2nd stage /Mechanical Eng.
Sheet No. 2: Chapter 6
Strength of materials
Q1/ For the beam and loading shown, consider section n-n and determine (a) the largest shearing stress
in that section, (b) the shearing stress at point a.
Ans:
Q2/ The composite beam shown is made by welding C200×17.1 rolled-steel channels to the flanges of a
W250 80 × wide-flange rolled-steel shape. Knowing that the beam is subjected to a vertical shear of 200
kN, determine (a) the horizontal shearing force per meter at each weld, (b) the shearing stress at point a
of the flange of the wide-flange shape.
Ans: a) q=146 kN/m
b)
19.99 kN/mm2
2nd stage /Mechanical Eng.
Sheet No. 2: Chapter 6
Strength of materials
Q3/ The assembly is subjected to a vertical shear of V=7 kips . Determine the shear flow at points A and
B and the maximum shear flow in the cross section.
Ans: qA=196 Ib/in
qB= 452 Ib/in
qmax = 641 Ib/in
Q4/ The beam is constructed from two boards fastened together with three rows of nails. If the
allowable shear stress for the wood is 150 psi, determine the maximum shear force V that can be
applied to the beam. Also, find the maximum spacing s of the nails if each nail can resist 650 lb in shear.
Ans: V=1.8 kip
S=2.167 in
2nd stage /Mechanical Eng.
Sheet No. 2: Chapter 6
Strength of materials
Q5/The box beam is constructed from four boards that are fastened together using nails spaced along
the beam every 2 in. If each nail can resist a shear of 50 lb, determine the greatest shear V that can be
applied to the beam without causing failure of the nails.
Ans: V= 317 Ib