Soil Exploration

Q. Consider the following properties for a soil sampler:
1. Area ratio should be low.
2. Cutting edge should be thick.
3. Inside clearance should be high.
4. Outside clearance should be low.
The properties necessary for a good quality soil sampler would include

1. 1 and 4
2. 1, 2 and 4
3. 2, 3 and 4
4. 1, 3 and 4

Q. Consider the following statements:
In subsoil exploration programme the term "significant depth of exploration"is up to
1. the width of foundation
2. twice width of foundation
3. the depth where the additional stress intensity is less than 20% of overburden pressure
4. the depth where the additional stress intensity is less than 10% of the overburden pressure
5. hard rock level
Which of these statements is/are correct?

1. 1, 3 and 5
2. 2, 3 and 5
3. 1 and 4
4. 2 and 4

Q. A differential free swell test on a soil gives a value of differential free swell of 40%. What is the degree of swelling?

1. Low
2. Medium
3. High
4. Very high

Q. Consider the following statements:
Lime stabilization of soil leads to
1. Decrease in shrinkage limit.
2. Increase in plastic limit.
3. Decrease in liquid limit.
4. Flocculation of clay particles
Which of the above statements are correct?

1. 1, 2 and 3
2. 1, 2 and 3
3. 1, 3 and 4
4. 2, 3 and 4

Q. During a sampling operation, the drive sampler is advanced 600 mm and the length of the sample recovered is 525 mm. What is the recovery ratio of the sample?

1. 0.125
2. 0.140
3. 0.875
4. 0.143

Q. A good quality undisturbed soil sample is one which is obtained using a sampling tube having an area ratio of

1. 8%
2. 16%
3. 24%
4. 32%

Q. Consider the following statements:
On addition of lime to swelling soils,
1. their liquid limit increases
2. their plastic limit increases
3. their shrinkage limit increases
4. their swelling potential decreases
Which of these statements are correct?

1. 1 and 3 only
2. 1, 2 and 4 only
3. 2, 3 and 4 only
4. 1, 2, 3 and 4

Q. A wet, cohesive subgrade is most effectively stabilized by the addition of

1. cement
2. fly ash
3. bitumen
4. lime

Q. The correct sequence of the increasing order of the disturbance to soil samples obtained from chunk, piston, split spoon and remoulded sampler is

1. piston sampler, chunk sampler, split spoon sampler, remoulded sampler
2. chunk sampler, piston sampler, split spoon sampler, remoulded sampler
3. piston sampler, chunk sampler, remoulded sampler, split spoon sampler
4. chunk sampler, piston sampler, remoulded sampler, split spoon sampler

Q. Assertion (A): Wash boring is recommended to obtain undisturbed soil sample above ground water table.
Reason (R): In wash boring, water pumped through the hollow drill rods emerges through the ports of the chopping bit carrying disintegrated soil fragments.

1. both A and R are true and R is the correct explanation of A
2. both A and R are true but R is not a correct explanation of A
3. A is true but R is false
4. A is false but R is true

Q. A soil sampler has inner and outer radii of 25 mm and 30 mm, respectively. The area ratio of the sampler is

1. 24%
2. 34%
3. 44%
4. 54%

Q. For good quality soil sample:
1. Area ratio should be low
2. Inside clearance should be low
3. Cutting edge should be thick
4. Outside clearance should be high

Which of the above statement(s) is/are correct?

1. 1 and 2
2. 2 and 4
3. 1, 2 and 3
4. 1, 3 and 4

Q. Match List-I(Sampler) with List-II (Use) and select the correct answer using the codes given below the lists:
List-I
A. Split spoon sampler
B. Stationary piston sampler
C. Rotary sampler
D. Compressed air sampler
List-II
1. To obtain representative samples in all types of soil
2. To obtain undisturbed samples of sands below water table
3. To obtain undisturbed samples in clay and silts
4. To obtain approximately undisturbed samples of hard cemented cohesive soils

1. A- 1, B - 3, C - 2, D - 4
2. A- 3, B - 1, C - 4, D - 2
3. A- 1, B - 3, C - 4, D - 2
4. A- 3, B - 1, C - 2, D - 4

Q. Which technique of stabilization for the sub-base is preferred for a heavy plastic soil?

1. Cement stabilization
2. Mechanical stabilization
3. Lime stabilization
4. Bitumen stabilization

Q. Consider the following statements:
1. Increase in volume of a soil sample without external constraints on submergence in water is termed as the 'free swell of soil.'
2. Clay soil rich in montmorillonite exhibits very low swelling characteristic.
3. Generally, free swell of soil sample ceases when its water content reaches the plastic limit.
Which of these statements are correct?

1. 1 and 2
2. 1 and 3
3. 2 and 3
4. 1, 2 and 3

Q. Match List-1 (type of boring) with List-II (suitability) and choose the correct answer using the codes given below:

List-I	List-II
P. Auger Boring	1. Gravelly and bouldery stratum
Q. Wash Boring	2. For all types of soil except bouldery stratum
R. Percussion Boring	3. For all types of soil above GWT

1. P - 1, Q - 3, R - 2
2. P - 2, Q - 3, R - 1
3. P - 3, Q - 2, R - 1
4. P - 1, Q - 2, R - 3

Q. Consider the following statements:
1. Obtaining reliable properties of soil is very important in geotechnical engineering. Chunk samples obtained from the field are the best for this purpose.
2. Chunk samples may easily be obtained at all depths below ground level and for all types of soils.
3. Undisturbed soil samples are enclosed in rugged containers. As such, they do not get disturbed easily during transportation and handling.
Which of these statements is/are correct?

