SUB: STRUCTURAL ANALYSIS
MODULE-31C
MODULE- 31C Influence lines for determinate and indeterminate structures. ___________________________________________________________________________ 1.
Muller Breslau principle in structural analysis is used for (a) (b) (c) (d)
drawing influence line diagram for any force function writing virtual work equation super-position of load effects none of these
Ans: (a) 2.
A beam PQRS is 18m long and is simply supported at points Q and R 10m. Overhangs PQ and RS are 3m and 10m part. Overhangs PQ and RS are 3m and 5m respectively. A train of two point loads of 150 kN and 100 kN, 5m apart, crosses this beam from left to right with 100 kM load leading. The maximum sagging moment under the 150 kN load anywhere is (a) 500 kNm (b) 45kNm (c) 400 kNm (d) 375 kNm Ans:
360+40
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SUB: STRUCTURAL ANALYSIS MODULE-31C 3.
A beam PQRS is 18m long and is simply supported at points Q and R 10m. Overhangs PQ and RS are 3m and 10m part. Overhangs PQ and RS are 3m and 5m respectively. A train of two point loads of 150 kN and 100 kN, 5m apart, crosses this beam from left to right with 100 kM load leading. During the passage of the loads, the maximum and the minimum reactions at support R, in kN, are respectively (a) 300 and -30 (b) 300 and -25 (c) 225 and -30 (d) 225 and -25 Ans:
4.
A beam PQRS is 18m long and is simply supported at points Q and R 10m. Overhangs PQ and RS are 3m and 10m part. Overhangs PQ and RS are 3m and 5m respectively. A train of two point loads of 150 kN and 100 kN, 5m apart, crosses this beam from left to right with 100 kM load leading. The maximum hogging moment in the beam anywhere is (a) 300 kNm (b) 450 kNm (c) 500 kNm (d) 750 kNm Ans:
ILD for B.M at R
5.
Consider the beam ABCD and the influence line as shown below. The influence the pertains to
(a) Reaction at A, RA (b) Shear force at B, VB (c) Shear force on the left of C, (d) Shear force on the right of C, Ans: (b)
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SUB: STRUCTURAL ANALYSIS MODULE-31C 6.
The influence line diagram (ILD) shown is for the member
(a) PS (b) RS (c) PQ (d) QS Ans: (a) 7.
The span(s) to be loaded uniformly for maximum positive (upward) reaction at support P, as shown in the figure below, is (are)
(A) (C)
PQ only (B) QR and RS (D)
PQ and QR PQ and RS
Ans:
PQ and RS 8.
The given figure shows a portal truss:
The influence line for force in member BC will be
Ans: (c)
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SUB: STRUCTURAL ANALYSIS MODULE-31C 9.
For the fixed beam shown in the figure, the influence line diagram for the bending moment at the mid-span of the beam is best represented as
Ans: (a) 10. For the continuous beam shown in figure, the influence line diagram for support reaction at D is best represented as
Ans: (c) 11. Assertion(A): whether it is maximum BM at a section or absolute maximum BM, the moving UDL should cover the entire span of a simple beam if span is less than load length. Reason (R): whether it is maximum BM at a section or absolute maximum BM, the section in should be divided by the section in the same ratio in which the section divides the span, if the span is greater than load length. a) Both A and R are true and R is the correct explanation of A Both A and R is true but R is not a correct explanation of A A is true but R is false A is false but R is true Ans: (a)
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SUB: STRUCTURAL ANALYSIS MODULE-31C 12. The influence line
for the beam shown in figure-I will be as in
Ans: (b)
13. For beam shown in figure-I, an influence line diagram is shown in figure-II. The refers to
a) b) c) d)
Reaction Shear force at support D BM at support B Shear force at section XX
Ans: (d)
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SUB: STRUCTURAL ANALYSIS MODULE-31C 14. Match list-I (beam) with list-II (influence line for BM) and select the correct answer using the codes given below the lists:
Codes: a) b) c) d) Ans: (a)
A 2 3 2 1
B 1 1 5 3
C 3 4 3 5
D 5 5 4 4
15. The given figure shown a beam with its influence line for shear force and bending moment at section ‘l’:
The value of the shear force and bending moment at section ‘1’ due to a concentrated load of 20kN placed at mid-span will be a) 0.75 kN and 2.25 kN-m b) 5 kN and 5 kN-m c) 7.5 kN and 10 kN-m d) 10 kN and 30 kN-m Ans:
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SUB: STRUCTURAL ANALYSIS MODULE-31C 16. A beam with cantilevered ends is shown in the given figure. Which one of the following diagrams represent the influence line diagram for shear force at section just to the right of the support A?
