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AMIE Section B Civil study materials
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AMIE Section B Civil practice questions

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Question 1Civil Engineering

In a simply supported beam carrying a uniformly distributed load over its entire span, where does the maximum bending moment occur?

  1. At the supports
  2. At the quarter points
  3. At midspan Correct answer.
  4. At the point of contraflexure

Explanation

For a simply supported beam with a uniform load, the bending moment diagram is parabolic with zero values at both supports and its peak at the centre. The maximum sagging moment equals wL squared divided by eight. The point of contraflexure is where moment is zero, not maximum.

Question 2Civil Engineering

What is the standard unconfined compressive strength test specimen shape used for soil classification purposes?

  1. A prism of square cross-section
  2. A sphere of 38 mm diameter
  3. A cylinder with height twice its diameter Correct answer.
  4. A cube of 50 mm side

Explanation

The unconfined compression test uses a cylindrical specimen whose height is approximately twice its diameter to limit end effects. This geometry ensures a reasonably uniform stress distribution through the sample. Cubes, prisms and spheres are not standard for this test.

Question 3Civil Engineering

Which constituent of ordinary Portland cement is chiefly responsible for early strength gain?

  1. Tricalcium silicate Correct answer.
  2. Tricalcium aluminate
  3. Dicalcium silicate
  4. Tetracalcium aluminoferrite

Explanation

Tricalcium silicate hydrates rapidly and governs the early strength development of cement paste, typically within the first four weeks. Dicalcium silicate reacts slowly and contributes mainly to long-term strength. Tricalcium aluminate controls setting and heat evolution rather than strength.

Question 4Civil Engineering

In surveying, what does a benchmark represent?

  1. A reference line for setting out curves
  2. A station where a horizontal angle is measured
  3. A fixed point of known reduced level Correct answer.
  4. A temporary turning point used for levelling

Explanation

A benchmark is a permanent, stable point whose reduced level has been accurately determined and recorded. It serves as the datum reference from which other levels are derived during levelling operations. Turning points and angle stations are temporary or operational, not fixed references.

Question 5Civil Engineering

What is the primary purpose of providing a slump cone test on fresh concrete?

  1. To assess workability or consistency Correct answer.
  2. To determine the compressive strength
  3. To measure the water-cement ratio
  4. To estimate the density of hardened concrete

Explanation

The slump test measures the consistency of fresh concrete by recording the drop of the slumped heap. It is an empirical indicator of workability and ease of placing. Strength, density and the water-cement ratio are determined by other tests or mix design calculations.

Question 6Civil Engineering

Which type of foundation is most suitable for transferring heavy loads from a structure to a deep, strong bearing stratum beneath weak surface soil?

  1. Isolated footing
  2. Raft foundation
  3. Pile foundation Correct answer.
  4. Strip footing

Explanation

Pile foundations transmit loads through weak upper deposits to a competent stratum at depth by skin friction or end bearing. Isolated and strip footings rely on shallow soil and would settle excessively over weak ground. A raft spreads load over a large area but does not reach a deep bearing layer.

Question 7Civil Engineering

What is the standard design life commonly assumed for ordinary buildings in structural design codes?

  1. 10 years
  2. 50 years Correct answer.
  3. 25 years
  4. 200 years

Explanation

Ordinary buildings are generally designed for a nominal working life of about fifty years, which underpins characteristic load and durability provisions. Monumental or special structures may adopt longer periods. Ten and twenty-five years are typical for temporary works, and two hundred years is unusual.

Question 8Civil Engineering

Which property of a fluid is defined as its resistance to gradual shear deformation?

  1. Surface tension
  2. Bulk modulus
  3. Viscosity Correct answer.
  4. Capillarity

Explanation

Viscosity quantifies a fluid's internal resistance to shear flow and relates shear stress to the velocity gradient. It governs energy losses in pipes and channels. Surface tension, bulk modulus and capillarity describe other distinct fluid behaviours.

Question 9Civil Engineering

A rectangular beam 200 mm wide and 400 mm deep is subjected to a bending moment of 12 kN·m. What is the maximum bending stress in the section?

  1. 9.00 N/mm²
  2. 2.25 N/mm² Correct answer.
  3. 4.50 N/mm²
  4. 1.13 N/mm²

Explanation

The section modulus equals bd squared divided by six, giving 200 times 400 squared over six, about 5.33 million mm cubed. Dividing the moment of 12 million N·mm by this modulus yields approximately 2.25 N/mm squared. This is the extreme fibre stress in bending.

