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7/29/2019 Engineeringcivil.com-Economics of RCC Water Tank Resting Over Firm Ground Visavis Prestressed Concrete Water
1/15
engineeringcivil.com
http://www.engineeringcivil.com/economics-of-r-c-c-water-tank-resting-over-firm-ground-vis-a-vis-prestessed-concrete-
water-tank-resting-over-firm-ground.html
Economics of R.C.C. Water tank Resting over Firm Ground vis-
a-vis Pre-stressed Concrete Water Tank Resting over Firm
Ground
Posted in Concrete Engineering, Prestress Engineering, Project Reports, Research Papers | Email This Pos t |
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
Water tanks are used to store water and are designed as crack f ree st ructures, to eliminate any leakage. In
this paper design of two types o f circular water tank resting on ground is presented. Both reinf orced
concrete (RC) and prest ressed concrete (PSC) alternatives are considered in the design and are compared
considering the to tal cost of the tank. These water tank are subjected to the same type of capacity and
dimensions . As an objective f unction with the properties o f tank that are tank capacity, width &length etc.
A computer program has been developedf or 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 f or saf e design with
minimum cos t o f the t ank 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 fo r the saf e and economical design of water tank.
Keywords
Rigid based water tank, RCC water t ank, Prest ressed Concrete, des ign, details, minimum to tal cos t, tank
capacity
I. INTRODUCTION
Storage reservoirs and over head tanks are used to s to re water, liquid petro leum, petro leum products and
similar liquids. The force analysis of the reservo irs or tanks is about the same irrespective of the chemical
nature of the product. In general there are three kinds o f water tanks- tanks rest ing on ground Underground
tanks and elevated tanks. Here we are studying only the tanks res ting on ground like clear water reservoirs,
set tling tanks, aeration tanks etc. are support ed on ground directly. The wall of these tanks are subjectedto pressure and the base is subjected to weight o f Water.
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In this paper, both types o f reinforced concrete and prestesses concrete water tanks resting on ground
mono lithic with the base Are design and their results compared. These tanks are subjected to Same
capacity and dimensions. Also a computer program has been developed f or so lving 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 f or t ank having larger capacity (greater than 10 lakh liter) prestesses concrete water tank is
economical.
Objective
To make the study about the analysis and design of water tank. To make the guidelines f or t he design of liquid retaining st ructure According to IS code.
To know about design philosophy for safe design of water tank.
To develop program fo r water tank to avoid tedious calculations.
To know econo mical design of water
This report is to provide guidance in the design and construction o f circular priestesses concrete using
tendons
Previous Research
From the review of earlier investigat ions it is f ound that cons iderable work has been done on the method
of analysis and design of water tanks.
Tanetal. [1]:- (1993) presented the minimum cos t design of reinforced concrete cylindrical water tanks
based on the British Code f or water tanks, using a direct search metho d and the (SUMT). The cost
f unction included the material costs o f concrete and steel only. The tank wall thickness was idealized with
piecewise linear slopes with t he maximum thickness at the base.
Thakkar and Sridhar Rao [2] (1974), discussed cost opt imization of non cylindrical compos ite type
prestressed concrete pipes based on the Indian code.
Al-Badri [3] (2005) presented cost optimizat ion o f reinf orced co ncrete circular grain silo based on the ACI
Code (2002). He proved that the minimum cost o f the silo increases with increasing of the angle of internal
f riction between sto red materials, the coef f icient o f f riction between sto red materials and concrete, and
the number of columns support ing hopper . Al-Badri (2006) presented the minimum cost des ign of
reinforced concrete corbels based on AC I Code (2002). The cost f unction included the material cos ts of
concrete, f ormwork and steel reinforcement. He proved that the minimum to tal cost o f the corbel increases
with the increase of the shear span, and decreases with the increase o f the f riction f actor f or monolithic
construction.
