The design sheet deals with analysis & design of RCC Overhead tank with staging of columns or RCC shaft
47
DESIGN OF OVERHEAD TANK AT NAI BASTI, JAMMU 1.00 INTRODUCTION The following sheets pertain to the design of 2 lakh gallon capacity RCC Ci The tank is proposed to be built at east of Jammu city, at Nai Basti under t It is basically a circular intze type tank with RCC shaft supporting the tank on open foundation. 2.00 REFERENCES IS 3370 -2009 Code of Practice for Concrete structures for the storage o Part 1 : General Requirements Part 2 : Reinforced Concrete Structures IS 11682 -1985 Criteria for design of RCC staging for overhead water tank IS 875 : 1987 Code of Practice for Design Loads (other than earthquake Part 2 : Imposed Loads Part 3 : Wind Loads IS 1893 : 1984 Criteria for earthquake resistant design of structures IS 11089: 1984 Code of Practice for Design & Construction of Ring Found Kuang-han Chu & Omar.F.Afandi : Analysis of circular & annular slabs for ch 3.00 PRINCIPAL PARAMETERS General Capacity of tank proposed V = 909 Free board = 0.60 m SBC of soil = 15.00 Density of water = 9.81 Density of concrete = 24.00 Density of soil = 19.00 Type of Foundation = Solid Circular Raft Fou Depth of foundation below ground level = 1.50 m Material Properties Grade of Concrete tank = M30 shaft = M30 foundation = M30 Grade of Reinforcement = Fe500 Top Dome Inner Radius = 6.00 m Rise = 2.00 m Thickness = 0.10 m Ring beam below dome m 3 h b T/m 2 kN/m 3 kN/m 3 kN/m 3 r 1 h 1 t 1
Transcript
DESIGN OF OVERHEAD TANK AT NAI BASTI, JAMMU
1.00 INTRODUCTIONThe following sheets pertain to the design of 2 lakh gallon capacity RCC Circular Overhead Tank. The tank is proposed to be built at east of Jammu city, at Nai Basti under the water supply project. It is basically a circular intze type tank with RCC shaft supporting the tank and the shaft is rested on open foundation.
2.00 REFERENCESIS 3370 -2009 Code of Practice for Concrete structures for the storage of liquids
Part 1 : General RequirementsPart 2 : Reinforced Concrete Structures
IS 11682 -1985 Criteria for design of RCC staging for overhead water tanksIS 875 : 1987 Code of Practice for Design Loads (other than earthquake) for buildings & structures
Part 2 : Imposed LoadsPart 3 : Wind Loads
IS 1893 : 1984 Criteria for earthquake resistant design of structuresIS 11089: 1984 Code of Practice for Design & Construction of Ring FoundationKuang-han Chu & Omar.F.Afandi : Analysis of circular & annular slabs for chimney foundations
3.00 PRINCIPAL PARAMETERS
General
Capacity of tank proposed V = 909
Free board = 0.60 m
SBC of soil = 15.00
Density of water = 9.81
Density of concrete = 24.00
Density of soil = 19.00Type of Foundation = Solid Circular Raft FoundationDepth of foundation below ground level = 1.50 m
Material PropertiesGrade of Concrete tank = M30
shaft = M30foundation = M30
Grade of Reinforcement = Fe500
Top Dome
Inner Radius = 6.00 m
Rise = 2.00 m
Thickness = 0.10 m
Ring beam below dome
m3
hb
T/m2
kN/m3
kN/m3
kN/m3
r1
h1
t1
Depth = 400 mmWidth = 400 mm
Bottom Dome
Inner Radius = 4.00 m
