the upper layer of sand being at ground

level. The water table is 2m below the

ground level but the lower layer of sand is

under artesian pressure the piezometricsurface being 4m above ground level.Of clay is 20KN/ & of sand is19KN/. Above water table of sand is16.5KN/. Calculate the effectivestresses at top and bottom of the clay

layer.

97. Data from a sieve analysis conducted on agiven sample of soil showed that 67% of

the particles passed through 75. The and

of the finer fraction was found to

be 45% and 33% respectively. The group

symbol is

a) SC b) MI c) CH d) MH98. For the soil strata shown in fig. the water

table is lowered by drainage by 2m and if

the top 2m thick silty sand stratum

remains saturated by capillary action even

after lowering of water table. The increase

in effective vertical pressure in KPa at

mid height of clay layer will be

99. A 10m thick clay layer is underlain by asand layer of 20m depth. The water table

is 5m below the surface of clay layer. The

soil above the water table is capillary

saturated. =19KN/. If now thewater table rises to the surface, theeffective stress at a point P on the

interface will

(a) Increase by 5(b) Remain unchanged(c) Decrease by 5(d) Decrease by 10

100.Assuming that a river bed level does notchange and the depth of water in river was

10m, 15m and 8m during the months of

February, July and December.Respectively of a particular year.

=20KN/. 10KN/. Theeffective stress at a depth of 10m below

river bed during these months would be

Feb July dec

a) 300 350 320b) 100 100 100c) 200 250 180d) 300 350 280

101.The coefficient of permeability of a soilis 5 cm/sec for a certain porefluid. If the viscosity of the pore fluid is

reduced to half, the co-efficient of

permeability will be

a) 5 cm/secb) 10 cm/secc) 2.5 cm/secd) 1.25 cm/sec

102.The piezometric head at point C, in theexperimental set up shown in fig. when


10/21


JH ACADEMY Page 10

the flow takes under constant head

through the soils A and B is

a) 0 cmb) 40 cmc) 80 cmd)

120 cm

103.According to Darcys law for flowthrough porous media, the velocity is

proportional to

a) Effective stressb) Hydraulic gradientc) Cohesiond) Stability number

104.In a falling head permeameter test on asilty clay sample, the following results

were obtained: sample length 120mm;

sample diameter;80mm; initial head 1200

mm, final head 400mm, time for fall in

head 6 minutes, stand pipe diameter

4mm, find the coefficient of permeabilityof the soil in mm/sec

105.The two tubes shown in fig. may beconsidered to be permeameter.

Dimensions of the sample in Fig (i) &

(ii) are alike, and the elevations of head

water and tail water are the same for both

the figures. A, B. . . etc. indicate points

and AB,AE. . .etc. indicate heads loss

through these samples are

a)

(i) BD (ii) FBb) (i) AC (ii) AE

c) (i) AD (ii) AFd) (i) AB (ii) AB

106.Estimate the flow quantity (in liters/ sec)through the soil the pipe shown below.

The pressure heads at two locations

shown in figure. The internal diameter of

pipe is 1m and coefficient of

permeability is 1 m/sec

107.In filling head permeability test the initialhead of 1.0m dropped to 0.35m in 3

hours, the diameter of stand pipe 5mm.

the soil specimen was 200mm long and

100mm diameter. The coefficient of

permeability of the soil is

a) 4.86 cm/secb) 4.86

cm/sec

c) 4.86 cm/sec


11/21


JH ACADEMY Page 11

d) 4.86 cm/sec108.In a constant head permeameter with

cross section area of , when theflow was taking place under a hydraulic

gradient of 0.5, the amount of watercollected in 60 section is 600 cc. the

permeability of the soil is

a) 0.002 cm/sb) 0.02 cm/sc) 0.2 cm/sd) 2.0 cm/s

109.The soil profile below a lake with waterlevel at elevation =0 m and lake bottom

at elevation =-10 m is shown in fig.

where k is permeability co-efficient. A

piezometer installed in sand layer shows

a reading of +10 m elevation. Assume

that the piezometric head is uniform in

the sand layer. The quantity of water (in

) flowing into the lake from thesand layer through the silt layer per unit

area of lake bed is

a) 1.5 b) 2.0 c) 1.0 d) 0.5

110.Terzaghis one dimensionalconsolidation theory assumes that

a) relationship is linearb) is linearc) is lineard) is linear

111.A sampling tube has inner diameter of72mm and an outer of 75mm. The area

ratio is .

