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Past Questions
Bearing capacity of soil depends upon ______ of particles
A)
Shape
B)
Cohesion
C)
Size
D)
Specific gravity
Bearing capacity of soil is strongly influenced by the particle size because particle size affects the soil’s density, frictional resistance, and interlocking between grains. Coarser soils generally have higher bearing capacity than fine-grained soils due to better drainage and greater shear strength.
Why the others are incorrect:
- Specific gravity: It is a property of the soil solids, but it is not the primary factor governing bearing capacity.
- Cohesion: Cohesion affects bearing capacity in cohesive soils, but the question asks about a property of particles; among the given options, size is the most direct particle-related factor.
- Shape: Particle shape can influence interlocking and friction, but particle size has a more direct and significant effect on bearing capacity in standard soil mechanics context.
In stability computations of slope, the curve representing the real surface of sliding is usually represented by
A)
Parabola
B)
Arc of circle
C)
Cubic parabola
D)
None of these
In slope stability analysis, the actual or assumed failure surface (surface of sliding) is commonly idealized as an arc of a circle, especially for homogeneous slopes and in classical limit equilibrium methods. This circular slip surface is the standard representation used in many engineering computations.
Why the others are incorrect:
- Parabola: A parabolic slip surface is not the usual assumption in standard slope stability computations.
- Cubic parabola: This is not a conventional representation of the failure surface in slope stability analysis.
- None of these: Incorrect because the commonly used representation is the arc of a circle.
A temporary rigid structure having platforms to enable masons to work at different height of a building, is known as
A)
Scaffolding
B)
Dead shore
C)
Raking shore
D)
Underpining
Scaffolding is a temporary rigid framework erected around or alongside a building to provide working platforms at different heights for masons and other workers. It is specifically used to support workers and materials during construction, repair, or maintenance. Underpinning is the strengthening of an existing foundation, not a working platform. Dead shore is a vertical support used to carry loads from a structure during repairs, and raking shore is an inclined support used to stabilize a wall or structure; neither provides platforms for working at height.
The thickness of the edge of plain and reinforced foundation on soil shall not be less than
A)
200mm
B)
175mm
C)
150mm
D)
250mm
The minimum thickness at the edge of a plain or reinforced foundation resting on soil is **150 mm**. This is the standard minimum value used in foundation design to ensure adequate structural integrity and durability at the footing edge.
Why the other options are incorrect:
- **175 mm**: Not the standard minimum specified for foundation edge thickness.
- **200 mm**: Greater than the minimum, but not the required lower limit asked in the question.
- **250 mm**: Also larger than the minimum and therefore not the correct answer.
Hence, the correct option is **(c) 150 mm**.
The geological factors that determine the degree of stability of slope is
A)
Type of rocks
B)
Orientation of bedding planes and joints
C)
The presence of faults & folds
D)
All of these
The stability of a slope is controlled by several geological factors, including the type of rock, the presence of faults and folds, and the orientation of bedding planes and joints. These features affect the strength of the rock mass and the likelihood of sliding or failure, so the correct answer is "All of these." Option (a) is incomplete because rock type alone does not determine stability. Option (b) is also incomplete because bedding/joint orientation is important but not the only factor. Option (c) is incorrect because faults and folds are only one of the contributing factors, not the full set.
Rain water is safe for drinking if
A)
Rain water is not exposed to sun
B)
Rainwater is stored in ferro cement tank
C)
Rainwater is disinfected through chlorination
D)
All of these
Rainwater becomes safe for drinking only after proper disinfection, such as chlorination, because collected rainwater may contain dust, microbes, and other contaminants. Option (c) is therefore correct. Option (a) is incorrect because merely avoiding sunlight does not make water potable. Option (b) is incorrect because storing rainwater in a ferro-cement tank improves storage but does not by itself disinfect the water. Hence, (d) is also incorrect because not all the listed conditions make rainwater safe for drinking.
Gravity wall comprising a series of stacked members creating hollow cells filled with soil or rock is known as
A)
Dry masonry retaining wall
B)
Grid walls
C)
Crib walls
D)
Geogrids
Crib walls are gravity retaining walls made of a series of interlocking stacked members (usually timber, concrete, or steel) that form hollow cells, which are then filled with soil or rock. This matches the description exactly.
Why the others are incorrect:
- Geogrids are synthetic reinforcement materials used to stabilize soil, not a wall type made of stacked hollow cells.
