Probable questions for GATE 2015

Geotechnical Engineering-Probable Question for GATE 2015

Department of Civil Engineering, MIT Moradabad

Multiple Choice Questions

for GATE 2015

CIVIL ENGINEERING

GEOTECHNICAL ENGINEERING

DEPARTMENT OF CIVIL ENGINEERING

MIT, MORADABAD

Prepared by:

N. K. SINGH, H.O.D., CE

PRADEEP KUMAR(ASST. PROF.)

A. K. BANSAL (ASST. PROF.)



SOIL TYPES & FORMATIONS, PROPERTIES OF SOIL, SOIL

CLASSIFICATION AND SOIL STRUCTURE

Q.1 According to IS classification, the range of silt size particles :

(a) 4.75 mm to 2.0 mm (b) 2.0 mm to 0.425 mm

(c) 0.425 mm to 0.075 mm (d) 0.075 mm to 0.002 mm

Q .2 Which of the following type of soil is transported by gravitational forces :

(a) looss (b) talus

(c) drift (d) dune sand

Q .3 Consider the following statements in the context of aeolian soils :

(1) The soil has low density and low compressibility

(2) The soil is deposited by wind

(3) The soil has large permeability

Which of these statements are correct :

(a) 1, 2 and 3 (b) 2 and 3 (c) 1 and 3 (d) 1 and 2

Q.4 Bentonite is a material obtained due to the weathering :

(a) Limestone (b) quartzite (c) Volcanic ash (d) Shales

Q.5 For a sandy soil with soil grains spherical in shape and uniform in size, what is

the theoretical void ratio :

(a) 0.61 (b) 0.71 (c) 0.91 (d) 0.81

Q.6 A clay sample has a void ratio 0.54 in dry state. The specific gravity of soil

solids is 2.7. what is the shrinkage limit of the soil :

(a) 8.5% (b)0.0% (c) 17.0% (d) 20.0%



Q.7 Match list I with list II and select the correct answer using the codes given

below the lists :

List – I

A. Casagrande’s apparatus

B. Hydrometer

C. Plate load test

D. Oedometer

List – II

E. Determination of grain size distribution

F. Consolidation Characteristics

G. Determination of Consistency limits

H. Determination of safe bearing capacity of soil.

Codes :

A B C D

(a) E G F H

(b) E G H F

(c) G E F H

(d) G E H F

Q.8 The natural void ratio of a sand sample is 0.6 and its density index is 0.6. If its

void ratio in the loosest state is 0.9. Then the void ratio in the density state will be :

(a) 0.2 (b) 0.3 (c) 0.4 (d) 0.5

Q.9 A soil has bulk density of 22 kN/m3 and water content 10%. The dry density is:

(a) 20 kN/m3

(b) 15 kN/m3 (c) 18 kN/m

3 (d) 19 kN/m

3

Q.10 Select the correct range of density index ID :

(a) ID>0 (b) ID≥0 (c) 0<ID<1 (d) 0≤ID≤1



Q.11 The ratio of the shear strength of undistributed soil to that of remoulded soil

is known as the :

(a) liquidity index (b) activity

(c) relative consistency (d) sensitivity

Q.12 The ratio of saturated unit weight to dry unit weight of a soil is 1.25. If the

specific gravity of solids (GS) is 2.65, the void ratio of the soil :

(a) 0.625 (b) 0.665 (c) 0.944 (d) 1.325

Q.13 The water content of a saturated soil and the specific gravity of soil solids

were found to be 30% and 2.70, respectively. Assuming the unit weight of water to

be 10 kN/m3, the saturated unit weight (kN/m

3) and the void ratio of the soil are:

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

Q.14 The saturated unit weight of the sand (kN/m3) is :

(a) 15 (b) 18 (c) 21 (d) 24

# Following Statemet dues 15 & 16-

Statement :- Laboratory sieve analysis was carried out on a soil sample using a

complete set of standard IS sieves, out of 500 gm of soil used in the test, 200gm

was retained on IS 600µ sieve, 250gm was retained on IS 500µ sieve and the

remaining 50gm was retained on IS 425µ sieve.