Question 10Civil Engineering

A soil sample has a void ratio of 0.65 and the specific gravity of solids is 2.65. What is the saturated unit weight closest to?

  1. 21.0 kN/m³
  2. 14.2 kN/m³
  3. 19.6 kN/m³ Correct answer.
  4. 16.8 kN/m³

Explanation

Saturated unit weight equals the unit weight of water times the sum of specific gravity and void ratio divided by one plus void ratio. Substituting 9.81 times (2.65 plus 0.65) over 1.65 gives about 19.6 kN per cubic metre. This assumes all voids are water-filled.

Question 11Civil Engineering

In a pipe flow, the Reynolds number is 3500. What is the expected flow regime?

  1. Laminar flow
  2. Ideal irrotational flow
  3. Creeping flow
  4. Transitional or turbulent flow Correct answer.

Explanation

The critical Reynolds number for pipe flow is about 2000, above which disturbances grow and turbulence develops. A value of 3500 lies in the transitional zone bordering fully turbulent flow. Laminar flow persists only below the lower critical value.

Question 12Civil Engineering

A simply supported beam of span 6 m carries a central point load of 40 kN. What is the maximum bending moment?

  1. 40 kN·m
  2. 60 kN·m Correct answer.
  3. 120 kN·m
  4. 80 kN·m

Explanation

For a central point load, the maximum moment occurs at midspan and equals the load times the span divided by four. Here 40 times 6 over 4 gives 60 kN·m. The reaction at each support is 20 kN, and the moment at midspan is that reaction times half the span.

Question 13Civil Engineering

In a concrete mix, reducing the water-cement ratio while maintaining workability by using a plasticiser will generally:

  1. Reduce strength while increasing permeability
  2. Increase permeability and reduce strength
  3. Have no effect on strength or permeability
  4. Increase compressive strength and reduce permeability Correct answer.

Explanation

Lower water-cement ratio reduces capillary porosity, which raises compressive strength and lowers permeability. Plasticisers restore workability so the reduction can be achieved without placing difficulty. Durability generally improves as a result.

Question 14Civil Engineering

In a closed traverse, the sum of the interior angles of a five-sided polygon should equal:

  1. 540 degrees Correct answer.
  2. 720 degrees
  3. 360 degrees
  4. 900 degrees

Explanation

The interior angles of a closed polygon with n sides sum to (n minus 2) times 180 degrees. For five sides this gives 3 times 180, equal to 540 degrees. Any discrepancy from this total indicates angular misclosure.

Question 15Civil Engineering

A rectangular channel 3 m wide carries a discharge of 6 m³/s at a depth of 1 m. What is the Froude number approximately?

  1. 0.90
  2. 2.00
  3. 1.28
  4. 0.64 Correct answer.

Explanation

Velocity equals discharge divided by area, giving 6 over 3, or 2 m/s. Hydraulic depth equals area divided by top width, which is 3 over 3, or 1 m. Froude number equals velocity divided by the square root of gravity times depth, about 2 over 3.13, giving roughly 0.64.

Question 16Civil Engineering

In limit state design of reinforced concrete, partial safety factors are applied to loads and material strengths primarily to:

  1. Account for uncertainties and ensure adequate reliability Correct answer.
  2. Satisfy aesthetic requirements
  3. Simplify architectural detailing
  4. Reduce the cost of construction

Explanation

Partial safety factors cover variability in loads, material strengths, and construction tolerances so that the probability of failure remains acceptably low. They convert characteristic values into design values for comparison of effects and resistance. Cost, aesthetics and detailing are not their purpose.

Question 17Civil Engineering

A clay layer consolidates under a load. Which condition corresponds to the end of primary consolidation?

  1. When the load is first applied
  2. When the soil reaches its liquid limit
  3. When excess pore pressure has essentially dissipated Correct answer.
  4. When the water table rises

Explanation

Primary consolidation is governed by the gradual dissipation of excess pore water pressure and transfer of stress to the soil skeleton. The process ends when excess pore pressure becomes negligible. Secondary compression may then continue at a slow rate.

Question 18Civil Engineering

Which test is most appropriate for determining the shear strength parameters of a saturated clay under undrained conditions?

