design of self supporting steel chimney for wind loads as...
TRANSCRIPT
Sheet :
Cont'd :
this only
Design of Self supporting Steel Chimney forData Wind Loads as per India Standards.
Prepared by : Date :
Job No. :
Verified by :
CALCULATION
Note : Enter Data in Cells marked
Height of Steel Chimney 80.00 m
Outside Diameter at Top 3.00 m
Revision Notes :
Calculation Sheet
Project :
3 mm
Subject :
Consider outside diameter of the chimney at base dbase :=
5.00 m
Shape factor of Steel chimney circullar in plan.0.70
Adopt height of Flared Portion 25.00 m
Minimum outside diameter of flared chimney at base = 1.60*Dtop 4.80 m
Intensity of Wind Pressure upto a height of 30 m as per Is 875 1.50 kn/m2
Recommended height of Flared Portion = H/326.67 m
Yeild stress of Chimney Steel as per IS 2062-2006 fy = 250 mpa
Temperature of Steel Chimney 400 °C
External corrosion allowance Tce mm (ref.Table-1; IS-6533 part-2:1989 for non-copper bearing steel and design life 20 years)
Temperature Coefficient Kt 0.50
mm
Load Combinations Reference: clauses 6.5, IS 6533(Part-2):1989
(a) Dead load+ Wind load
(b) Dead load+ Load due to lining+ Imposed load on service platforms + Wind load
2: Forces acting on Steel Chimney : = density of steel =
1) Self weight of chimney .
Ws = . (π d) . (t) .(h)
Ws = Ws (tension) Ws = 1.2 . Ws (compression)
2) Weight of Lining . = density of lining =
Ws = . (π d) . (t) .(h) = thickness of lining =
efficiency of joint on tension side ηt =efficiency of joint on tension side ηc =
Internal corrosion allowance Tci mm (ref.Table-1; IS-6533 part-2:1989 for non-copper bearing steel and design life 20 years)
Unit wt of Brick lining 20.12 kn/m3
Steel density 78.50 kn/m3
Consider a shell thickness = TtopA 6
Ttop = TtopA + Tce + Tci = 6 + 3 + 5 = 14 mm
Thickness of Brick Lining 100 mm
5 mm
Minimum thickness of the shell without corrosion = Tmin = dtop/500 6 mm
0.70
1.00
Weight of the (platform+ access ladder+ helical strake+ rain cap +
etc) is assumed to be 20% of the self weight of chimney shell.ρ
78.50 kn/m3
ρ
ρ
20.12 kn/m3
t 100.00 mm
Allowable tensile stress in steel plate as per IS 800-2007 = 0.6*fy*kt*ηt = 53 mpa
200000 mpaE = Youngs modulus of Elasticity of steel
ρ
Prep By : A B Quadri- Abq Consultants - 9959010210 - [email protected]/2 Royal Residency, Besides Amba talkies, Mehdipatnam , Hyderabad-500028-www.abqconsultants.com
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This program Designs and
Optimises Steel Chimney and
the RCC Foundation.
Written and programmed by
:-
A B Quadri
www.abqconsultants.com
9959010210
9959010211
Wind Pressure , Moment and Shear from Top at every Segment
Nos of horizontal Segments chimney divided into = Each Segment depth m.
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25 3.20
s .n
o
Height from ground
Wind Pressure
diameter effective D = D*0.7
Force on each
segment P @
cg
Shear @
bottom of each
segment
Moment @ bottom of each
segment.
m kn/m2 m D*S.f Kn Kn Kn.m
80.00 1.73 3.00 2.10 11.60
76.80 1.72 3.00 2.10 11.53 12 37
0 0
73.60 1.71 3.00 2.10 11.46 23 111
70.40 1.69 3.00 2.10 11.39
67.20 1.68 3.00 2.10 11.31 46 369
35 222
64.00 1.67 3.00 2.10 11.23 57 552
60.80 1.66 3.00 2.10 11.15
57.60 1.65 3.00 2.10 11.06 80 1026
69 771
54.40 1.63 3.00 2.10 10.97 91 1317
51.20 1.62 3.00 2.10 10.88
48.00 1.60 3.00 2.10 10.78 113 2002
102 1642
44.80 1.59 3.00 2.10 10.67 123 2397
41.60 1.57 3.00 2.10 10.56
38.40 1.55 3.00 2.10 10.44 145 3289
134 2826
35.20 1.53 3.00 2.10 10.31 155 3785
32.00 1.51 3.00 2.10 10.17
28.80 1.50 3.00 2.10 10.08 176 4876
165 4314
25.60 1.50 3.00 2.10 10.08 186 5470
22.40 1.50 3.19 2.23 10.71
19.20 1.50 3.42 2.39 11.48 206 6756
196 6096
16.00 1.50 3.65 2.55 12.26 218 7454
12.80 1.50 3.88 2.71 13.03
9.60 1.50 4.11 2.88 13.81 243 8968
230 8190
6.40 1.50 4.34 3.04 14.58 257 9790
3.20 1.50 4.57 3.20 15.35 272 10659
0.00
10.00
20.00
30.00
40.00
50.00
