250+ TOP MCQs on Eccentrically Loaded Riveted Joints and Answers

Machine Design Multiple Choice Questions on “Eccentrically Loaded Riveted Joints”.

Figure 1

Answer the following questions in context to figure 1.
1. A bracket is attached to a vertical wall by means of four rivets. Find the rivet which is under maximum stress.
a) 1 and 4
b) 2 and 3
c) 3 and 1
d) 4 and 2
Answer: a
Clarification: Primary Shear act vertically upward on all the rivets. Secondary shear is proportional to the distance from CG. Hence rivets 1 and 4 are under maximum stress.

2. Calculate the primary shear stress on each rivet if P=30kN and diameter of rivets is 15mm.
a) None of the listed
b) 21.2 N/mm²
c) 42.4N/mm²
d) 169.6 N/mm²
Answer: c
Clarification: τ₁=P/4A or 7500/A.

3. If secondary shear stress acting on any bolts is given by Cxr₁ where r₁ is the distance of bolt from CG, then find the value of C. Bolts are equidistant with spacing of 100mm. Force P=30kN.
a) 46
b) 50
c) 72
d) 64
Answer: c
Clarification: C=Pe/[r₁²+r₂²+r₃²+r₄²].

4. Calculate the effective force in vector form to which rivet 2 is subjected. Bolts are separated by 100mm and force P=30kN.
a) 7500j+3600i
b) 7500j-3600i
c) -7500j-3600i
d) None of the listed
Answer: b
Clarification: Primary force=7500j, Sec Force=Cx50(-i) where C=72.

5. Calculate the effective force in vector form to which rivet 4 is subjected. Bolts are separated by 100mm and force P=30kN.
a) 7500j+7200i
b) None of the listed
c) 7500j+7200i
d) 7500j+7200i
Answer: d
Clarification: Primary force=7500j, Sec Force=Cx100 i where C=72.

6. Calculate the diameter of the rivets if permissible shear stress is 60N/mm². Bolts are separated by 100mm and force P=30kN.
a) 10mm
b) 12mm
c) 13mm
d) 15mm
Answer: d
Clarification: Magnitude of force acting on Bolt 4 or Bolt 1=√7500²+7200² or 10396.6=πd²τ/4.

7. Are the bolts 2 and 3 under same force?
a) Yes
b) No
c) Depends on nature of force whether it is of shear or bending in nature
d) Can’t be determined
Answer: b
Clarification: Primary shear force is same but secondary shear forces direction are different in the two bolts.

8. Are the bolts 2 and 3 subjected to same magnitude of force?
a) True
b) False
Answer: a
Clarification: Although the vectors are different for the forces on two bolts but their magnitudes are same.

9. Can we use the rivets of diameter 18mm in the following case if P=30kN and bolts are separated by 100mm each. Maximum permissible shear stress is 60N/mm².
a) Always
b) Never
c) In some cases
d) Cannot be determined
Answer: a
Clarification: The minimum diameter required for the rivets is obtained 15mm. Any rivet greater than this diameter is safe to use.