- Dry masonry retaining wall is a wall built from stones without mortar; it does not consist of cellular stacked members filled with soil/rock.
- Grid walls is not the standard term for this retaining wall system in civil engineering; the correct term is crib wall.
Specific capacity is a quantity
A)
Which determines how a waterwell dries up in a drawdown
B)
Which a waterwell can produce per unit drawdown
C)
Which determines the rate of recharging of a waterwell
D)
None of these
Specific capacity of a well is defined as the discharge (yield) of the well per unit drawdown, i.e., Q/s. So option (b) is correct: it is the quantity a water well can produce per unit drawdown. Option (c) is incorrect because specific capacity does not measure recharge rate; it reflects well performance under pumping. Option (a) is incorrect because it does not describe how a well dries up. Option (d) is incorrect because option (b) is the standard definition.
A plot between rainfall intensity versus time is called
A)
Hydrograph
B)
Mass curve
C)
Hyetograph
D)
Isohyets
A plot of rainfall intensity against time is called a **hyetograph**. It shows how rainfall intensity varies during a storm event.
Why the others are incorrect:
- **Hydrograph**: plot of stream discharge (or stage) versus time, not rainfall intensity.
- **Mass curve**: plot of cumulative rainfall versus time.
- **Isohyets**: lines on a map joining points of equal rainfall depth over an area.
The maximum pressure which a soil can bear without causing shear failure is termed as
A)
Safe Bearing Pressure
B)
Ultimate Bearing Pressure
C)
Failure Capacity
D)
Ultimate Shearing Capacity
The maximum pressure a soil can sustain at the foundation level before shear failure occurs is called the **ultimate bearing pressure** (or ultimate bearing capacity). It represents the limiting pressure at which the soil fails in shear.
Why others are incorrect:
- **a) Safe Bearing Pressure**: This is the allowable pressure after applying a factor of safety to the ultimate bearing pressure, so it is lower than the failure value.
- **c) Failure Capacity**: Not the standard geotechnical term used for this definition.
- **d) Ultimate Shearing Capacity**: This refers to shear strength in general, but the specific term for pressure a soil can bear without shear failure is **ultimate bearing pressure**.
If the Plasticity Index of a soil is less than 7, the soil may be classified as
A)
Highly Plastic
B)
Medium Plastic
C)
Low Plastic
D)
Non-Plastic
A Plasticity Index (PI) less than 7 indicates very low plasticity, and such soils are generally classified as non-plastic or nearly non-plastic. Hence, option d is correct.
Why the others are incorrect:
- a) Highly Plastic: This corresponds to a much higher PI, not less than 7.
- b) Medium Plastic: Medium plastic soils have a moderate PI range, above the non-plastic/low-plastic range.
- c) Low Plastic: While PI less than 7 suggests low plasticity, in standard exam classification it is commonly taken as non-plastic or nearly non-plastic; therefore d is the best answer.
Isobar is a line which joins points of equal
A)
Rainfall depth
B)
Temperature
C)
Humidity
D)
Atmosphere pressure
An isobar is a line on a weather map joining points of equal atmospheric pressure, so option d is correct. Option b is incorrect because lines of equal temperature are called isotherms. Option c is incorrect because equal humidity is represented by isohumes (or isohydric lines in some contexts). Option a is incorrect because equal rainfall depth is shown by isohyets.
In an under reinforced beam section,
A)
Steel is insufficient
B)
Steel yields first before failure
C)
Concrete is crushed first before failure
D)
Steel and concrete fail at the same time
In an under-reinforced beam section, the amount of tensile steel provided is less than the balanced amount. Therefore, when the beam is loaded, the steel reaches its yield stress first and undergoes large plastic deformation before the concrete in compression reaches its crushing strain. This is the desired ductile failure mode in RCC design.
Why the other options are incorrect:
- a) "Steel is insufficient" is a vague statement and not the defining behavior; the key point is that the steel yields first.
- c) "Concrete is crushed first before failure" describes an over-reinforced section, not an under-reinforced one.
- d) "Steel and concrete fail at the same time" describes a balanced section, not an under-reinforced section.
For sand having an internal friction of 30o, the ration of passive to active lateral earth pressure will be
A)
1
B)
3
C)
9
D)
6
For a cohesionless soil (sand), Rankine’s earth pressure coefficients are:
Ka = tan^2(45° - φ/2) and Kp = tan^2(45° + φ/2).