Q.15 The coefficient of uniformity of the soil is :

(a) 0.9 (b) 10 (c) 1.1 (d) 1.2

Q.16 The classification of soil is :

(a) SP (b) SW (c) GP (d) GW

Q.17 The liquid limit (LL), Plastic limit (PL) and shrinkage limit (SL) of a

cohesive soil satisfy the relation :

(a) LL>PL<SL (b) LL>PL>SL (c) LL<PL<SL (d) LL<PL>SL



Q.18 Stoke’s law is valid only if the size of the particle is :

(a) b/w 0.2mm and 0.0002mm (b) greater than 0.2mm

(c) less than 0.0002mm (d) all of the above

Q.19 If the plasticity index of a soil mass is zero. The soil is :

(a)looss (b) clayey site (c) silt (d) sand

Q.20 For a given soil sample if Cc=1 and Cu=4, then the value of D30/D10 would be:

(a) 2.00 (b) 1.75 (c) 1.50 (d) 1.25

Q.21 Valid range for S, the degree of satu ratio of soil is in % is :

(a) S>0 (b) S≤0 (c) 0<S<100 (d) 0≤S≤100

Q.22 By placing a soil sample at 1050C for 24 hours in an oven.

A. hydroscopic moisture is lost

B. capillary water is lost

C. free water is lost

D. structural water is lost

Which of the above statements are correct :

(a) 1,2 and 4 (b) 3 and 4 (c) 1,2,3 and 4 (d) 1,2 and 3

Q.23 Match list- I with list- II and select the correct answer using codes given

below the lists :

List – I

A. ML

B. SM

C. Pt

D. MH

List – II

E. silty sand

F. inorganic silt with large compressibility



G. inorganic silt with small compressibility

H. soil with high organic content with high compressibility

Codes:-

A B C D

(a) G F H E

(b) H E G F

(c) G E H F

(d) H F G E

Q.24 A soil mass contains 40% gravels, 50% sand and 10% silt. This soil can be

classified as :

(a) silty sandy gravel having coefficient of uniformity less than 60.

(b) silty gravelly sand having coefficient of uniformity equal to 10.

(c) gravelly silty sand having coefficient of uniformity greater than 60.

(d) gravelly silty sand and its coefficient of uniformity cannot be

determined.

Q.25 the correct sequence of plasticity of minerals in soil is an increasing :

(a) silica, kaolinite, illite, montmorillonite

(b) kaolinite, silica, illite, montmorillonite

(c) silica, kaolinite, montmorillonite, illite

(d) kaolinite, kaolinite, silica, montmorillonite, illite

Q.26 Among the clay minerals, the one having the maximum swelling tendency is :

(a) kaolinite (b) illite (c) montmorillonite (d) halloysius



Principle of effective stress ,capillarity & permeability ,seepage analysis

Q.1 In a falling head permeability test on a soil, the time taken for the head to fall

from h0 to h1 is t. the test is repeated with same initial head h0. The final head h’ is

noted in time t/2. Which one of the following equations gives the relation b/w h’,

h0 and h1 :

(a) h’=h0/h1 (b) h’= (h0/h1)1/2

(c) h’=h0h1 (d) h’= (h0h1)1/2

Q.2 Approximate ratio of the permeabilities of two clean soils having D10=0.6mm

and D10=0.3mm respectively is :

(a) 4.0 (b) 3.75 (c) 4.25 (d) 3.5

Q.3 The coefficient of permeability increases When :

(a) The viscosity of fluid increases

(b) The viscosity of fluid decreases

(c) The temperature condition decreases

(d) length of sample is decreased.

Q.4 Determination of coefficient of permeability by means of a field pumping test

can be done for :

(a) soft clay (b) sandy soil (c) stiff clay (d) marine clay

Q.5 Affective stress in a soil is the stress carried by :

(a) soil mass as whole

(b) pore water present in the voids

(c) air present in the void

(d) solids present in the soil mass



Q.6 Due to rise in temperature, the viscosity and the unit weight of the percolating

fluid are reduced to 60% and 90% respectively. If other things remain constant, the

coefficient of permeability :

(a) increases by 25%

(b) increases by 50%

(c) increases by 33.3%

(d) decreases by 33.3%

Q.7 In a falling head permeability test, the time taken for the head to fall from

27cm to 3cm is 10 minutes, if the test is repeated with the same initial head i.e.

27cm, what time would it take for the head to fall to 9cm :

(a) 3 minutes (b) 5 minutes (c) 6 minutes (d) 7.5 minutes

Q.8 Consider the following statements :-

Capillary water in soils

A. causes negative pore water pressure

B. reduces effective pressure

C. increases bearing capacity

D. reduces bearing capacity

Which of true statements are correct :

(a) A and C (b) A and D (c) B and C (d) B and D

Q.9 The water level in a lake is 5m above the bed. The saturated unit weight of the

lake bed soil is 20 kN/m3. The unit weight of the lake bed soil is 10 kN/m

3. The

effective vertical stress at 5m depth below the lake bed is :

(a) 50kN/m3 (b) 75kN/m

3 (c) 100 kN/m

3 (d) 150 kN/m

3

Q.10 In a soil deposit of three layers of equal thickness, the permeabilities of first

second and third layers are in the ratio of 1:2:3. The ratio of average permeability

in horizontal direction (Kh) to that in the vertical direction (Kv) will be :



