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8/9/2019 Economics of R.C
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Economics of R.C.C. Water tank RestingEconomics of R.C.C. Water tank RestingEconomics of R.C.C. Water tank RestingEconomics of R.C.C. Water tank Restingover Firm Ground vis-a-vis Pre-stressedover Firm Ground vis-a-vis Pre-stressedover Firm Ground vis-a-vis Pre-stressedover Firm Ground vis-a-vis Pre-stressed
Concrete Water Tank Resting over FirmConcrete Water Tank Resting over FirmConcrete Water Tank Resting over FirmConcrete Water Tank Resting over Firm
GroundGroundGroundGround
Posted in Concrete Engineering, Prestress Engineering, Project Reports, Research Papers | Email This Post |
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By
MS. SNEHAL R. METKAR
(P.G. STUDENT)
DEPARTMENT OF CIVIL ENGINEERING
(STRUCTURAL ENGINEERING IIND YEAR)
P.R.M.T OF TECH. & RESEARCH, BADNERA-AMRAVATI
SANT. GADGE BABA (AMARAVATI) UNIVERSITY (MAHARASHTRA)
COUNTRY INDIA – 444701
GUIDED BY
Prof A. R. Mundhada
(PROFESSOR)
DEPARTMENT OF CIVIL ENGINEERING,
P.R M.I.T.R., BADNERA, AMRAVATI.
MAHARASHTRA, INDIA-4444701,
Abstract Abstract Abstract Abstract
Water tanks are used to store water and are designed as crack free structures, to eliminate any leakage. In this paper design of two types
of circular water tank resting on ground is presented. Both reinforced concrete (RC) and prestressed concrete (PSC) alternatives are
considered in the design and are compared considering the total cost of the tank. These water tank are subjected to the same type of
capacity and dimensions. As an objective function with the properties of tank that are tank capacity, width &length etc.
A computer program has been developed for solving numerical examples using the Indian std. Indian Standard Code 456-2000, IS-3370-
I,II,III,IV & IS 1343-1980. The paper gives idea for safe design with minimum cost of the tank and give the designer the relationship curve
between design variable thus design of tank can be more economical ,reliable and simple. The paper helps in understanding the design
philosophy for the safe and economical design of water tank.
KeywordsKeywordsKeywordsKeywords
Rigid based water tank, RCC water tank, Prestressed Concrete, design, details, minimum total cost, tank capacity
I. INTRODUCTIONI. INTRODUCTIONI. INTRODUCTIONI. INTRODUCTION
Storage reservoirs and over head tanks are used to store water, liquid petroleum, petroleum products and similar liquids. The force analysis
of the reservoirs or tanks is about the same irrespective of the chemical nature of the product. In general there are three kinds of water
tanks-tanks resting on ground Underground tanks and elevated tanks. Here we are studying only the tanks resting on ground like clearwater reservoirs, settling tanks, aeration tanks etc. are supported on ground directly. The wall of these tanks are subjected to pressure and
the base is subjected to weight of Water.
In this paper, both types of reinforced concrete and prestesses concrete water tanks resting on ground monolithic with the base Are design
Pile Testing
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and their results compared. These tanks are subjected to Same capacity and dimensions. Also a computer program has been developed for
solving numerical examples using IS Code 456-200IS-1343-1984,IS 3370-Part I,II,III,IV 1965 & IS Code 1343-1980. From the analysis it is
conclude that for tank having larger capacity (greater than 10 lakh liter) prestesses concrete water tank is economical.
ObjectiveObjectiveObjectiveObjective
• To make the study about the analysis and design of water tank.
• To make the guidelines for the design of liquid retaining structure According to IS code.
• To know about design philosophy for safe design of water tank.
• To develop program for water tank to avoid tedious calculations.
• To know economical design of water
• This report is to provide guidance in the design and construction of circular priestesses concrete using tendons
Previous ResearchPrevious ResearchPrevious ResearchPrevious Research
From the review of earlier investigations it is found that considerable work has been done on the method of analysis and design of water
tanks.
Tanetal. [1]:- (1993) presented the minimum cost design of reinforced concrete cylindrical water tanks based on the British Code for water
tanks, using a direct search method and the (SUMT). The cost function included the material costs of concrete and steel only. The tank wall
thickness was idealized with piecewise linear slopes with the maximum thickness at the base.