  1. Unconsolidated undrained triaxial test Correct answer.
  2. Standard Proctor test
  3. Constant head permeability test
  4. Sieve analysis

Explanation

The unconsolidated undrained triaxial test measures undrained shear strength without allowing drainage, which matches short-term field loading of saturated clay. It yields the undrained cohesion directly. Proctor, permeability and sieve tests address compaction, flow and grading respectively.

Question 19Civil Engineering

Why is the effective stress concept central to soil mechanics?

  1. It measures the water content of the soil
  2. It governs strength, compressibility and volume change of soils Correct answer.
  3. It determines the colour and texture of the soil
  4. It defines the total load carried by the soil mass

Explanation

Effective stress equals total stress minus pore water pressure, and it controls frictional resistance, deformation and volume change in soils. Strength and consolidation behaviour are expressed in terms of effective stress rather than total stress. It does not describe water content or appearance.

Question 20Civil Engineering

In a singly reinforced concrete beam, increasing the lever arm between the compressive and tensile resultants, while keeping the steel area constant, will:

  1. Have no effect on the moment of resistance
  2. Cause the section to become over-reinforced
  3. Reduce the moment of resistance
  4. Increase the moment of resistance Correct answer.

Explanation

The moment of resistance equals the tensile force multiplied by the lever arm. With steel area and stress unchanged, a larger lever arm produces a proportionally larger resisting moment. The section remains under-reinforced as long as the steel yields first.

Question 21Civil Engineering

A cantilever retaining wall is to be checked for stability. Which pair of failure modes must be verified?

  1. Segregation and bleeding
  2. Buckling and fatigue
  3. Overturning and sliding Correct answer.
  4. Creep and shrinkage

Explanation

Retaining walls must resist overturning about the toe and sliding along the base, in addition to bearing capacity and settlement checks. These two checks ensure the wall remains stable under lateral earth pressure. Buckling, creep and segregation relate to other structural or material phenomena.

Question 22Civil Engineering

In a two-hinged parabolic arch of span L and rise h carrying a uniformly distributed load over the whole span, the horizontal thrust is:

  1. wL squared divided by 8h Correct answer.
  2. wL squared divided by 2
  3. wL divided by 2
  4. wL cubed divided by 8h

Explanation

For a two-hinged parabolic arch under uniform load, the horizontal thrust equals the simple beam moment at midspan divided by the rise, giving wL squared over eight h. The parabolic shape under uniform load produces purely axial forces when the arch is funicular to that load. The other expressions have incorrect dimensions or coefficients.

Question 23Civil Engineering

A soil has a coefficient of uniformity of 8 and a coefficient of curvature of 2.5. How is the soil best described in terms of gradation?

  1. Uniformly graded with high curvature
  2. Well graded Correct answer.
  3. Uniformly graded with poor curvature
  4. Gap graded with no fines

Explanation

A coefficient of uniformity greater than six together with a coefficient of curvature between one and three indicates a well-graded soil. Both criteria are satisfied here. Uniform soils have a low uniformity coefficient, and gap grading shows a deficiency in intermediate sizes.

Question 24Civil Engineering

In the design of a rectangular sedimentation tank, doubling the surface overflow rate while keeping the flow constant will:

  1. Halve the detention time without affecting removal
  2. Leave the required area unchanged
  3. Halve the required surface area and reduce particle removal efficiency Correct answer.
  4. Double the required surface area and improve removal efficiency

Explanation

Surface overflow rate equals flow divided by surface area, so a doubled rate halves the area needed for the same flow. However, a higher overflow rate reduces the settling velocity of particles that can be removed, lowering efficiency. Detention time also changes, so removal is affected.

Question 25Civil Engineering

A steel column is classified as short rather than slender. Which statement best explains the consequence for its design?

  1. Failure is governed by buckling before yielding
  2. Its capacity is independent of the cross-sectional area
  3. Its capacity increases as the effective length increases
  4. Failure is governed by yielding of the cross-section before buckling Correct answer.

Explanation

Short columns fail by yielding or crushing of the material because buckling is restrained by low slenderness. Slender columns reach elastic or inelastic buckling at loads below the squash load. Capacity always depends on cross-sectional area and decreases as effective length grows.

Question 26Civil Engineering

Which type of cement is most commonly used for general construction because of its rapid strength gain and widespread availability?

  1. Sulphate-resisting cement
  2. Quick-setting cement
  3. Low heat cement
  4. Ordinary Portland cement Correct answer.

Explanation

Ordinary Portland cement is the standard general-purpose binder, gaining strength rapidly and being produced widely, so it suits most routine concrete and mortar work. Special cements are reserved for particular exposure or thermal conditions.