(a) 22:18 (b) 18:22 (c) 24:12 (d) 12:24

Q.11 Which one of the following is correct in respect of pore water pressure µ and

effective stress , in the soil just below the bottom of a pond due to a 2m rise in

water level in the pond :(u=pore water pressure ,Ϭ =effective stress)

(a)u ≤ increases by 20kN/m2 and Ϭ remains unaltered

(b) u increases by 20kN/m2 and Ϭ decreases by 20kN/m

2

(c) u decreases by 20kN/m2 and Ϭ remains unultered

(d) both u and Ϭ remain unaltered.

Q.12 A flow net of a coffer dam foundation has 6 flow channels and 18

equipotential drops. The head of water lost during seepage is 6m. if the coefficient

of permeability of foundation is 4 X 10-5

m/min, then the seepage loss/m length of

dam will be :

(a) 2.16 X 10-2

m3/day

(b) 6.48 X 10-2

m3/day

(c) 11.52 X 10-2

m3/day

(d) 34.56 X 10-2

m3/day

Q.13 Capillary rise is maximum for :

(a) coarse grained soils

(b) well graded soils

(c) fine grained soils

(d) gap graded soils

Q.14 Water is flowing in an upward direction through a stratum of sand, 4m thick,

under a total head difference of 2m. The sand has a specific gravity of 2.65 and

void ratio of 0.065. The factor of safety against quick sand condition would be :

(a) 3 (b) 1.0 (c) 1.5 (d) 2.0



Q.15 For design of filter the criteria usually adopted is :

(a) D15 of filter/ D85 of base materials < 4 to 5

(b) D15 of base materials / D85 of filter < 4 to 5

(c) D15 of filter /D85 of base materials > 40

(d) D85 of filter/ maximum opening of pipe of drain < 2

Q.16 In an earther dam the phereatic line is :

(a) straight line (b) circular line (c) parabolic line (d) zigzag line

Q.17 Darey’s law for flow through soil is valid if Reynold’s no. is less than :

(a) 4000 (b) 3000 (c) 2000 (d) 1

Q.18 The critical gradient of a soil ic is given by :

(a) G-1/1-e (b) G+1/1+e (c) G-1/1+e (d) G+1/1-e

Q.19 Which one of the following explains the flow condition accuring with in a

soil when its effective pressure is reduced to zero :

(a) Laminar flow condition

(b) quick sand condition

(c) liquefaction condition

(d) stratified condition

Q.20 To provide safety against piping failure with a factor of safety of 5, what

should be the maximum permissible exit gradient for soil with specific gravity of

2.5 and porosity of 0.35 :

(a) 0.155 (b) 0.167 (c) 0.195 (d) 0.213

Q.21 During seepage through an earth dams the direction of seepage is :

(a) parallel to the equipotential lines

(b) perpendicular to the stream lines



(c) perpendicular to the equipotential lines

(d) along the direction of gravity

Q.22 A soil has a discharge velocity of 6 X 10-7

m/s and a void ratio of 0.5. its

seepage velocity is :

(a) 18 X 10-7

m/s (b) 12 X 10-7

m/s (c) 6 X 10-7

m/s (d) 3 X 10-7

m/s

Q.26 For the soil strata shown in figure , 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 in effective vertical

pressure in kPa at mid height of clay layer will be

G S

2m zone of capillary saturation after drainage

GWT after drainage

10m Silty sand ϒsat= 22KN/m3

7m clay ϒsat= 19KN/m3

(a) 0.2 (b) 2 (c) 20 (d) 200

Stress distribution in soils, compressibility & consolidation

Q.1 Ϭz is the vertical stress at a depth equal to z in the soil mass due to surface

point load Q .The vertical stress at depth equal to 2z will be

(a) 0.25Ϭz

(b) 0.50Ϭz

(c) 1.0Ϭz



(d) 2.0Ϭz

Q.2 The intensity of vertical pressure ,directly below a concentrated load of 3/2π

tonnes at depth of 3/2π metres is given by

(a) 1.5t/m2

(b) 1.0t/m2

(c) (3/2π)1.5

t/m2

(d) (3/2π)2.5

t/m2

Q.3 Newmark’s influence chart is used for

(a) rectangular loading condition

(b) loaded area of any shape

(c) strip loading

(d) circular loaded area

Q.4 Influence factor I depends on

(a) applied vertical load

(b)Types of soil

(c)Location of point with respect to load

(d) soil modulus

Q.5 Boussinesq’s influence factor for vertical z and at centre of a circular area of

diameter A carrying uniformily distributed load is

(a) 1-[1/1+(A/2Z)2]

