Theory of Structures MCQ Questions and Answers in Civil Engineering

Question.  A short column (30 cm × 20 cm) carries a load P₁ at 4 cm on one side and another load P₂ at 8 cm on the other side along a principal section parallel to longer dimension. If the extreme intensity on either side is same, the ratio of P₁ to P₂ will be
(a) 2/3
(b) 3/2
(c) 8/5
(d) 5/8

Answer : C

Question. Principal planes are subjected to
(a) Normal stresses only
(b) Tangential stresses only
(c) Normal stresses as well as tangential stresses
(d) None of these

Answer : A

Question. The ratio of the length and depth of a simply supported rectangular beam which experiences maximum bending stress equal to tensile stress, due to same load at its mid span, is
(a) 1/2
(b) 2/3
(c) 1/4
(d) 1/3

Answer : B

Question. Slenderness ratio of a long column, is
(a) Area of cross-section divided by radius of gyration
(b) Area of cross-section divided by least radius of gyration
(c) Radius of gyration divided by area of cross-section
(d) Length of column divided by least radius of gyration

Answer : D

Question. The ratio of lateral strain to axial strain of a homogeneous material, is known
(a) Yield ratio
(b) Hooke’s ratio
(c) Poisson’s ratio
(d) Plastic ratio

Answer : C

Question. The ratio of the length and diameter of a simply supported uniform circular beam which experiences maximum bending stress equal to tensile stress due to same load at its mid span, is
(a) 1/8
(b) 1/4
(c) 1/2
(d) 1/3

Answer : C

Question. For beams breadth is constant,
(a) Depth d ∝ M
(b) Depth d ∝ √M
(c) Depth d ∝ 3√M
(d) Depth d ∝ 1/MM

Answer : B

Question.  A compound truss may be formed by connecting two simple rigid frames, by
(a) Two bars
(b) Three bars
(c) Three parallel bars
(d) Three bars intersecting at a point

Answer : B

Question. A shaft is subjected to bending moment M and a torque T simultaneously. The ratio of the maximum bending stress to maximum shear stress developed in the shaft, is
(a) M/T
(b) T/M
(c) 2M/T
(d) 2T/M

Answer : C

Question. Flat spiral springs
(a) Consist of uniform thin strips
(b) Are supported at outer end
(c) Are wound by applying a torque
(d) All the above

Answer : D

Question. A cantilever of length ‘L’ is subjected to a bending moment ‘M’ at its free en(d) If EI is the flexural rigidity of the section, the deflection of the free end, is
(a) ML/EI
(b) ML/2EI
(c) ML2/2EI
(d) ML2/3EI

Answer : D

Question. The ratio of the maximum deflections of a simply supported beam with a central load W and of a cantilever of same length and with a load W at its free end, is
(a) 1/8
(b) 1/10
(c) 1/12
(d) 1/16

Answer : D

Question. A close coil helical spring when subjected to a moment M having its axis along the axis of the helix
(a) It is subjected to pure bending
(b) Its mean diameter will decrease
(c) Its number of coils will increase
(d) All the above

Answer : A

Question. The maximum magnitude of shear stress due to shear force F on a rectangular section of area A at the neutral axis, is
(a) F/A
(b) F/2A
(c) 3F/2A
(d) 2F/3A

Answer : C

Question. A cantilever of length 2 cm and depth 10 cm tapers in plan from a width 24 cm to zero at its free en(d) If the modulus of elasticity of the material is 0.2 × 106 N/mm2, the deflection of the free end, is
(a) 2 mm
(b) 3 mm
(c) 4 mm
(d) 5 mm

Answer : D

Question. A three hinged arch is generally hinged at its supports and
(a) At one quarter span
(b) At the crown
(c) Anywhere in the rib
(d) None of these

Answer : B

Question. A masonry dam (density = 20,000 N/m³) 6 m high, one metre wide at the top and 4 m wide at the base, has vertical water face. The minimum stress at the base of the dam when the reservoir is full, will be
(a) 75 N/m²
(b) 750 N/m²
(c) 7,500 N/m²
(d) 75,000 N/m²

Answer : C

Question. In the truss, the force in the member AC is
(a) 6.25 t compressive
(b) 8.75 t tensile
(c) t tensile
(d) t compressive