Hassan Jasim Mohammed [4] studied the economical design of concrete water Tanks by optimizat ion
method. He applied the opt imization technique to the s tructural design of concrete rectangular and circular
water tank, considering the to tal cost o f the tank as an objective f unction with the properties o f the tank
viz. tank capacity, width and length o f the tank, unit weight o f water and tank f loo r slab thickness as designvariables. From the study he concluded that an increased tank capacity leads to increased minimum total
cost of the rectangular tank but decreased minimum to tal cost f or t he circular tank. The tank floor s lab
thickness constitutes the minimum to tal cost f or two t ypes o f tanks. The minimum cost is more sensitive to
changes in tank capacity and f loo r slab thickness of rectangular tank but in circular type is more sens itive
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 .
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Abdul-Aziz & A. Rashed [5] rat ionalized the design procedure f or reinf orced and prestressed concrete
tanks so that an applicable Canadian design standard could be developed. The study investigates the
concept o f partial prestressing in liquid containing structures. The paper also includes experimental and
analytical phases o f to tal of eight full scale specimens, representing segments f rom typical tank walls,
subjected to load and leakage tests . In analytical study a computer model that can predict the respo nse o f
tank wall segments is described and calibrated against the test results . The proposed design procedure
addresses the leakage limit st ate directly. It is applicable f or f ully prestressed, f ully reinfo rced and partially
prestressed concrete water tanks. The conclusions that are drawn are as f ollows:-
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 o f axial load and moment.
A design method based on providing a residual compressive stress in concrete dose not ut ilizes non-
prestressed reinforcement ef f ectively.
Relaxing the residual compressive st ress requirement permits a more ef f icient design. The stresses in
non- prest resssed steel are higher, but remain below yield under service load. Theref ore, less reinf orcement
is required.
Load eccentricity s ignif icantly aff ects t he behavior of the prestressed concrete sections. The behaviorwith a small load eccentricity, less than about half the thickness, the section may be treated as a f lexure
member.
The ratio o f non prestressed steel to prest ressed steel in partially prestressed concrete section has a
signif icant ef f ect on the member serviceability and strength. Choosing the ratio such that both non-
prestress and prestressed steel reach their st rength simultaneously utilizes both types of steel at the
ultimate limit st ate ef f ectively.
Increasing the wall thickness is very ef f ective 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 po int named Compariso n of Circular Reinf orced Concrete and
Prestressed Concrete Underground Shelter. In his paper, design of two types o f large circular underground
shelters is presented. The shelters are made of precast concrete sections. Both RC and PSC alternat ives
are considered in the design and compared. The shelters are subjected to same type of external loadings
and support conditions. The s tudy conclude that the f easibility of using the vertical casting process o f
making the modules of shelters as it is suitable for manufacturing of large diameter pipes. He also
suggested that the incorporation of f ibers, specially steel f ibers improves a host o f properties of concrete,
including its crack resistance, f lexural strength, ductility, etc. Thus, the poss ibility of incorporat ing f ibers in
concrete shelter may be explored.
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 dif f erent f rom R.C.C. st ructures. As it requires that concrete should
not crack and hence tensile st resses in concrete sho uld be within permissible limit.(i.e. TYPE-I structure).A
reinforced concrete member of liquid retaining st ructure is design on the usual principle ignoring tensile
resistance of concrete in bending. accordingly it should be ensure that tensile stresses o n the liquid
retaining face of the equivalent concrete section dose not exceed the permissible tensile strength o f
concrete as given in table1.
Grade ofconcrete
Permissible stress Shear=(Q/bjd)(N/mm^2)
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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 st rength calculations the permissible Concrete s tresses shall be in accordance with Table1. Where the
calculated shear s tress in concrete a lone exceeds the permissible value, reinfo rcement 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 to gether for checking the tensile st ress in concrete f or
avoidance of crack, the tens ile st ress 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 o f steel and concrete, and the corresponding allowable tensile stress in concrete.
For strength calculations
In st rength calculations the permiss ible st ress shall be as given in table 2.