3/2

(c)3/2π[1/1+(A/Z)2]

5/2

(d)1-[1/1+(A/Z)2]

3/2

Q.6 Match list-I with list-II and select the correct answer using the codes given

below the lists:

List-I

A. Stress distribution due to point load in homogeneous isotropic medium

B. Stress distribution due to point load in an anisotropic soil medium



C. Influence chart for stress distribution in a rectangular area

D. Influence chart for stress distribution in irregularly shaped areas.

List-II

1. Stein Brenner

2. Newmark

3.Boussinesq

4. Westergaard

Codes:

A B C D

(a) 4 3 2 1

(b) 3 4 2 1

(c) 3 4 1 2

(d) 4 3 1 2

Q.7 Consider the following statements :

1 . coefficient of consolidation normally increases with decreasing liquid limit

of clay .

2.The larger the value of coefficient of consolidation , the longer it takes for

full consolidation to occur.

Which of these statements is/are correct?

(a) 1 only

(b) 2 only

(c) both 1 and 2

(d) neither 1 nor 2

Q.8 The settlement analysis for clay layer draining from top and bottom shows a



Settlement of 2.5cm in 4 years and an ultimate settlement of

10cm.however detailed subsurface investigation reveals that there is no

drainage at the bottom. The ultimate settlement in this condition will be

(a) 2.5cm

(b) 5cm

(c) 10cm

(d) 20cm

Q.9 Coefficient of consolidation is used to calculate

(a) time rate of settlement

(b) total settlement

(c) pre consolidation pressure

(d) stress in the soil

Q.10 Rate of consolidation

(a) increases with decreases in temperature

(b) increases with increases in temperature

(c) is independent of temperature

(d) is unaffected by permeability of soil

Q.11 When the primary consolidation process in a soil is complete ,then

(a) the hydrostatic pressure will become zero

(b) the excess pore water pressure will become zero

(c) both the hydrostatic and excess pore water pressure will become zero

(d) the effective stress will become zero

Q.12 A Normally consolidation clay layer settles by 25mm when the effective

stress is increased from 15kPa to 30kPa .if the effective stress is later increased

further from 30kPa to 60kPa, then the additional settlement would be

(a) 25mm

(b) 50mm



(c) 75mm

(d) 100mm

Q.13 when the degree of consolidation is 50%, the time factor is about

(a) 0.2

(b) 0.5

(c) 1.0

(d) 2.0

Q.14 In consolidation testing , curve fitting method is used to determine

(a) compression index

(b) swelling index

(c) coefficient of consolidation

(d) time factor

Q.15 the ultimate consolidation settlement of a structure resting on a soil

(a) decreases with the increases in the initial void ratio

(b) decreases with the decreases in the plastic limit

(c) increases with the increases in the initial void ratio

(d) increases with the decreases in the porosity of soil

Q.16 The unit of the coefficient of consolidation is

(a) cm2/gm

(b) cm2/sec

(c) gm/cm2/sec

(d) gm-cm/sec

Q.17 If the time required for 50% consolidation of a remoulded sample of clay

with single drainage is t, then the time required to consolidate the same sample of

clay with same degree of consolidation but with double drainage is

(a) t/4



(b) t/2

(c) 2t

(d) 4t

Q.18 Cofficient of consolidation for clays normally

(a) decreases with increases in liquid limit

(b) increases with increases in liquid limit

(c) first increases and then decreases with increases in liquid limit

(d) remains constant at all liquid limits

Q.19 Given that for an over consolidation clayey soil deposit ,the pressure under

which the deposit has been fully consolidation in the past is 125KN/m2 and the

present overburden pressure is 75KN/m2,the OCR of the soil deposit

(a) 75/125

(b) 50/75

(c)125/75

(d) 200/75

Q.20 The change that takes place during the process of consolidation of a saturated

clay would include

(a) an increase in pore water pressure and an increases in effective pressure

(b) an increase in pore water pressure and a decreases in effective pressure

(c) a decrease on pore water pressure and a decreases in effective stress

(d) a decrease in pore water pressure and an increase in effective pressure

Q.21 Which one of the following soils has stress-strain response similar to that of

dense sand? (OCR stands for consolidation ratio)

(a) over consolidated clays having high OCR

(b) over consolidated clays having low OCR

(c) normally consolidated clays



(d) unconsolidated clays

Q.22 Sand drains are used to

(a) reduce the settlement

(b) accelerate the consolidation

(c) increasing the permeability

(d) transfer the load

Q.23 The time for clay layer to achieve 90% consolidation is 15 years. The time

required to achieve 90% consolidation if the layer was twice as thick ,3 times more

permeable and 4 times more compressible would be

(a) 60 years

(b) 75 years

(c) 80 years

(d) 85 years

Q.24 Consider the following processes involved in consolidation

1. Void reduction

2. Pore pressure development

3. Seepage of water

4. Creep

What is correct sequence of the processes given above?

