tutorial 14 01
DESCRIPTION
Bending StressTRANSCRIPT
300 kN
200
150
A= 13744.468
21.8
mm2
s= N/mm2
50 mm
25 mm
100 kN
A= 490.874
203.7
mm2
s= N/mm2
A= 1963.5
50.9
mm2
s= N/mm2
Maximum Stress = 200
25 mm
15 mm 10 mm
12mm Dia.
Cross Sectional Area of Link = 150
F max = 30000 N30 kN
Cross Sectional Area of Eye = 130
F max = 26000 N26 kN
N/mm2
mm2
mm2
F kN
1Tie
L= 5 m
N = 75
A= 500E= 200
1507.500E-04
Elongation= 3.75 mm
2Strut
L= 1.5 m
N = -30
A= 250E= 70
-120-1.71E-03
Elongation= -2.57 mm
mm2
kN/mm2
s = N/mm2
e=
mm2
kN/mm2
s = N/mm2
e=
kN Tension
kN Compression
Stress =
Determine the Percentage change in the volume of the cube
Material E= 1.00E+05Poisson's ratio = 0.25
Assuming cube size is 1000x1000x1000 (could have used 1x1x1)
Delta Long. Delta Lat.
-8.00E-04 -8.00E-01 mm 2.00E-04 2.00E-01
N/mm2
Long. e Lat. e
-80
Original Vol. New Vol. Delta Vol.
mm 1000000000 999599719.968 0.04%
N/mm2
mm3 mm3
1000 mm 50 mm Diameter
Calculate :1. The vertical movement of B2. The total extension3.The Change in lateral dimensions of AB and BC4. The change in volume of the hanger
1000 mm 35 mm Diameter
135 KN 135000 N
Material Steel E= 200Poisson's ratio = 0.3
Stress Delta Long. Delta Lat. Original Vol.
A-B 68.7549 0.000344 0.34377 mm -0.0001031 -0.0051566 mmB-C 140.316 0.000702 0.70158 mm -0.0002105 -0.0073666 mm
Total 1.0454 mm
KN/mm2
Long. e Lat. eN/mm2
3.The Change in lateral dimensions of AB and BC
Original Vol. New Vol.
1963495 1963765962112.75 962382.51
2925608 2926148 -539.64
mm3 mm3
mm3
Stress in Timber Beam (4x2)due overweight Lecturer at midspam
Breadth 50
100 Depth
Load 1962 N
I = 4E+06where b is breadth and d is depth
M 1962 Nm
z max = 50 mm
mm4 I=bd3/12
y y
z max
z max
23.54
23.54 Compression
Neutral Axis
23.54 Tension
s max = N/mm2
N/mm2
N/mm2
Stress in Timber Beam (4x2)due overweight Lecturer at midspam
Me at Midspan 200 kg
Span = 4 m
b is breadth and d is depth
Stress in Concrete Beam due to self weight
Breadth 300
800 Depth
Density Concrete 2400
w 5650.56 N/m5.65056 kN/m
M= 70.632 kNm 70632000 Nmm
I = 1.280E+10where
z max = 400 mm
W top/bot= 32000000
kg/m3
mm4 I=bd3/12
mm3
y y
z
z max
2.21
2.21 Compression
Neutral Axis
2.21 Tension
s max = N/mm2
N/mm2
N/mm2
Span 10 m
b is breadth and d is depth
T Beam subject t 7.00 kNm Moment
100
28.75 15
28.7578.750
100
15
A1 1500 h1 28.75A2 1500 h2 28.75A 3000
Moments of Areas about the Base3000 y' = 1500 50
y' = 78.75 mm
Iyy1 = 2.813E+04Iyy2 = 1.250E+06
Iy'y' = 3.758E+06
1.037E+05
4.772E+04
67.53
146.69
mm4
Wtop = mm3
Wbot = mm3
s top = N/mm2
s bot = N/mm2
y’ y’
67.53
Neutral
146.69
= 7.00L (say) = 10 mw = 0.56
mmmm
+ 1500 107.5
wl2/8
y’
Compression
Axis
Tension
N/mm2
N/mm2
span continuous over one support plus cantilever made from steel box section given
175 kN
2 m 7 m 3
RA + RC = 225 kN
M about A
175 x 2 + 50 x
RC = 105.56 kNRA = 119.44 kN
Moment about end of Cantilever = 0
Check = 0
Therefore
M at B 238.89 kNm
M at C -150 kNm
BMD -150-
B
CA
+
238.89 kNm
Section
250 mm 300
I = 3E+08
zmax top/bot = 150 mm
s max = 102.53
-102.5 N/mm2 Compression
102.5 N/mm2 Tension
mm4
N/mm2
Neutral Axis
span continuous over one support plus cantilever made from steel box section givenSection
50 kN
250 300mm mm
m
12 = RC x 9
kNm
C
mm
Given that the maximum permissible stress 165What is the maximum value of F
70 mm
7
64 mm54.5 mm
102
Standard I section Iyy = 21854.5 mm
7
Underneath the point load
Use paraleel Axis Theorem to Calculate I value at centre
Part Icc Area h
Top Plate 2.00E+03 490 54.5 1455423Standard Beam 2.18E+06 .... 0 0Bottom Plate 2.00E+03 490 54.5 1455423
2.18E+06 2.91E+06 Total I =
zmax = 58 mm
W = 8.78E+04
M = 1.45E+07 Nmm
N/mm2
cm4
Ah2
mm3
14.49 kNm
F = 9.66 kN
Checking Curtailment of Flange Plate
At this point
I = 2.18E+06
zmax = 51 mm
W = 4.27E+04