Rise = 1.60 m
Thickness = 0.20 m
Cylindrical Tank wall
Inner Radius = 6.00 m
Thickness = 0.40 mHeight h = 6.30 m
Ring beam below wallDepth = 600 mmWidth = 800 mm
Conical Shell below wallThickness = 0.60 m
Extent of shell = 4.00 m
Ring beam below bottom domeDepth = 600 mmWidth = 800 mm
RCC ShaftDiameter = 8.00 mThickness = 0.20 mHeight of shaft = 20.00 m
Annular Circular FoundationWidth of foundation = 3.00 mThk. of footing = 0.60 m
Design Parameters ( IS 3370-2009 Part II)
Clear cover to reinforcement = 40 mm
Concrete stresses M30Direct tensile stress in concrete = 1.5Bending Tensile stress in concrete = 2.0Direct comp. stress in concrete = 8.0Comp. stress in bending in concrete = 10.0
Hoop stress in concrete = T = 370.82 xAc + (m-1) As 400000 +
= 0.87
> 1.50
Distribution steel = 0.24 % = 960.00
Ast provided = T12 @ 200 mm c/c = 565.49
Volume of wall = x 6.20 x
= 98.17
Weight of wall = 2356.04 kN
T cos .D
mm2
N/mm2
N/mm2
2m3
mm2
mm2
N/mm2
N/mm2
mm2
mm2
2
m3
8.00 DESIGN OF RING BEAM AT BOTTOM OF WALL
Length of beam = x 6.40= 40.21 m
Load of dome on beam = 301.59 = 7.50 kN/m40.21
Load of top ring beam = 149.59 = 3.72 kN/m40.21
Load of wall on beam = 2356.04 = 58.59 kN/m40.21
Self weight of beam = 0.60 x 0.80 x= 11.52 kN/m
Total vertical load on beamV1 = 7.50 + 3.72 +
81.33 kN/m
=
Horz.force on beam due to V1 H = =
Hoop tension due to above load , Hv = H.D /2= 40.67 x
Hoop tension due to water Hw =
Hw = 61.80 x= 148.33 kN
Total Hoop Tension = Hv + Hw = 392.32 kN
Steel area reqd. = 392.32 x 1000 =130
Provide 8 No. bars 25 mm bars ( = 3926.99
Weight of beam = 11.52 x 40.21 =
Hoop stress in concrete = T = 392.32 xAc + (m-1) As 480000 +
= 0.72
2
Angle between wall & conical shell, = tan-1 h3
r1 - r3
V1 cot
wh x d x D/2
mm2
N/mm2
< 1.50
Min. shear steel, Asv = 0.4b.d = 1476.92fy
Provide 4 L stirrups 10 mm @ 200 mm c/c
Shear Steel provided = 1570.80
N/mm2
mm2
mm2
9.00 DESIGN OF CONICAL DOME
The conical dome shall be designed fora) Hoop Tensionb) Meridonial thrust
6.30 10.30
2.00
Area of water on conical slab = (6.3 + 10.3) x2
Average radius of conical shell = (6 + 4 ) =2
Weight of water on conical slab, Ww = 16.60= 5115.96 kN
Lever arm, x = 0.92 m
Weight of conical slab, Ws = 4.57= 2313.02 kN
Total load at base of conical slab = 3270.47 += 10699.45 kN
Load per unit length V2 = 10699.455.000
a) Meridional Thrust T == 340.57 x
Meridional Stress = 380.77 x 1000 =1000.00 x 600
>
b) Hoop tensionThe hoop tension will be maximum at the top of the conical slab as the diameter is max.
x 2
x
x 2
V2 cosec.
at this location.
Hoop tension H = ( + ) D/2
Average height of water = (6.3 + 10.3 = 8.30 m2
Water pressure, p = 8.30 x 9.81 =
Conical slab weight, q = 0.600 x 24.00 =
= 63.43
Hence, H = ( 81.42 x 1.12 + 14.40 x= 589.40 kN
Hoop stress in concrete = T = 589.40 xAc + (m-1) As 600000 +
= 0.92
> 1.50
Ast reqd. = 589.40 x 1000 = 4533.86(both faces) 130
Ast provided = T25 @ 200 mm c/c = 2454.37
Distribution steel reqd. = 0.24 % = 1440.00
Ast provided = T20 @ 200 mm c/c = 1570.80
c.g of the conical slab from base =
= 1.74 m
p cosec. q cot.