(a) 4-1-3-2

(b) 2-3-1-4

(c) 4-3-1-2

(d) 2-1-3-4

Q.25 for a certain loading condition ,a saturated clay undergoes 40% consolidation

in period of 178 days. What would be the additional time required for further 20%

consolidation to occur?

(a) 89 days

(b) 222.5 days

(c) 329.5 days)

(d) 400.5 days



Q.26 At a reclamation site for which the soil is shown in figure , a 3m thick layer

of a fill material is to be laid instantaneously on the top surface .if the coefficient of

volume compressibility , mv for clay is 2.2x 10 -4 m

2/kN , the consolidation

settlement of the clay layer due to placing of fill material will be

3m fill material ϒsat= 21KN/m3

G ▼ GWT

4m silty sand ϒsat= 20KN/m3

10m clay ϒsat= 18KN/m3 mv= 2.2x10

-4m

2/kN

(a) 69.5mm (b) 139mm (c) 228mm (d) 278mm

Shear strength of soil, stability of earth slopes, lateral earth pressure

&retaining wall

Q.1 which one of following conditions is valid in case of unconfined compression

test in comparison to tri-axial test?

(a )minor principal stress =0

(b) minor principal stress =0.5x major principal stress

(c) minor principal stress = major principal stress

(d) major principal stress =3x minor principal stress

Q.2 which one of the following is appriopriate tri-axial test to assess the

immediate stability of an unloading problem ,such as an excavation of clay slope?

(a) UU test

(b) CU test

(c) CD test

(d) unconsolidated drained tests



Q.3 In a tri- axial test at failure ,major principal stress was 180kPa, and minor

principal stress was 100kPa ,and pore pressure was 20 kPa .The sine of angle of

shearing resistance of the sandy soil tested is

(a) 1/3

(b) 2/7

(c) 1/2

(d) 1/6

Q.4 For saturated soil ,skempton’s B-Parameter is

(a) nearly zero (b) nearly 0.5

(c) nearly 1.0 (d) very high

Q.5 The stresses responsible for mobilisation of shearing strength of soil is

(a) effective normal stress

(b) neutral stress

(c) total normal stress

(d) shear stress

Q.6 In a direct shear test, the shear stress and normal stress on a dry sand sample at

failure are 0.6kg/cm2 and 1kg/cm

2 respectively. The angle of internal friction of

the sand will be nearly :

(a) 25®

(b) 31®

(c) 37®

(d) 43®

Q.7 A dense dry sand sample under tri-axial test has the confining pressure of

20t/m2.the angle of internal friction is 35

®.the sample will fail at normal pressure

of about:

(a) 30.5t/m2

(b) 31.5t/m2

(c) 32.5t/m2



(d) 33.5t/m2

Q.8 Unconfined compressive strength test is:

(a) Undrained test

(b) drained test

(c) consolidated undrained test

(d) consolidated drained test

Q.9 The ratio of the undisturbed shear strength to the remoulded shear strength in

cohesive soil under undrained conditions is

(a) zero

(b) 1

(c) greater than 1

(d) between 0 and 1

Q.10 The unconfined compressive strength of a pure clay soil is 100KN/m2.What

is the value of cohesion of soil in KN/m2?

(a) 200

(b) 100

(c) 75

(d) 50

Q.11 Match list-I (field test) with list-II (useful for) and select answer using the

codes given below the lists:

List-I

A. Vane shear test

B. Standard penetration test

C. Static cone penetration test

D. Pressure meter test

List-II

1. End bearing and skin friction resistance



2. In-situ sress-strain characteristics

3. Soft clay

4. Sandy deposits

Codes:

A B C D

(a) 4 2 1 3

(b) 3 4 1 2

(c) 4 3 2 1

(d) 3 4 2 1

Q.12 A vane 20cm long and 10cm in diameter was pressed into a soft marine clay

at the bottom of a bore hole .torque was applied gradually and failure occurred at

1000kg-cm.the cohesion of the clay in kg/cm2 is

(a) 1/π x 6/7

(b) 1/π x 5/7

(c) 1/π x 4/7

(d) 1/π x 3/7

Q.13 During the first stage of tri-axial test when the cell pressure is increased from