Based on F = 9.66 M @ D = 9.66264 kNm
Hence the stress at this point = 226.05 which would cause failure
permissible moment 7.05E+06 Nmm7.05 kNm
Based on M = 7.0529 F = 7.05 kN
mm4
mm3
N/mm2
F2 m
A C B
mm
D E
6 m
mm
mm
5.1E+06 mm4
which would cause failure
100 x 50 x 10 PFC (Parallel Flange Channel)s with 10mm cover plates Neglecting self-weight calculate the maximum distributed load on a 10m span ….. Given :
200 N/mm2
10 mm
10 mm
100 mm
10 mm
Part Icc Area hTop Plate 9.17E+03 1100 55 3327500Standard Sections 4.16E+06 .... 0 0Bottom Plate 9.17E+03 1100 55 3327500
4.18E+06 6.66E+06
Total I = 1.1E+07
M = 3.61E+07 Nmm
= 36.1 kNm
smax =
Ah2
mm4
y’y’
=
w = 2.9 kN/m
wl2/8
PFC (Parallel Flange Channel)s with 10mm cover plates Neglecting self-weight calculate the maximum distributed load on a 10m span ….. Given :
I of 1 Channel 208 cm4
w kN/m
10 m Span
y’
Neglecting self-weight calculate the maximum distributed load on a 10m span ….. Given :
Given that:Channel 38 264Universal Beam (UB) 60.8 9500
total 9880 97640000
What are the maximum tensile and compressive stresses on the combined/compound section
8 mm 26.5To Centroid of Channel
Y
310 mm
155 mm
Determine position of Centroid of Compound section
Taking Moments of areas about the Base A z' = Sum(Ai z'i)
9880 z' = 3800 xz' = 207.5 mmztop = 110.5 mm
zbot = 207.5 mm
Use Parallel Axis Theorem to Calculate I value of compound at new centriod
Part Icc Area h
Channel 2.64E+06 3800 84 26812800Universal Beam 9.50E+07 6080 52.5 16758000
Total 9.76E+07 4.36E+07
Area (cm2) Icc (cm4)
mm2
Ah2
Total I = 1.412E+08
70.43 Compression
132.25 Tension
s top = N/mm2
s bot = N/mm2
What are the maximum tensile and compressive stresses on the combined/compound section 20 kN/m
A
mmTo Centroid of Channel
6 m
B.M.D
Mmax = 90 kNm
Mmax = 90000000 Nmm
291.5 + 6080 x 155
Use Parallel Axis Theorem to Calculate I value of compound at new centriod
mm4
mm4
B
Given that:Span = 8 m With Superimposed Load as IndicatedThe density of the Fibre Reinforced Concrete =
What are the maximum tensile and compressive stresses on the section due to a combiantion of self weight and imposed Loa
300 mm
A 60
Fibre Reincorced Concrete I-Beam300 460 mm B
40 mm
Y
z'
C
500 mm
Determine position of Centroid of Compound sectionTaking Moments of areas about the Base
A z' = Sum(Ai z'i)
A 18000 430 7740000B 12000 250 3000000C 50000 50 2500000
Total 80000 13240000
A z' = Sum(Ai z'i)
80000 z' = 13240000z' = 165.50 mm
mm2
Use Parallel Axis Theorem to Calculate I value of A,B & C about this centriod
Part Icc Area hA 5.4000E+06 18000 264.50 1.26E+09B 9.0000E+07 12000 84.50 8.57E+07C 4.1667E+07 50000 115.50 6.67E+08
Total 1.3707E+08 2.0120E+09
Total I =
Bending Moment due to self weight
Volume of Beam = Area x Length = 80,000 x
Therefore Weight = 0.08 x 2400 x 9.81
= 1.88352 x
= 15.07 Knm
Bending Moment due to self weight
Reaction VA = VB = 6.25 x 4 / 2
Therefore Maximum Moment (at midspan) = 12.5 x 4
= 37.50 Knm
Stresses due to combined Moment
Combined Maximum Moment (at midspan) = 15.07 + 37.50
Due to Combined loading the maximum tensile and compressive stresses on the section
7.20 Compression
4.05 Tension
Ah2
Therefore Maximum moment at midspan = wl2/8
s top = N/mm2
s bot = N/mm2
With Superimposed Load as Indicated2400
What are the maximum tensile and compressive stresses on the section due to a combiantion of self weight and imposed Loa 6.25 kN/m
A
mm
2 m 4 m
8 m
Fibre Reincorced Concrete I-Beam
Y
B.M.D SDL
100 mm Mmax (SDL)= 37.5 kNm
Mmax (SW)= 15.06816 kNm
kg/m3
mm3
Use Parallel Axis Theorem to Calculate I value of A,B & C about this centriod
2.1490E+09
2.15E+09
1 = 0.08
= 1.88352 kN/m
8 / 8
= 12.5 kN
- 12.5 x 1
= 52.57 Knm
Due to Combined loading the maximum tensile and compressive stresses on the section
7.20E+00
4.05E+00
mm4
m3/m
2
B
2 m