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The Making of
KUDANKULAM NUCLEAR POWER PLANT
INTRODUCTION
HIGHLIGHTS IN BRIEF
PROJECT OVERVIEW
CHALLENGES
ENCOUNTERED
A TRIUMPH OF HIGH TECH CIVIL ENGINEERING
Introduction:
KEY PEOPLE
In the year 1987 to meet the increasing demand for energy, DAE decided to go in for
large capacity Pressurized Water Reactors In view of the large worldwide operating
EQUIPMENT USED
experience for pressurized water reactors. After detailed evaluation, VVER type
FASCINATING FACTS
along the coast of Gulf of Mannar, 25 km northeast of Kanyakumari in Tamilnadu.
Russian reactors of 1000MWe capacity were chosen to be located at Kudankulam
Kudankulam Nuclear Power Project consists of 2x1000Mwe Water Cooled Water
Moderated Energy Reactors (called VVER – Vada Vada Energy Reactor type 1412, Vada
means Water in the Russian language), which falls under the category of Pressurized
Water Reactor and is the first of its kind being built in India. An Inter-Governmental
Agreement on the project was signed on November 20, 1988 by Prime Minister Rajiv
Gandhi and Soviet President Mikhail Gorbachev. Supplement to Inter governmental
agreement of 1988 was signed between the Indian and Russian Governments in the
year 1988, to implement 2x1000 MWe Kudankulam Nuclear Power Project on
technical co-operation basis.
HCC's expertise in building nuclear power plants
HCC has been in the forefront of construction of Nuclear Power projects and has built
over 50% of India's nuclear power generation capacity. HCC possesses world-class
technical capacities & experience - associated with construction of 4 plants out of 7
(executed/under execution) in India, proof of confidence reposed by NPCIL.
HCC is the first engineering company in India to have all three international certifications for Quality, Occupational Health & Safety and Environment
The details of nuclear capacity built by HCC are as follows:
Rajasthan Atomic Power Project Units I and II (1x 100 MW & 1 x 200 MW) in
year 1971 & 1973. This is India's first indigenously designed Nuclear Power
Plant.
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Narora Atomic Power Plant (2 x 235 MW) in year 1984, this project has won an
award for its Constructional features from the prestigious, American Concrete
Institute.
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Bhabha Atomic Research Center in year 1986
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Kakrapar Atomic Power Plant Units I and II (2 x 220 MW) in year 1990 - won
the Award of Excellence for the most outstanding concrete structure in India, from the India Chapter of
American Concrete Institute in 1991
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Rajasthan Atomic Power Project Units III and IV ( 2x 220 MW) in year 2000
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Rajasthan Atomic Power Project Units V and VI ( 2 x 220 MW) in year 2008
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Project Overview:
HCC was awarded the contract to construct Kudankulam Atomic Power Project Units I and II (2 x 1000 MW) by
Nuclear Power Corporation on 25th February 2002. The project consists of two 1000 MW capacity Water Cooled
Water Moderated Energy Reactors (VVER), which falls under the category of Pressurized Water Reactor and is the
first of its kind being built in India. This type of reactor uses about 4.4% enriched Uranium as fuel. The design of
the plant and supply of all the major equipment is in the scope of the Russian Federation while development of
infrastructure and project construction is in Indian scope of works.
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Russian Organizations are responsible for design, supply of material, equipment and machinery, nuclear fuel,
construction supervision and training of Indian personnel for operation and maintenance.
NPCIL is responsible for land acquisition, infrastructure facilities, civil construction, mechanical and electrical
erection, participating in commissioning and eventually taking over the operations.
The civil works of the entire project was mainly divided into six packages:
Package 1>
Package 2>
Package 3>
C1
C2
C3
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Earth work
Subsoil investigation
Construction of Reactor building and reactor auxiliary buildings and associated
works
Package 4>
Package 5>
Package 6>
C4
C5
C6
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Construction of Turbine Buildings and associated works
Construction of Auxiliary buildings and associated works
Construction of Hydro technical structures and associated works
HCC was responsible for construction of the most challenging Package C3 and Package C6 for the project.
Package C3
Construction of Reactor Building and Reactor Auxiliary Buildings and associated works
The scope of work includes complete civil and structural works of the two reactor buildings along with the reactor
auxiliary and control room buildings.