Answer : D

Question. A simply supported rolled steel joist 8 m long carries a uniformly distributed load over it span so that the maximum bending stress is 75 N/mm2. If the slope at the ends is 0.005 radian and the value of E = 0.2 × 106 N/mm², the depth of the joist, is
(a) 200 mm
(b) 250 mm
(c) 300 mm
(d) 400 mm

Answer : D

Question. A steel rod of sectional area 250 sq. mm connects two parallel walls 5 m apart. The nuts at the ends were tightened when the rod was heated to 100°(c) If α_steel = 0.000012/C°, E_steel = 0.2 MN/mm², the tensile force developed at a temperature of 50°C, is
(a) 80 N/mm²
(b) 100 N/mm²
(c) 120 N/mm²
(d) 150 N/mm²

Answer : C

Question. A truss containing j joints and m members, will be a simple truss if
(a) m = 2j - 3
(b) j = 2m - 3
(c) m = 3j - 2
(d) j = 3m - 2

Answer : A

Question. If a concrete column 200 × 200 mm in cross-section is reinforced with four steel bars of 1200 mm² total cross-sectional are(a) Calculate the safe load for the column if permissible stress in concrete is 5 N/mm² and E_s is 15 E_c
(a) 264 MN
(b) 274 MN
(c) 284 MN
(d) 294 MN

Answer : C

Question. Gradually applied static loads do not change with time their
(a) Magnitude
(b) Direction
(c) Point of application
(d) All the above

Answer : D

Question. A steel bar 20 mm in diameter simply-supported at its ends over a total span of 40 cm carries a load at its centre. If the maximum stress induced in the bar is limited to N/mm2, the bending strain energy stored in the bar, is
(a) 411 N mm
(b) 511 N mm
(c) 611 N mm
(d) 711 N mm

Answer : C

Question. In plastic analysis, the shape factor for rectangular section, is
(a) 1.4
(b) 1.5
(c) 1.6
(d) 1.7

Answer : B

Question. The equivalent length is of a column of length L, having both the ends fixed, is
(a) 2L
(b) L
(c) L/2
(d) L/√2

Answer : C

Question. The maximum deflection due to a load W at the free end of a cantilever of length L and having flexural rigidity EI, is
(a) WL²/2EI
(b) WL²/3EI
(c) WL³/2EI
(d) WL³/3EI

Answer : D

Question. Pick up the correct statement from the following:
(a) The structural member subjected to compression and whose dimensions are small as compared to its length, is called a stmt
(b) The vertical compression members are generally known as columns or stanchions
(c) Deflection in lateral direction of a long column, is generally known as buckling
(d) All the above

Answer : D

Question. Stress may be defined as
(a) Force per unit length
(b) Force per unit volume
(c) Force per unit area
(d) None of these

Answer : C

Question. If Q is load factor, S is shape factor and F is factor of safety in elastic design, the following:
(a) Q = S + F
(b) Q = S - F
(c) Q = F - S
(d) Q = S × F

Answer : D

Question. The yield moment of a cross section is defined as the moment that will just produce the yield stress in
(a) The outer most fibre of the section
(b) The inner most fibre of the section
(c) The neutral fibre of the section
(d) The fibre everywhere

Answer : A

Question. A load of 1960 N is raised at the end of a steel wire. The minimum diameter of the wire so that stress in the wire does not exceed 100 N/mm2 is:
(a) 4.0 mm
(b) 4.5 mm
(c) 5.0 mm
(d) 5.5 mm

Answer : C

Question. A simply supported beam which carries a uniformly distributed load has two equal overhangs. To have maximum (b)M. produced in the beam least possible, the ratio of the length of the overhang to the total length of the beam, is
(a) 0.207
(b) 0.307
(c) 0.407
(d) 0.508

Answer : A

Question. A two hinged parabolic arch of span l and rise h carries a load varying from zero at the left end to ω per unit run at the right en(d) The horizontal thrust is
(a) ωl2/4h
(b) ωl2/8h
(c) ωl2/12h
(d) ωl2/16h