Angle , o
N/mm2
N/mm2
N/mm2
mm2
mm2
mm2
(r 2 2 + 2r 2.r 3 + 3r 3
2) h 3 4 (r2
2 + r2.r3 + r32)
### DESIGN OF BOTTOM DOME
Total Load on dome, w = 5226.59
From geometry of dome , we have
1.60 4.00 2
R = 5.80 m
= D = 4.00 = 0.68972R 5.80
= 43.60
= 0.724
Water Load on dome 4.00 10.30 -
= 4946.71
Area of dome surface = x 5.80 x
Self weight of dome = 58.31 x 0.20 x
Total load intensity on dome = 4946.71 + 4.80 =58.31
a) Hoop stress at springing level = 1 =(compressive) t
=
=
>
Hence, providing minimum steel of 0.24% as per IS3370- 2009 Part II, we have
Ast reqd. = 0.24 % = 480.00
Ast provided = T12 @ 200 mm c/c = 565.49
b) Meridional thrust at springing level, T = wR =
=
Meridional compresssive stress = 301.54 =
0.20 =
<
kN/m2
R2 - (R - )2 =
sin
o
cos
= x 2 x
kN
2
wR cos -1 + cos
mm2
mm2
1 + cos
Hence, providing minimum steel of 0.24% as per IS3370- 2009 Part II, we have
c.g of this load = where
R == 300.00
63.20= 4.75 m above the centre of the sphere
3 (2R - h1)2 h1=
4 (3R - h1)
11.0 DESIGN OF RING BEAM AT JUNCTION OF BOTTOM DOME & SHAFT WALL
Weight of water = 920.65 xWeight of top dome & ring beam = 301.59 +Weight of side wall & ring beam = 2356.04 +Weight of conical wall & bottom dome = 2313.02 +Self wt. of beam x 0.6 x 0.8 x 24Total Load on beam
Thrust intensity of T1 = 10699.45 = 425.72 kN/m25.13
Thrust from bottom dome = 4946.71 + 279.88 =
Thrust intensity of T2 = 4946.71 = 196.82 kN/m25.13
Hoop tension on ring beam = - =
Steel area reqd. = 258.91 x 1000 =130
Provide 8 No. bars 20 mm bars ( = 2513.27
Hoop stress in concrete = T = 258.91 xAc + (m-1) As 480000 +
= 0.52
> 1.50
Direct stress due to vertical load = 605.32 x600 x
= 1.26
< 8.00
=2 x
T1 cos T2 cos
mm2
N/mm2
N/mm2
N/mm2
N/mm2
12.0 DESIGN OF ANNULAR R.C.C SHAFT
Grade of Concrete = M30
AS per IS 11682:1985, Min. thickness of shaft < where D =
120 =< 166.67 mm
Hence, provide thk t = 200.00 mm
Opening size at base = 1.00 m x 2.10m
From sketch, = 0.125
Wind Pressure considered
w = 1.50
Volume of shaft = 20.00 x 4.100 x
Slf Weight of shaft = 103.04 x 24.00 =
Summary of Forces on Shaft
ComponentWeight Area exposed
(kN) A (sqm.)Top dome 301.59 125.66Ring beam below top dome 149.59 5.12Side wall 2356.04 80.64Ring beam below wall 463.25 8.16Conical slab 2313.02 44.80Bottom dome 279.88Ring beam below bot. dome 318.48 5.76RCC Annular shaft 2473.06 168.00Total self weight of tank W = 8654.91 kN
Weight of water 9031.54 kN
Wind Load Moment, Mw = = 12815.31 kNm
Ovalising Moment , Mo = (Refer IS 11682:1985)where r = mean radius of shaft =and p = wind pressure in Mpa
Hence, Mo = 8.32 kNm/m
150 + (D-6000)
kN/m2
x 2
F.y
3.3pr2
From IS 11682, we have
Max. compressive stress in concrete
