ES230 Strength of Materials Lesson 5: Stress III - Lafayette ...ES230 Strength of Materials Lesson...
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ES230 Strength of Materials Lesson 5: Stress III
ES230 Strength of Materials Lesson 5: Stress III - Lafayette ...ES230 Strength of Materials Lesson 5: Stress III 3. The 3”x1/8” plate shown is connected to the larger plate with
2. The hangers support the joists uniformly, so that it is
assumed the four nails on each hanger carry an equal portion of the
load. Determine the smallest diameter nails at A and at B if the
allowable shear stress for the nails is allow = 4ksi. The hangers
only support vertical loads.
2 nails on each side (4 total, per hanger)
ES230 Strength of Materials Lesson 5: Stress III
3. The 3”x1/8” plate shown is connected to the larger plate with
(4) 3/8” diameter bolts in 3/8” diameter holes in single shear, as
shown. Investigate the three following failure modes, then
determine which failure mode is the weakest so that you can report
the maximum tension that the connection can withstand:
A. Tensile Fracture – See illustration, below, showing fracture
path ab. B. Block Shear – See illustration, below, showing fracture
path cdef. The key to this problem is
understanding that some area has shear stress on it and some
area has normal stress on it. However, if this failure occurs, the
shear areas will have reached the ultimate shear stress and the
normal areas will have reached the ultimate normal stress.
C. Bolt Shear Given: The ultimate normal stress for all
materials (bolts and plates) is = 50 ksi. The ultimate shear stress
for all materials is = 30 ksi.
1”
1”
1”
1” 1”
P Top View
P 1/8”
Side View
P
A). Fracture along path ab
a
b
P
B). Block Shear along path cdef
cf
d
e
ES230 Strength of Materials Lesson 5: Stress III
ES230 Strength of Materials Lesson 5: Stress III
ES230 Strength of Materials Lesson 5: Stress III
4. The wooden joint is subjected to the axial member force of
5kN. Determine the average normal stress acting on sections AB and
BC. Assume that the connection is smooth (no FRICTION). The members
are 50-mm thick (this is the dimension into the page). Note: BC is
horizontal