60.00
70.00
80.00
90.00
0.00 0.50 1.00 1.50 2.00
Wind pressure diagram
Wind force
He
igh
t in
me
ters
Wind pressure KN/m2
9959010211
24
25
3.20 1.50 4.57 3.20 15.35
0.00 1.50 4.80 3.36 0.00 287 11577
272 10659
Prep By : A B Quadri- Abq Consultants - 9959010210 - [email protected]/2 Royal Residency, Besides Amba talkies, Mehdipatnam , Hyderabad-500028-www.abqconsultants.com
-10.00
0.00
10.00
20.00
30.00
40.00
50.00
60.00
70.00
80.00
90.00
0.00 2000.00 4000.00 6000.00 8000.00 10000.00 12000.00 14000.00
Moment Diagram
Moment Diagram
-10.00
0.00
10.00
20.00
30.00
40.00
50.00
60.00
70.00
80.00
90.00
0.00 50.00 100.00 150.00 200.00 250.00 300.00 350.00
Shear Diagram
Shear Diagram
Shear Force in KN
He
igh
t in
me
ters
He
igh
t in
me
ters
Moment in Kn.m
-10.00
0.00
10.00
20.00
30.00
40.00
50.00
60.00
70.00
80.00
90.00
0.00 0.50 1.00 1.50 2.00
Wind pressure diagram
Wind force
He
igh
t in
me
ters
Wind pressure KN/m2
9959010211
4 : Thickness of Chimney Plate without corrosion allowance :
0
1
2
3
4
5
6
7
8
9
10
11
12
667
0.08316 340.92 728
0.08316
303
425
0.05544 151.52 485
0.06930
Kn
0.04158 0 0
0.04158 14.21
Ok
29.23
36.96 36.96
14.933 7.467 36.96 36.96
38400 12.800 6.400 29.23 29.23
Ok
Ok
0.00 3000
30006
500
19.20 30006
500
16.00 30006
500
12.80 30006
500
10300
28.80 300010
300
Ok
Ok
Ok
Ok
Ok
Ok
Ok
6400 2.133 1.067
32000 10.667
51200 17.067 8.533
44800
Ok
Ok
Ok
Sect
ion M
odulu
s Z
=
0.7
7 d
2 t
Self w
t W
s fr
om
top
Wt
of
Lin
ing f
rom
top
s .n
o
Heig
ht
from
top
dia
mete
r of
chim
ney
from
top
Thic
kness
of
Ste
el Pla
te
without
corr
osi
on
D/t ratio
m3 Kn
0.00
mm N/mm2
Allow
able
str
ess
in
bendin
g a
s per
table
3 *
kt
N/mm2
Eff
ect
ive h
eig
ht
for
axia
l st
ress
h1
ratio h
1/D
for
axia
l st
ress
ratio h
1/D
for
bendin
g s
tress
=
0.5
*h1/D
Allow
able
str
ess
in
axia
l co
mpre
ssio
n a
s per
table
3
*
kt
8375
22.40 30008
375
6500
m mm mm
29.23
19200 6.400 3.200 29.23
4.267 29.23
5.333
0 0.000 0.000 0.00
3.20
38.40 300012
250
9.60 30006
500
6.40 30006
500
35.20 300012
25.60 3000
250
32.00 3000
45.90
29.23
12800 4.267 2.133 29.23 29.23
49.41
70400 23.467 11.733 47.56 49.41
64000 21.333 10.667 43.50 43.69
43.69 43.69
76800 25.600 12.800
29.23
29.2325600 8.533
29.23
57600 19.200 9.600
364
0.05544
213.08 546
0.06930 236.75 607
312.51
85.23
132.58
182
0.04158 56.82 243
0.04158 71.03
0.04158
61
0.04158 28.41 121
0.04158 42.62
13
14
15
16
17
18
19
20
21
22
23
24
25
Prep By : A B Quadri- Abq Consultants - 9959010210 - [email protected]/2 Royal Residency, Besides Amba talkies, Mehdipatnam , Hyderabad-500028-www.abqconsultants.com
0.25999 1426.71 1828
57.84
789
0.09702 464.03
56.95
54.13
54.13
0.35482 1894.00 2427
58.53
568.20
1032
1160
850
341820
171
57.60 318720
159
54.40 300020
60.80
Ok
Ok
80.00 480020
240
76.80 457020
228
73.60 433920
217
70.40
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
44.80 300014
214
41.60 300014
214
51.20 300016
188
48.00 300016
188
410920
205
67.2020
194
64.00 364820
182 128000 35.088 17.544 45.57
3878
14.933 46.58
27.733 13.867 48.43
96000 32.000 16.000 47.81
134400 34.653 17.327 44.72
150
83200
45.88
61.37
108800 36.267 18.133 47.35 62.25
102400 34.133
160000 33.333 16.667 40.84 50.68
153600 33.613 16.807 41.83 52.20
147200 33.923 16.962 42.82 53.76
140800 34.268 17.134 43.79 55.35
57.84
89600 29.867
121600
0.23165
1476
910
0.11088 606.08 971
0.09702 430.89
0.17987 1313
0.20494 1151.55
1024.8835.581 17.790 46.29 60.03
115200 36.145
17.067
0.13860 804.95
0.15644 905.49
0.11088
18.072 46.79
0.32157 1730.97 2218
0.28996 1575.20 2019
1285.50 1647
0
1
2
3
4
5
6
7
8
9
10
18
16 Ok
Ok
Ok
16
Tota
l th
ickness
of
Ste
el p
late
re
quir
ed w
ith inte
rnal and e
xte
rnal
corr
osi
on =
SW
tota
l
mm
14
14
14
14
14
Ok
Ok
14
Ok
Ok
Ok
Ok
Ok
Ok
Thic
kness
check
28.894 -26.382
8.872 -7.867
-12.024
-17.045
18.513 -16.754
23.749 -21.740
23.696 -21.435
tensi
le a
nd c
om
pre
eiv
e s
tress
due
to w
ind.