112.A saturated clay layer of 5m thicknesstakes 1.5 year for 50% primary

consolidation when drained on both

sides. Its coefficient of volume change

/KN. Determine co-efficient of compressibility (in )and the coefficient of permeability (in

m/yr.) Assume KN/113.The coefficient of consolidation is used

for

a) Establishing the duration of primaryconsolidation

b) Establishing the amount of settlementfor a load increment

c) Determining the depth to which thesoil is stressed when loads are applied

on the surface of a soil deposit

d) Determining the pre-consolidationpressure for soil deposits known to beover-consolidated.

114.A standard Oedometer test in thelaboratory indicated that 0.02 m thick

clay specimen took 0.5 day to undergo

90% primary consolidation. How many

days will a 2m thick layer of identical

clay sandwiched between sand layers and

subjected to an identical stress increment

take to undergo the same?

115.The number of flow channels and headdrops is 4 and 12 respectively. If the

difference in the U/s and d/s water levels

is 3 m, what is the discharge per m width

of a sheet pile wall, if K=0.1 m/s?

116.A footing 1.5 m square is located 1.5 mbelow the surface of a uniform soil

deposit of density 20 KN/

. If the total thickness of

the deposit, which is underlain by rock

strata, is 3.5 m, compute the primary


12/21


JH ACADEMY Page 12

consolidation settlement of footing when

it carries a load of 225 KN. 2:1

distribution is to be used. Consider 2

layers.

117.A homogeneous anisotropic earth damwhich is 20m high constructed on an

impermeable foundation. m/s and m/s. thewater level on reservoir side is at 18m

from the base of the dam. Downstream

side is dry. It is seen that there are 4 flow

channels and 18 equi potential drop in a

square flow net drawn in the transformed

dam section. Estimate the quantity of

seepage per unit length.

118.In the laboratory test on a clay sample ofthickness 25mm drained at top only, 50%

consolidation occurred in 11 minutes.

Find the time required for the

corresponding clay layer in the field 3m

thick and drained at top and bottom, to

undergo 70% consolidation. Assume

119.A 20 mm diameter well fully penetrates a

confined aquifer of 30m depth. For a

pumpage of 35 lit/sec the steady draw

downs at 100 m and 300m distances from

the well are observed as 3.2m and 2.5m

respectively. Estimate the K in m/day

and transmissibility of the aquifer in /day. Estimate also the draw down at the

well.

(Transmissibility= permeabilitydepth ofaqifer)

120.A clay layer 8m thick is subjected to apressure of 70 KN/. If the layer has adouble drainage and undergoes 50%consolidation ( ) in one year.Determine the coefficient of

consolidation? If the K is 0.04 m/year

find settlement in one year. Use KN/

121.A soil mass has co-efficient of horizontaland vertical permeability as cm/s and 4 cm/s respectively. Thetransformed permeability of anequivalent isotropic soil mass is

a) cm/sb) cm/sc) cm/sd) cm/s

122.In a compaction test, as the compactioneffort is increased, the optimum moisture

content

a) Decreasesb) Remain samec) Increasesd) Increases first there after decreases

123.The slope of the e-log P curve for a soilmass gives

a) Co-efficient of permeabilityb)

Coefficient of consolidation c) Compression index

d) Coefficient of volume compressibility

124.A settlement analysis carried outproposed structure indicates that 9 cm of

settlement will occur in 5 years and the

final settlement will occur in 50 year and

final settlement will be 45 cm based on

double drainage exists. Estimate the

settlement at the end of 5 years for the

changed condition.

125.The time for a clay layer to achieve 90%consolidation is 15 years. The time

required to achieve 90% consolidation, if

the layer were twice as thick, 3 times

more permeable and 4 times more

compressible would be

a) 70 yearsb) 75 yearsc) 80 yearsd) 85 years

126.Consolidation in soilsa) Is a function of effective stress

b) Does not depend on the present stressc) Is a function of the pore water

pressure

d) Is a function of the total stress127.For an isotropic soil, permeabilities in x

and y directions are respectively in a two dimensional flow.


13/21


JH ACADEMY Page 13

The effective permeability for thesoil is given by

a) b) c) ( )

d) () 128.A building is constructed on the ground

surface beneath which there is a 2m thick

saturated clay layer sand witched

between two highly pervious layers. The

building starts setting with time if

=2.5 cm/s. in how many dayswill the building reach half of its final

settlement?

129.In an Oedometer test, a specimen ofsaturated clay 19 mm reaches 50%

consolidation in 20 minutes. How long it

would take a layer of this clay 5m thick

to reach the same degree of consolidation

under the same stress and drainage

conditions? How long would it take for

the clay layer to reach 30%

consolidation?

