- 9 -
SELF-ASSESSMENT QUESTIONS:
Before studying any more topics attempt the following questions.
The solutions are shown at the end of this unit.
1.
The steel plate A in the figure is 100 mrn
and 16 mm thick. Calculate the load W
which will produce a maximum combined
stress of 69 MPa in the plate.
~.vtde
w
2.
A 60.3 mm-diameter 3.2 rnm-wall steel pipe
extends vertically out of a solid
support as shown. Calculate the value
of P which will produce a combined stress
of 150 MPa when h = 500 mm and 8 = 30°
For pipe A = 583 mm2
I = 0.238 x 10 6 mm~
X
3.
Member AB of the crane shown is a
steel universal section, 150UC 23,
and its length L is 2.4m. Calculate the
maximum combined stress in AB when a load
of 22.5 kN is applied at the mid-point and
mass of beam and its deflection are
neglected.
For 150UC 23 A = 2980 mm 2
I = 12.6 x10 6 mm 4
X
Beam height 152 mm.
4.
A section of 60.3 mm diameter 3.2 mm wall
steel pipe is solidly embedded in a
concrete footing, as shown· Calculate
the stresses on the left and right side
of the vertical portion of the
pipe when P = 2.2 kN and d = 500 mm.
For pipe A = 583 mm2
I X = 0.238 x 10 6 mm 4
7703P: 6
-
16 :...
SELF-ASSESSMENT QUESTIONS
Before studying any more topics attempt the following
questions.The solutions are shown at the end of this unit.
Calculate the principal stresses and maximum shear
stresses for the following stress conditions.
5.
f
f
f
6.
f
f
f
7.
f
f
f
8.
f
f
f
7703P: 6
=
10 MPa
y
=
15 MPa
s
=
8 MPa
=
50 MPa
y
=
40 MPa
s
=
20 MPa
=
50 MPa
y
=
40 MPa
s
=
0 MPa
=
30 MPa
y
=
0 MPa
s
=
20 MPa
X
X
X
X
- 23 -
SELF-ASSESSMENT QUESTIONS
Before studyinq any more topics attempt the following
questions. The solutions are show at the end of this unit.
9..
A 25 mm shaft is subjected to a torque of 50 Nm and a
bending moment of 80 Nm.
Calculate:
10.
(a)
The equivalent torque.
(b)
Equivalent moment.
(c)
Max. shear stress.
(d)
max. tensile stress.
G-ea,-
100-
Calculate:
7703P: 6
100
'2.000N
(a) --Torque.
(b)
Bending moment at gear
(c)
Equivalent torque.
(d)
Equivalent moment.
(e)
Max. sheer stress.
(f)
Max. tensile stress.
- 24 (Self-Assessment Questions continued)
11.
A shaft carried a torque of 75 Nm and a bending moment
of 100 Nm. The allowable shear stress is 50 MPa and
the allowable tensile stress is 60 MPa. What size
should the shaft be?
12.
For the shaft shown, a = 150 rnrn, b = 300 rnrn,
C = 375 rnm, r = 200 rnrn, r
= 100 rnrn, W = 270N,
W
=
1
2
2
= 135N, T
225N, T
1
1
= 45N, T
2
= 135N and T
3
= 315N.
"
Calculate the required shaft diameter D if the perrnissable
stress
is 56 MPa
c
7703P:
6
- 25 -
SOLUTIONS TO SELF-ASSESSMENT QUESTIONS
12.5
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--
b "'~
--
l~
--
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M Pt x
S-nt£.-SS
~3 X
w
fs,
+-r
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c.
W\M
C.C...Uil-~
0
4
A
t\-r
\2 ~
X
--
My
--
\tJx \2 s- X
\· ~~ )(' to"
I
5o
F
A
--
w
-\A.t>.~ ~&!N'-0
3
\0
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--
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\oo
X
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~~Dwc..
M
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l2...
+--
l'-00
-rl
64
--
.{2.~ +
W'X \L.S""x ~0 -4-
w
--
\ 1.· 7 kN
S,.11..£,SS
\·
~l x toe
w
\k.OO
-
-26 -
Problem 2.
Pc..os :;o
-
'
500
7 . .7 / - / v / / . / / /
.{:a ==- N\
\.j
:r.'
Yc....os a
x
5Cx:>
0· 2~~
)C
to~
X"
10· (5"
~
--\J\ !). )(
GoY\.~ (1\.1~0
t
\S"D
p
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-
--
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+~ +- +CP~!. b0° .>e ~OOx ~0·[) + p t..CJs3oo
0· L~~
L1.
~
X/0
24
6
N
~B1
-
27 -
Problem. 3.
v
~-
u
ISouc.
23/
1"2...
H
\\•2s'1.7
~ 11·25 kN
Y:4
'1122.:5
kN
ll·2.5"k~
~f------------t
ISOUC23 /
K
H
k~
\.:,s-
\· ~s
k~
W\
N \MM
x toG.
My
r
0
l· ~S x lO
\2•'-
x 7b
X lO'-
Mfa.
El· 4
F
J.\
1./ X (O
>
29~0
<;, ~e:.-ss
4= g +
B (· 4
-fc_
-t
'1 0 • 4-b
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q. ok,
u f «-
\l.
-
5
-
28 -
Problem. 4.