Answer : D

Question. For determining the support reactions at A and B of a three hinged arch, points B and Care joined and produced to intersect the load line at D and a line parallel to the load line through A at D’. Distances AD, DD’ and AD’ when measured were 4 cm, 3 cm and 5 cm respectively. The angle between the reactions at A and B is
(a) 30°
(b) 45°
(c) 60°
(d) 90°

Answer : D

Question. A steel bar 5 m × 50 mm is loaded with 2,50,000 N. If the modulus of elasticity of the material is 0.2 MN/mm² and Poisson’s ratio is 0.25, the change in the volume of the bar is:
(a) 1.125 cm³
(b) 2.125 cm³
(c) 3.125 cm³
(d) 4.125 cm²

Answer : C

Question. Beams composed of more than one material, rigidly connected together so as to behave as one piece, are known as
(a) Compound beams
(b) Indeterminate beams
(c) Determinate beams
(d) Composite beams

Answer : D

Question. A material is said to be perfectly elastic if
(a) It regains its original shape on removal of the load
(b) It regains its original shape partially on removal of the load
(c) It does not regain its original shape at all
(d) None of these

Answer : A

Question. A simply supported uniform rectangular bar breadth b, depth d and length L carries an isolated load W at its mid-span. The same bar experiences an extension e under same tensile loa(d) The ratio of the maximum deflection to the elongation, is
(a) L/d
(b) L/2d
(c) (L/2d)²
(d) (L/3d)²

Answer : C

Question. A body is said to be in equilibrium if
(a) It moves horizontally
(b) It moves vertically
(c) It rotates about its (c)G.
(d) None of these

Answer : D

Question. At any point of a beam, the section modulus may be obtained by dividing the moment of inertia of the section by
(a) Depth of the section
(b) Depth of the neutral axis
(c) Maximum tensile stress at the section
(d) Maximum compressive stress at the section

Answer : B

Question. The ratio of circumferential stress to the longitudinal stress in the walls of a cylindrical shell, due to flowing liquid, is
(a) 1/2
(b) 1
(c) 1(1/2)
(d) 2

Answer : D

Question. At yield point of a test piece, the material
(a) Obeys Hooke’s law
(b) Behaves in an elastic manner
(c) Regains its original shape on removal of the load
(d) Undergoes plastic deformation

Answer : D

Question. Pick up the correct statement from the following:
(a) The moment of inertia is calculated about the axis about which bending takes place
(b) If tensile stress is less than axial stress, the section experiences compressive stress
(c) If tensile stress is equal to axial stress, the section experiences compressive stress
(d) All the above

Answer : D

Question. Pick up the correct statement from the following:
(a) In a loaded beam, the moment at which the first yield occurs is called yield moment
(b) In a loaded beam, the moment at which the entire section of the beam becomes fully plastic, is called plastic moment
(c) In a fully plastic stage of the beam, the neutral axis divides the section in two sections of equal area
(d) All the above

Answer : D

Question. If a three hinged parabolic arch, (span l, rise h) is carrying a uniformly distributed load w/unit length over the entire span,
(a) Horizontal thrust is wl²/8h
(b) S.F. will be zero throughout
(c) (b)M. will be zero throughout
(d) All the above

Answer : D

Question. Y are the bending moment, moment of inertia, radius of curvature, modulus of If M, I, R, E, F and elasticity stress and the depth of the neutral axis at section, then
(a) MI = RE = FY
(b) IM = RE = FY
(c) MI = ER = FY
(d) MI = ER = YF

Answer : C

Question. The deflection of a uniform circular bar of diameter d and length l, which extends by an amount under a tensile pull W, when it carries the same load at its mid-span, is
(a) el/2d
(b) e²l/3d²
(c) el²/3d²
(d)e1²/3d²

Answer : C

Question. The ratio of the area of cross-section of a circular section to the area of its core, is
(a) 4
(b) 8
(c) 12
(d) 16

Answer : D

Question. Shear strain energy theory for the failure of a material at elastic limit, is due to
(a) Rankine
(b) Guest or Trecas
(c) St. Venant
(d) Von Mises

Answer : D

Question. A simply supported beam A carries a point load at its mid span. Another identical beam B carries the same load but uniformly distributed over the entire span. The ratio of the maximum deflections of the beams A and B, will be
(a) 2/3
(b) 3/2
(c) 5/8
(d) 8/5