Reactor Building
The 88 meters tall structure of the main Reactor building has been done with a novel raft design for the reactor
structure. The reactor building raft has a foundation at 8.85 meters below the ground level. The thickness of the raft
foundation is 4.6 meters at the end and 1.6 meters in the middle. The containment base slab is at 1.1 meters above
ground level and 5.35 meters above the foundation which is of 1800mm thick and the total concrete quantity of
this slab is 6000 Cum. The containment base slab supports the core of the nuclear reactor placed in the reactor
cavity at the center of the containment structure.
Inner Containment Structure
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Inner containment wall starts from +5.35 M above ground level and goes up to +43.9 meters as cylindrical
part with a dia of 44 meters.
The hemispherical dome starts from +43.9 meters with radius of 22 meters.
The top of Inner Containment Dome is +67.10 meters.
The inner containment wall is 1200mm thick and outer containment wall is 600 mm. The annular space
between inner containment and outer containment is 2200 mm
A special feature undertaken in India for the first time is a completely steel lined dome of the inner containment
wall and dome for the reactor building. The dome was constructed in three major parts.
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Part I – Liner segment from elevation + 43.9M to elevation +49.5M, was fabricated and erected in 15
segments, similar to cylindrical liner.
Part II – Liner segment from elevation +49.5M to elevation +57.1M was fabricated in 15 segments and preassembled at ground.
Part III – Liner segment from elevation +57.1M to elevation +65.7M was fabricated in 15 segment and preassembled in the ground, inside the dome Part-II assembly area.
Part IV – Small part of the apex from elevation +65.7 to elevation +65.91 was fabricated and erected
separately.
Erection of the Dome:
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The erection of the dome Part-II & III were carried out using 650MT Liebherr Crane.
A circular evener beam of diameter 16.9M weighing 15MT was specifically designed, analyzed by finite
element method, verified, and fabricated.
There were 15 slinging points from the dome parts to the evener beam and 4 slinging points from the
evener beam to the crane hook.
Before erection of dome Part-II, dome Part-III was lifted and matched with Part-II on the ground level itself,
and connecting plate welded to the part-II portion.
The crown portion from EL +65.7 to EL +65.91 was fabricated and erected separately.
The fabrication and erection of the dome is carried out with in strict tolerance limits.
Another special feature of the construction is the Unbounded Prestressing system adopted for a Reactor
Containment Structure for the first time in the world and HCC is the first engineering company to execute it. The
prestressing system use tendons consisting of 55 strands of 15.7mm diameter of high strength steel wires. There
are 68 numbers of horizontal tendons, circular in plan and 60 numbers of inverted U-shaped vertical tendons which
are anchored at both ends of the stressing gallery which is a circular corridor located on the ground level of the
Reactor building. 219.1mm steel pipes are used as the tendon ducts for the inverted U shaped vertical tendons
and 200mm diameter dross Bach ducts are used for the horizontal tendons. Generally use of a prestressing
system reduces the thickness of the inner containment wall while offering additional strength. In the case of the
unbounded system the advantages are
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High efficiency of pre-stressing is possible due to very low friction co-efficient (0.05). This may help in:
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Possibility of using tendons of longer length
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Possibility of using less no. of tendons
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Possibility of higher spacing of tendons
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More uniform stress in the tendons and in concrete due to low variation of force along the strands.
HCC team has been instrumental in modifying & refining the techniques and procedures for strand threading and
grouting to achieve the required perfection by study and analysis of problems during a full scale mock-up of a
horizontal circular tendon, which has been accepted by AERB, India.
Unique features of project:
The Main Reactor Buildings are the heart of each unit designed to produce 1000 MW power each – by far the
largest Reactors ever built in India. These are not only the largest but the first to have the following construction
features
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The inner and outer containment structures have complete hemispherical dome. The outer
containment dome is further protected by a PHRS (Passive Heat Removal System) dome.
The inner containment floor, wall and dome are completely lined with steel liner on the inner face.
The inner containment also has 45 steel brackets; over which 15 steel beams of box section
ultimately supports 30 rails. This rail of 21m radius is provided for supporting a 350t capacity Polar
Crane.