TYPE OF STRESS IN STEEL REINFORCE MENT PERMISSIBLE STRESSES IN N/mm2
Plain ro und mildsteel bars
High yield strength deformedbars(HYSD)
1)Tensile stresses in the members under directtension(?s)
115 150
2) Tensile st ress in members in bending(?st)
On liquid retaining f ace of members 115 150
On face of away f rom liquid f or members lessthan 225mm
115 150
On face away f rom liquid f or members 225mm ormore in thickness
125 190
3) Tensile st resses in shear reinforcement(?sv)
For members less than225mm in thicknessFor members 225mm or more in thickness
115 150
125 175
Table 2 (Permissible Stresses In Steel Reinfo rcement For Strength Calculation)
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Design Requirement
Generally M30 grade o f concrete should be used Design Mix (1:1*1/2:3)Steel reinf orcement sho uld not less
than0.3% of the gross section shall be provided in each direction Floo rs:-f loor may be constructed o f
concrete with nominal % of reinforcement smaller than provided in table 1.they are cast in panels with s ides
not more than 45m and with contract ion o r expansion joints in between..In such cases a screed or concrete
layer(M10) not less than 75mm thick shall placed f irst on the gro und and covered with a sliding layer of
bitumen paper to destroy the bond between the screed and the f loor.
Minimum Cover:- 35mm(both the faces).Minimum Reinf orcement:-Overall .24% of to tal cross section should be provided.
Walls:-1) provision of joints
( a ) Where it is desired to allow the walls to expand or contract separately f rom the f loor , o r to prevent
moments at the base of the wall owing to f ixity to the f loor 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 , suf f icient joints of the expansion type should be provided
to sat isf y the requirements given in article.
2)Pressure on wall(a) In liquid retaining structures with f ixed or f loat ing covers t he gas pressure developed above liquid
surf ace 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 ef f ect
of earth pressure shall be taken in to account .
III Design stepes:
Calculate diameter and height o f water tank
Assumed suitable thickness
Calculate designed constants
Calculate hoop tensio n, maximum bending moment by using IS 1370 part IV.
Calculate hoo p steel(provide in the form of rings per meter height)
Check the assume thickness with given permissible values o f tensile st resses o f concrete in direct
tension f or the given grade of concrete.
Check of thickness f or bending
Provide vertical steel
Design base slab
Draw details
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detail
IV PRESTRESSING DEFINITION
Introduction o f compressive st resses to a st ructural member with high-s trength steel that counteract the
tensile stresses resulting f rom applied loads
Prestressed Concrete
Pre-Tensioned (cast o f f -s ite in beds- precast members)
Pos t-Tensioned (cast on-site in place)
All types of st ructure can be built with reinf orced and pre-stressed concrete: columns, piers , walls, slabs,beams, arches, f rames, even suspended st ructures and o f course shells and f olded plates.
Tanks
Foundat ion 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 st ructures f or the sto rage of liquids, the imperviousness o f concrete is an
important basic requirement. Hence, the design of such const ruction is based on avoidance of cracking in
the concrete. The s tructures are prestressed to avoid tension in the concrete. In addition, prestressed
concrete tanks require low maintenance. The resistance to seismic f orces is also sat isf actory. Prestressed
concrete tanks are used in water treatment and distribution systems, waste water collection and treatment
system and sto rm water management. Other applications are liquef ied natural gas (LNG) containment
st ructures, large industrial process tanks and bulk sto rage tanks. Strand Wrapped circular pre-s tressedconcrete tanks are long lif e liquid sto rage structure with virtually no maintenance. Concrete cons truction
makes f or a substantial, sturdy tank structure that easily contain the internal liquid pressure while
comfort ably resist ing external f orces such as earthquake, wind.
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Pre-st ressed concrete is the most ef f icient material fo r water tanks and coupled with the circular shape,
eliminates all stress conditions. By placing the steel o f the pre-s tressed st rands in tension and the
concrete in compression, both materials are in an ideal states and the loads are unifo rmly distributed
around the tank circumf erence.
Properties
1) Low maintenance can be enjoyed througho ut the lif e 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-s tress ing counteracts the dif f erential temperature and dryness loads that a t ank core wall
experience. The tank walls are wet on the inside and dry on outs ide and the temperature varies between the
two sides. If not properly accounted f or, these moisture and temperature dif f erential will cause a tank wall
to bend and crack. Counteract these f orce in both the vertical and horizo ntal direction and diminish
subsequently the cracking and leaking
3) Tanks are very ductile, enabling to withs tand seismic forces and varying water backf ill.