Parameters Empty Tank Full TankW 8654.91 17686.45e (M/P) 1.48 0.72e/r 0.36 0.18
As per IS11682, Cl.8.2.2,Provide vertical steel min. = 0.25 % distributed in both faces
= 500.00
Ast provided each face = T10 @ 200 mm c/c =
Provide hoop steel min. = 0.20 % distributed in both faces
= 400.00
Ast provided each face = T10 @ 200 mm c/c =
mm2
mm2
12.1 Seismic Analysis of shaft (As per provisions of IS1893:1984)Since Jammu is in Zone-IV, we have
Mod. of elasticity of concrete Ec = 5000 fck =Zone factor = 1.0
Moment of Inertia = =Seismic Zone Factor Fo = 0.25
Importance Factor I = 1.5
Type of soil = Medium
Parameters EmptyWeight considered (kN) 7006.21
Deflection (m) 0.020Time Period T (sec.) 0.28For 5% damping Sa/g 0.20
Horizontal Seismic Coefficient 0.075Base shear, H (kNm) 525.47Base Moment, M (kNm) 10509.31e/r 0.30Max. compressive stress in conc. (Mpa) 3.03Permissible stress (Mpa) 10.66
OK
MI (2r)3.t /8
=Wl3/3EI2 / g
.I.Fo.Sa/g
14.0 DESIGN OF CIRCULAR RAFT FOUNDATION
The following sheets pertain to the design of 2 lakh gallon capacity RCC Circular Overhead Tank. The tank is proposed to be built at east of Jammu city, at Nai Basti under the water supply project. It is basically a circular intze type tank with RCC shaft supporting the tank and the shaft is rested
Code of Practice for Concrete structures for the storage of liquids
Criteria for design of RCC staging for overhead water tanksCode of Practice for Design Loads (other than earthquake) for buildings & structures
Code of Practice for Design & Construction of Ring FoundationKuang-han Chu & Omar.F.Afandi : Analysis of circular & annular slabs for chimney foundations
Solid Circular Raft Foundation
h
h1
r1
r2
h2 h3
M251.52.06.08.5
IS 456 :2000230190
r3
M2510.98
0.29
0.90
1.11
608.00 - 80.90
>V, Hence OK
( h - hb ) + 2 (r22 + r2.r3 + r3
2) h3 - (3r32 + h2
2) h2
0.742.00
125.66
2.40 125.66
31.36 x 0.240.10
76.65
0.08
8.00OK
Hence, providing minimum steel of 0.24% as per IS3370- 2009 Part II, we have
OK
31.361.80
17.42
174.20
0.17
8.00OK
Hence, providing minimum steel of 0.24% as per IS3370- 2009 Part II, we have
kN/m2
m2
kN/m2
kN/m2
N/mm2
N/mm2
kN/m
kN/m2
N/mm2
N/mm2
OK
Surface Area of dome x Intensity of loading
2.00 x 2.40
2.00 m
10.00 m
above the centre of the sphere
0.800 x 6.00
643.19
) OK
10005655
OK
0.40 x 0.40
6.3
OK 61.80
100026180
OK
each face OK
0.40 x 6.30
mm2
kN/m2
24
58.59 + 11.52
63.43
81.33 = 40.67 kN/m2.00
6.00 = 243.99 kN
where d = depth of beam
= water load
0.40 x 6.00
3017.82
) OK
463.25 kN
100065450
o
wh
mm2
OK
/m
/m OK
2.00 = 16.60
5.000 m
x 5.000 x 9.81
x 11.200 x 0.60 x 24
5115.96 + 2313.02
= 340.57 kN/m
1.12 = 380.77 kN
0.63
8.00OK
The hoop tension will be maximum at the top of the conical slab as the diameter is max.
