Quiz: Civil Engineering

Exam: DFCCIL EXECUTIVE

Topic: STRUCTURE ANALYSIS

Each question carries 1 mark

Negative marking: 1/4 mark

Time: 10 Minutes

Q1. Maxwell’s reciprocal theorem in structural analysis

(a) is true for any structure obeying hook’s law

(b) can be applied to the rotations caused by flexure, shear or torsion

(c) is useful in analyzing indeterminate structure

(d) all of these

Q2. For the plane frame as shown in the figure, the degree of kinematic indeterminacy neglecting axial deformation,

(a) 3

(b) 5

(c) 7

(d) 9

Q3. The conditions required to be satisfied for the analysis of indeterminate structure are-

(a) Equilibrium

(b) compatibility

(c) Force-displacement

(d) all of these

Q4. The total strain energy of a beam of length L, having moment of inertia of its section I, when subjected to a bending moment M is

(a) (M^2/EI)^* δx

(b) ∫(M^2/2EI)^* δx

(c) ∫_0^L▒〖(M^2/2EI)^* δx〗

(d) None of these

Q5. Which method not fall under the category of displacement method?

(a) Moment distribution method

(b) Slope deflection method

(c) Method of consistent deformation

(d) Kani’s method

Q7. What does the influence line for Bending moment indicate?

Bending moment at any section on the structure for a given oppositions of load.

Bending moment at a given section for any position of a point load.

(a) Only A

(b) Only B

(c) Both A and B

(d) Neither A nor B

Q8. Influence line diagrams can be drawn for

(a) only beams

(b) Beams arches, trusses etc.

(c) Only arches

(d) Only trusses

Q9. The maximum bending moment in a beam under a wheel load caused by a train of moving load is

(a) when this wheel and the C.G. of the total system are equidistant from the supports of the beam.

(b) always at the center

(c) closet to CG of loads

(d) None of above

Q10. A single load of 100 kN rolls along a girder of 20 m simply supported span, the maximum bending moment is –

(a) 100 kNm

(b) 500 kNm

(c) 150 kNm

(d) 600 kNm

L1Difficulty 5

QTags Civil

QCereator Anubhav Gupta

SOLUTION

S1. Ans.(d)

Sol. Maxwell’s reciprocal theorem in structural analysis is true for any structure obeying Hook’s law and is useful in analyzing indeterminate structure and can be applied to the rotations caused by flexure, shear or torsion.

S2. Ans.(b)

Sol. Joints (J) = 4

External Reactions (r_e)=5

Members (m) = 3

Internal hinged reaction (r_r) = 1

Degree of kinematic indeterminacy (D_k) = ?

D_K=3j-r_e-m+r_r

=(3×4)-5-3+1

▭(D_K=5 )

S3. Ans.(d)

Sol. The condition required to be satisfied for the analysis of indeterminate structure are equilibrium, compatibility and force-displacement relationship.

S4. Ans.(c)

Sol. Strain energy stored due to axial load (W) is given by-

▭(u= ∫_0^L▒(W^2 dx)/2EI)

Strain energy stored due to bending moment (M) is given by-

▭(U= ∫_0^L▒(M^2 dx)/(2EI ))

dx = elemental length

EI = flexural rigidity

L = length of beam

S5. Ans.(c)

Sol. Method comes under displacement methods are-

→ slope deflection method

→ moment distribution method

→ Kani’s method

→ Minimum potential energy method.

S6. Ans.(a)

Sol. The number of plastic hinges is one more than the order of statically indeterminacy which will cause the overall total collapse of a structure.

S7. Ans.(b)

Sol. The influence line for bending moment indicates bending moment at a given section for any position of a point load.

S8. Ans.(b)

Sol. The influence line diagram is the graphical representation for reaction, shear force and bending moment due to moving load. It can be drawn for beams, arches, trusses etc.

S9. Ans.(a)

Sol. The maximum bending moment in a beam under a wheel load caused by a train of moving load is when this wheel and the C.G. of the total system are equidistant from the supports of the beam.

S10. Ans.(b)

Sol. The maximum bending moment due to moving load on a simply supported beam occurs under the load and it will be maximum at mid span, hence

Maximum bending moment 〖(M〗_(max)) = wl/4.

Given W=100 kN ,l=20 m

M_max=(100×20)/4

▭(M_max=500 kN-m)