130.A well of 300mm diameter is located in aconfined aquifer of 40m thick. The

aquifer has a hydraulic conductivity of 25

m/day. And the radius of influence is 300

m. determine the discharge if the

diameter in / hr. from the well if thedraw down is 3m. also determine the %

increase in discharge if the diameter is

made to 450mm, with other conditions

remains same.

131.The time for a clay layer to achieve 85%consolidation is 10 years. If the layer was

half as thick, 10 times more permeable

and 4 times more compressible. The time

that would be required to achieve the

same degree of consolidation is

a) 1 yearb) 5 yearsc) 12 yearsd) 16 years

132.At a reclamation site for which the soilstrata is shown in Fig. a 3m thick layer of

a full material is to be laid instaneous on

the top surface. If the coefficient of

volume compressibility for clay is2.2 /KN, the consolidationsettlement of the clay layer due to

placing of fill material will be

a) 69.5mmb) 139mmc) 228mmd) 278mm

133.A 6m thick clay layer under goes 90%consolidation four times faster under two

way drainage as compared to one

drainage in an identical clay of 15m

thick, two way drainage will be faster as

compared to one way drainage by

a) 8 timesb) 4 timesc) 2.5 timesd) 2 times

134.A 6m thick clay layer under goes 90%consolidation four times faster under twoway drainage as compared to one

drainage in an identical clay of 15m

thick, two way drainage will be faster as

compared to one way drainage by

e) 8 timesf) 4 timesg) 2.5 timesh) 2 times

135.The average effective over burdenpressure on 10 m thick homogeneous

saturated clay layer is 150 KPa.

Consolidation test on an undisturbed soil

sample taken from the clay layer showed

that the void ratio decreased from 0.6 to

0.5 by increasing the stress intensity from

100 KPa to 300KPa (a=2.65)

a) The initial void ratio of clay layer isa. 0.209 b. 0.563c. 0.746 d. 1.000


14/21


JH ACADEMY Page 14

b) The total consolidation settlement ofthe clay layer due to the construction

of a structure imposing an additional

stress intensity of 200 KPa is

a. 0.1 m b. 0.25 mc. 0.35 d. 0.5m

136.The equation

can betransformed to

by

substituting

a) b) c) d) e)

137.A saturated clay stratum draining both atthe top and bottom undergoes 50%

consolidation in 16 years under an

applied load. If additional drainage layer

were present at the middle of the clay

stratum, 50% consolidation would occurin

a) 2 yearsb) 4 yearsc) 8 yearsd) 16 years

138.A well of diameter 20 cm fully penetratesa confined aquifer. After a long period of

pumping at rate of 2720 lit/min. The

observations of draw down taken at 10 m

and 100 m distances from the centre of

the well are found to be 3m and 0.5m

respectively. The transmissibility of the

aquifer is

a) 676 dayb) 576 dayc) 526 dayd) 249 day

139.In a consolidated drained tri axial test, aspecimen of clay fails at a cell pressure

of 60 KN/. The effective shearstrength parameters are

KN/

and determine the compressivestrength.

140.and determine the compressivestrength.

141.An un-confined compression test yieldedstrength of 0-1N. If the failure

plane is inclined at

to the horizontal,what are the values of the shear strength

parameters.

142.In a drained tri axial compression testconducted on dry sand, failure occurred

when deviator stress was 218 KN ata confining pressure of 61 KN. Whatis the effective angle of shearing

resistance and inclination of failure plane

to major principle plane?

a) b) c) d)

143.The average friction angle () for ahomogeneous sand deposit is . Theratio of the major and minor principal

stresses at any point in the soil medium,

at failure will be .

144.The appropriate field test to determinethe undrained shear strength of soft clay

is

a) Plate load testb) Static cone penetration testc) Standard penetration testd) Vane shear test

145.A given saturated clay is known to haveeffective strength parameters of KPa and =. A sample of this claywas brought to failure quickly so that nodissipation of the pore water pressures

could occur. At failure it was known that

, = 10KPa and =20KPa

a) Estimate the values of atfailure

b) What was the effective normal stresson the failure plane?

c) What was the value of un drainedshear strength?