Thakkar and Sridhar Rao [2] (1974), discussed cost optimization of non cylindrical composite type prestressed concrete pipes based on the
Indian code.
Al-Badri [3] (2005) presented cost optimization of reinforced concrete circular grain silo based on the ACI Code (2002). He proved that the
minimum cost of the silo increases with increasing of the angle of internal friction between stored materials, the coefficient of friction
between stored materials and concrete, and the number of columns supporting hopper . Al-Badri (2006) presented the minimum cost
design of reinforced concrete corbels based on AC I Code (2002). The cost function included the material costs of concrete, formwork and
steel reinforcement. He proved that the minimum total cost of the corbel increases with the increase of the shear span, and decreases with
the increase of the friction factor for monolithic construction.
Hassan Jasim Mohammed [4] studied the economical design of concrete water Tanks by optimization method. He applied the optimization
technique to the structural design of concrete rectangular and circular water tank, considering the total cost of the tank as an objective
function with the properties of the tank viz. tank capacity, width and length of the tank, unit weight of water and tank floor slab thickness
as design variables. From the study he concluded that an increased tank capacity leads to increased minimum total cost of the rectangular
tank but decreased minimum total cost for the circular tank. The tank floor slab thickness constitutes the minimum total cost for two types
of tanks. The minimum cost is more sensitive to changes in tank capacity and floor slab thickness of rectangular tank but in circular type is
more sensitive to change in all variables. Increased tank capacity leads to increase in minimum total cost. Increase in water depth in
circular tank leads to increase in minimum total cost.
Abdul-Aziz & A. Rashed [5] rationalized the design procedure for reinforced and prestressed concrete tanks so that an applicable Canadian
design standard could be developed. The study investigates the concept of partial prestressing in liquid containing structures. The paper
also includes experimental and analytical phases of total of eight full scale specimens, representing segments from typical tank walls,
subjected to load and leakage tests. In analytical study a computer model that can predict the response of tank wall segments is described
and calibrated against the test results. The proposed design procedure addresses the leakage limit state directly. It is applicable for fully
prestressed, fully reinforced and partially prestressed concrete water tanks. The conclusions that are drawn are as follows:-
• A design method based on limiting the steel stress, does not produce consistent crack or compression zone depths under the application
of prestressing nor under a combination of axial load and moment.
• A design method based on providing a residual compressive stress in concrete dose not utilizes non-prestressed reinforcement effectively.
• Relaxing the residual compressive stress requirement permits a more efficient design. The stresses in non-prestresssed steel are higher,
but remain below yield under service load. Therefore, less reinforcement is required.
• Load eccentricity significantly affects the behavior of the prestressed concrete sections. The behavior with a small load eccentricity, less
than about half the thickness, the section may be treated as a flexure member.
• The ratio of non prestressed steel to prestressed steel in partially prestressed concrete section has a significant effect on the member
serviceability and strength. Choosing the ratio such that both non-prestress and prestressed steel reach their strength simultaneously
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utilizes both types of steel at the ultimate limit state effectively.
• Increasing the wall thickness is very effective in increasing the capacity of the section and improving its serviceability by increasing the
compression zone depth and reducing the deformations.
Chetan Kumar Gautam [6] Highlights the point named “Comparison of Circular Reinforced Concrete and Prestressed Concrete Underground
Shelter”. In his paper, design of two types of large circular underground shelters is presented. The shelters are made of precast concrete
sections. Both RC and PSC alternatives are considered in the design and compared. The shelters are subjected to same type of external
loadings and support conditions. The study conclude that the feasibility of using the vertical casting process of making the modules of shelters as it is suitable for manufacturing of large diameter pipes. He also suggested that the incorporation of fibers, specially steel fibers
improves a host of properties of concrete, including its crack resistance, f lexural strength, ductility, etc. Thus, the possibility of incorporating
fibers in concrete shelter may be explored.
II DESIGN PHILOSOPHY II DESIGN PHILOSOPHY II DESIGN PHILOSOPHY II DESIGN PHILOSOPHY
For R.C.C. water tank
For Prestresed Concrete water tank
For R.C.C Structure
Permissible stresses in concrete
• For resistance to cracking:-
Design of liquid retaining structure is different from R.C.C. structures. As it requires that concrete should not crack and hence tensilestresses in concrete should be within permissible limit.(i.e. TYPE-I structure).A reinforced concrete member of liquid retaining structure is
design on the usual principle ignoring tensile resistance of concrete in bending. accordingly it should be ensure that tensile stresses on the
liquid retaining face of the equivalent concrete section dose not exceed the permissible tensile strength of concrete as given in table1.