The inner containment structure is pre-stressed by 55C15 type tendons, each tendon constituting
55 HDPE sheathed strands of 15.7mm nominal diameter. This is the first time in the World that an
un-bonded pre-stressing system has been adopted for a reactor containment
Overview of the VVER-1000 Reactor operations:
The reactor vessel for VVER-1000 plant is designed to contain the vessel internals and fuel assemblies of the core.
The reactor along with control rod drive units has overall height of 19 meters and diameter of 4.5 meters. It is a
vertical cylindrical container made of 190mm thick high purity low alloy steel ring forging, welded together and
cladded inside with stainless steel.
The reactor is placed in a concrete pit inside the containment. The reactor coolant system (RCS) transfers the heat
generated in the reactor core to the steam generators where steam is produced to drive the turbine-generator. The
borated demineralised water coolant of RCS also acts as a neutron moderator and reflector and as a solvent for the
neutron absorber. The RCS pressure boundary provides a barrier against the release of radioactivity generated in
the reactor and is designed to ensure a high degree of integrity throughout the life of the plant.
The turbine is designed to operate at 3000rpm on saturated steam in conjunction with VVER-1000 reactor having
thermal output of 3000MW(th). The rated output at the generator terminal will be 1000MW based on cooling water
temperature of 32oC and steam dryness factor of 0.995. The electricity generated will be supplied to the southern
grid.
Challenges encountered in project execution
Kudankulam Nuclear Power Plant involved many new features and challenges which were not anticipated earlier.
Fabrication and erection of liners for Inner Containment
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Detailed planning was required to fabricate the liners for the 44m diameter walls.
The cylindrical part of liners to cover a height of 38.5m, have been made in 8 tiers with 15 segments.
The maximum height of one tier is about 6.5m.
Each segment is made out of 6mm thick steel sheet stiffened by structural sections on the back side.
The liners were fabricated to stringent dimensional tolerance of - 0 / +10mm radius and all welded joints
were subjected to 100% leak tightness test by Vacuum Box and 20% Ultrasonic examination.
In order to take care of correct fabrications, jigs were fabricated, inspected and cleared for each type of
panel for mass production.
A massive fabrication shop of 15m x 57m was set up with 15mt EOT crane.
Annexed shop for Grit Blasting and Painting was set up.
To facilitate transfer of the large fabricated panels to grit blasting & painting shop, in-house tailor-made
transfer trolleys on rails were erected.
View of Inner Containment Inside steel wall liner and Outer Doka Climbing shutters
Erection of Dome Liners
The containment dome liner is of hemispherical shape of 22m radius, made out of 6mm thick steel plates with
circumferential and radial stiffeners on the outer side.
Part I of the dome liner of 5.60m height was assembled of 15 segments in-situ.
Part II of height 7.6m & Part III of height 8.8m were assembled at ground level, lifted and then placed in the
position.
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Dome Part II & III ground assembly
Fit up mock up of Dome Part III with part II at ground level
Lifting of Part II Dome Liner
This part of truncated hemispherical shape, weighing 90 tones, was lifted and placed in position over the existing
Part I dome of RB-1 on 17th July 2006. 650 tones capacity crane was used for erection. The special features of this
erection work are as follows:
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This is the first time in India such a huge dome was fabricated and erected. There was no direct experience
available in the country.
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Considering the low stiffness and open shape, it has become essential to ensure that the dome does not
distort during lifting. It has also become essential to balance the structure and restrict the possible sway of
the structure during lifting.
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Considering the Safety of the crane against wind load acting on the dome, the erection had to be carried out
in relatively calm weather. The acceptable wind velocity was 35 Km/Hr maximum. But during this time of
the year, there was wide fluctuation of wind speeds in this coastal area and quite often it goes up to 60
Km/Hr.
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However, several steps were taken to take care of the above problems, at the planning and execution stage.
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A no-load mock-up of the 650 tones crane was carried out in the initial stage to locate the starting position of
the crane and the dome and the vertical clearance required for taking and placing to position. The sequence
of lifting, marching and swinging was meticulously worked out well in advance to avoid any unforeseen
problems.
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An evener beam of 16.9m diameter was designed and fabricated by HCC for controlling distortion and sway
of the dome. Safety of the evener beam was checked with advanced analytical tools using finite element
technique.
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The evener beam is connected to the main hook of the crane with 4 slings of 80mm size.