Win
dw
ard
sid
e t
ensi
le s
tress
in
steel due t
o (
Win
d +
Self w
t of
Chim
ney.)
N/mm2 N/mm2
0.000 0.000
0.892 -0.641
2.672 -2.170
5.334 -4.580
s .n
o
Heig
ht
from
top
m
0.00
3.20
6.40
9.60
13.280
2.010 6.438
2.261 5.795
2.512 6.438
18.553
Com
pre
ssiv
e s
tress
in s
teel due t
o
Self w
t
Com
pre
ssiv
e s
tress
in s
teel due t
o
Lin
ing
wt
N/mm2 N/mm2
0.000 0.000
0.251 1.073
0.502 2.146
0.754 3.219
1.005 4.292
1.256 5.365
1.507 6.438
1.758 5.634
12.80
16.00
19.20
22.40
25.60
28.80
32.00
Leew
ard
sid
e c
om
pre
ssiv
e s
tress
in
steel due t
o (
Win
d +
Self w
t of
Chim
ney.)
N/mm2
0.000
1.144
3.175
6.087
9.876
14.536
20.060
20.271
25.759
25.957
31.406
Leew
ard
sid
e c
om
pre
ssiv
e s
tress
in
steel due t
o (
Tota
l dead load =
1.2
5*W
s) +
wt
of
linin
g +
Win
d
N/mm2
0.000
2.280
5.446
9.495
14.420
20.215
26.875
26.344
32.700
32.316
38.473
Win
dw
ard
sid
e t
ensi
le s
tress
in
steel due t
o (
Tota
l dead load =
1.2
5*W
s) +
wt
of
linin
g -
Win
d
N/mm2
0.000
0.495
0.102
-1.172
-3.323
-6.345
-10.230
-10.681
-14.799
-15.075
-19.316
14
18
21 3 4 5 6
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
Prep By : A B Quadri- Abq Consultants - 9959010210 - [email protected]/2 Royal Residency, Besides Amba talkies, Mehdipatnam , Hyderabad-500028-www.abqconsultants.com
35.355 -30.080
34.495 -28.968
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
-27.987
33.148 -27.119
37.562 -32.789
36.369 -31.345
33.898
32.630 -26.350
28.894 -26.382
28.826 -26.062
33.983 -30.969
-30.632
39.012 -35.495
38.907 -35.139
43.973 -39.954
39.464
38.967 -34.445
44.80
48.00
41.60
7.404
6.029 7.726
73.60
76.80
33.765
4.773 6.116
5.024 6.438
5.275 6.760
60.80
64.00
67.20
38.40
5.526 7.08270.40
2.512 6.438
2.763 5.902
3.014 6.438
3.266 5.979
3.517 6.438
3.768 6.036
4.019 6.438
4.270 5.473
4.522 5.795
51.20
54.40
57.60
80.00
32.00
35.20
5.778
6.280 8.048
31.406
31.589
36.998
37.164
-19.138
38.473
38.182
44.190
-19.316
-19.470
-23.777
-23.837
50.413
49.644
49.087
48.710
48.485
48.391
48.410
48.528
-17.886
-16.732
43.958
49.846
49.653
55.435
50.274
18
20
20
22
22
24
24
28
28
28
28
28
28
28
-28.17742.528
42.675
47.992
43.734
43.488
42.335
41.393
40.631
40.021
39.542
39.177
38.910
-35.193
Ok
28
28
-28.161
-32.511
-28.653
-27.520
-25.479
-23.651
-22.001
-20.504
21 3 4 5 6
Check total thickness of Chimney with corrosion allowance :
0
1
2
3
4
5
6
7
8
9
10
11
12
13
62.25 0.13860 568.20 728
s .n
o
Height from top
diameter of
chimney from
top
Total thickness of Steel
Plate with corrosion
allowance.