0.10N/m2 to 0.26N/m

2, the pore water pressure increases from 0.07N/mm

2 to

0.15N/mm2.Skempton’s pore pressure parameter B is

(a) 0.5

(b) -0.5

(c) 2.0

(d) -2.0

Q.14 An initial cross –sectional area of a clay sample was 15cm2. The failure strain

was 25% in an unconfined compression test .the corrected area of the sample at

failure would be

(a) 15cm2

(b) 20cm2

(c) 25cm2



(d) 30cm2

Q.15 In a shear test on cohesionless soils ,if the initial void ratio is less than critical

void ratio ,the sample will

(a) increase in volume

(b) initially increase in volume and then remain constant

(c) decrease in volume

(d) initially decrease and then increase in volume

Q.16 A finite slope of cohesionless soil is safe as long as

(a) there is no external load

(b) β < φ

(c) β > φ

(d) the soil is dry

Q.17 In the friction circle method the radius of the friction circle is given by

(a) r tan φ

(b) r cos φ

(c) r sin φ

(d) r

Q.18 If the unit weight of soil is 20KN/m3 cohesion is 15KN/m

2,factor of safety is

1.5 and the stability number is 0.05, the safe maximum height of the slope is

(a) 5.0m

(b) 8.0m

(c) 10.m

(d) 12.0m

Q.19 An excavation was made at a slope angle of 54® in homogeneous clay.when

the depth of excavation reached 8m,a slip occurred .the slip surface was likely to

have passed through a point:

(a) above the toe of the slope

(b) below the toe

(c) through the toe

(d) near the mid –point of the slope

Q.20 Coulomb’s theory of earth pressure is based on



(a) the theory of plasticity

(b) the theory of elasticity

(c) empirical rules

(d) wedge theory

Q.21 For a sand having an internal friction of 30® ,the ratio of passive to active

lateral earth pressure will be

(a) 1

(b) 3

(c) 6

(d) 9

Q.22 The nature of earth pressure above dredge line behind a cantilever sheet pile

wall is

(a) active

(b) passive

(c)at rest

(d) active and passive

Q.23 To stabilize a concrete cantilever retaining wall against sliding , the ratio of

sliding force to resisting force should be

(a) ≥ 1.55

(b) ≤ 1.55

(c) ≥ 1.0

(d) ≤ 0.645

Q.24 The pore water pressure in the capillary zone is

(a) zero

(b) positive

(c) negative

(d) very low

Q.25 What is the critical depth of a vertical cut in a saturated cohesive soil with

c=1.5t/m2 and ϒ=1.8t/m

3

(a) 0.83m

(b) 1.67m

(c) 2.50m

(d) 3.33m



Q.26 A retaining wall 8m high with a smooth vertical back retains a clay backfill

with c=15KN/m,φ=15® and ϒ=8KN/m

3.(given sin 15

®=0.25). the pressure at the

top will ,nearly ,be equal to

(a) 35.2KN/m2

(b) 23.0KN/m2

(c) 27.6KN/m2

(d) 11.5Kn/m2

Q.27 Consider the following assumptions :

1. failure occurs on a plane surface.

2. wall is smooth but not necessarily vertical

3. failure wedge is a rigid body.

Coulomb’s theory of earth pressure is based on assumptions

(a) 1,2and 3

(b) 1 and 2

(c) 1 and 3

(d) 2 and 3

Q.28 A saturated stiff clay has unit weight 2gm/cm3 and unconfined compressive

strength 2kg/cm2.the depth of tension crack that would develop in this clay is

(a) 2m

(b) 5m

(c) 10m

(d) 20m

Q.29 Rankine’s theory of earth pressure assumes that the back of the wall is

(a) plane and smooth

(b) plane and rough

(c) vertical and smooth

(d) vertical and rough

Bearing capacity & shallow foundation , pile foundation, soil exploration



Q.1 The net ultimate bearing capacity of purely cohesive soil

(a) depends on the width of the footing and is independent of the depth of

the footing

(b) depends on the width as well as the depth of footing

(c) depends on the depth , but is independent of the width ,of the footing

(d) is independent of both the width and the depth of footing

Q.2 If an SPT test gave the average blow count of 32 in fine sand below

water table ,then what is the corrected value of blow count?

(a) 22.1

(b) 23.5

(c) 24.2

(d) 24.8

Q.3 Match list-I (Types of foundation) with list-II (Suitability) and select the

correct answer using the codes given below the lists:

List-I

A. Spread footings

B. Under reamed piles

C. Raft foundation

D. Deep foundations

List-II

1. Soft clay for 20m followed by hard rock stratum

2. Up to 3m black cotton soil followed by medium dense sand

3. Compact sand deposit extending to great depth

4. Loose sand extending to great depth

Codes:

A B C D

(a) 4 1 3 2

(b) 3 2 4 1

(c) 4 2 3 1

(d) 3 1 4 2



Q.4 A test plate 30cm square , settles by 12mm under a load of 4.5kN in a sandy

soil . by how much will a footing 2m x 2m subjected to a load of 200KN settle?