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In turn the dome is connected to the evener beam with 15 slings of 38mm size. These slings have been
specifically made for this job and load tested, before its use, and certified by a third party agency.
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This evener beam as well as the sling hooking points was checked for integrity by carrying out nondestructive tests after load testing.
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Two of the four tower cranes at RB-1 were lowered to below 53m level to ensure adequate clearance from
the bottom of the dome as well as from the mast and boom of the crane during the swinging and lowering
operation.
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The time of erection was decided after studying the hourly wind speed variation data available from the
Project Meteorological laboratory. The afternoon period from 2PM to 7PM was found to be most favorable.
However, continuous monitoring of wind speed was done during the erection.
Dome Part II erection in progress
Time Consumed
Actual lifting was started at 4PM and the placing in position including arresting of support points, was completed
by 6PM - in just two hours. Just after 16 days from the date of lifting, i.e. on 2nd August 06, the complete fit-up
and welding of dome Part II to the dome Part I was completed.
Lifting of Part –III Dome Liner
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This part of hemispherical shape, weighing 180 tones (including 25 tones weight of the sprinkler system
fixed on the inner face of the liner) was lifted and placed in position over dome Part II on 25th August, 2006.
The methodology followed was similar to erection of dome Part II, except the following features.
This part was load tested after fixing of the sprinkler system, and the integrity of the evener beam and the
slinging points were again checked by non-destructive tests (including UT, RT and DPT)
This time the available meteorological data indicated that the wind speed would be low in the morning,
between 6AM to 9AM.
The completion of welding of Part II liner and checking of its dimensions in-situ had to be ensured before
lifting Part III.
Protocols related to satisfactory installation of the Polar Crane within the containment had to be completed
by NPCIL before allowing this erection.
Dome Part III erected over Part II
Time Consumed
The actual lifting operation started at 07:40AM and the dome was in position for fit-up to Part II by 9AM. Total
duration was 1hr 20min.
Passive heat removal system structure (PHRS)
This was indicated as a simple structure with a tertiary dome starting from a cantilevered slab at 52.87m and going
up to 81.00m & PHRS enclosure. However when detailed drawings were given the work involved complex works
of rib walls, slabs and load requirement for the slab which involved fabrication and erection of about 650MT of
special staging, to support the slab and retain the same till some design considerations were met.
The main features of this structure were:
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Structure starts at 36.00m El cantilevered from Outer-containment wall
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Cantilever portion : 7.70m
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Thickness of slab is : 600mm
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Circular wall from the edge of the cantilever starts at 36.60m and up to 52.27m.
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Partial 600mm slab connected from outer-containment wall to outer wall of PHRS at 43.20m.
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Rib walls starts at 43.20m above the slab and connected to outer wall of PHRS.
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Load on the staging for the below portion of outer wall is to be considered PHRS wall up to +52.27m and
slab load at two elevations.
Staging for 36.0m PHRS Slab (north side View)
Staging for 36.0m PHRS Slab & Outer wall (East Side view)
Polar Crane
The 350ton capacity polar crane runs on a circular railbeam assembly on brackets fixed on the Innercontainment wall. The fabrication of brackets and beams
and erection of the same posed real challenges. The
concerned item says “fabrication & erection of brackets
and beams for crane assembly“. However when detailed
drawings were issued the complexity involved and
amount of details required to be attended, as well as the
complex sequence turned this job into “Precision
engineering work”, totally different from what was
anticipated.
Polar Crane Main Beam assembly over supporting structures
Package C6
Construction of Hydro technical structures and associated works
The Hydro technical structures at KKNPP provide necessary cooling water required for the nuclear plant operation
as well as its discharge after cooling the plant loads. To avoid silt, the sea water is drawn at a distance of 1.2 km
away from the shore at 9.05 meter depth below the sea level from a caisson structure placed at the south tip of
two breakwater dykes. Water was then transported by gravity through intermediate structures to the fore bay of
the pump house complex at 13 meters below sea level. The intermediate structures consist of sea water intake
structure with a fish protection system, three tunnels each for carrying the sea water to two pump houses from
where the water is pumped to condensers in the turbine building through pressure pipelines.