Ans: (a) 17. The influence line diagram for reaction B of the beam shown in figure-I is
Ans: (d)
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SUB: STRUCTURAL ANALYSIS MODULE-31C 18. An applied couple ‘M’ is moving on a simply supported beam of span L as shown in given figure. The absolute maximum bending moment developed in the beam is
a)
M/2
b) M
c) 3M/2
d) 2M
Ans: (b) 19. For the propped cantilever shown in the figure, influence line for reaction at the propped end is given by = f(X).
The influence line ordinate ( equation a) = f(X).L b) = f(X).X c) = X - f(X).X d) = X - f(X).L
) for moment at A is given by the
Ans: (d) 20. Which one of the following diagrams represents the influence line for force in the member DG?
Ans: (d)
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SUB: STRUCTURAL ANALYSIS MODULE-31C 21. Which one of the following statements is correct? The influence line diagram (ILD) for bending moment at a section in a cantilever is a triangle extending between the section and the a) Fixed end with maximum ordinate under the section b) Fixed end with maximum ordinate under the end c) Unsupported end with maximum ordinate at the section d) Unsupported end with maximum ordinate at the unsupported end Ans: (d) 22. Which one of the following is correct in respect of the influence line for the bending moment at one-fourths of the span from left support of a prismatic beam simply support of a prismatic beam simply supported at ends? a) It is composed of straight lines only b) It is composed of curved lines only c) It is composed of straight and curved lines d) It is parabolic Ans: (a) 23. What is the shape of influence line diagram for the maximum bending moment in respect of a simply supported beam? a) Rectangular b) Triangular c) Parabolic d) Circular Ans: (c) 24. Consider the following statements: 1. Muller-Breslau,s principle is applicable only to indeterminate structures. 2. Muller-Breslau,s principle is applicable only to determinate structures. 3. Muller-Breslau,s principle is applicable only to determinate and indeterminate structures. 4. For two span continuos beam ABC, the influence line diagrams is/are (I)
(II)
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SUB: STRUCTURAL ANALYSIS MODULE-31C
Which of these statements are correct a) 1 and 4 (ii) b) 3 and (i) c) 2 and 4(i)
d) 3 and 4(ii)
Ans: (d)
25. Which one of the following diagrams corresponds to the influence line diagram for moment at A of the beam shown below in the figure?
Ans: (a) 26. What is the variation of influence line for stress function in statically determinate structure? a) b) c) d)
Parabolic Bilinear Linear Uniformly rectangular
Ans: (c)
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SUB: STRUCTURAL ANALYSIS MODULE-31C 27. A concentrated load W moves on the span of a three-hinged arch. The horizontal thrust at the supports is maximum when the load is at which one of the following? a) b) c) d)
The springing One-sixth of the span from one end Quarter span The crown
Ans: (d) 28. What is the ordinate of influence line at B for reaction below?
a)
0.5
b) 0.4c) 0.2
in figure
d)Zero
Ans: (a)
29. What is the area of influence line diagram for the reaction at the hinged end of a uniform propped cantilever beam of span L? a)
L/8
b)L/2 c) L/4
d) 3L/8
Ans:
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SUB: STRUCTURAL ANALYSIS MODULE-31C 30. What is the maximum ordinate for influence line for the force in the member marked X?
a)
1.0
b)1.33
c)1.50
d) 2.50
Ans: (b) 31. The influence line force in member BC is
Ans: (d)
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SUB: STRUCTURAL ANALYSIS MODULE-31C 32. The influence line diagram for the support moment at A of the fixed beam AB of constant EI is
Ans: (a)
33. The absolute maximum bending moment that a simply supported girder of span 10 m experiences when two concentrated loads 20 kN and 30 kN spaced 2 m apart (30 kN as leading at the right) crosses the girder from left to right, is a) 112.2 kN-m b) 96.6kN-m c) 136.8kN-m d) 105.8 kN-m Ans:
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SUB: STRUCTURAL ANALYSIS MODULE-31C 34. A live load 20 kN/m, 6 m long moves on a simply supported girder AB 12 m long. For maximum bending moment to occur at 4 m from left end A, where will the head of load be, as measured from A? a) 4 m
b) 6 m c) 8 md) 10 m
Ans:
35. The influence line for vertical reaction at A of the beam is
Ans: (a)
36. The Muller-Breslau principle in structural analysis is used for a) b) c) d)
Drawing influence line diagram for any force function Superimposition of load effects Writing virtual work equation None of above
Ans: (a)
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