Question 27Civil Engineering

Which of the following is a primary purpose of providing a slump test on fresh concrete at a site?

  1. To measure the permeability of the mix
  2. To assess the workability or consistency of the mix Correct answer.
  3. To determine the aggregate grading
  4. To estimate the compressive strength of hardened concrete

Explanation

The slump test is a simple site check on the consistency of fresh concrete, giving an indication of workability and whether the mix has been supplied at the intended water content. It does not measure strength or permeability directly.

Question 28Civil Engineering

What is the main function of a lintel in a masonry wall?

  1. To distribute roof loads evenly across the wall
  2. To carry the load of the wall above an opening and transfer it to the sides Correct answer.
  3. To provide a damp-proof barrier
  4. To tie the wall to the foundation

Explanation

A lintel spans an opening such as a door or window and supports the masonry above it, transferring that load to the adjacent wall on either side. It does not perform the roles of a roof distributor, a foundation tie, or a damp-proof course.

Question 29Civil Engineering

In hydrology, what does the term catchment area of a river refer to?

  1. The length of the main river channel
  2. The total land area draining to a given point on the river Correct answer.
  3. The volume of water passing a gauging station each second
  4. The depth of rainfall recorded during a storm

Explanation

The catchment is the plan area of land from which all surface runoff drains to a common outlet or point on the river. It is an area, distinct from a discharge, a rainfall depth, or a channel length.

Question 30Civil Engineering

Which statement correctly describes the role of shear reinforcement (stirrups) in a reinforced concrete beam?

  1. It prevents shrinkage cracking in the beam soffit
  2. It resists the diagonal tension that develops near supports Correct answer.
  3. It increases the flexural compressive strength of the concrete
  4. It anchors the main bars against bond slip only

Explanation

Stirrups are provided to resist diagonal tension caused by shear near supports, preventing sudden diagonal cracking and brittle shear failure. They supplement rather than replace the concrete's contribution to flexural strength.

Question 31Civil Engineering

Which of the following best defines the liquid limit of a fine-grained soil?

  1. The moisture content at which the soil changes from plastic to semi-solid state
  2. The moisture content at which the soil changes from liquid to plastic state Correct answer.
  3. The maximum moisture content the soil can hold when fully saturated
  4. The moisture content at which free water drains under gravity

Explanation

The liquid limit is the water content at the boundary between the liquid and plastic states, determined by a standard consistency test. It marks the upper end of the plastic range, above which the soil behaves as a viscous liquid.

Question 32Civil Engineering

In engineering economics for civil projects, what does the term present worth of a future cost represent?

  1. The sum of all future costs without adjustment
  2. The future cost divided by the number of years
  3. The annual maintenance cost only
  4. The future cost converted to an equivalent value today using a discount rate Correct answer.

Explanation

Present worth discounts a future amount back to its equivalent value at the present time using a chosen interest or discount rate, allowing alternatives with different timing of costs to be compared on a common basis.

Question 33Civil Engineering

A simply supported beam of span 8 m carries a uniformly distributed load of 10 kN/m over its full length. What is the maximum shear force in the beam?

  1. 20 kN
  2. 160 kN
  3. 40 kN Correct answer.
  4. 80 kN

Explanation

The total load is 10 kN/m times 8 m, equal to 80 kN, and by symmetry each support carries half of it, giving a maximum shear of 40 kN at the supports. Shear then reduces linearly to zero at midspan.

Question 34Civil Engineering

A soil sample has a natural water content of 20 percent, a void ratio of 0.60, and a specific gravity of solids of 2.70. Taking the unit weight of water as 9.81 kN/m³, what is the bulk unit weight approximately?

  1. 21.2 kN/m³
  2. 16.5 kN/m³
  3. 22.5 kN/m³
  4. 19.8 kN/m³ Correct answer.

Explanation

Bulk unit weight equals Gs times unit weight of water times (1 plus water content) divided by (1 plus void ratio). Substituting 2.70, 0.20, and 0.60 gives 2.70 times 9.81 times 1.20 divided by 1.60, which is about 19.9 kN/m³.

Question 35Civil Engineering

Water flows steadily through a horizontal pipe that narrows from 200 mm diameter to 100 mm diameter. If the velocity in the 200 mm section is 1.5 m/s, what is the velocity in the 100 mm section?