Grade of
concrete
Permissible stress Shear=
(Q/bjd)
(N/mm^2)
Direct
Tension(?ct)
(N/mm^2)
Tension due
to
Bending(?cbt)
(N/mm^2)
M15 1.1 1.5 1.5
M20 1.2 1.7 1.7
M25 1.3 1.8 1.9
M30 1.5 2.0 2.2
M35 1.6 2.2 2.5
M40 1.7 2.4 2.7
Table 1(Permissible Compressive Stresses In Calculations Relating To Resistance To Cracking)
• For strength calculation
In strength calculations the permissible Concrete stresses shall be in accordance with Table1. Where the calculated shear stress in concrete
a lone exceeds the permissible value, reinforcement acting in conjunction with diagonal compression in the concrete shall be provided to
take the whole of the shear.
Permissible Stresses In Steel
• For resistance to cracking.
When steel and concrete are assumed to act together for checking the tensile stress in concrete for avoidance of crack, the tensile stress in
steel as in table 2will be limited by the requirement that the permissible tensile stress in the concrete is not exceeded so the tensile stress
in steel shall be equal to the product of modular ratio of steel and concrete, and the corresponding allowable tensile stress in concrete.
• For strength calculations
In strength calculations the permissible stress shall be as given in table 2.
TYPE OF STRESS IN
STEEL REINFORCE
MENT
PERMISSIBLE STRESSES
IN N/mm2
Plain round High yield
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mild steel
bars
strength
deformed
bars(HYSD)
1)Tensile stresses in the
members under direct
tension(?s)
115 150
2) Tensile stress in
members in
bending(?st)
On liquid retaining face
of members115 150
On face of away from
liquid for members less
than 225mm
115 150
On face away from
liquid for members
225mm or more in
thickness
125 190
3) Tensile stresses in
shear
reinforcement(?sv)
For members less
than225mm in
thickness
For members 225mm
or more in thickness
115 150
125 175
Table 2 (Permissible Stresses In Steel Reinforcement For Strength Calculation)
Design Requirement
Generally M30 grade of concrete should be used Design Mix (1:1*1/2:3)Steel reinforcement should not less than0.3% of the gross section
shall be provided in each direction Floors:-floor may be constructed of concrete with nominal % of reinforcement smaller than provided in
table 1.they are cast in panels with sides not more than 45m and with contraction or expansion joints in between..In such cases a screed or
concrete layer(M10) not less than 75mm thick shall placed first on the ground and covered with a sliding layer of bitumen paper to destroy
the bond between the screed and the floor.
Minimum Cover:- 35mm(both the faces).
Minimum Reinforcement:-Overall .24% of total cross section should be provided.
Walls:-1) provision of joints
( a ) Where it is desired to allow the walls to expand or contract separately from the floor , or to prevent moments at the base of the wall
owing to fixity to the floor sliding joints may be employed.
( b) The spacing of vertical movement joints should be as discussed. while the majority of these joints may be of the partial or complete
contraction type , sufficient joints of the expansion type should be provided to satisfy the requirements given in article.
2)Pressure on wall
(a) In liquid retaining structures with fixed or floating covers the gas pressure developed above liquid surface shall be added to the liquid
pressure .
(b)When the wall of liquid retaining structure is built in ground, or has earth embanked against it ,the effect of earth pressure shall be
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taken in to account .
III Design stepes:
• Calculate diameter and height of water tank
• Assumed suitable thickness
• Calculate designed constants
• Calculate hoop tension, maximum bending moment by using IS 1370 part IV.
• Calculate hoop steel(provide in the form of rings per meter height)
• Check the assume thickness with given permissible values of tensile stresses of concrete in direct tension for the given grade of concrete.
• Check of thickness for bending
• Provide vertical steel
• Design base slab
• Draw details
detail
IV PRESTRESSING DEFINITION
Introduction of compressive stresses to a structural member with high-strength steel that counteract the tensile stresses resulting from
applied loads
Prestressed Concrete
Pre-Tensioned (cast off-site in beds- precast members)
Post-Tensioned (cast on-site in place)
All types of structure can be built with reinforced and pre-stressed concrete: columns, piers, walls, slabs, beams, arches, frames, even
suspended structures and of course shells and folded plates.
