List of HWs
EASC2220
Spring 2023
HW#01 (SKIP)
Q1
Link AB is to be made of a
steel for which the ultimate
normal stress is 450 MPa.
Determine the cross-sectional
area for AB for which the
factor of safety will be 3.50.
Assume that the link will be
adequately reinforced around
the pins at A and B.
Q2
Knowing that the average
normal stress in member BD of
the Pratt bridge truss shown
must not exceed 21 ksi for the
given loading, determine the
cross-sectional area of that
member that will yield the most
economical and safe design.
Q3
Link BD consists of a single wooden
member 36 mm wide and 18 mm
thick. Knowing that each pin has a
12-mm diameter, determine the
maximum value of the average
normal stress in link BD if ϴ = 90°.
Required
HW#02 (Due: 9:30am Feb. 6, bring hard copy)
Q1
Q2
10”
45°
10”
20”
20”
20”
The 1/8 in. diameter cable DG is made of a steel with
29,000 ksi. Knowing that the maximum stress in the
cable must not exceed 70 ksi and that the elongation
of the cable must not exceed ¼ inch, find the
maximum load W that can be applied as shown.
The rigid bar AD is supported by two steel wires of
1/16 -in. diameter (E = 29 × 106 psi) and a pin and
bracket at A. Knowing that the wires were initially
taut, determine (a) the additional tension in each
wire when a 220-lb load P is applied at D, (b) the
corresponding deflection of point D.
A square was scribed on the side of a large steel
pressure vessel. After pressurization the biaxial
stress condition at the square is as shown. Knowing
that E = 29 × 106 psi and v = 0.30, determine the
change in length of (a) side AB, (b) side BC, (c)
diagonal AC.
Suggesting
A rectangular block of material (Structural Steel –
ASTM-A36) is bonded to two rigid horizontal plates.
The lower plate is fixed, while the upper plate is
subjected to a horizontal force P. Knowing that the
upper plate moves through 0.03 in. under the action
of the force, determine (a) the average shearing strain
in the material, and (b) the force P exerted on the
plate.
Suggesting
HW#03 (Due: 02/13/2023)
Q1
Q2
A hole is punched at A in a plastic sheet by applying a
1000-N force P to end D of lever CD, which is rigidly
attached to the solid cylindrical shaft BC. Design
specifications require that the displacement of D
should not exceed 20 mm from the time the punch
first touches the plastic sheet to the time it actually
penetrates it. Determine the required diameter of
shaft BC if the shaft is made of a steel with G of 77.2
GPa and τall of 80 MPa.
Two solid steel shafts are connected by the gears
shown. A torque of magnitude T = 1000 N · m is
applied to shaft AB. Knowing that the allowable
shearing stress is 100 MPa and considering only
stresses due to twisting, determine the required
diameter of (a) shaft AB, (b) shaft CD.
DO NOT LOOK BEYOND THIS SLIDE
• Feb 8
HW#04 (Due: 03/04/2022 – hardcopy)
Draw Shear Force and Bending Moment Diagrams
Q1
2 k/ft
A
5 ft
Q3
Q4
D
10 kips
A
3 ft
B
5 ft
2 ft
5 ft
2 k/ft
5 ft
10 kips
A
10 kips
5 ft
C
C
2 k/ft
B
C
3 ft
3 ft
2 k/ft
3 ft
B
Q2
7 ft
10 kips
B
5 ft
10 kips
A
3 ft
C
2 k/ft
C
2 ft
10 kips
A
3 ft
7 ft
B
Q5
HW#05 (Due: 03/23/2022 – hardcopy)
Draw the shear and bending-moment diagrams for the beam and
loading shown
Draw the shear and bending-moment
diagrams for the beam and loading shown
and determine the maximum normal stress
due to bending.
Knowing that the allowable normal stress for the
steel used is 36 ksi, select the most economical
wide-flange beam to support the loading shown.
HW#06 (Due: 03/28/2022 – hardcopy)
Q1
Q2
A square box beam is made of two
3
4
3
4
 3.5-in.
planks and two  5-in. planks nailed together as
shown. Knowing that the spacing between the nails
is s = 1.5 in. and that the vertical shear in the beam
is V = 200 lb, determine (a) the shearing force in
each nail, (b) the maximum shearing stress in the
beam.
Draw Shear and Moment Diagram. Then,
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.
Q3
Draw Shear and Moment Diagram. Then,
For the beam and loading shown, determine the
minimum required width b, knowing that for the
grade of timber used, σall = 12 MPa and τall = 825
kPa
Q4
Draw Shear and Moment Diagram. Then,
For the beam and loading shown, determine the largest shearing
stress in section n-n.
HW#07 (Due: 04/20/2022 – hardcopy)
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