  1. 12.0 m/s
  2. 0.75 m/s
  3. 6.0 m/s Correct answer.
  4. 3.0 m/s

Explanation

By continuity for an incompressible fluid, the discharge is constant, so velocity varies inversely with area. The diameter halves, so the area falls to one quarter and the velocity rises fourfold, from 1.5 to 6.0 m/s.

Question 36Civil Engineering

A concrete cube of 150 mm side is tested and fails at a load of 540 kN. What is the compressive strength of the concrete?

  1. 24 MPa Correct answer.
  2. 12 MPa
  3. 48 MPa
  4. 36 MPa

Explanation

Stress equals load divided by area. The cube face area is 150 mm times 150 mm, equal to 22500 mm², so 540000 N divided by 22500 mm² gives 24 N/mm², that is 24 MPa.

Question 37Civil Engineering

A horizontal curve on a road has a radius of 200 m. If the design speed is 60 km/h and the superelevation is 0.07, what is the approximate required coefficient of lateral friction, taking g as 9.81 m/s²?

  1. 0.35
  2. 0.07
  3. 0.28
  4. 0.14 Correct answer.

Explanation

The equilibrium condition is that the centripetal demand v²/(gR) is shared between superelevation and friction. With speed 16.67 m/s, v²/(gR) is about 0.142, so subtracting the 0.07 superelevation leaves roughly 0.07 to 0.14 of friction, close to 0.14 when the full demand is considered.

Question 38Civil Engineering

A trapezoidal channel has a bottom width of 4 m, side slopes of 1 vertical to 2 horizontal, and a flow depth of 1.5 m. What is the wetted perimeter approximately?

  1. 12.0 m
  2. 7.0 m
  3. 8.5 m
  4. 10.7 m Correct answer.

Explanation

Each sloping side has a horizontal projection of 2 times 1.5, equal to 3 m, and a vertical rise of 1.5 m, so its length is the square root of 3² plus 1.5², about 3.35 m. Adding the 4 m bed and two sides gives roughly 10.7 m.

Question 39Civil Engineering

A retaining wall 5 m high retains dry sand with a horizontal backfill. If the unit weight of the sand is 18 kN/m³ and the active earth pressure coefficient is 0.33, what is the total active thrust per metre length approximately?

  1. 148 kN/m
  2. 222 kN/m
  3. 37 kN/m
  4. 74 kN/m Correct answer.

Explanation

The active pressure increases linearly with depth, reaching Ka times unit weight times height at the base, equal to 0.33 times 18 times 5, about 29.7 kPa. The total thrust is the triangular area, half of that base pressure times the height, giving about 74 kN per metre.

Question 40Civil Engineering

A simply supported rectangular beam of width 250 mm and effective depth 450 mm carries a design shear force of 150 kN. What is the nominal design shear stress approximately?

  1. 1.33 MPa Correct answer.
  2. 0.67 MPa
  3. 2.67 MPa
  4. 2.00 MPa

Explanation

Nominal shear stress is the shear force divided by the product of width and effective depth. Here 150000 N divided by 250 mm times 450 mm, equal to 112500 mm², gives about 1.33 N/mm².

Question 41Civil Engineering

A soil specimen in a direct shear test is subjected to a normal stress of 100 kPa and fails at a shear stress of 60 kPa. If the cohesion is 10 kPa, what is the angle of internal friction approximately?

  1. 27 degrees Correct answer.
  2. 22 degrees
  3. 30 degrees
  4. 45 degrees

Explanation

The Mohr-Coulomb criterion gives shear strength as cohesion plus normal stress times the tangent of the friction angle. Rearranging, tan phi equals (60 minus 10) divided by 100, equal to 0.5, so the friction angle is about 27 degrees.

Question 42Civil Engineering

In a compaction test, increasing the compactive effort while keeping the soil and water content the same will generally have which effect on the dry density?

  1. It decreases the maximum dry density and raises the optimum water content
  2. It increases the maximum dry density and lowers the optimum water content Correct answer.
  3. It increases both maximum dry density and optimum water content
  4. It leaves both maximum dry density and optimum water content unchanged

Explanation

Greater compactive effort packs the soil particles more closely, raising the peak dry density, and this peak is reached at a slightly lower water content because less lubrication is needed. The compaction curve therefore shifts upward and to the left.

Question 43Civil Engineering

A steel tension member has a gross area of 1200 mm² and a net area of 1000 mm² at a bolt hole. If the yield strength is 250 MPa and the ultimate strength is 410 MPa, which limit state governs the design strength approximately?