• Tanks
• Foundation panels
• Poles
• Modular block retaining wall system
• Wall panels
• Concrete units
• Slabs
• Roofing and flooring
• Lintel and sunshade
• Beams
• Columns girders
Tanks:-
In the construction of concrete structures for the storage of liquids, the imperviousness of concrete is an important basic requirement.
Hence, the design of such construction is based on avoidance of cracking in the concrete. The structures are prestressed to avoid tension in
the concrete. In addition, prestressed concrete tanks require low maintenance. The resistance to seismic forces is also satisfactory.
Prestressed concrete tanks are used in water treatment and distribution systems, waste water collection and treatment system and storm
water management. Other applications are liquefied natural gas (LNG) containment structures, large industrial process tanks and bulk
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storage tanks. Strand Wrapped circular pre-stressed concrete tanks are long life liquid storage structure with virtually no maintenance.
Concrete construction makes for a substantial, sturdy tank structure that easily contain the internal liquid pressure while comfortably
resisting external forces such as earthquake, wind.
Pre-stressed concrete is the most efficient material for water tanks and coupled with the circular shape, eliminates all stress conditions. By
placing the steel of the pre-stressed strands in tension and the concrete in compression, both materials are in an ideal states and the loads
are uniformly distributed around the tank circumference.
Properties 1) Low maintenance can be enjoyed throughout the life as these are built with concrete, durable material that never corrodes and does not
require coatings when in contact with water or the environment.
2) Pre-stressing counteracts the differential temperature and dryness loads that a tank core wall experience. The tank walls are wet on the
inside and dry on outside and the temperature varies between the two sides. If not properly accounted for, these moisture and temperature
differential will cause a tank wall to bend and crack. Counteract these force in both the vertical and horizontal direction and diminish
subsequently the cracking and leaking
3) Tanks are very ductile, enabling to withstand seismic forces and varying water backfill.
4) Tanks utilize material efficiently – steel in tension, concrete in compression
5) Pre-cast tanks can store or treat anything from potable water to hazardous waste to solid storage bins.
6)Storage capacities can range from 0.4 to 120 mega liters
7) Diameters of the tank can vary up to 90 m
V Design philosophy
A. Loads: Circumferential prestressing also typically causes vertical bending moment from other loading condition.
B. Freeboard: freeboard should be provided in the tank wals to minimize earthquake- induced hydrodynamic effects on a flat roof.
C. Wall: The design of the wall should be based on elastic cylindrical shell analysis, considering the effects of prestressing, internal loads
and other external loads.cast in place concrete walls is usually priestesses circumferentially with high-strength strand tendons placed in
ducts in the wall .the wall may be priestesses with bonded and unbounded tendons. Vertical prestessed reinforcement near the center of
the wall thickness, or vertical non prestessed reinforcement near each face, may be used. Non priestesses reinforcement may be provided
vertically in conjunction with vertical prestressing.
Precast concrete walls usually consist of precast panels curved to the tank radius with joints between panels filled with high-strength
concrete. the panels are post-tensioned circumferentially by high strength strand tendons. the tendons maybe embedded within the precast
panels or placed on the external surface of the wall and protected by shortcreat .the wall panels may be prestessesd vertically with
pretensioned strands or post-tensioned tendons.non prestesses reinforcement may be provided vertically with or without vertical
prestressing.
Construction Methodology The construction of the tanks is in the following sequence. First, the concrete core is cast and cured. The surface is prepared by sand or
hydro blasting. Next, the circumferential prestressing is applied by strand wrapping machine. Shotcrete is applied to provide a coat of
concrete over the prestressing strands. A few photographs are provided for il lustration.
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IS: 3370 (Code of Practice for Concrete Structures for the Storage of Liquids) provides guidelines for the analysis and design of liquid
storage tanks. The four sections of the code are titled as follows.
Part 1: General Requirement
Part 2: Reinforced Concrete Structures
Part 3: Prestressed Concrete Structures
Part 4: Design Tables
The following types of boundary conditions are considered in the analysis of the cylindrical wall.
a) For base: fixed or hinged
b) For top: free or hinged or framed.
1)For base
Fixed: When the wall is built continuous with its footing, then the base can be considered to be fixed as the first approximation.