Given φ = 30°, we get:
Ka = tan^2(30°) = (1/√3)^2 = 1/3
Kp = tan^2(60°) = (√3)^2 = 3
Hence, the ratio of passive to active lateral earth pressure is Kp/Ka = 3 ÷ (1/3) = 9.
Therefore, the correct option is c (9).
Why others are incorrect:
- a (1): would imply passive and active pressures are equal, which is not true.
- b (3): this is only the passive coefficient Kp, not the ratio Kp/Ka.
- d (6): does not match the Rankine earth pressure relation for φ = 30°.
A well-graded soil has co-efficient of expansion between
A)
4 to 5
B)
1 to 3
C)
3 to 4
D)
3.5 to 4
A well-graded soil has a coefficient of expansion typically in the range of 3 to 4. This indicates a balanced distribution of particle sizes, which gives moderate expansion characteristics. Option (c) is therefore correct.
Why the others are incorrect:
- (b) 1 to 3: This range is too low and is more consistent with poorly expansive or very coarse soils.
- (a) 4 to 5: This is higher than the usual range for well-graded soil and suggests greater expansion than expected.
- (d) 3.5 to 4: This is too narrow and does not represent the standard textbook range as accurately as 3 to 4.
If the terrace area is 100 sq.m and annual rainfall is 1000mm and harvest efficiency is 60%, the amount of rainwater that can be harvested is
A)
42,000 litres
B)
70,000 litres
C)
60,000 litres
D)
62,000 litres
Rainwater harvested = terrace area × annual rainfall × harvest efficiency.
Given:
- Area = 100 sq.m
- Rainfall = 1000 mm = 1 m
- Efficiency = 60% = 0.6
So, harvested volume = 100 × 1 × 0.6 = 60 m³.
Since 1 m³ = 1000 litres, volume = 60,000 litres.
Therefore, the correct option is c) 60,000 litres.
Why others are incorrect:
- d) 62,000 litres: does not match the calculation.
- a) 42,000 litres: too low; would require a much smaller efficiency or rainfall.
- b) 70,000 litres: too high; exceeds the computed harvested volume.
Advantage of sausage wall over normal stone masonry wall is/are
A)
Sausage wall can undergo large deformation without crackling & are flexible.
B)
Sausage wall did not allow free drainage of water.
C)
The cost is cheaper for the same height in comparison to normal stone masonry wall.
D)
Sausage wall is easier to construct than stone masonry retaining wall.
Sausage walls are made of wire-mesh cages filled with stones (gabion-type construction). Their main advantage over normal stone masonry walls is flexibility: they can undergo large deformation and settle without cracking, which makes them suitable where ground movement or differential settlement may occur.
Why the others are incorrect:
- b: This is not an advantage. Sausage walls are generally permeable and allow drainage, which is one of their benefits.
- c: While they may sometimes be economical, the key recognized advantage is flexibility and deformation capacity, not simply lower cost.
- d: They are often easier and faster to construct than conventional stone masonry retaining walls, but the most correct and standard advantage asked here is flexibility without cracking.
If the curve of the failure passes through the toe, the failure is knows as
A)
Face failure
B)
Base failure
C)
Toe failure
D)
Foundation failure
The correct answer is **Toe failure**. In slope stability, when the failure surface passes through the **toe** of the slope, it is specifically called a **toe failure**.
Why the others are incorrect:
- **Base failure**: This refers to a deeper failure surface passing below the base of the slope, not just through the toe.
- **Foundation failure**: This is a more general term and is not the standard name for a slip surface passing through the toe.
- **Face failure**: This occurs when the failure surface lies within the slope face and does not pass through the toe.
Choose the most appropriate type of foundation in a soil of low bearing capacity or where columns are closely spaced in both directions
A)
Strip Foundation
B)
Pad Foundations
C)
Bearing Piles
D)
Raft Foundations
Raft foundations are the most appropriate where the soil has low bearing capacity or where columns are closely spaced in both directions. A raft (mat) spreads the load from many columns over a large area, reducing contact pressure on the weak soil and minimizing differential settlement. Pad foundations are isolated footings for individual columns and are not suitable when the soil is weak or columns are crowded. Strip foundations are used mainly for load-bearing walls or a row of closely spaced columns in one direction, not in both directions. Bearing piles transfer load to deeper, stronger strata, but the question asks for the most appropriate foundation type for closely spaced columns on low bearing soil, which is typically a raft foundation.