Scope of work includes the following structures Design & Construction of Coffer Dam cum Temporary Dyke and Removal
Construction of RCC Caisson for entry of sea water
Construction of Permanent Breakwater structure
Sea water Intake Structure and Fish Protection facilities
Sea water Inlet Pipeline
Fore-Bay
Bridge
Main Pump House and Essential Load Pump Houses
Pressure Pipelines
Essential Load Pipe Tunnel
Siphon Wells
Discharge Channel
Sea Water Outfall
Chlorination Plant
Shore Protection
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Schematic Sketch of Intake Structure
Functional description of various hydraulic structures
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Concrete cellular structures called caissons (4 nos) approximately weighing above 3000 MT each will be
sunk in the mouth of the breakwater to draw water.
Breakwater dyke of 2.0 km, rectangular in plan in the form of a pool located about 300m away from the
shore line is constructed. Water is drawn at the extreme southern end of breakwater and let into the inlet
pipes at the northern end. The shoreline is stabilized and erosion is prevented by Construction of Shore
Protection Structure of 1.5km length.
Intake and Fish Protection Structures are located in the northern end of the breakwater dyke. This
structure creates waves and provides compressed air inside the water to generate an upward lift, which
makes the fishes to travel in the uppermost water surface and get ejected to sea by hydraulic ejectors.
Sea Water Inlet Lines laid below the sea bed near intake structures convey water by gravity to the fore bay
structures on the shore and then into the pump house. The water is then pumped up to condensers in the
turbine building through pressure pipelines
Pump house complex housing the main pumps for condenser cooling and also essential load pumps. It is
connected to the fore bay for water intake and discharge channels, which receive hot water from the
condenser and discharge it in to the sea.
After cooling the condensers, the hot water will then be discharged into the sea near the shore through
discharge channels constructed below the lowest low water level inside the sea.
Construction sequence:
Temporary Dyke
Since the major hydro technical structures were located near the shore and extend up to 1.2 kms inside the sea
from the shoreline, the construction of a temporary dyke became the prime requirement. The temporary dyke
acted as a water tight barrier under dry conditions and facilitated the construction of pump houses, fore bay, intake
structure, fish protection structure, bridges and caisson. Its approx length is 1.2 kms and consisted of two rock fill
bunds with a central core of clay. Sheet pile was also inserted to prevent the seepage of Sea water into the dry
portion.
Pump Houses and Chlorination Plant
The two pump houses providing the cooling water to two reactors are situated on the northern side of the intake
structures. The pump house complex has a length of 129.9 mts and is divided into 7 grids from west to east and a
width of 47.8 mts divided into 3 grids (Grid A, B & C) from south to north. The main pump house houses 3 pumps
of non-essential loads & 6 pumps of condenser cooling type. The Chlorination plant is located in between the two
pump houses along the shoreline and is used for production of hypo-chlorate.
Pump House Structure along with fore bay
Concrete Volute
A concrete volute has been provided to feed water into the condenser cooling water (CCW) pumps from elevation
– 10.5mts -7.0mts, just vertically below the pump. There are 6 nos of concrete volute in each pump house. It is the
transition of the suction cavity from rectangular section in the vertical plane (i.e. water intake) to circular section in
the horizontal plane (i.e. the pump side), the shape being adjusted at every 15o along the transition turning upward.
This provides a smooth suction to CCW and avoids possible damages due to turbulence. Special formwork
concrete was made of steel with a conical shape having 90o bend upward. The shutter was supported at top with
the help of a steel truss fixed to the top of the walls. The segments were manufactured and joined together by
welding to make larger panels which were in turn joined by bolting in-situ. Each volute concreting was carried out in
a single pour.
Volute Construction in Pump houses
RCC Inlet Pipelines
RCC inlet pipelines convey water from intake structure to fore bay across a length of 277 mts and level difference
of 900 mm by gravity flow. It's a rectangular shaped structure in cross section having 3 cavities of 4.10 mts and is
used for sea water transportation.
Intake Structures and Fish Protection system
At the northern most end of the breakwater
intake structures a fish protection system were
constructed. This consisted of 3 sets of Oogee
structures which prevent the entering of small
fish into inlet tunnels connected to the pump
houses. The natural tendency of fish to flow
against the water pressure has been envisaged
in the design. By creating waves and providing
compressed air within the water, an upward lift
is created carrying the fish in the uppermost
water surface and ejecting them in the sea by
hydraulic ejectors.