15/21


JH ACADEMY Page 15

146.Vane test is normally used fordetermining in situ shear strength of

a) Soft claysb) Sandc) Stiff claysd)

Gravel

147.What is the shear strength in terms ofeffective stress on a plane within a

saturated soil mass at a point where the

total normal stress is 295 KPa and the

pore water pressure 120KPa? The

effective shear strength parameters are

12 KPaAnd =

148.If an element of a stressed body is in astate of pure shear with a magnitude of

80N/, the magnitude of maximumprincipal stress at that location is

a) 80 N/b) 113.14 N/c) 120 N/d) 56.57N/

149.In a drained tri axial compression testconducted on dry sand, failure occurred

when deviator stress was 218 KN

at

a confining pressure of 61 KN. Whatis the effective angle of shearing

resistance and inclination of failure plane

to major principle plane?

e) f) g) h) a)

150.If the effective stress parameters of a soilare =10 KPa and =, the shearstrength on a plane within the saturated

soil mass at a point where the total

normal stress is 300 KPa and pore water

pressure is 150 KPa will be

a) 90.5 KPab) 96.6KPac) 101.5KPad) 105.5KPa

151.If the principal stresses in a twodimensional case are -10 MPa and 20

MPa respectively, then maximum shear

stress at the point is

a) 10 MPab) 15 MPac) 20 MPad)

30 MPa

151.A direct shear test was conducted on acohesion less soil (c=0). Specimen

under a normal stress of 200KN/.The specimen failed at a shear stress

of 100KN/. The angle of internalfriction of soil is

a) 26.6 b) 29.5c) 30.0 d) 32.6

152.An infinite slope, with a slope angleof, is made up of a cohesion lesssoil having and KN/. It experiences seepagewith the water table at the surface. If

the unit weight of water is 10 KN/,the factor of safety against failure,

without seepage and with seepage

will be and

Respectively.

.

153.A slope is to be constructed in a soilfor which 0 and . It is to

be assumed that the water level may

occasionally reach the surface of

slope with seepage taking place

parallel to slope. Determine the

maximum slope angle for a factor ofsafety of 1.5. Assuming a potential

failure surface parallel to the slope.

What would be the factor of safety of

the slope, constructed at this angle, if

the water table should be well below

the surface? The saturated unit weight

is 19 KN/.154.

The vertical stress at depth. Z directly

below the point load P is (K is

constant)

a) b) c) d)


16/21


JH ACADEMY Page 16

155.A slope is excavated to a depth of10m in a deep of 10m in a deep layer

of saturated clay of unit weight 20

KN/ . The relevant shear strengthparameters are KN/ and . The rock edge is at a greatdepth. The Taylor stability co-efficient coefficient for and slope angle is 0.18. the factor ofsafety of the load is

a) 2.0 b) 2.1 c) 2.2 d) 2.3156.A point load of 700 KN is applied on

the surface of thick layer of saturatedclay. Using Boussinesqs elastic

analysis, the estimated vertical stress

(). At a depth of 2m and radialdistance of 1.0m from the point of

application of the load is

a) 47.5 KPab) 47.6 KPac) 47.7 KPad) 47.8 KPa

157.An infinite slope is to be constructedin a soil. The effective stress strength

parameters of the soil are . The saturated unitweight of the slope is 20 KN/. Andthe KN/. Assuming thatseepage is occurring parallel to the

slope, the maximum slope angle for a

factor of safety of 1.5 would be

a) 10.b) 11.c) 12.

14.158.A canal having side slopes 1:1 is

proposed to be constructed in a

cohesive soil to a depth of 10m below

the ground surface. The soil

properties are KPa, e= 1.0, G= 2.65

a) If Taylors stability number, and if the canal flowsfall, the factor of safety with

respect to cohesion against

failure of the canal bank slopeswill be

a. 3.7 b. 1.85 c. 1.0 d. Noneb) If there is a sudden draw down of

water in the canal and if Taylors

stability number for the reduced

value of is 0.126, the factor ofsafety with respect to cohesion

against the failure of bank slopes

will be

a.

1.85 b. 1.18 c. 0.84 d. 0.53

159.For two infinite slopes (one in drycondition and other in submerged

condition) in a sand deposit having

the angle of shearing resistance ,

factor of safety was determined as 1.5

(for both slopes). The slope angles

would have beena) For dry and for

submerged.

b) c) ,d) ,

160.The factor of safety of an infinite soilslope shown in fig having properties

e=0, KN/ and KN/ is approximatelyequal to

a)

0.70b) 0.8c) 1.0d) 1.2

161.The vertical stress at point due tothe point load Q on the ground

surface as shown in fig. is .According to Boussinesqs eqn, the

vertical stress at will bea)

b) c)

d)


17/21


JH ACADEMY Page 17

162.An unsupported excavation is to bemade in a clay layer. If KN/, c= 30KN/and a. Calculate depth of tension cracks

b. Calculate the maximum possibleunsupported depth

c. Draw the active pressuredistribution diagram

163.Two consolidated drained shear testson silt yielded the following data:

0.2 0.46

0.4 0.88

If this material is used as abackfill for a smooth vertical

retaining wall of 10m height,

what is the active earth pressure

at the base of the wall? Density

of the fill is 1.6g/cc.