D/t ratio
Effective height for
axial stress--h1
ratio h1/D for axial stress
ratio h1/D for bending
stress = 0.5*h1/D
Allowable stress in
axial compression as per table
3 * kt
Allowable stress in
bending as per table 3
* kt
Section Modulus Z = 0.77 d2 t
Self wt Ws (total) from
top
Wt of Lining from top
m mm mm mm N/mm2 N/mm2 m3 Kn Kn
0.00 300014
214 Ok 0 0.000 0.000 0.00 0.00 0.09702 0 0
12800 4.267 2.133 54.13 54.13 0.09702 66.29 121
3.20 300014
214 Ok 6400 2.133 1.067 54.13 54.13 0.09702 33.15 61
9.60 300014
214 Ok 19200 6.400 3.200 54.13 54.13 0.09702 99.44 182
6.40 300014
214 Ok
12.80 300014
214 Ok 25600 8.533 4.267 54.13 54.13 0.09702 132.58 243
16.00 300014
214 Ok 32000 10.667 5.333 54.13 54.13 0.09702 165.73 303
300014
214 Ok 38400 12.800 6.400 54.13 54.13 0.09702 198.87 364
51200 17.067 8.533 57.84 57.84 0.11088 303.04 485
22.40 300016
188 Ok 44800 14.933 7.467 57.84 57.84 0.11088 265.16 425
19.20
60.55 0.12474 426.15 607
28.80 300018
167 Ok 57600 19.200 9.600 60.55 60.55 0.12474 383.54 546
25.60 300016
188 Ok
35.20 300020
150 Ok 70400 23.467 11.733 59.93 62.25 0.13860 520.85 667
32.00 300018
167 Ok 64000 21.333 10.667 60.29
41.60 300022
136 Ok 83200 27.733 13.867 56.32 62.95 0.15246 677.11 789
38.40 300020
150 Ok 76800 25.600 12.800 57.82
2214
15
16
17
18
19
20
21
22
23
24
25
Prep By : A B Quadri- Abq Consultants - 9959010210 - [email protected]/2 Royal Residency, Besides Amba talkies, Mehdipatnam , Hyderabad-500028-www.abqconsultants.com
2218
0.36398 1997.40 1828
48.00 300024
125 Ok 96000 32.000 16.000 51.67 62.50 0.16632 852.30 910
44.80 300022
136 Ok 89600 29.867 14.933 54.17 62.95 0.15246 729.19 850
51.20 300024
125 Ok 102400 34.133 17.067 49.58 62.50 0.16632 909.12 971
Ok 115200 36.145 18.072 47.65 62.50 0.21901 1267.68 1160
54.40 300028
107 Ok 108800 36.267 18.133 47.54 62.50 0.19404 1126.93 1032
48.98 62.92 0.28692 1612.18 1476
60.80 341828
122 Ok 121600 35.581 17.790 48.19 62.50 0.25182 1434.84 1313
57.60 318728
114
62.49
67.20 387828
139 Ok 134400 34.653 17.327 49.39 62.90 0.32431 1799.70 1647
64.00 364828
130 Ok 128000 35.088 17.544
73.60 433928
155 Ok 147200 33.923 16.962 49.24 61.81 0.40595 2205.29 2019
70.40 410928
147 Ok 140800 34.268 17.134 49.44
80.00 480028
171 Ok 160000 33.333 16.667 48.32 59.96 0.49674 2651.60 2427
76.80 457028
163 Ok 153600 33.613 16.807 48.84 60.95 0.45020 2423.35
0
1
2
3
4
5
6
7
8
9
10
11
N/mm2
0.00 0.000 0.000 0.000 0.000 0.000 0.000 0.000
3.20 0.251 0.460 0.382 -0.131 0.634 0.391 1.156
s .n
o
Height from top
Compressive stress in
steel due to Self wt (total).
Compressive stress in
steel due to Lining wt
tensile and compreeive stress due to wind.
Windward side tensile stress in
steel due to (Wind + Self
wt of Chimney.)
Leeward side
compressive stress in
steel due to (Wind + Self
wt of Chimney.)