Hinged: If the sub grade is susceptible to settlement, then a hinged base is a conservative assumption. Since the actual rotational restraint
from the footing is somewhere in between fixed and hinged, a hinged base can be assumed. The base can be made sliding with
appropriate polyvinyl chloride (PVC) water-stops for liquid tightness.
2) For top
Free: The top of the wall is considered free when there is no restraint in expansion.
Hinged: When the top is connected to the roof slab by dowels for shear transfer, the boundary condition is considered to be hinged.
The hydrostatic pressure on the wall increases linearly from the top to the bottom of the liquid of maximum possible depth. If the vapour
pressure in the free board is negligible, then the pressure at the top is zero. Else, it is added to the pressure of the liquid throughout the
depth. The forces generated in the tank due to circumferential prestress are opposite in nature to that due to hydrostatic pressure. If the
tank is built underground, then the earth pressure needs to be considered.
The hoop tension in the wall, generated due to a triangular hydrostatic pressure is given as T = C Tw H Ri
The bending moment in the vertical direction is given as
M = CMwH3
The shear at the base is given by the expression V = C Vw H
Where,
CT = coefficient for hoop tension
CM = coefficient for bending moment
C V = coefficient for shear
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w = unit weight of liquid
H = height of the liquid
Ri = inner radius of the wall.
The values of the coefficients are tabulated in IS:3370 – 1967, Part 4, for various values of H2/Dt, at different depths of the liquid. D and t
represent the inner diameter and the thickness of the wall, respectively. The typical variations of CT and CM with depth, for two sets of
boundary conditions are illustrated. The roof can be made of a dome supported at the edges on the cylindrical wall. Else, the roof can be a
flat slab supported on columns along with the edges. IS:3370 – 1967, Part 4, provides coefficients for the analysis of the floor and roof
slabs.
Design steps
• Calculate diameter and height of water tank
• Assumed suitable thickness
• Calculate designed constants
• Calculate hoop tension, maximum bending moment by using IS 1370 part IV.
• Check the assume thickness with given permissible values of tensile stresses of concrete in direct tension for the given grade of concrete.
• Actual circumferential prestress i.e. actual direct compressive stress (fc)
• Provide circumferential steel , Provide vertical steel
• Check for ultimate collapse and cracking
• Non prestressing steel /untensioned steel
• Design base slab
• Draw detail
Comparison of R.C.C. water tank and Prestrssed water tank Comparison of R.C.C. water tank and Prestrssed water tank Comparison of R.C.C. water tank and Prestrssed water tank Comparison of R.C.C. water tank and Prestrssed water tank
The tanks to be consider having some common data such as the tanks are having same capacity, same diameter, same height, same grade
of concrete i. e. (M40) & (M50), the thickness of tank floor should be taken either 150mm or equal to the wall thickness(if greater than
150mm) for RCC water tank and minimum thickness for priestesses concrete water tank is 120mm.We consider tank capacity for both the
cases (i.e. RCC & Priestesses) reimaging from 1000 m3 to 9000 m3. for both the grade of concrete i.e. (M40 & M50). The result so
obtained as given in following table3
Schedule For RCC Water Tanks & Prestressed
Concrete Water Tanks Estimate Details
CAPACITYGRADE OF
CONCRETE
COST
OF P.C.
% OF
COST
COST OF
R.C.
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WATER
TANK
C.WATER
TANK
m3 Rs Rs
1000 M40 2056116 11.47 1844521
M50 2101677 9.43 1920546
2000 M40 2777828 -20.33 3486806
M50 2845004-21.69 3633328
3000 M40 3811166 -24.87 5072773
M50 3897242-26.22 5282492
4000 M40 5268049 -21.06 6673611
M50 5404513-22.50 6973950
5000 M40 6696401 -18.14 8180441
M50 6852226-20.01 8567341
6000 M40 7901981 -22.35 10177486
M50 8143194-23.45 10637885
7000 M40 8988532 -19.34 11144740
M50 9255833-21.42 11778868
8000 M401169380
-15.02 13761735
M50 1199296-16.63 14385223
9000 M40 1277439 -16.45 15290975
M50 1309013-18.05 15975177
NOTE: (Negative value of % saving indicates that prestressed concrete tank is economical than RCC water tank and vice-à-versa)
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Figure 1: Variation Of Cost With Capacity Of Water Tank & Grade Of Concrete
Figure 2 Variation Of Cost For Both Type Of Water Tank With Same Grade Of Concrete(M40)
Figure 3 Variation Of Cost For Both Type Of Water Tank With Same Grade Of Concrete(M50)
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Figure 4 Variation of % of saving for given capacity with given grade of concrete(M40)
Figure 5 Variation of % of saving for given capacity with given grade of concrete(M50)
The aim of this paper is to compare the cost of R.C.C. water tanks resting over firm ground with the cost of Prestressed concrete water
tanks. In India at least, most of the small & medium sized water tanks are constructed in RCC. Senior engineers and those in the know
maintain that prestressed concrete water tanks are not worth trying for smaller capacities. Besides cost, other reason may be that
prestressed concrete construction involves skilled labor & supervision. Furthermore, prestressing is a closely guarded technology in this
country & information is not available that easily.