4) Tanks utilize material ef f iciently st eel in tension, concrete in compress ion
5) Pre-cast tanks can store or treat anything f rom potable water to hazardous waste to so lid sto rage bins.
6)Storage capacities can range f rom 0.4 to 120 mega liters
7) Diameters of the tank can vary up to 90 m
V Design philoso phy
A. Loads: Circumferential pres tressing also typically causes vert ical bending moment f rom other lo ading
condition.
B. Freeboard: f reeboard should be pro vided in the tank wals to minimize earthquake- induced hydrodynamic
eff ects on a f lat roof .
C. Wall: The design of the wall should be based on elastic cylindrical shell analysis, considering the ef f ects
of prestress ing, internal loads and other external loads.cast in place concrete walls is usually priestessescircumf erentially with high-st rength strand tendons placed in ducts in the wall .the wall may be priestesses
with bonded and unbounded tendons. Vertical prestessed reinfo rcement near the center o f the wall
thickness, or vert ical non prestessed reinforcement near each f ace, may be used. Non priestesses
reinforcement may be provided vertically in conjunction with vert ical prest ressing.
Precast concrete walls usually consist o f precast panels curved to the tank radius with joints between
panels f illed with high-st rength concrete. the panels are post -tens ioned circumferentially by high strength
st rand tendons . the tendons maybe embedded within the precast panels or placed on the external surface
of the wall and protected by short creat .the wall panels may be prestessesd vertically with pretensioned
st rands or post -t ensioned tendons.non prestesses reinf orcement may be provided vertically with or
without vertical prestressing.
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Construction Methodology
The construction o f the tanks is in the f ollowing sequence. First, the concrete core is cast and cured. The
surf ace is prepared by sand o r hydro blast ing. Next, the circumf erential prestressing is applied by strand
wrapping machine. Shotcrete is applied to provide a coat o f concrete over the prestressing strands. A f ew
photo graphs are provided for illustration.
IS: 3370 (Code o f Practice f or Concrete Structures f or the Storage o f Liquids) provides guidelines f or the
analysis and design of liquid sto rage tanks. The four sections o f the code are titled as f ollows.
Part 1: General Requirement
Part 2: Reinforced Concrete Structures
Part 3: Prest ressed Concrete Structures
Part 4: Design TablesThe fo llowing types of boundary conditions are considered in the analysis of the cylindrical wall.
a) For base: fixed or hinged
b) For to p: f ree or hinged or f ramed.
1)For base
Fixed: When the wall is built continuous with its f oot ing, then the base can be considered to be f ixed as the
f irst approximation.
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Hinged: If the sub grade is susceptible to set tlement, then a hinged base is a conservative assumption.
Since the actual rot ational rest raint f rom the f oot ing is so mewhere in between f ixed and hinged, a hinged
base can be assumed. The base can be made sliding with appropriate polyvinyl chloride (PVC) water-stops
f or liquid tightness.
2) For top
Free: The top of the wall is considered f ree when there is no rest raint in expansion.
Hinged: When the top is connected to the roo f slab by dowels f or shear transf er, the boundary condition is
considered to be hinged.
The hydrostatic pressure o n the wall increases linearly f rom the to p to the bot tom of the liquid o f maximum
poss ible depth. If the vapour pressure in the f ree board is negligible, then the pressure at the to p is zero .
Else, it is added to the pressure o f the liquid throughout the depth. The f orces generated in the tank due to
circumf erential prestress are oppos ite in nature to that due to hydrost atic 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 = CTw H Ri
The bending moment in the vert ical direction is given as
M = CMwH3
The shear at the base is given by the expression V = CVw H
Where,
CT = coeff icient f or hoop tension
CM = coef f icient f or bending momentCV = coeff icient f or shear
w = unit weight o f liquid
H = height of the liquid
Ri = inner radius of the wall.
The values of the coef f icients are tabulated in IS:3370 1967, Part 4, f or various values o f H2/Dt, at
dif f erent depths o f 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, f or two sets of boundary conditions are
illust rated. The roo f can be made of a dome supported at the edges o n the cylindrical wall. Else, the ro of
can be a f lat slab suppo rted o n columns along with the edges. IS:3370 1967, Part 4, provides coef f icientsf or the analysis of the floo r and roof slabs.