164.A large scale bearing capacity test ona footing of size 1.05 m at adepth of 1.5 m yielding on ultimate

value of 141 KN unconfined

compressive tests on the soft saturated

clay yielded a strength of 0.03 N/ . =1.6g/cc. How much doesthe test value differ from that

obtained using Terzaghis bearingcapacity equation?

165.For the trial slip circle shown in fig.calculate the factor of safety W= 346

KN/m KN/ 20KN/ radius = 9 m

166.A vertical wall 6 m high above thewater table, retains a soil slope, 18 KN/ c=0, Ka= ?

167.Soils transported by wind are knownas soil.

168.Plot the active earth pressuredistribution on the retaining wall

shown by Rankines theory for datagiven below 10 KN/ KN/ C=15 KN/

169.The total active thrust on a verticalwall 3m high retaining a horizontal

sand backfill KN/,

when the water table is at

the bottom of the wall, will be

a) 30 KN/mb) 35 KN/mc) 40 KN/md) 45 KN/m

170.Compute the intensity of passive earthpressure at a depth of 8 m in cohesion

less sand with an angle of internal

friction of when water rises tothe ground level. KN/,

KN/

171.A vertical excavation was made in aclay deposit having unit weight of 22

KN/. It caved in after the diggingreached 4 m depth. Assuming .Calculate the magnitude of cohesion

172.Two footings, one circular and theother square, are founded on the

surface of a purely cohesion less soil.

The diameter of the circular footing issame as that of the side of the square


18/21


JH ACADEMY Page 18

footing. The ratio of their ultimate

bearing capacities is

a)

b)

c) 1.0d) 1.3

173.To have zero active pressure intensityat the tip of a wall in cohesive soil

one should apply a uniform surcharge

intensity of

a) tan b) cot c) tan d) tan

174.1. Find active earth pressure per meterof wall

2. find location of the resultant line of

action.

175.A plate load test was conducted insand on a 300 mm diameter plate. If

the plate settlement was 5 mm at a

pressure of 100 KPa, the settlement of

a 5 m rectangular footing at thesame pressure will be

a) 9.4 b) 18.6 c) 12.7 d) 17.8176.Estimate the resultant thrust and its

location.

177.Soils that have been deposited fromsuspension in running water are called

.

178.A sample of sand with G=2.65 has aporosity of 40%. Find out the .When fully saturated

when

the degree of saturation is 50%

179.A clay sample has a liquid limit of42.5%, plastic limit of 22.4% and

natural moisture content as 30%.

Determine its plasticity index and

liquidity index.

180.In a shrinkage limit test a 9.6 cccontainer was filled with soil slurry.

The weight of the saturated soil was

17.46 g. The slurry was then

gradually dried first in atmosphere

and then in an oven at a constant

temperature of C. The weight

and volume of the dried soil were

11.58 g and 5.22 cc respectively.

Determine the shrinkage limit of the

soil.

181.A sample of sand taken from a naturaldeposit has a porosity of 35%. For a

volume of 495 cc the dry weights inthe densest and loosest states are 1100

g and 800g respectively. Compute the

relative density of sand assuming the

specific gravity of solids to be 2.65

182.Laboratory sieve analysis was carriedout on a soil sample using complete

set of sieves. Out of 1200 gm of

sample, 480 gm retained on 4.75mm

sieve, 360 gm retained on 2 mm sieve

and 240 gm retained on 75 sieve.Limit and plastic limit of soil are 40%


19/21


JH ACADEMY Page 19

and 20% respectively. Find cc, andclassify the soil according to IS.

183.A barrow pit density is 18 KN/.How many soil required toconstruct an embankment of 200

with KN/.

184.A compaction of an embankment iscarried out in 300mm thick horizontal

layers. The rammer used for

compaction has the foot of area 0.05

sq.m. The energy developed per drop

of the hammer is 40 kg-m. Assuming

50% more energy I each pass due to

overlap, calculate the number of

passes required to developcompactive energy equivalent to

Indian standard (light compaction for

each layer).