There is no clear-cut definition of “Medium Size”. The thumb rule passed on in the field from one generation of engineers to the next, fixes
a value around 10 lac liters. Therefore, this study encompasses tanks from 10 lac liter capacity to 90 lac liter capacity. A couple of cases of
both varieties were designed manually. Design & Estimation programs were developed in MS EXCEL for both RCC & Prestressed concrete.
The programs were finalized after a number of trial runs & corrections.
Results obtained are compiled in figures numbered 1 to 5 & Table numbered 3. D/H ratio for all the tanks is maintained at 4 based on the
recommendations of the Preload Engineering Company of the US, a world leader in the field of prestressed concrete water tanks. It should
be noted that an increase in tank wall thickness results in decreased flexural steel in case of RCC. However, in case of prestressed concrete,
an increased thickness leads to a greater prestressing force & consequently more prestressing steel. Thus, increased thickness leads to
increased cost in case of prestressed concrete.
Table3 presents the total cost of each tank along with the % difference. “+” means costlier prestressing & “-“ means cheaper prestressing.
As the tank capacity increases, the cost of tank increases. But the concept of “economics of scale” holds good i.e. the cost of a tank of 20
lac liter capacity is less than double the cost of a tank of 10 lac liter capacity. Similarly, the cost of a tank of 90 lac liter capacity is less than
9 times the cost of a tank of 10 lac liter capacity. It can be clearly established that the grade of concrete hardly makes any difference in the
costing. Because of its nature, the water tank design is never an impending or boundary line design. The factor of safety is high & the
actual stresses are much lower than the permissible ones. An increased permissible stress for a higher grade of concrete hardly makes any
difference to the final outcome.
Finally, a study of the same Table3 confirms that the RCC tank is cheaper only for 10 lac liter capacity. For higher capacities, prestress
concrete tank is always cheaper by @ (20 +/- 5) %. This is because the thickness of an RCC tank increases many-folds for higher
capacities. Thickness in fact seems to be an important criterion even for prestressed tanks. An increased thickness leads to an increased
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prestressing force. More steel is required to generate this higher prestressing force resulting in higher cost.
CONCLUSIONCONCLUSIONCONCLUSIONCONCLUSION
RCC tanks are cheaper only for smaller capacities up to 10-12 lac liters. For bigger tanks, Prestressing is the superior choice resulting in a
saving of @ 20%.
REFERENCES:REFERENCES:REFERENCES:REFERENCES:
1 Tanetal (1966) “Minimum Cost Design Of Reinforced Concrete Cylindrical Water Tanks Based On The British Code For Water Tanks, Using
A Direct Search Method And The (SUMT). European Journal Of Scientific Research ISSN 1450 -216XVol.49No.4(2011),pp.510-520.2 Thakkar and Sridhar Rao (1974)”Cost Optimization Of Cylindrical Composite Type Prestesses Concrete Pipes Based On The Indian Code”
Journal of Structural Engineering 131: 6.
3 Al-Badri (2005) “Cost Optimization Of Reinforced Concrete Circular Grain Silo Based On ACI Code (2002)American Concrete Institute
Structural Journal, May- June 2006.
4 Hassan Jasim Mohammed “ Economical Design Of Water Tanks” European Journal Of Scientific Research ISSN 1450
-216XVol.49No.4(2011),pp.510-520.
5 Abdul-Aziz & A. Rashed “Rational Design Of Priestesses And Reinforced Concrete Tanks” Dept Of Civil & Environmental Engineering.