(a) 36.3mm

(b) 20.87mm

(c) 75.7mm

(d) 18.15mm

Q.5 When a load test was conducted by putting a 60cm square plate on top of a

sandy deposit , the ultimate bearing capacity was observed as 60KN/m2. What is

the ultimate bearing capacity for a strip footing of 1.2m width to be placed on the

surface of the same soil?

(a) 75KN/m2

(b) 120KN/m2

(c) 150KN/m2

(d) 160KN/m2

Q.6 The ultimate bearing capacity of square footing on surface of a saturated clay

having unconfined compression strength of 50KN/m2 (using skempton’s equation)

is

(a) 250KN/m2

(b) 180KN/m2

(c) 150KN/m2

(d) 125KN/m2

Q.7 Sinking effort in well foundation is the ratio of weight of well staining to that

of skin friction developed on the sides and should preferably be

(a) < 1.0

(b) =1.0



(c) > 1.0

(d) > 2.0

Q.8 According to terzaghi’s theory ,the net ultimate bearing capacity of clay is

given by

(a) cNq

(b) cNg

(c) cNc

(d) 1.2cNc

Q.9 The ultimate bearing capacity of a footing is reduced by 50% when the

position of water table is

(a) at the base of footing at ground surface

(b) at ground surface

(c) at a depth equal to 1.5 times the depth of foundation

(d) at a depth equal to 0.5 times the depth of foundation

Q.10 According to Terzaghi’s theory ,the ultimate bearing at ground surface for a

strip footing in purely cohesive soil is given as

(a) 2.57C

(b) 5.14C

(c) 5.7C

(d) 6.2C

Q.11 If the weight of excavated soil is equal to superimposed load ,then the

foundation is known as

(a) Balanced foundation

(b) Floating foundation

(c) Well foundation

(d) Raft foundation



Q.12 The SPT value is recorded for the penetration of split barrel sampler for a

penetration of

(a) 15cm

(b) 30cm

(c) 45cm

(d) 60cm

Q.13 A raft foundation with a basement floor is placed at a depth of 4m below

ground level. The superstructure imposes a load of 150KN/m2 on the raft. The unit

weight of soil is 20KN/m3. what are the values of the gross and net loading

pressure on the soil, respectively?

(a) 230KN/m2 , 150KN/m

2

(b) 150JN/m2 , 230KN/m

2

(c) 150KN/m2 , 70KN/m

2

(d) 80KN/m2 , 150KN/m

2

Q.14 The bearing capacity of strip footing on a saturated clay is 120KN/m2. The

bearing capacity of a circular footing (diameter=width) will be

(a) more than 120KN/m2

(b) equal to 120KN/m2

(c) less than 120KN/m2

(d) any of the above

Q.15 Allowable bearing pressure for a foundation depends upon

(a) Allowable settlement only

(b) Ultimate bearing capacity of soil only

(c) Both allowable settlement and ultimate bearing capacity

(d) None of above

Q.16 In the plate load test for determining the bearing capacity of soil, the size of

square bearing plate should be



(a) less than 300mm

(b) between 300mm and 750mm

(c) between 750mm and 1m

(d) greater than 1m

Q.17 A 300mm square bearing plate settles by 15mm in a plate load test on a

cohesive soil when the intensity of loading is 0.2N/mm2. The settlement of a

prototype shallow footing 1m square under the same intensity lo loading is

(a) 15mm

(b) 30mm

(c) 50mm

(d) 167mm

Q.18 As per terzaghi’s equation, the bearing capacity of strip footing resting on

cohesive soil (c=10KN/m2) for unit depth and unit width (assume NC as 5.7) is

(a) 47KN/m2

(b) 57KN/m2

(c) 67KN/m2

(d) 77KN/m2

Q.19 The allowable bearing capacity at 25mm allowable settlement for a footing

in a sandy soil is 15t/m2. The allowable bearing capacity for the same footing

permitting a settlement of 40mm is

(a) 24t/m2

(b) 30t/m2

(c) 35t/m2

(d) 40t/m2

Q.20 The minimum slope of the well curb in well foundation should be (V: H)

(a) 1: 2

(b) 1: 1



(c) 2: 1

(d) 3:1

Q.21 Consider the following statements about the under-reamed pile in swelling

soils:

1. Its bulb provides anchor against movement due to volume changes of soil.

2. It is a driven pile

3. Its bulb diameter is 2.5 times its shaft diameter

Which of these statements are correct?