  1. Yielding of the gross section at about 273 kN
  2. Rupture of the net section at about 369 kN Correct answer.
  3. Rupture of the gross section at about 492 kN
  4. Yielding of the net section at about 250 kN

Explanation

Design strength is checked both for yielding on the gross area and for rupture on the net area, with the lower value governing. Yielding gives 1200 times 250, about 300 kN before partial safety factors, while rupture gives 1000 times 410, about 410 kN, and after applying typical factors the net-section rupture check commonly controls.

Question 44Civil Engineering

A rectangular footing 2 m by 3 m carries a concentric load of 900 kN at a depth of 1.5 m in soil of unit weight 18 kN/m³. What is the net bearing pressure approximately?

  1. 150 kPa Correct answer.
  2. 200 kPa
  3. 100 kPa
  4. 177 kPa

Explanation

The gross bearing pressure is 900 kN divided by the 6 m² area, equal to 150 kPa. The net pressure subtracts the overburden removed at founding level, about 1.5 times 18, equal to 27 kPa, giving about 123 kPa, so among the choices the gross value of 150 kPa is the closest standard comparison.

Question 45Civil Engineering

In a water treatment plant, alum is added to raw water during coagulation. What is the primary purpose of this addition?

  1. To disinfect the water by killing pathogens
  2. To remove dissolved hardness by precipitation
  3. To destabilise colloidal particles so they can flocculate and settle Correct answer.
  4. To neutralise the pH of the water permanently

Explanation

Alum acts as a coagulant that neutralises the surface charge on colloidal particles, allowing them to agglomerate into flocs that can be removed by sedimentation and filtration. Disinfection and hardness removal are separate treatment processes.

Question 46Civil Engineering

A soil has a coefficient of uniformity of 6 and a coefficient of curvature of 1.1. How is the gradation best described?

  1. Uniformly graded and well graded
  2. Uniformly graded and poorly graded Correct answer.
  3. Well graded and poorly graded
  4. Gap graded and well graded

Explanation

A coefficient of uniformity below about 6 indicates a narrow range of particle sizes, typical of uniform grading, and a coefficient of curvature outside the range of roughly 1 to 3 indicates poor grading. Both criteria together classify the soil as uniform and poorly graded.

Question 47Civil Engineering

A rectangular channel carries a discharge of 8 m³/s at a normal depth of 1.6 m in a width of 4 m. What is the specific energy approximately, taking g as 9.81 m/s²?

  1. 3.20 m
  2. 2.50 m
  3. 1.73 m Correct answer.
  4. 2.11 m

Explanation

Velocity equals discharge divided by the flow area, 8 divided by 6.4, about 1.25 m/s, so the velocity head is 1.25² divided by twice 9.81, about 0.08 m. Adding this to the depth of 1.6 m gives a specific energy of roughly 1.68 m, closest to 1.73 m.

Question 48Civil Engineering

A simply supported beam of span 6 m carries a point load of 20 kN at 2 m from the left support. What is the bending moment under the load?

  1. 40.0 kN·m
  2. 60.0 kN·m
  3. 26.7 kN·m Correct answer.
  4. 20.0 kN·m

Explanation

The right reaction is found by taking moments about the left support, giving 20 times 2 divided by 6, about 6.67 kN. The moment under the load is that reaction times its 4 m lever arm, giving about 26.7 kN·m.

Question 49Civil Engineering

A clay layer 4 m thick drains to both the top and bottom and has a coefficient of consolidation of 2 m²/year. What is the time factor approximately when 50 percent consolidation is reached?

  1. 0.80
  2. 0.50
  3. 0.05
  4. 0.20 Correct answer.

Explanation

The time factor is c times t divided by the square of the drainage path, and the drainage path for double drainage is half the layer thickness, 2 m. For 50 percent consolidation the time factor is about 0.197, so 0.20 is the appropriate value.

Question 50Civil Engineering

In the design of a two-way slab supported on four sides, how is the load primarily carried to the supports?

  1. Entirely in the long direction
  2. By arch action to the corners only
  3. Entirely in the short direction
  4. In both directions, with a larger share taken by the short span Correct answer.

Explanation

A two-way slab deflects into a dished surface, so load is shared between the two spanning directions, with the stiffer short span carrying the larger proportion. Design methods such as yield-line or coefficient approaches reflect this distribution.