University Of Alberta, Edmontan, Alberta Canada T6g-267.Eurojournals Publishing. Inc.2011
6 Chetan Kumar Gautam “Comparison Of Circular RC And PSC Underground Shelters” The Indian Concrete Journal April 2006.
7 Precon “Designing Of Circular Prestressed Concrete Tanks To The Industry Standards Of The AWWA And ACI” journal of priestesses
concrete institute vol.12,apr. 1967
8 IS: 456-2000. Indian Standard Code of Practice For Reinforced Concrete.
9 IS 3370-Part I,II,III,IV 1965 & IS Code 1343-1980 Indian Standard Code of Practice For Liquid Retaining Structures.
10 IS: 1343- 1980. Indian Standard Code of Practice For Prestressed Concrete (First Revision).
11 Lin, T.Y, and NED H BURNS “Prestressed Concrete”, Third Edition , John Wiley & Sons[ ASIA] Pt e Ltd. , Singapore 129809.
12 N. Krishna Raju, 2007. “Prestressed Concrete”, Fourth Edition, Tata McGraw- Hill Company Ltd., New Delhi.
13 A.K Jain Reinforced concrete (vol-1,vol-2)
14 B.N Dutta, 2009 “Estimating and Costing In Civil Engineering”, Twenty- Sixth Revised Edition UBS Publishers’ Distributors Pvt. Ltd. New
Delhi.
15 Current Schedule of Rates (CSR), 2010-2011, for Public Works Region, Amravati.
16 Schedule Of Rates Year 2010-2011, For Maharashtra Jeevan Pradhikaran, Nagpur Region17 Bundy , B. D. , 1984. ” Basic Optimization Methods “, Edward Arnold Publishers.
18 Fintel, M., ,1974. ” Handbook of Concrete Engineering”, USA.
19 Gray ,W.S. and Manning ,G.P., 1960. ” Concrete Water Tower, Bunkers, Silos and Other Elevated Structures” , 3rd ed. , London.
20 Manning, G.P., 1973. ” Reinforced Concrete Reservoirs and Tanks,1st ed. London.
We at engineeringcivil.com are thankful to MS. SNEHAL R. METKAR for submitting this useful information to us. We hope this will be of
great help to all those who are looking forward for Economics of R.C.C. Water tank Resting over Firm Ground vis-a-vis Pre-stressed
Concrete Water Tank Resting over Firm Ground.
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pipelines?
Analysis and design of prestressed concrete box girder bridge
Should mild steel or high yield steel be adopted as reinforcement of water-retaining
structures?
What are the IS Codes used for Structural Engineering And Structural Sections?
Comments
HARSHAL.S.KHODE( INSPECTION ENGINEER,CIVIL/STRUCTURAL) OIL AND GAS DIVISION June 16, 2011 at 2:42 pm
Eurocode DesignSoftwareRFEM - Dlubal Software for
Eurocode Free 30-day Fully
Functional Trial!
nomics of R.C.C. Water tank Resting over Firm Ground vis-a-... http://www.engineeringcivil.com/economics-of-r-c-c-water-tank-...
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This is very much useful for EVERY CIVIL ENGINEERING PROFESSIONAL.BECAUSE I AM WORKING IN CONSULTANT FOR OIL ANS
GAS DIVISION.I AM CARRIED OUT VERY BIG UNDER GROUND TANK FOR STORAGE OF WATER FOR COOLING TOWER IN
PETROCHEMICALS REFINERIES.SO THIS IS MUCH HELP TO ME. ME ALSO THANKS FULL TO MISS SNEHAL.R.METKAR WHO PUBLISH
THIS ARTICLE EXCELLENT.
Reply Link Quote
Darshan July 5, 2013 at 12:36 am
Sir, I am student in M.tech and me also want to know design and detailing of prestressed concrete tanks.
Reply Link Quote
Abhinandan R.Gupta June 21, 2011 at 1:48 am
This study will prove very usefull for civil engineers. I would like to thanks the author Miss. Metkar for sharing such usefull data with
us.
Reply Link Quote
Poovalagan J September 12, 2011 at 1:21 am
Really its very useful for all the Civil Engineers. Thank you for sharing valuable information useful for civil Projects….
Reply Link Quote
Nitin Dixit September 16, 2011 at 3:56 am
Very Much Appreciated work . Thank You for providing such a useful data to us.