m2
N/mm2
N/mm2
81.42
14.40
0.50 ) x 6.00
100040906
OK
each face OK
OK
kN/m2
kN/m2
+ 3r 3 2) h 3
1.60 3 x5.8-1.6) 9.813
1.60 = 58.31
24.00 = 279.88
89.64
519.90 x 0.1440.20
374.69
0.37
8.00 OK
Hence, providing minimum steel of 0.24% as per IS3370- 2009 Part II, we have
OK
519.901.724
301.54
1507.71
1.51
8.00 OK
2 (
m2
kN
kN/m2
kN/m2
N/mm2
N/mm2
kN/m
kN/m2
N/mm2
N/mm2
Hence, providing minimum steel of 0.24% as per IS3370- 2009 Part II, we have
1.60 m
5.80 m
above the centre of the sphere
DESIGN OF RING BEAM AT JUNCTION OF BOTTOM DOME & SHAFT WALL
Sl. Items of Concrete Measurement 1.00 Top Dome x 10.00 x 2.00 x 0.10
x 10.00 x 2.00
2.00 Top dome beam x 6.20 x 0.40 x 0.40x 6.20 x 1.20
3.00 Side wall x 6.20 x 0.40 x 6.30x 6.20 x 12.60
4.00 Beam below wall x 6.40 x 0.60 x 0.80x 6.40 x 2.00
5.00 Conical slab x 4.57 x 0.60 x 11.20 x 4.57 x 11.20
6.00 Bottom dome x 5.80 x 1.60 x 0.20x 5.80 x 1.60
7.00 Bottom dome beam x 4.40 x 0.60 x 0.80x 4.40 x 2.00
8.00 Shaft x 4.10 x 0.20 x 20.00x 4.10 x 40.00
8.10 Openings ventilators 6 0.50 x 0.50door 1 2.10 x 1.50
9.00 Type of Foundation Pile Foundation
Annular Footing
kicker x 4.10 x 0.40 x 0.60x 4.10 x 0.60
stem x 4.10 x 0.60 x 0.30x 4.10 x 0.30
base x 4.10 x 3.00 x 0.60x 4.10 x 0.60
OR
Pile FoundationDia = 600 x 0.090 x 25.00 x 40
Length = 25000No. = 40
Capacity = 125MT
22
22
22
22
22
22
22
222222
Pile capWidth = 3000 x 4.10 x 3.00 x 1.00Depth = 1000 x 4.10 x 1.00
OR
Solid Circular Footing x 7.85 x 7.85 x 1.00x 7.85 x 1.00
10.00 Walkway10.10 Around tank 1.00 m wide x 6.90 x 1.00 x 0.12
( 2 Nos.) 0.12 m thk x 6.90 x 1.0010.20 Landings 1.00 m wide 9 x 1.00 x 1.00 x 0.12
0.12 m thk 9 x 1.00 x 1.001.50 m wide 1 x 1.50 x 1.50 x 0.15
0.15 m thk 1 x 1.50 x 1.505.00 m wide 1 x 5.00 x 0.75 x 0.35
0.35 m thk 1 x 5.00 x 5.001.90 m wide 1 x 1.90 x 1.00 x 0.15
0.15 m thk 1 x 1.90 x 1.900.50 m wide 1 x 0.50 x 1.00 x 0.15
0.15 m thk 1 x 0.50 x 0.50
11.00 Inner circular partition wall x 5.80 x 0.20 x 6.30(optional) x 5.80 x 12.60
12.00 M.S Ladder with railing
13.00 Additional railing on landings
14.00 Aluminium Ladder inside tank 2 x 8.00
15.00 Excavation footings x 5.60 x 5.60 x 1.50pilecap x 4.10 x 4.10 x 1.10
16.00 PCC footing x 4.10 x 3.20 x 0.10pilecap x 4.10 x 3.30 x 0.10inside shaft x 16.00 x 0.15
17.00 Painting 17.10 walls inside x 6.00 x 6.30
outside x 6.40 x 6.3017.20 conical inside x 5.00 x 4.57
outside x 5.60 x 4.5717.30 bot.dome inside
outside17.40 Top dome inside
22
2
44
22
22
2222
outside17.50 Shaft inside x 4.00 x 20.00
outside x 4.20 x 20.0017.60 Partition wall inside x 5.70 x 6.30
outside x 5.90 x 6.3017.70 Walkways
2222
Length (m) HYSD Steel (MT)12.57 0.75% 0.80
125.66
6.23 1.50% 0.7046.75
98.17 2.75% 21.60490.84
19.30 1.00% 1.5080.42
96.38 3.00% 23.20321.25
11.66 0.75% 0.7058.31
13.27 0.75% 0.8055.29
103.04 1.20% 9.901030.44
0.30 1.500.63 3.15
57.1938.64
6.18 1.50% 0.7015.46
4.64 2.00% 0.707.73
46.37 1.50% 5.6015.46
282.74 2.00% 45.30
Volume (m3)Formwork
(m2)
77.28 2.75% 17.0025.76
193.59 2.00% 31.0049.32
10.40 1.50% 1.2086.71
1.08 1.50% 0.109.00
0.34 1.50% 0.002.25
1.31 1.50% 0.2025.00
0.29 1.50% 0.003.61
0.08 1.50% 0.000.25
45.92 2.20% 8.10459.18
131.10
23.00
117.86
16.00
148.0059.00
8.009.007.54
237.50253.34143.42160.63
58.3158.31
125.66
125.66502.65527.79225.63233.55126.82
Annular Circular FootingSolid Circular FootingPile Foundation
Karnataka Municipal Reforms Project (KMRP) Detailed Project Report- New OHTat Jewargi Town
Shah Technical Consultants Pvt Ltd (STC) 44of 47
Si. No. Description Unit Qty.