Windward side tensile
stress in steel due to (Total dead
load = 1.25*Ws) + wt of lining -
Wind
Leeward side
compressive stress in
steel due to (Total dead
load = 1.25*Ws) + wt of lining
+ Wind
m N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2
12.80 1.005 1.840 3.802 -2.797 4.807 -0.707 6.898
16.00 1.256 2.299 5.691 -4.435 6.947 -1.822 9.561
6.40 0.502 0.920 1.145 -0.643 1.648 0.403 2.693
9.60 0.754 1.380 2.286 -1.532 3.039 0.036 4.608
25.60 2.010 3.219 11.875 -9.865 13.884 -6.144 17.606
28.80 2.261 3.219 13.164 -10.904 15.425 -7.119 19.210
19.20 1.507 2.759 7.951 -6.444 9.458 -3.308 12.594
22.40 1.758 2.817 9.256 -7.498 11.015 -4.242 14.271
32.00 2.512 3.577 16.052 -13.540 18.564 -9.336 22.769
35.20 2.763 3.541 17.295 -14.532 20.059 -10.300 24.291
7 8 19 10 11 12
12
13
14
15
16
17
18
19
20
21
22
23
24
25
Prep By : A B Quadri- Abq Consultants - 9959010210 - [email protected]/2 Royal Residency, Besides Amba talkies, Mehdipatnam , Hyderabad-500028-www.abqconsultants.com
38.40 3.014 3.863 20.390 -17.376 23.404 -12.759 28.021
41.60 3.266 3.805 21.571 -18.306 24.837 -13.685 29.458
51.20 4.019 4.292 29.315 -25.296 33.335 -19.999 38.632
54.40 4.270 3.909 28.188 -23.918 32.459 -18.941 37.435
44.80 3.517 4.097 24.826 -21.309 28.342 -16.332 33.319
48.00 3.768 4.024 25.938 -22.170 29.706 -17.204 34.672
70.40 5.526 5.059 24.639 -19.113 30.165 -12.672 36.606
57.60 4.522 4.139 27.833 -23.312 32.355 -18.043 37.624
60.80 4.773 4.369 26.830 -22.057 31.603 -16.495 37.165
64.00 5.024 4.599 25.978 -20.954 31.002 -15.099 36.857
67.20 5.275 4.829 25.254 -19.979 30.529 -13.831 36.677
73.60 5.778 5.289 24.118 -18.340 29.895 -11.607 36.628
29.587 -9.708 36.905
29.706 -10.622 36.732
80.00 6.280 5.749 23.307 -17.027
76.80 6.029 5.519 23.677 -17.648
7 8 19 10 11 12
10 :- Design of Anchor Bolts (Holding Down Bolts) :- mm dia
Maximum tensile force per unit length of circumferance =
* = n/mm
Provide M dia Anchor bolt
Area at root of threads = mm2
Strength of Anchor Bolt = * = Kn
Spacing of Bolt = * =
d2 =
Provide Anchor Bolt at mm spacing Nos of Anchor Bolts Required =
Spacing of Bolt provided =
9 :- Design of Base Plate :-
Maximum stress on Chimney base plate due to Load case 1 to 12 =
* = n/mm
=
= = mm 18 dia
Allowable stress in bending of Base Plate = 0.75 fy A A
= * = n/mm2
Moment on wide plate = * * *
thk base pl
= Kn.m
Z of plate = *
.: t = * 6 * ½ = thickness of base plate.
44
45
N/mm2
Width of base Plate required
[ 10511188 ]188
290
0.75 250 187.5
4.00
188 mm 4.00 188 290
Allowable Bearing Stress for Steel on Concrete
6
Oknos
44
1186
1186 120
1000
142.32
142.32 1000
738
193 mm
Allowable Stress in Anchor bolt = 120 N/mm2
190
Ok
mm
26.350 28.0 738 Ok
84
188
5023 mm
mm
84 nos
188 mm
@
44
290
6000000
10.511
188 t^2
48.528 28.0 1359 Ok
1359 340
4.00
Ok
*
= Adopt t =
9 :- Design of Vertical Stiffner Plate :- mm
Axial load on stiffner = Tensile load on one bolt = Fa =
Effective length of stiffner = * =
Width of stiffner =
Net thickness of stiffner =
= mm L/r = = fcc = = *
Allowable stress in compression σac = =
Allowable Load = σac x A = * * = kn kn
.: Provide Vertical stiffner Plate = thick
18 thk 45
thk
Prep By : A B Quadri- Abq Consultants - 9959010210 - [email protected]/2 Royal Residency, Besides Amba talkies, Mehdipatnam , Hyderabad-500028-www.abqconsultants.com
200000
61.71 mpa
61.71
122.687 π² E
(l/r)²
9.870
15052
mpa
3.464 425
290 12 215 Ok>= 142
340
mm 45 mm
[ 188 187.50 ] Sect A-A
12 mm
Assume thickness of stiffner , including external corrosion allowance =
mm
18 290 mm
4250.85 500
Ok
3.464
131
mm
142.32 Kn
Ok42.31
18 mm
r
10 :- Deflection of Chimney :-
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15 Ok
0.00E+00
1.27E-09
3.82E-09
7.62E-09
1.27E-08
1.90E-08
2.65E-08
check less than
H/200
9.88E-05
1.20E-04
1.12E+01
6
6
6
3.20
22.40 30008
25.60 30008
28.80 300010
M/EI
1/mm
3000
12.80 3000
19.20
6
16.00 30006
Ok
Ok
Ok
Ok
30006
6.40 30006
9.60
143000
3000
s .n
o
Height from top
diameter of
chimney from
top
Assumed thickness of Steel
Plate without
corrosion
m mm mm m4
Moment of Inertia I
(m4)
0.16632
Area M/EI
mm
0.00E+00
2.04E-06
8.15E-06
1.83E-05
3.25E-05
5.06E-05
7.28E-05
Wind Moment at bottom of
each segment.