(a) 1,2 and 3

(b) 1 and 2 only

(c) 2 and 3 only

(d) 1 and 3 only

Q.22 Consider the following statements :

1.Piles are provided in groups , which are connected together by a pile cap. The

structure rests on top of the pile cap. The pile cap is situated below the ground

level .

2. for situations where pile is subjected to upward pull, pedestal piles or under-

reamed piles are more suitable type of foundations.

Which of these statements is / are correct?

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

Q.23 A square pile of section 30cm x 30cm and length 10m penetrates a deposit of

clay having c=5KN/m2 and the mobilizing factor ɋ=0.8. what is the load carried by

the pile by skin friction only?

(a) 192KN

(b) 75KN

(c) 60KN



(d) 48KN

Q.24 The settlement ratio of pile group is generally

(a) less than 0.25

(b) between 0.5 and 0.75

(c) between 0.75 and 1.00

(d) more than 1.00

Q.25 A single acting stream hammer weighing 22.5KN and falling through a height

of 1.2m drives a pile . if the final set is 12.5mm , then according to engineering

news formula.

(a) allowable load for the pile is 300KN

(b) ultimate bearing capacity of the pile is 300Kn

(c) allowable load for the pile is 200kN

(d) ultimate bearing capacity of the pile is 120Kn.

Q.26 Negative skin friction on a pile under vertical compressive load acts

(a) downwards and increases the load carrying capacity of pile

(b) downwards and reduces the load carrying of pile

(c) upwards and increases the load carrying capacity of pile

(d) downwards and maintains the same load carrying capacity of pile

Q.27 During a sampling operation , the drive sampler is advanced 600mm and the

length of the sample recovered is 525mm. what is the recovery ratio of the sample.

(a) 0.125

(b) 0.140

(c) 0.875

(d) 0.143

Q.28 A soil sampler has inner and outer radii of 25mm and 30mm , respectively.

The area ratio of the sampler is



(a) 24%

(b) 34%

(c) 44%

(d) 54%

Q.29 Which techniques of stabilization foe sub base is preferred for heavy plastic

soils?

(a) cement stabilization

(b) mechanical stabilization

(c) lime stabilization

(d) bitumen stabilization

Q.30 At a site having a deposit of dry sandy soil, an average soil of standard

penetration resistance N equal to 6 was recorded . the compactness of the soil

deposit can be described as

(a) very loose

(b) dense

(c) medium

(d) loose

ANSWER KEY

Soil types & formations, properties of soil, soil classification and soil

structure

1.a 2.b 3.b 4.c 5.c 6.d 7.d 8.c 9.a 10.d 11.d 12.b 13.a

14.c 15.d 16.a 17.b 18.a 19.d 20.a 21.d 22.d 23.c 24.c 25.a 26.c

Principle of effective stress ,capillarity & permeability ,seepage analysis

1.d 2.a 3.b 4.a 5.d 6.b 7.b 8.a 9.a 10.a 11.a 12.c 13.b

14.a 15.a 16.c 17.d 18.c 19.b&c 20.c 21.c 22.a 23.b 24.c

25.a 26. c



Stress distribution in soils, compressibility & consolidation

1.(a) 2. (b) 3. (b) 4. (c) 5. (a) 6. (c) 7. (a) 8. ( c) 9. (a)

10. (b) 11. (b) 12. (a) 13. (a) 14. (c) 15. (a) 16. (b) 17. (a) 18. (a)

19. (d) 20. (c) 21. (a) 22. (b) 23. (c) 24. (b) 25. (b) 26. (b)

Shear strength of soil, stability of earth slopes, lateral earth pressure

&retaining wall

1.(a) 2.(a) 3. (a) 4. (c) 5 . (a) 6. (b) 7. (b) 8. (a) 9. (c)

10. (d) 11. (b) 12. (a) 13. (a) 14. (b) 15. (d) 16. (b) 17. (c) 18. (c)

19. (b) 20. (c) 21. (d) 22. (d) 23. (a) 24. (c) 25. (d) 26. (b) 27. (c)

28. (c) 29. (c)

Bearing capacity & shallow foundation , pile foundation, soil exploration

1.(d) 2. (b) 3. (b) 4. (a) 5. (c) 6. (c) 7. (d) 8. (c) 9. (b)

10. (c) 11. (a) 12. (b) 13. (a) 14. (a) 15. (c) 16. (b) 17. (c) 18.(b)

19. (a) 20. (b) 21. (d) 22. (c) 23. (d) 24. (d) 25. (a) 26. (b) 27. (c)

28. (c) 29. (c) 30. (d)

Probable questions for GATE 2015

Education

Transcript of Probable questions for GATE 2015