Weep holes are provided in the retaining walls
A)
To reduce active earth pressure on the walls
B)
To reduce the built up hydrostatic pressure
C)
To provide better compaction
D)
To increase passive earth pressure
Weep holes are provided in retaining walls to drain out water that accumulates behind the wall. This prevents the build-up of hydrostatic pressure, which can greatly increase the lateral load on the wall and may cause instability or failure. Hence, option (b) is correct.
Why the others are incorrect:
- (a) Active earth pressure is due to soil movement and is not directly reduced by weep holes.
- (c) Weep holes have nothing to do with compaction; they are drainage openings.
- (d) Passive earth pressure is resistance offered by soil in front of a structure and is not increased by weep holes.
Pavement walls is defined as
A)
Permanent structure to prevent subsidence that commonly occurs near water ways.
B)
Permanent structure built to prevent erosion of earth cutting slopes on the road.
C)
Permanent structure covering earth filling behind retaining walls.
D)
All of these
Pavement walls are permanent protective structures used in road works to support and protect earthwork and prevent damage such as subsidence, erosion of cut slopes, and failure of earth fill/retaining arrangements. Hence all the listed descriptions refer to functions associated with pavement walls, so option d is correct. Option a is correct because such walls can prevent subsidence near waterways; option b is correct because they protect earth cutting slopes from erosion; option c is also correct because they may cover/protect earth filling behind retaining walls.
Field shear test for clays in which a vane consisting of two or more blades fixed at right angles is used is known as ________ test
A)
Bearing
B)
Unconfined Compression
C)
Vane
D)
Penetration
The test described is the **vane shear test**. In this field shear test for soft clays, a vane made of two or more blades fixed at right angles is inserted into the soil and rotated to measure the undrained shear strength.
Why the others are incorrect:
- **a) Bearing**: Bearing tests determine bearing capacity of soil, not shear strength using a vane.
- **b) Unconfined Compression**: This is a laboratory compression test on cohesive soils, not a field vane test.
- **d) Penetration**: Penetration tests (like SPT or CPT) measure resistance to penetration, not the vane-based shear strength test described here.
If fck is the characteristic strength of the concrete, the strength of concrete in the actual structure shall be taken as
A)
0.87 fck
B)
0.67 fck
C)
0.75 fck
D)
0.80 fck
The strength of concrete in the actual structure is taken as 0.67 fck. This is the commonly used design value to account for the difference between characteristic cube strength and the effective strength considered in structural design. Hence option (b) is correct.
Why the others are incorrect:
- 0.87 fck: This is not the standard factor used for actual structural concrete strength.
- 0.80 fck: Not the prescribed reduction factor for this purpose.
- 0.75 fck: Also not the accepted value for strength of concrete in the actual structure.
Therefore, the correct answer is (b) 0.67 fck.
Total active pressure due to dry backfill, acting at H/3 above the base is directly proportional to
A)
H³
B)
H
C)
H²
D)
H1/2
For a dry backfill, the active earth pressure intensity varies linearly with depth: p = K_a \gamma z. Hence the total active thrust on a wall of height H is the area of the triangular pressure diagram: P_a = 1/2 \times (K_a \gamma H) \times H = 1/2 K_a \gamma H^2. Therefore, the total active pressure is directly proportional to H^2, and it acts at H/3 above the base. Option c is correct.
Why the others are incorrect:
- a (H^3): would correspond to a quantity involving moment or a higher-order distribution, not the resultant thrust.
- b (H): pressure intensity at the base is proportional to H, but the total thrust is the area under the pressure diagram, so it is proportional to H^2, not H.
- d (H1/2): no such dependence arises in active earth pressure for dry backfill.
In a rectangular water tank, maximum Bending Moment occurs when the depth of water tank is equal to ________ the length of the short wall
A)
One- fourth
B)
One – third
C)
One – half
D)
Three – fourth
For a rectangular water tank, the short wall behaves like a vertical cantilever retaining water. The bending moment at the base due to hydrostatic pressure is proportional to the square of the water depth, and the standard design condition for maximum bending moment in the short wall occurs when the water depth is equal to one-half of the length of the short wall. Hence, the correct answer is option (c) One-half.
Why the others are incorrect:
- (a) One-fourth: too small; it does not correspond to the standard maximum bending moment condition.
- (b) One-third: not the governing ratio for maximum bending moment in the short wall.
- (d) Three-fourth: too large; this would not represent the maximum bending moment condition for the short wall.