Kn.m
0
37
111
222
369
552
771
1026
1317
0.00
Ok
35.20 300012
38.40 300012
41.60 300014
44.80
48.00 300016
32.00 300010
1.31E+01
9.41E+00
3000
Moment of (Area M/EI)
from top
mm2
0.00E+00
4.35E-03
3.91E-02
1.46E-01
3.64E-01
7.29E-01
1.28E+00
2.06E+00
2.87E+00
4.94E-08
5.35E-08
6.41E-08
6.80E-08
7.91E-08
2.59E-04
2.83E-04
1642
2002
2397
2826
3289
0.18711
0.18711
0.20790
0.20790
0.22869
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
3785
4314
0.22869
0.24948
8.28E-08
9.43E-08
233
218
204
189
174
160
146
132
118
105
92
80
69
58
48
39
1.42E-04
1.65E-04
1.88E-04
2.11E-04
2.35E-04
3.53E-08
3.96E-08
0.14553
0.14553
0.14553
0.14553
0.14553
0.14553
0.14553
0.16632
deflect
ion
mm
height to
deflection ratio (h/δ)
344
352
362
373
386
400
417
437
461
488
521
559
607
664
736
827
mm
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
3.87E+00
5.00E+00
6.32E+00
7.77E+00
Ok
Ok
Ok
Ok
Ok
Ok
30.00
40.00
50.00
60.00
70.00
80.00
90.00
De
fle
ctio
nD
iag
ram
15
16
17
18
19
20
21
22
23
24
25
Maximum deflection at top = mm
Height to deflection ratio (h/δ) at top = = =
Prep By : A B Quadri- Abq Consultants - 9959010210 - [email protected]/2 Royal Residency, Besides Amba talkies, Mehdipatnam , Hyderabad-500028-www.abqconsultants.com
20
Ok
3.32E-04 1.75E+01
1.92E+01
1.91E+01
410920
64.00 3648
57.60
20
76.80 457020
80.00 480020
54.40 Ok
16
1.65E+01
1.58E+01
3187
67.20 3878
70.40
1.52E+01
73.60 433920
48.00 3000
51.20 3000
20
60.80 341820
0.74776
0.88074
1.31E+01
7.82E-08
300020
1.52E+01
1.47E+01
233
3.43E-04
3.22E-04
2.93E-04
2.64E-04
2.39E-04
2.19E-04
2.02E-04
1.87E-04
2.83E-04
3.07E-04
1.83E+01
1.73E+01
Ok
Ok
4314
4876
7.13E-08
6.55E-08
6.05E-08
5.63E-08
0.24948
0.29106
0.34902
0.24948
0.43031
0.52334
0.62889
1.02862
1.19218
Ok
Ok
Ok
Ok
Ok
Ok
9.43E-08
9.77E-08
1.10E-07
1.05E-07
9.68E-08
8.66E-08
39
Ok Ok
5
3
1
0
0
827
944
1095
1295
1562
1935
2491
3413
Ok
10703
0
5470
6096
6756
7454
8190
8968
9790
10659
11577
5248
31
23
17
12
8
Ok
Ok
Ok
Ok
Ok
Ok
Ok
Ok
80000
233
344 <= 400 mmh
200
Ok
0.00
10.00
20.00
30.00
40.00
50.00
60.00
70.00
80.00
90.00
0 100 200 300
De
fle
ctio
nD
iag
ram
10 :- Design of Chimney Foundation :-
Loads on Foundation :-
Self Weight of Chimney without corrosion allowance = 100As
= bd
= 15 20 25 30 35 40
0.25 0.22 0.22 0.23 0.23 0.23 0.23
0.50 0.29 0.30 0.31 0.31 0.31 0.32
0.75 0.34 0.35 0.36 0.37 0.37 0.38
1.00 0.37 0.39 0.40 0.41 0.42 0.42
1.25 0.40 0.42 0.44 0.45 0.45 0.46
1.50 0.42 0.45 0.46 0.48 0.49 0.49
= 1.75 0.44 0.47 0.49 0.50 0.52 0.52
= 2.00 0.44 0.49 0.51 0.53 0.54 0.55
2.25 0.44 0.51 0.53 0.55 0.56 0.57
2.50 0.44 0.51 0.55 0.57 0.58 0.60
2.75 0.44 0.51 0.56 0.58 0.60 0.62
3.00 0.440.51 0.57 0.60 0.62 0.63
D =
T =
=
Area = =
9.00 10.00
Allowable compressive stress (Bending) N/mm2 5.00 7.00 8.50 10.00 11.50 13.00
Allowable tebsile stress (Direct) N/mm2 -3.60 -4.00 -4.40
Moment at foundation top due to wind load
Shear at foundation top due to wind load 287 Kn
Sw1
Sw2
SL
Grade of Steel (N/mm2)
8.00
15MGrade of conc (N/mm2)
140 230
250
7.18
Allowable compressive stress (Direct) N/mm2 4.00 5.00 6.00
Kn.m
-2.00 -2.80 -3.20
9.33 8.11
415
Allowable tebsile stress
N/mm2
kn/m3
530 Kn
1894 Kn
2652 Kn
2427 Kn
Weight of the (platform+ access ladder+ helical strake+ rain cap + etc) is assumed to be 20% of the self weight of chimney shell without corrosion allowance
Weight of the (platform+ access ladder+ helical strake+ rain cap + etc) is assumed to be 20% of the self weight of chimney shell with corrosion allowance
20 25 30 35 40
modular ratio m 18.67 13.33 10.98
Adopt the diameter of Chimney foundation
m²
SBC of Soil At foundation Base 300 kn/m²
Depth of foundation from NGL 6.00 m
Concrete density25
Mwl1
Swl1
Self Weight of Chimney with corrosion allowance
Self Weight of Chimney Lining.
