Type
Solution Manual
Book Title
Statics and Mechanics of Materials 2nd Edition
ISBN 13
978-0073398167

### 978-0073398167 Chapter 8 Solution Manual Part 6

February 21, 2020
PROBLEM 8.46
Solve Prob. 8.45, assuming that the structure has been redesigned to use
5
16
-in-diameter pins at A and C as well as at B and that no other changes
PROBLEM 8.45 Link AC is made of a steel with a 65-ksi ultimate
normal stress and has a
11
42
×
-in. uniform rectangular cross section. It is
connected to a support at A and to member BCD at C by
3
8
-in.-diameter
pins, while member BCD is connected to its support at B by a
5
16
-in.-
diameter pin. All of the pins are made of a steel with a 25-ksi ultimate
shearing stress and are in single shear. Knowing that a factor of safety of
3.25 is desired, determine the largest load P that can be applied at D.
Note that link AC is not reinforced around the pin holes.
PROBLEM 8.47
Each of the two vertical links CF connecting the two horizontal
members AD and EG has a 10 40-mm uniform rectangular cross
section and is made of a steel with an ultimate strength in tension of
400 MPa, while each of the pins at C and F has a 20-mm diameter and
are made of a steel with an ultimate strength in shear of 150 MPa.
Determine the overall factor of safety for the links CF and the pins
connecting them to the horizontal members.
PROBLEM 8.48
Solve Prob. 8.47, assuming that the pins at C and F have been replaced by
pins with a 30-mm diameter.
PROBLEM 8.47 Each of the two vertical links CF connecting the two
horizontal members AD and EG has a 10 40-mm uniform rectangular
cross section and is made of a steel with an ultimate strength in tension of
400 MPa, while each of the pins at C and F has a 20-mm diameter and are
made of a steel with an ultimate strength in shear of 150 MPa. Determine
the overall factor of safety for the links CF and the pins connecting them
to the horizontal members.
PROBLEM 8.49
A 40-kN axial load is applied to a short wooden post that is
supported by a concrete footing resting on undisturbed soil.
Determine (a) the maximum bearing stress on the concrete
footing, (b) the size of the footing for which the average bearing
stress in the soil is 145 kPa.
PROBLEM 8.50
The frame shown consists of four wooden members, ABC,
DEF, BE, and CF. Knowing that each member has a 2 × 4-in.
rectangular cross section and that each pin has a
1
2
-in.
diameter, determine the maximum value of the average
normal stress (a) in member BE, (b) in member CF.
PROBLEM 8.51
Two steel plates are to be held together by means of 16-mm-
diameter high-strength steel bolts fitting snugly inside cylindrical
brass spacers. Knowing that the average normal stress must not
exceed 200 MPa in the bolts and 130 MPa in the spacers,
determine the outer diameter of the spacers that yields the most
economical and safe design.
PROBLEM 8.52
When the force P reached 8 kN, the wooden specimen shown failed in
shear along the surface indicated by the dashed line. Determine the
average shearing stress along that surface at the time of failure.
PROBLEM 8.53
Knowing that the link DE is
1
8
in. thick and 1 in. wide, determine
the normal stress in the central portion of that link when
(a)
0,
θ
= °
(b)
90 .
θ
= °
PROBLEM 8.54
A steel loop ABCD of length 5 ft and of
3
8
-in. diameter is placed as
shown around a 1-in.-diameter aluminum rod AC. Cables BE and DF,
each of
1
2
-in. diameter, are used to apply the load Q. Knowing that the
ultimate strength of the steel used for the loop and the cables is 70 ksi,
and that the ultimate strength of the aluminum used for the rod is 38 ksi,
determine the largest load Q that can be applied if an overall factor of
safety of 3 is desired.
PROBLEM 8.55
The hydraulic cylinder CF, which partially controls the position of rod
DE, has been locked in the position shown. Member BD is 15 mm
thick and is connected at C to the vertical rod by a 9-mm-diameter
bolt. Knowing that P = 2 kN and
75 ,
θ
= °
determine (a) the average
shearing stress in the bolt, (b) the bearing stress at C in member BD.