185.The end of a clean glass tube isinserted in pure water. What is the

height of capillary rise, if the tube is

a) 0.1 mmb) 0.001 mm in diameter.

186.A sample of soil for a constant headpermeability test yields following

data: dia of permeameter= 7.6 cm.

length of soil sample = 20 cm, head

causing flow = 15 cm, quantity of

water collected in 10 min = 150 cc.

, KN/.Determine

a) Coefficient of permeability incm/s

b) Superficial velocity flowc) Seepage velocity

187.For the cases 1 and 2 of fig determinethe pressure head, elevation head,

total head and head loss at the

entering end, exit end and point X of

the sample.

188.a) What is the quantity of waterflowing per minute?

b) To what height above xx wouldthe water rise in a piezometer

inserted at points 1, 2 & 3?

c) What is the effective stress at midheight of soil A?

Soil A: K= cm/s= 18 KN/

Soil B: K= cm/s

= 20 KN/

189.An deposit of fine sand the watertable is 3m below the ground surface

but the sand up to a height of 1 m

above the water table is saturated by

capillary water. The sand above this

height may be considered dry. For the

sand = 2.68 and =40% calculatethe effective stress at a depth of 8m

190.A falling head permeability test wasperformed on a sand sample and the

following data were recorded. c/s area

of permeameter=100

. Length ofsoil sample is 15 cm. area of stand


20/21


JH ACADEMY Page 20

pipe =1, time taken for the headto fall from 150 cm to 50 cm =8min.

temperature of water= C dry mass

of the soil specimen =2.2 kg and

compute coefficient ofpermeability of the soil for a voidratio of 0.70 and temperature ofC

8.95 mill poises 10.09 mill poises

191.Two rows of sheet piles are driven toa depth of 4.4 m below the bed of a

river to form a coffer dam.

Excavation is then carried out within

the coffer Dam up to a depth of 3.3m

below water level by keeping the areafree from water by pumping. The

river bed is sand with K=3 cm/s and is under lain by an

impermeable stratum at a depth of

6.0m below the river bed. What is the

quantity of flow into the coffer dam

per hour per m. Length of the sheet

pile walls? Is there any danger of

quick condition developing at the

bottom of excavation?

192.An excavated structure with a totalweight of 10,000 KN is supported on

a tower with 4 legs rest on piers

located at the corners of a square 6 m

on a side. What is the vertical stress

increment due to this loading at a

point 7 m beneath the centre of the

structure.

194.Representative samples of a layer ofsilty clay 5 m thick, were tested in aconsolidometer and the following

results were obtained. Initial void

ratio pre consolidationstress =120 KN/ re-compressionindex, , compression index=0.27. estimate the consolidationsettlement if the present average over

burden stress of the layer is 70KN/ and increase in average stressin the layer is 80 KN/

195.A normally consolidated clay layersettled by 20 mm when the effective

stress was increased from 25 KN/to 50 KN/. What will be thesettlement when the effective stress is

increased from 50 KN/ to 100KN/

196.Certain clay has a thickness of 5 m.after 1 year when the clay was 50%

consolidated, 8cm of settlement had

occurred. For similar clay and loading

conditions, how much settlement

would occur at the end of 1 year and 4

years respectively, if the thickness of

this new layer were 25 m.

197.On a reclamination site where thewater table is at the ground surface, a

layer of silty sand, 4 m thick, over lies

a layer of soft clay, 10m thick

underlying the clay layer is sandy

gravel. A 3 m thick layer of fill is to

be laid over the site. Unit wt of fill

=21 KN/, of silty sand=20KN/, of clay=18 KN/. ofclay= 2.2 /KN. of theclay= 0.8year. Calculate theconsolidation settlement of the clay

layer due to the placing of the fill

198.The effective stress shear strengthparameters of a soil are = 25KN/ and . Determine theshearing resistance on a plane within


21/21


JH ACADEMY P 21

a submerged soil mass where the total

normal stress is 328 KN/ and porewater pressure is 114 KN/.

199.A symmetrical 16 pile group in softclay, with unconfined compressivestrength of 40 KN/ is to be used asfoundation for a column. The piles are

300 mm in diameter and 10 m long.

Determine the maximum load the

group can carry with piles failing (i)

individually and (ii) as a block.

200.A precast pile is driven with a drophammer weighing 50 KN with a fall

of 1.5m. the average penetration of

the load carrying capacity of pile

according to engineering newsformula.

Documents

TEST PAPER OF GEOTECH1.docx