Swp1 = 379 Kn
Swp2 =
Moment due to wind shear at foundation base Mswl1 = 1721 Kn.m
12.00
π D²
m
113.10
11577
1450 mm
Self wt of Footing Swf1 7687 kn
Adopt the thickness of Chimney foundation
Ok
Permissible Shear Stress in Concrete Tc
N/mm2 for grade of concrete
Ok
Load Combinations Reference: clauses 6.5, IS 6533(Part-2):1989
(a) Dead load+ Wind load = =
(b) Dead load+ Load due to lining+ Imposed load on service platforms + Wind load
Prep By : A B Quadri- Abq Consultants - 9959010210 - [email protected]/2 Royal Residency, Besides Amba talkies, Mehdipatnam , Hyderabad-500028-www.abqconsultants.com
Dl+Wl
12387 13299 187.91
Dl+Wl
13296 13299
31.13 1.074 5.588 OkSw1+swp1+SL+swf1+Mwl1+Mswl1
3
Dl+Wl
10338 13299 169.80 13.02
DL (Axial)
1
2
39.17Sw2+swp2+SL+swf1+Mwl1+Mswl1
Kn
Sw2+swf1+Mwl1+Mswl1
4
s.no
Dl+Wl
kn/m2 kn/m2
195.95 1.000 5.999 Ok
Sw1+swf1+Mwl1+Mswl1
9581 13299 163.10 6.32 1.388 4.322 Ok
4
π D²
π D³ 169.65
Kn.m
Load caseF.S due to
over turning
m
e = (M/P) eccentricity < D/8, no
uplift checkDL/A - MWL/ZDL/A + MWL/ZWL (Moment)
m²
32
Z
1.286 4.664 Ok
e
P
Data FFLH
Soil filling inside
Actual Loading Pattern.Actual Loading Pattern.Actual Loading Pattern.Actual Loading Pattern.
σ = P' ±
A
Depth of Footing T = 1450 mm
6000
Totd
Outer dia of chimney base plate d = 5.323 m
1450
T
Dia of Footing OD = 12.00 m
A = 200 mm
Depth of Soil D = 4550
Concrete Grade fc' = 25 N/mm2
200
AReinforcement Steel Grade fy = 415 N/mm2
S.B.C of Soil Qs = 200 Kn/m2
4550
D
Design of Footing slab
Level of footing below ground
Totd = 6000 mm
FGL
mm
12000
Reinforcement cover c = 75 mm
OD
OD
M'
Zxx
5323
d
12000
12000
Footing Reinforcement dia Φ = 20 18 mm
Assume initially of mm Φ bars nos
+ mm Φ bars = mm2 Spacing between bars at
Φ = º = radians end. =
= = mm
= = mm
= mm Length of segment 'PQ'
= mm Length of segment 'RS'
Net Uniform pressure Main Reinforcement
=
=
=
Prep By : A B Quadri- Abq Consultants - 9959010210 - [email protected]/2 Royal Residency, Besides Amba talkies, Mehdipatnam , Hyderabad-500028-www.abqconsultants.com
569
2.40 0.0419
Radius of Chimney ro 2662
Radius of Foundation fro 6000
Bar Spacing at ro 111
Area of Segment 'PQRS' 0.606 m2
= 1.884 mfrom 'PQ'
fig 9
Area covered by
one unit of main
reinforcement.
spaced radially along the circumferance.