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Design steps
Calculate diameter and height o f water tank
Assumed suitable thickness
Calculate designed constants
Calculate hoop tensio n, maximum bending moment by using IS 1370 part IV.
Check the assume thickness with given permissible values o f tensile st resses o f concrete in direct
tension f or the given grade of concrete.
Actual circumf erential prestress i.e. actual direct compressive stress (f c)
Provide circumf erential steel , Provide vertical steel
Check f or ultimate co llapse and cracking Non prestressing steel /untensioned steel
Design base slab
Draw detail
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 o f tank f loo r sho uld be
taken either 150mm or equal to the wall thickness(if greater than 150mm) f or RCC water tank and minimum
thickness f or priestesses concrete water tank is 120mm.We consider tank capacity f or bo th the cases (i.e.RCC & Priestesses) reimaging from 1000 m3 to 9000 m3. f or both the grade o f 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
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CAPACITY GRADE OFCONCRETE
COST OF P.C. WATERTANK
% OFCOST
COST OF R.C. C.WATERTANK
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 M40 1169380 -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 t hat prestressed concrete tank is econo mical than RCC water
tank and vice--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 o f % of saving for given capacity with given grade of concrete(M40)
Figure 5 Variation o f % 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 f irm ground with the cost
of Prest ressed concrete water tanks. In India at least , mos t o f the small & medium sized water tanks are
constructed in RCC. Senior engineers and those in the know maintain that prest ressed concrete water
tanks are not worth t rying f or smaller capacities. Besides cost , ot her reason may be that prestressed
concrete const ruction involves skilled labor & supervision. Furthermore, prest ress ing is a closely guarded
technology in this country & info rmation is not available that easily.
There is no clear-cut def inition of Medium Size. The thumb rule passed on in the f ield f rom one
generation o f engineers to the next, f ixes a value around 10 lac liters. Theref ore, this study encompasses
tanks f rom 10 lac liter capacity to 90 lac liter capacity. A couple of cases o f both varieties were designed
manually. Design & Est imation programs were developed in MS EXCEL f or both RCC & Prest ressedconcrete. The programs were f inalized af ter a number of trial runs & corrections.
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Results obtained are compiled in f igures numbered 1 to 5 & Table numbered 3. D/H ratio f or all the tanks is
maintained at 4 based on the recommendations of the Preload Engineering Company of the US, a world
leader in the f ield of prest ressed concrete water tanks. It should be noted that an increase in tank wall
thickness results in decreased f lexural steel in case o f RCC. However, in case of prest ressed concrete, an
increased thickness leads to a greater prestressing f orce & consequently more prest ressing steel. Thus,
increased thickness leads to increased cost in case o f prestressed concrete.
Table3 presents the to tal cost of each tank along with the % dif f erence. + means cost lier prestressing &
- means cheaper prestressing. As the tank capacity increases, the cost of tank increases. But the conceptof economics o f scale holds goo d i.e. the cost of a tank of 20 lac liter capacity is less t han double the
cost o f a tank o f 10 lac liter capacity. Similarly, the cos t o f a tank of 90 lac liter capacity is less t han 9 times
the cos t o f a tank of 10 lac liter capacity. It can be clearly established that the grade of concrete hardly
makes any dif f erence in the cost ing. Because o f its nature, the water tank design is never an impending or
boundary line design. The f actor o f saf ety is high & the actual stresses are much lower than the
permissible ones. An increased permissible stress f or a higher grade of concrete hardly makes any
diff erence to the f inal outcome.
Finally, a study of the same Table3 conf irms t hat 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-f olds f or higher capacities. Thickness in f act seems to be an
important criterion even for prestressed tanks. An increased thickness leads to an increased prestressing
f orce. More s teel is required to generate this higher prestressing f orce resulting in higher cost .
CONCLUSION
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%.
7/29/2019 Engineeringcivil.com-Economics of RCC Water Tank Resting Over Firm Ground Visavis Prestressed Concrete Water
15/15
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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.