SSC-JUNIOR ENGINEER (Civil & Structural) Online Exam 2016 (Part-II)

Total Questions: 50

41. The influence lines for any stress function are used for obtaining the maximum value due to __________.

Correct Answer: D. All options are correct
Solution:No explanation given in the book

42. Bolts are most suitable to carry ________.

Correct Answer: C. axial tension
Solution:Bolted joints are one of the most common elements in construction and machine design. They consist of fasteners that capture and join other parts, and are secured with the mating of screw threads.

There are two main types of bolted joint designs: tension joints and shear joints.

In the tension joint, the bolt and clamped components of the joint are designed to transfer an applied tension load through the joint by way of the clamped components by the design of a proper balance of joint and bolt stiffness.

The second type of bolted joint transfers the applied load in shear of the bolt shank and relies on the shear strength of the bolt. Tension loads on such a joint are only incidental.

43. The ratio of the stresses produced by suddenly applied and gradually applied loades on a bar is __________.

Correct Answer: D. 2
Solution:Gradually Applied Load

When a load is applied in instalments, i.e., load of 100 N to be applied. First a load of 5 N, then 10 N, 15 N 20 N ------100 N is applied.

Overall it causes less stress and less strain as compared to suddenly applied load.

Suddenly Applied Load

When the total force is applied in one instalment, i.e., force of 100 N is applied in one instalment. It causes 2 times the stress as compared to when the same load is applied gradually.

The ratio of the stresses produced by suddenly applied and gradually applied loads on a bar is 0.25.

44. Maximum allowable shear stress in a section is 100 kg/cm². If the bar is subjected to tensile force of 5000 kg and if the section is square shaped, what will be the dimension of sides of the squares?

Correct Answer: B. 5 cm
Solution:No explanation given in the book

45. Most efficient and economical section used as a beam is _________.

Correct Answer: A. I - section
Solution:I-Section is preferred to rectangular section for resisting Bending Moment (BM) because, in I-Section more than 80% of the bending moment is resisted by the flanges itself!

I-Section has higher moment of resistance (MoR) because the areas of flanges is away from the neutral axis (N.A.).

In a beam of I-Section, more material is positioned near the outer fibres representing the regions of greatest stress and hence is stronger than a beam of rectangular cross section.

46. A T-beam behaves as a rectangular beam of width equal to its flange if its neutral axis _________.

Correct Answer: C. remains within the flange
Solution:A T-beam, used in construction, is a load-bearing structure of reinforced concrete, wood or metal, with a t-shaped cross section. The top of the t-shaped cross section serves as a flange or compression member in resisting compressive stresses.

The web (vertical section) of the beam below the compression flange serves to resist shear stress and to provide greater separation for the coupled forces of bending. A T-beam behaves as a rectangular beam of width equal to its flange if its neutral axis remains within the flange. The T-beam has a big disadvantage compared to an I-beam because it has no bottom flange with which to deal with tensile forces.

47. A column has effective length L when its both ends are fixed. What will be the new effective length if one end becomes hinged?

Correct Answer: C. 1.41 L
Solution:No explanation given in the book

48. For a standard 45° fillet, the ratio of size of fillet to throat thickness is ________.

Correct Answer: C. √2 : 1
Solution:No explanation given in the book

49. Centre to centre distance of adjacent rivet or bolt holes measured in the direction of stress is called ________.

Correct Answer: B. Pitch
Solution:Pitch: The distance between centres of any two adjacent rivets is called the pitch.

Diagonal pitch: The distance between centres of any two adjacent rivets in the diagonal direction is called diagonal pitch.

Staggered pitch: The distance between any two consecutive rivets in a zig-zag riveting, measured parallel to the direction of stress in the member is called staggered pitch.

50. A simply supported beam of span L and flexural rigidity El, carries a unit point load at its centre. The strain energy in the beam due to bending is __________.

Correct Answer: C. L³/96EI
Solution:If I is the span and El the Flexural Rigidity, then for a uniformly distributed load w, the
end reactions are 1/2 and at a distance x from one end.

Using Equation (6),