Answer : D

Question. The stiffness of the close coil helical spring is
(a) d4N/8D
(b) d4N/4D3n
(c) 4D3N/d4n
(d) 8D3N/d4n

Answer : A

Question. The eccentricity (e) of a hollow circular column, external diameter 25 cm, internal diameter 15 cm for an eccentric load 100 t for non-development of tension, is
(a) 2.75 cm
(b) 3.00 cm
(c) 3.50 cm
(d) 4.25 cm

Answer : D

Question. The ratio of the stresses produced by a suddenly applied load and by a gradually applied load on a bar, is
(a) 1/4
(b) 1/2
(c) 1
(d) 2

Answer : D

Question. The locus of the end point of the resultant of the normal and tangential components of the stress on an inclined plane, is
(a) Circle
(b) Parabola
(c) Ellipse
(d) Straight line

Answer : C

Question. The load on a spring per unit deflection, is called
(a) Stiffness
(b) Proof resilience
(c) Proof stress
(d) Proof load

Answer : A

Question. In plastic analysis, the shape factor for a triangular section, is
(a) 1.5
(b) 1.34
(c) 2.34
(d) 2.5

Answer : C

Question. Maximum strain theory for the failure of a material at the elastic limit, is known as
(a) Guest's or Trecas' theory
(b) St. Venant's theory
(c) Rankine's theory
(d) Haig's theory

Answer : B

Question. In case of a simply supported rectangular beam of span L and loaded with a central load W, the length of elasto-plastic zone of the plastic hinge, is
(a) L/2
(b) L/3
(c) L/4
(d) L/5

Answer : B

Question. Pick up the correct statement from the following:
(a) For a uniformly distributed load, the shear force varies linearly
(b) For a uniformly distributed load, (b)M. curve is a parabola
(c) For a load varying linearly, the shear force curve is a parabola
(d) All the above

Answer : D

Question. For beams of uniform strength, if depth is constant,
(a) Width b ∝ M
(b) Width b ∝ √M
(c) Width b ∝ 3√M
(d) Width b ∝ 1/M

Answer : A

Question. The ratio of the section modulus of a square section of side B and that of a circular section of diameter D, is
(a) 2π/15
(b) 3π/16
(c) 3π/8
(d) π1/6

Answer : B

Question. A square column carries a load P at the centroid of one of the quarters of the square. If a is the side of the main square, the combined bending stress will be
(a) P/a²
(b) 2P/a²
(c) 3P/a²
(d) 4P/a²

Answer : C

Question. A bar L metre long and having its area of cross-section A, is subjected to a gradually applied tensile load W. The strain energy stored in the bar is
(a) WL/2AE
(b) WL/AE
(c) W2/LAE
(d) W2/L2AE

Answer : D

Question. A composite beam is composed of two equal strips one of brass and other of steel. If the temperature is raised
(a) Steel experiences tensile force
(b) Brass experiences compressive force
(c) Composite beam gets subjected to a couple
(d) All the above

Answer : D

Question. The ratio of moments of inertia of a triangular section about its base and about a centroidal axis parallel to its base, is
(a) 1.0
(b) 1.5
(c) 2.0
(d) 3.0

Answer : D

Question. In case of a simply supported I-section beam of span L and loaded with a central load W, the length of elasto-plastic zone of the plastic hinge, is
(a) L/2
(b) L/3
(c) L/4
(d) L/5

Answer : D

Question. The ratio of maximum and average shear stresses on a rectangular section, is
(a) 1
(b) 1.25
(c) 1.5
(d) 2.5

Answer : C

Question. A rolled steel joist is simply supported at its ends and carries a uniformly distributed load which causes a maximum deflection of 10 mm and slope at the ends of 0.002 radian. The length of the joist will be,
(a) 10 m
(b) 12 m
(c) 14 m
(d) 16 m

Answer : D

Question. Inertia of a rectangular section of width and depth about an axis passing the moment of through (c)G. and parallel to its width is
(a) BD²/6
(b) BD³/6
(c) BD³/12
(d) B²D/6

Answer : C