37699
150
251
300
=
<= Ok
1 Layer 20 150
18 As
Bar Spacing at fro 251
= 73.0 Kn / m2
= 78.4 Kn / m2
= 34.8 Kn / m2
CG of Segment 'PQRS'
Width of segment RS
Width of segment PQ
251 mm
111 mm
under area 'PQRS'
Pressure due to
Moment at 'RS'
Pressure due to
Moment at 'PQ' ro
fro
Φ
Critical Section for
Moment
Footing Outer Dia
Chimney Outer dia of base plate
A A
P
RRRR
Q
Line of Punching Shear
Line of Shear
a1
a2
b2
b1
rs
rp
SSSS
Section A - A
Shear Stirrups
Main Radial reinforcement Circullar reinf
Φ nos 16 Φ @ c/c
cover
.: = + = =
.: k = * = =
* + =
j = 1 - k = 1 - = =
3 =
R = 1 j k = 1 * * * =
2 2
Hence d = = * =
* R * = m3
+ m3
.: adopt T = cover = d = - + m3
.: d = effective depth + m3
As = = = = m3
Fyall * j * d * *
Ok
Not Required
2662 2500 838
Straight portion Sloping portion
fig 10
Moment at 'PQ' Mf
1.52
r
415
10.98
105.72
1450
900
20 150 200
688 75
1375
6000
N/mm2
25 N/mm2
8.5 N/mm2
Mf 152.29 1000000 1110
b 111 1.109
1450 mm 75 mm 1450 75
1375 mm Ok
M 152293825
m
533 mm2
29.39
230 0.904 1375
230 N/mm2
16
10.98 8.5 0.289
10.98 8.5 230
0.289 0.904
3
fc'all 8.5 0.904 0.289 1.109
critical punching shear section
critical shear Section
122.90
Φ top radial
reinforcement
46.04
101.79
53.92
307.46
volume of footing
Wt of Footing
mm
152.29 Kn .m
fyall
fy
fc'
fc'all
1
C / L of foundation
C / L
Fyall * j * d * *
= .: Adopt As = = kn
.: Φ + Φ = Π * ( ² + ² )
4 = kn
=
Φ @ c/c = * = %
*
Check Punching shear at ro + d/2 from the c/L
r = d = r + d =
2 2
Φ = º = radians
= = mm
= = mm
= mm
= mm
=
.: F = + =
= √√√√ = * √√√√ =
.: Depth required for punching shear do
√√√√ * *
= <
Prep By : A B Quadri- Abq Consultants - 9959010210 - [email protected]/2 Royal Residency, Besides Amba talkies, Mehdipatnam , Hyderabad-500028-www.abqconsultants.com
2662 mm 687.5 mm 3349
p%Provide 16 200
mm
567 mm2 ok
2.40 0.0419
1375
569 100 0.371
18 AΦ 20 18
dia bars.
mm2 >
25 0.8 N/mm2
Bar Spacing at rps 140 Length of segment 'a1a2'
Bar Spacing at fro 251 Length of segment 'RS'
= 73.0 Kn / m2Area of Segment 'PQa1a2' 0.519052 m2
CG of Segment 'PQa1a2'= 1.451 m
=
Kn / m2
60.59 8.99
Main radial reinforcement 569
Allowable Punching Shear stress
Punching Shear at 'a1a2'
distribution steel 111
Provide 20
1
1375 OK
= 43.8
230 0.904 1375
567 mm 2 >= 533 mm2 567 mm2
0.16 fck 0.16
78.4 Kn / m2from 'a1a2'
Radius of Punching shear rps 3349
Radius of Foundation fro 6000
layer of
Net Uniform pressure
under area 'PQRS'
Pressure due to
Moment at 'RS'
Pressure due to
Moment at 'PQ'
Minimum As required
Punching Shear :Punching Shear :Punching Shear :Punching Shear :
mm provided
= =69574
Wt of Footing
7687
F
0.16 fck 140 0.8 140
620
Net Wt of Footing
5044
69.57 Kn
C / L of foundation
C / L
Check shear at r + d from the c/L, End of Straight portion,
and at three points at sloping portion.
20 + 18 20 + 10 20 + 14 20 + 16 20 + 14 20 + 14
Shear :Shear :Shear :Shear :
distance from c/L mm 2662 3349 4037 5162 5581 6000
Reinforcement Spacing mm 110 140 168 216 232 250
Effective depth mm 1375 1375 1375 1192 1008 825
Bar dia mm
As mm2 569 393 468 515 468 468
p% 0.3760 0.2040 0.2026 0.2002 0.2001 0.2270
Ok Ok Ok Ok Ok Ok
Net Uniform pressure kn/m2 73.0 73.0 73.0 73.0 73.0 73.0
Pressure due to moment @ rs kn/m2 78.4 78.4 78.4 78.4 78.4 78.4
Pressure due to moment at section kn/m2 34.8 43.8 52.7 67.4 72.9 78.4
Area of Segment 'PQxx' m2 0.606 0.519 0.413 0.196 0.102 0.000
CG of Segment 'PQxx' m 1.89 1.45 1.05 0.43 0.21 0.00
M actual / bar Kn.m 153 104 61 12 3 0
M allowable / bar Kn.m 163 112 134 128 98 80
Ok Ok Ok Ok Ok Ok
p% for Shear 0.25 0.25 0.25 0.25 0.25 0.25
Shear Stress tc N/mm2 0.23 0.23 0.23
Shear allowable Kn 53 59 54
Shear actual Kn 52 28 15
mm 0 0 0
.: Provided spacing = mm 0 0 0
Shear Reinf Not Reqd Not Reqd Not Reqd
Shear - Vs per main bar Kn 1 1 1
Shear - MS bar dia fyall 230 1 1 1
spacing mm 0 0 0
Minimum shear s = 2.5Asvfy/b
Prep By : A B Quadri- Abq Consultants - 9959010210 - [email protected]/2 Royal Residency, Besides Amba talkies, Mehdipatnam , Hyderabad-500028-www.abqconsultants.com
.: Provided spacing = mm 0 0 0