Reply Link Quote
SR Albina November 23, 2011 at 1:53 pm
appreciated very much. we 150 bed mission hospital wants to make a R C C overhead tank what capacity we need? can you help me
with a design, cost, and a consulting Engineer at NIIT Kozhikode. albina
Reply Link Quote
Rohan Kakde November 25, 2011 at 1:48 am
Very gud article.
Reply Link Quote
Pravin Shinde December 23, 2011 at 3:42 am
Hi, how do we workout the labour cost for the RCC overhead water tank for govt work everything including material will be supplied
by the contractor! we have to only have to supplu the labour, carpenter & fitter. if any body can guide me i will be thank full.
Reply Link Quote
ALPESH PATEL January 4, 2012 at 2:36 am
Really i appreciate for this type of artical
Also We are planning to design rectangular tank of aprox 45 x 55 x 7 M. ht. Size of tank rest on ground having rock bed
can u guide me for design steps and regarding construction joint .If any body helpful i will be thankful.
Reply Link Quote
Piyush Diwan January 9, 2012 at 4:37 am
Dear Mr.Alpesh patel,
For bigger water storage we have idea of putting GRP/SMC panel tank to avoid complication of RCC job and the total time
needed for the same. Our principal is the no.1 co. in India supplying GRP/SMC panel tank for raw/treated water tanks in
industries and communities. Pls give your mail IDs for sending the other details. You will certainly appreciate this.
Reply Link Quote
Santosh February 9, 2012 at 12:26 am
nomics of R.C.C. Water tank Resting over Firm Ground vis-a-... http://www.engineeringcivil.com/economics-of-r-c-c-water-tank-...
of 18 2/4/2015 9:08 AM
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Really its very useful . Please provide me Calculation steps and total cost of 12 M X 8 M x 5 M RCC Tank as water storage tank above
ground.
Reply Link Quote
Ashok kumar sarma July 15, 2012 at 4:06 am
please provide me detail calculation of cost of 10M*10M*5m RCC water reservoir
Reply Link Quote
S.K.Sen March 5, 2012 at 12:04 am
More usefull for PHE Engineer’s
Reply Link Quote
S.K.Sen Raipur March 5, 2012 at 11:16 pm
its very useful . Please provide me Calculation steps and total cost of 4.5M,ht. dia X 6M & 1.5m below G.L. R.C.C. circular Tank as
Open at top,water storage tank above ground.
Reply Link Quote
Adnan Galib March 7, 2012 at 12:04 pm
This document really effective to enrich the skill and knowledge on water tank as well.I faced a problem in the construction of a
rectangular water reservoir.I observed some cracks in internal and external walls before imposing the water in it.The crack width is
0.05 mm.The area where the tank is constructed is hilly.Only plate bearing test was carried out to examine the soil bearing
capacity.So,are those cracks will be fatal?what will be the possible cause of those cracks development?
Reply Link Quote
Haneef March 8, 2012 at 10:51 am
I am constructing a water tank in mumbai suburbs so very useful article.
Reply Link Quote
Srinivas. C March 15, 2012 at 8:00 am
Please provide me calculations for an underground rectangular Water tank of internal sizes are 8mx6mx5m (5m deep and dividing
with an internal wall(4mx6m+4mx6m). Tank will be covering with top slab of 150 mm thick.
Thanking you
your’ s Faithfulley
Reply Link Quote
Mehul April 27, 2012 at 3:48 pm
Hey good article. I have doubt regarding the fixity of foundation in P.C. Tanks.
Reply Link Quotearshan May 7, 2012 at 10:46 am
thnk u so much
Reply Link Quote
pankaj anand September 7, 2012 at 12:02 pm
Please provide me calculations for an underground rectangular Water tank of internal sizes are 5mx5mx8m (8m deep ). Tank will be
covering with top slab of 100 mm thick.
Thanking you
your’ s Faithfulley
Reply Link Quote
Fida Hussain November 1, 2012 at 11:42 pm
Really found good knowledge & no doubt it would be usefull for all structural design engineers.
nomics of R.C.C. Water tank Resting over Firm Ground vis-a-... http://www.engineeringcivil.com/economics-of-r-c-c-water-tank-...
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Reply Link Quote
dinesh dadhich March 24, 2013 at 1:37 am
thanks for help . very useful hints for calculation of water tanks.
Reply Link Quote
DEEPAN RAI May 10, 2013 at 10:19 am
thank you so much for all these information cause till now we were doing it very impractically, though it worked but was not
economical.
Reply Link Quote
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