Total No. of Questions : 8]
[1] [Total No. of Printed Pages : 4
Roll No ..................................
CE-305-CBGS
B.Tech., III Semester
Examination, December 2020
Choice Based Grading System (CBGS)
Strength of Materials
Time : Three Hours
Maximum Marks : 70
Note: i) Attempt any five question.
{H$Ýht nm±M àíZm| H$mo hb H$s{OE&
ii) All questions carry equal marks.
g^r àíZm| Ho$ g_mZ A§H$ h¢&
iii) In case of any doubt or dispute the English version
question should be treated as final.
{H$gr ^r àH$ma Ho$ g§Xho AWdm {ddmX H$s pñW{V ‘| A§JO
o« r ^mfm
Ho$ àíZ H$mo A§{V‘ ‘mZm Om¶oJm&
1. a) Define the following terms.
{ZåZ{b{IV H$mo n[a^m{fV H$s{OE&
i) Young’s Modulus of Elasticity
ii) Poisson’s ratio
iii) Hook’s Law Mohr’s Circle of Stress.
b) A concrete column of cross-sectional area of
350×350 mm is reinforced by four longitudinal 30mm
diameter round steel bars placed at each corner. If the
column carries comprehensive load of 400kN, determine
comprehensive stresses produced in the concrete and
steel bars. Assume that Young’s modulus of elasticity of
steel is 15 times of that concrete.
CE-305-CBGS
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[2]
EH$ dJuH¥$V H$m§H«$sQ> Ho$ 350×350 mm ñV§^ _| 30mm ì`mg H$s
Mma N>‹S>| Mmam| {H$Zmam| na bJmE JE h¡& `{X Bg ñV§^ Ho$ Cna
400kN H$m EpŠg`b bmoS> bJm {X`m Om`o Vmo ~Vm`o H$s H$m§H«$sQ>
Am¡a ñQ>rb H$s N>‹S>m| _§o {H$VZr H$åàohopÝgd stresses CËnÞ hmoJr?
{X`m J`m h¡ H$s ñQ>rb H$m ¶§Jg _m°S>w bg
w Am°\$ BbmpñQ>{gQ>r H$m§H$« sQ>
Ho$ `m|Jog _m°Sw>bwg Am°\$ BbmpñQ>{gQ>r H$m 15 JwZm h¡&
2. a) Find the free end deflection in cantilever beam with
uniformly distributed load by Maculay’s method.
_¡H$mbo {d{Y Ûmam g_mZ én go {dV[aV ^ma Ho$ gmW H¢$Q>rbrda YaZ
_§o _wŠV {gao na PwH$md kmV H$s{OE&
b) Derive the expression of the value of constant (h2) in
curved beam for rectangular cross section area beam.
Am`VmH$ma AZwàñW H$mQ> joÌ H$s YaZ Ho$ {bE Kw_mdXma YaZ _|
pñWa (h2) Ho$ _mZ Ho$ {bE ì`§OH$ àmá H$s{OE&
3. a) Derive the expression for shear stress distribution over
I-section.
I-go³gZ na H$V©Z à{V~b {dVaU Ho$ {bE 춧OH$ àmßV H$s{OE&
b) The Young’s Modulus of material is 21×104 N/mm2 and
its modulus of Rigidity is 8.4×104 N/mm2 and determine
its Poisson’s ratio and Bulk modulus.
{H$gr nXmW© H$m ¶§J ‘mnm§H$ 21×104 ݶyQ>Z/{‘br‘rQ>a2 VWm H$R>mao Vm
‘mnm§H$ 8.4×104 ݶyQ>Z/{‘br‘rQ>a2 h¡& BgH$m nm°¶OZ {Zîn{Îm
(AZwnmV) Am¡a ~ëH$ ‘mnm§H$ kmV H$s{OE&
4. a) What do you understand by shear centre? Also write its
importance.
H$V©Z Ho$ÝÐ go Amn ³¶m g‘PVo h¡? BgHo$ ‘hÎd H$mo ^r {bIo&
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b) Determine the principal moment of Inertia for unequal
angle section (60×40×6)mm.
EH$ Ag‘mZ H$moU IÊS> 60mm×40mm×6mm Ho$ {bE ‘w»¶
OS>Ëd AmKyU© H$m 춧OH$ àmßV H$s{OE&
5. a) What is meant by effective length of a column? Also define
Slenderness Ratio.
Column (ñV§^) H$s “effective length” go Š`m g_PVo
gmW hr slenderness ratio H$mo ^r n[a^m{fV H$s{O`o&
hmo?
b) Find an expression for crippling load for a long column
when both ends of column are fixed.
EH$ long column {OgHo$ XmoZm| ends fixed h¡ Ho$ crippling load
Ho$ {bE expression H$mo {ZH$m{b`o&
6. Write short notes (any three)
g§{já {Q>ßnUr {b{IE&
a) Differentiate column and struts.
H$m°b‘ Am¡a ñQ´>Q> ‘| {d^oX H$s{OE&
b) Define the point of contra-flexure in a beam.
YaZ ‘| Z{V n[adV©Z {~ÝXþ H$mo n[a^m{fV H$s{OE&
c) Assumption for pure Torsion theory.
ewÕ ‘amoS> Ho$ {bE YmaUmE± {b{IE&
d) Define flexural rigidity and its significance.
‘amoS> H$R>moaVm ³¶m h¡? Cn¶mo{JVm ~VmBE&
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7. a) The stresses at point of a machine component are 150MPa
and 50MPa both tensile. Find the intensities of normal
shear and resultant stresses on a plane inclined at an angle
of 55° with the axis of major tensile stress. Also find the
maximum shear stress magnitude.
_erZ KQ>H$ Ho$ {H$gr {~ÝXþ na 150MPa Am¡a 50MPa H$m VZmd
à{V~b bJ ahm h¡& _w»` VZmd à{V~b Aj go 55° PwHo$ EH$
g_Vb na gmYmaU H$V©Z VWm n[aUm_r à{V~b H$s Vrd«Vm kmV
H$s{OE& A{YH$V_ H$V©Z à{V~b H$m n[a_mU ^r kmV H$s{OE&
b) Write the assumption of theory of simple bending and
prove the relations,
M σ E
= =
I
y R
gab Z_Z {gÕmÝV H$s YmaUmE± {b{IE VWm
M σ E
= = _|
I
y R
g§~§Y ñWm{nV {H${OE&
8. Briefly define any three of the following.
{ZåZ{b{IV ‘| go {H$Ýht VrZ H$m g§{já {ddaU Xr{OE&
a)
b)
c)
d)
Principal Planes
Temperature Stresses
Stresses distribution in thin pressure vessels
Concept of Pure Torsion
******
CE-305-CBGS
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