1. 1, 2 and 3
2. 1 only
3. 2 and 3
4. 1 and 3

Q. Consider the following statements:
1. Buried service lines should be avoided in an expansive soil region.
2. A swelling pressure less than $20kN/m^2$ is not of much consequence.
3. If soil is not black in colour, it is unlikely to be an expansive soil.
Which of these statements are correct?

1. 1, 2 and 3
2. 1 and 2 only
3. 2 and 3 only
4. 1 and 3 only

Q. In seismic exploration method, velocities $V_1$ and $V_2$ were 600 m/s and 4000 m/s. The distance corresponding to the break point of velocities was 30 m. Based on this detail, what is the depth of overburden?

1. 11.5 m
2. 12.5 m
3. 12.9 m
4. 13.2 m

Q. A sampling tube with a cutting edge is used for extracting the samples. The sampling tube has the following dimensions:
$\text{Inner diameter of cutting edge}=D_c$
$\text{Outer diameter of cutting edge}=D_w$
$\text{Inner diameter of the sampling tube}=D_s$
$\text{Outer diameter of the sampling tube}=D_t$
What is the area ratio $A_r$ of the sampling tube ?

1. $A_r=\frac{D_w^2-D_c^2}{D_c^2}\times 100\%$
2. $A_r=\frac{D_t^2-D_c^2}{D_c^2}\times 100\%$
3. $A_r=\frac{D_t^2-D_w^2}{D_w^2}\times 100\%$
4. $A_r=\frac{D_t^2-D_s^2}{D_s^2}\times 100\%$

Q. Consider the following statements related to the properties of a good quality soil sample:
1. Area ratio should be low
2. Cutting edge should be thick
3. Inside clearance should be low
4. Outside clearance should be low
Which of the above statements are correct?

1. 1 and 2
2. 2 and 3
3. 3 and 4
4. 1 and 4

Q. Consider the following statements:
1. The static cone penetration test is unsuitable for layered deposits of sands, silts and clays.
2. The results of groundwater investigation are recorded as water-table contours over the site.
3. Closed piezometers are used to measure pore water pressure in soils having low permeability.
Which of the above statements are correct?

1. 1, 2 and 3
2. 1 and 2 only
3. 2 and 3 only
4. 1 and 3 only

Q. Consider the following statements:
Foundation design in expansive soil can be done by
1. isolating the foundation from the swelling soil
2. taking measures to prevent the swelling
3. employing measures to make the structure withstand the movement
Which of these statements is/are correct?

1. 1 and 2 only
2. 2 and 3 only
3. 1 and 3 only
4. 1, 2 and 3

Q. Consider the following statements relating to foundations on expansive soils:
1. Strength should be improved and compressibility should be reduced.
2. Compressibility should be increased.
3. No stabilization should be done.
Which of these statements is/are correct?

1. 1, 2 and 3
2. 2 only
3. 1 only
4. 3 only

Q. Consider the following statements:
1. A differential free swell value of 40% indicates a soil with a high degree of expansiveness.
2. A swelling pressure of less than $20kN/m^2$ is not of much consequence.
3. The swelling pressure is a unique parameter for a swelling soil and is not influenced by other factors.
Which of these statements is/are correct?

1. 1, 2 and 3
2. 1 and 2 only
3. 2 and 3 only
4. 1 only

Q. Match List-I (Type of exploration) with List-II (Soil profile) and select the correct answer using the codes given below the lists:
List-I
A. Diamond core drilling
B. Uncased wash boring
C. Open pit excavation
D. Cased boring
List-II
1. Medium strong cohesive soils
2. Rocky formation
3. Soft cohesive soils and cohesionless soils.
Exploration up to relatively large depths
4. Exploration up to a shallow depth below ground level

1. A - 4, B - 3, C - 2, D - 1
2. A - 2, B - 1, C - 4, D - 3
3. A - 4, B - 1, C - 2, D - 3
4. A - 2, B - 3, C - 4, D - 1

Q. Which of the following tests are essential for designing a foundation on expansive soils?
1. Swelling pressure test
2. Free swell test
3. Estimation of differential free swell
4. Shrinkage limit test
Which of the above statements are correct?

1. 1, 2 and 3 only
2. 1, 2 and 4 only
3. 1, 2, 3 and 4
4. 2, 3 and 4 only

Q. Consider the following statements:
Prevention or elimination of swelling can be brought by
1. providing an impervious apron around the structure
2. pre-wetting the ground to a moisture content equal to equilibrium moisture content
3. packing downward loads large enough to exceed swelling pressures
4. chemically stabilizing the soil with lime
Which of these statements are correct?

1. 1 and 2
2. 1 and 3
3. 2 and 3
4. 1, 2, 3 and 4

Q. Match List-I with List-II and select the correct answer using the code given below the lists:
List-I
A. Geophysical methods
B. SPT
C. DCPT
D. Piston-type sampler
List-II
1. Primarily for cohesive soils
2. Clays and silts
3. Reconnaissance covering large area and large depth
4. Suitable for sandy soils

1. A - 2 , B - 1, C - 4, D - 3
2. A - 3 , B - 1, C - 4, D - 2
3. A - 2 , B - 4, C - 1, D - 3
4. A - 3 , B - 4, C - 1, D - 2

Q. Consider the following statements:
1. Undisturbed samples may be obtained with the help of augers.
2. Auger drilling is most effective in clayey soils.
3. Hollow stem augers are sometimes used to drill holes in silty sand.
Which of these statements are correct?

1. 1, 2 and 3
2. 1 and 2 only
3. 2 and 3 only
4. 1 and 3 only