Geotechnical Engineering and Soil Mechanics

Question 1 Multiple Choice (Single Answer)

For a saturated sand deposit, the void ratio and the specific gravity of solids are 0.70 and 2.67, respectively. The critical (upward) hydraulic gradient for the deposit would be

0.54
0.98
1.02
1.87

Question 2 Multiple Choice (Single Answer)

Likelihood of general shear failure for an isolated footing in sand decreases with

decreasing footing depth
decreasing intergranular packing of the sand
increasing footing width
decreasing soil grain compressibility

Question 3 Multiple Choice (Single Answer)

The results for sieve analysis carried out for three types of sand, P, Q and R, are given in the adjoining figure. If the fineness modulus values of the three sands are given as FM_P, FM_Q and FM_R, it can be stated that

$FM_Q = \sqrt{FM_P \times FM_R}$
FM_Q = 0.5 (FM_P + FM_R)
FM_P > FM_Q > FM_R
FM_P < FM_Q < FM_R

Question 4 Multiple Choice (Single Answer)

A soil is composed of solid spherical grains of identical specific gravity and diameter between 0.075 mm and 0.0075 mm. If the terminal velocity of the largest particle falling through water without flocculation is 0.5 mm/s, that for the smallest particle would be

0.005 mm/s
0.05 mm/s
5 mm/s
50 mm/s

Question 5 Multiple Choice (Single Answer)

Two geometrically identical isolated footings, X (linear elastic) and Y (rigid), are loaded identically (shown alongside). The soil reactions will

be uniformly distributed for Y but not for X
be uniformly distributed for X but not for Y
not be uniformly distributed for both X and Y
both 2 and 3

Question 6 Multiple Choice (Single Answer)

For a sample of dry, cohesionless soil with friction angle ^_$\phi$, the failure plane will be inclined to the major principal plane by an angle equal to

$\phi$
45°
45° - ^$\phi$/2
45° + ^$\phi$/2

Question 7 Multiple Choice (Single Answer)

A fine grained soil has liquid limit of 60 and plastic limit of 20. As per the plasticity chart, according to IS classification, the soil is represented by the letter symbols

CL
CI
CH
CL-ML

Question 8 Multiple Choice (Single Answer)

Quicksand condition occurs when

the void ratio of the soil becomes 1.0
the upward seepage pressure in soil becomes zero
the upward seepage pressure in soil becomes equal to the saturated unit weight of the soil
the upward seepage pressure in soil becomes equal to the submerged unit weight of the soil

Question 9 Multiple Choice (Single Answer)

In a compaction test, G, w, S and e represent the specific gravity, water content, degree of saturation and void ratio of the soil sample respectively. If y_w represents the unit weight of water and y_d represents the dry unit weight of the soil, the equation for zero air voids line is

$y_d \frac{Gy_w}{1 + Se}$
$y_d \frac{Gy_w}{1 + G_W}$
$y_d y\frac{Gy_w}{e + y_wS}$
$y_d \frac{G_w}{1 + Se}$

Question 10 Multiple Choice (Single Answer)

The e-log p curve shown in the figure is representative of

normally consolidated clay
over consolidated clay
under consolidated clay
normally consolidated clayey sand

Question 11 Multiple Choice (Single Answer)

If ^{$\sigma_h, \sigma_w, \sigma_n$}and ^$\sigma_w$ represent the total horizontal stress, total vertical stress, effective horizontal stress and effective vertical stress on a soil element respectively, the coefficient of earth pressure at rest is given by

$\frac{\sigma_h}{\sigma_w}$
$\frac{\sigma_h}{\sigma_w}$
$\frac{\sigma_w}{\sigma_h}$
$\frac{\sigma_w}{\sigma_h}$

Question 12 Multiple Choice (Single Answer)

A clay soil sample is tested in triaxial apparatus in consolidated-drained conditions at a cell pressure of 100 kN/m². What will be the pore water pressure at a deviator stress of 40 kN/m²?

0 kN/m²
20 kN/m²
40 kN/m²
60 kN/m²

Question 13 Multiple Choice (Single Answer)

The number of blows observed in a Standard Penetration Test (SPT) for different penetration depths are given as follows:


Penetration of sampler	Number of blows
0-150 mm	6
150-300 mm	8
300-450 mm	10

The observed N value is

8
14
18
24

Question 14 Multiple Choice (Single Answer)

Group symbols assigned to silty sand and clayey sand are respectively

SS and CS
SM and CS
SM and SC
MS and CS

Question 15 Multiple Choice (Single Answer)

When a retaining wall moves away from the back-fill, the pressure exerted on the wall is termed as

passive earth pressure
swelling pressure
pore pressure
active earth pressure

Question 16 Multiple Choice (Single Answer)

Compaction by vibratory roller is the best method of compaction in case of

moist silty sand
well graded dry sand
clay of medium compressibility
silt of high compressibility

Question 17 Multiple Choice (Single Answer)

Deposit with flocculated structure is formed when

clay particles settle on seabed
clay particles settle on fresh water lake bed
sand particles settle on river bed
sand particles settle on seabed

Question 18 Multiple Choice (Single Answer)

A precast concrete pile is driven with a 50 kN hammer falling through a height of 1.0 m with an efficiency of 0.6. The set value observed is 4 mm per blow and the combined temporary compression of the pile, cushion and the ground is 6 mm. As per Modified Hiley Formula, the ultimate resistance of the pile is

3000 kN
4285.7 kN
8.333 kN
11905 kN

Question 19 Multiple Choice (Single Answer)

Dilatancy correction is required when a strata is

cohesive and saturated and also has N value of SPT > 15
saturated silt/fine sand and N value of SPT < 10 after the overburden correction
saturated silt/fine sand and N value of SPT >15 after the overburden correction
coarse sand under dry condition and N value of SPT < 10 after the overburden correction

Question 20 Multiple Choice (Single Answer)

The relationship among specific yield (S_y), specific retention (S_r) and porosity ($\eta$) of an aquifer is

S_y = S_r + $\eta$
S_y = S_r – $\eta$
S_y = $\eta$– S_r
S_y = S_r + 2$\eta$

Geotechnical Engineering and Soil Mechanics

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