1 Earth work excavation
0 to 2 mtr Depth
a In all soils Cum 59.00b In disintegrated rock, soft rock wihtout resorting to blasting.
2m to 4 mtr Depth Cum
cCum
2
R.M 25.00
3 PCC M7.5B below pilecap Cum 9.00PCC M10B within shaft wall area at ground level
Cum 7.60
4
Cum 282.80Pilecap Cum 77.30
Civil Work Items - RCC Over Head Tank of 2000 cu.m capacity and over 30m staging height
Earthwork in excavation for foundation for pile caps in all types of strata other than hard rock upto 3m depth
Boring in all types of soil (excluding rock) for piling of 600 dia piles including protection of sides by either using temporary liner or driller's mud, etc. complete
Providing M-35 for R.C.C. 600 dia cast in situ bored piles, each of load capacity as designed, place through steel shell sunk to the required depth through all type of strata excluding provision of reinforcement including placing concrete by tremmy arrangment including all leads and lifts,compaction of concrete including chipping and dressing of RCC Piles,cleaning the reinforcement etc complete.
Karnataka Municipal Reforms Project (KMRP) Detailed Project Report- New OHTat Jewargi Town
Shah Technical Consultants Pvt Ltd (STC) 45of 47
Si. No. Description Unit Qty.
5 RCC M 30C grade concrete for RCC Shaft. 102.20
6 RCC M 30C grade for RCC work (excluding cost of reinforcement)
Top, middle and bottom ring beam Cum 38.90Bottom dome Cum 11.66Conical dome Cum 96.38Walkway Slab Cum 13.50Side wall Cum 98.20Top dome Cum 12.60Internal RCC Circular Partition wall Cum 46.00
Karnataka Municipal Reforms Project (KMRP) Detailed Project Report- New OHTat Jewargi Town
Shah Technical Consultants Pvt Ltd (STC) 46of 47
Si. No. Description Unit Qty.
7Cum 3.10
8 HYSD steel reinforcement M Ton 132.00
9
Sqm 564.90
10
2779.30
11
23.00
12
1
1316.00
Cement mortar plastering 1:3 proportion 12 mm thick for both inside and outside surface for top dome
Plastering in C.M. 1:3 proportion including smooth finishing with minimum 2% of approved quality of water proof compound for RCC over head tank and giving satisfactory water proof testing for side walls, shell portion, bottom dome, bottom slabs
Two coats of water proof cement painting of approved colour and shade over one coat of primer before removal of scaffolding for new R.C.C. over head tanks
M.S. ladder 45 cms. wide using angle iron of size 65 mm x 65 mm x 8 mm and 20 mm M.S. bars at 25cms. centre to centre with necessary supports of same angle iron as directed including hand railing on both sides with 25mm dia G.I. pipes with angle iron props at 2 mtrs, interval and 0.5 mtr, height
M.S. Inspection door of size 60 cms x 60 cms. including M.S. frame, size 50 x 50 x 6 mm and shutters of 3mm thickness with hinges at top and locking arrangements, painting
Aluminium monkey ladder 45 cms. wide including hand railing & cage to be provided inside the tank
Karnataka Municipal Reforms Project (KMRP) Detailed Project Report- New OHTat Jewargi Town
Shah Technical Consultants Pvt Ltd (STC) 47of 47
Si. No. Description Unit Qty.
14
Mtr 117.90
15 Pull and push type rolling shutters of approved make as per specifications Sqm 3.15
16Cum 41.00
Supplying & fixing 40 mm dia G.I. medium duty pipes hand railing 3 rows fixed to 1:2:4 (M-150) vibrated R.C.C. post of size 100 x 150 mm at top and 150 x 150 mm at bottom placed at 2 Mtr. intervals for a height of 750 mm painting G.I. pipes with two coats of anticorrosive steel paint over a primer coat
Refilling pipeline trenches and foundation with selected available earth from trench excavation and foundation