. -Rpe
OD 60·3
Wa 11 3·2 mi'Y'I
--~·
d
500
M\.f
r_'
>
1..·2.. x to x Soo x '?:,a-t$'"
o · 2. ~ ~ x toG.
\ 3 C\ \1\ ~Ct.
F
A
:!>
'1.-2 X(O
s-s~
~•
ts<=t -1·77
t 3 5" • 2 M Pa..
-f.
0 c..c.. u a_
s
01\.J fj...£ f.
CoMP~~sstvE-
~. s oCL~<;,
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7/ Mfct..
L E. Pr 1-f AN !J S' I Dt:. or=- "1"+-4 E.. fl P.
S-nz.e...s 5
f
fB + ~c_
l ~ '\ + s. 77
~
l A-2o 2>
OtU -r"H£..
MPC(_
Rl~J.r~ ~two ~~OE.. CJF=--TU£ P1f£
...;. 29 -·
Problem. 5 .
+ +~
+X
{I ) .f:L
2.
·~
\2.
s- -+
\0 ..r
.f.,
-
B •
a ·s ~
3~
M fct.
lA p<t..
6.
C...;
+')(+
.(:., )+-'l
2.
bO +40
-
'L
~
4S"
+
jVx.; .f,'f )' + (l.
+
J(~0;4-0 J
z + 20
1-0·b
t,
~5ob
MPCL
f,_
2_4 ..
4LOob
MP~
9
·-o
:::.
)<
0
0
I,-,
.--.-.
-+
\..-,
!"
,(
,.\
/\
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6
f3't...
M ~C(.
A.... ll.
q
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lo-~tg
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Problem.
+ J~<;}'f-)' + s;s.,_
1..
'.(
0
~~
D
./1
VI
rr-
e
r-
-
IX
Q
0
0
V)
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j'><
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MP((
.,_
-
30 -
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Problem 7.
~\
)
f2.
+~~ !=;i
+
"2..
5""o ""'- Llo
1e
f t- ),_ -~-- {'-
(5o;.a. or~-
-r /
'2...
-t-o
"t..
s-
..I-
4~
)5_7._-
-
.fl
5"o
Mf""
+'t.
4-o
MP~
s
s-
M fee.
Problem. 8.
.C.,
) ..(: 1..
+I~\- +)!r -~- .(s 2.
+)( + .ft
2.
10+0
2...
\5"
6
+
~I
A-o
Mf~
,
-\o
tvH'a..
fL.
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25 MPet.
2!>
~
M Pa..
2o'-
- 31 -
Problem. 9.
-==-
J(5o xu})'+- {l?oxtcl)z.
>
qA. ~~Cf XIO N MM
E~ lV~rNf ~UJ'91fll{, M~~ M~ =
i
(\e.. + M}
== -:i:- {q 4-- ~
~1·
+ go}
Is- N~
\' T¢:
"{1'-- D 3
\ C. x: q4 •S~ Cf
'3
X IV
11 x 25..,.
3o · l
tv1 fct.
S.2 tvt~
1\'-" D !>
12 X ~l·fS
XIO
11 )( 25">
(-_
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5"b·8
MP'l.
>
P rob 1 em • 1 0 •
32 -
2.000N
Gear
/
PCD 5o
IOOON
2DOON
/00
?_Oo 0
2d:J X 2 5"
t-r;p
4C:.·~
~Yv\
\000 X: laO
\oo x
J lz.
to~
-l-
M"'-
j~. ct.
xto
\\0 •
4
..
N
M""'
f +-~oo-xto1)
3
3
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s
f (Te
t ( l \O· 4~
N Mt\1
M)
4-
>dO'S -t- ICO><lct)
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c;- • 2 )( IO
\e:,
T~
)
N Yv\wt
11'-D~
J
l C:. X 110 ·LL~ XIO
"{1"-
)(
L.o • 8
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M
f'C<.
- 33 Problern.11.
---+--)-
0
lfor-ft/12- 7::> Aim
Be/1~"} rnome, .f
/OOAI""'
NM
\25
-&C~-4-M)
+( sl2
+
\\2o~
D10rM.f:."ff.a.. gD.:<::.E.v ON
q
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{c.
o
fe._
D3
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ux-o\
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D
Of\1
f
MA-x
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5-r~t..s S
TE:.NsrL-t.
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1'j"'-
Me.
D
~2. X
l
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N~
M~x 5t.-f~ ~ TltE-S~
s-oBA-Sw
2b·7
D3
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5 Lllt·· ~ \.-tu <;"T g f.. 1H t. LA4.b f.,(L 0 t=- f
-rwo
S 12 ~
1~A-T \ S
l.C::.- 7 hA..n
'f \-\f.
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H £.-S f.
- 34 -
Problem .12.
I
f...
ISO
375
300
Jlloooi
.Rs
LJ.50N
270
+- l
35
+
l.j. 5
'-!-50
225
135
'2>15
-z15
),...-.-.
.-t "
7703P: 6
,_____r_ -·· · -
- 35 -
EQ..VtVM-~1lo~ l~
J-r
= j
2
+M.,_
\c2 +- teo<?. 75l.7_
\C:,4. 7
\C. Te
11 D
t\J\M.
3
3
\b ~ tb"f.7 xiD
11-
o3
24· B
7703P: 6
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