For this purpose Oogee structures were constructed consisting of 6 nos of vertical gates and 6 nos of inclined
gates. This helps in closing the entry of sea water from the breakwater portion during the time of maintenance of
tunnels. To prevent the formation of algae, system 1 paint (Coal Tar Epoxy paint of 350 micron) has been used up to
the splash level and above that System 2 paint (Water proofing acrylic polymer) which acts as an anti-coagulant has
been applied.
Breakwater Dyke
This is constructed to protect the intake and fish protection structure located at the northern end from the sea
disturbance and positioning of caisson at its southern end. The plan dimension of the structure at the centerline is
approximately 900m x 250m. The bottom sea level is from – 4.0 m to -13.0 m mean sea level. The dyke has a top
elevation of + 8.0 m with side slopes 1:2. It consists of 2 sections – sheet pile section and the non-sheet pile
section. The sheet pile section extends up to 500 mts on each side.
Large quantity of Tetrapods (28,360 nos) of three different types (5T, 13T, 20T) were used to give stability to the
breakwater dykes from rough sea conditions. The lighter tetrapods were placed closer to the shore line whereas
the heavier ones are placed towards the sea. Total concrete used in construction of these tetrapods is 1,09,000
Cum. Water base membrane curing compound was applied on the surface after de-molding for better curing, due
to the typical shape and to conserve water.
Arms of Breakwater Dyke along with other Hydraulic Structures in 2008
Sea water intake Caisson
Four Caissons are placed at the southern tip of breakwater dykes for sea water intake. Out of these, two are used
as water passage and two are adjoining units. Water passage units are 46 x 15 x 12.45 mts in dimension (as large
as a four storey residential building) and 3400 MT in weight. The adjoining units are 36 x 15 x 12.5 mts in
dimension and 2300 MT in Weight. These caissons are constructed in the temporary dyke area. Corrugated
asbestos sheet are provided beneath the caisson bottom slab to avoid sticking of the caisson raft to the bed. The
outer surface was protected by the use of Coal Tar Epoxy paint of 350 microns for the portion beneath the sea and
Water proofing acrylic polymer paint above splash level.
After construction, the temporary dykes are breached to allow the water to come inside this area to float these
huge structures. Then these floating structures were towed to the desired location at the southern tip of
breakwater dykes and placed in position. The sea bed was prepared at this position by leveling the sea bed using
controlled underwater blasting. After placing the Caissons, concrete was poured in to the upper hollow
compartments to achieve the desired weight so that they are not displaced by the waves.
The water intake channels in the caissons are provided at a depth of 9.50 meters below sea level which prevented
biomass and aquatic life from entering the intake zone.
Caisson Structure: Water Passage unit
Caisson at dry dock
Challenges encountered in project execution
Construction of Temporary Dyke
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The Construction was started using end on method and completed by meeting of both arms at the middle of
the length.
Dewatering was started after completion of the temporary dyke
To control the heavy seepage additional clay bunds and sand filled gunny bags were used where excess
seepage was seen.
To overcome this problem and to arrest the seepage Z type sheet piles of 8.5 mm thickness and 49 kg/m
weight were driven through the clay core to the bed till refusal.
After completion of sheet pile driving, the temporary dyke could be dewatered successfully
The precision and accuracy of design considerations was proved when the tsunami occurred in December
2004
Floating, Towing & grounding of Caissons – Methodology
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After completion of all hydraulic structures within the area enclosed by the temporary dyke, the dyke was
breached, letting the sea water come inside the dyke area, facilitating the floating of caissons.
The valves were opened to enter the compartments
With this, the water level inside and outside the caisson was automatically kept at the same level,
preventing the caissons from floating.
The towing path for the caissons was pre-determined and to obtain the requisite draft along the path,
dredging was carried out, by controlled underwater drilling and blasting methods.
Weather forecasting reports, depicting the wind and wave condition was obtained from Met consultancy,
Switzerland.
The bed preparation at the desired location was done by using graded stones.
The caisson was towed to the desired location using winch operation.
Dead man anchors of 15t and 30 T in the breakwater dyke and marine rock anchors of 100T capacity at the
south of the caisson placing location inside the sea bed were used to hold up the caisson during the winch
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operation.
The caisson was towed to the desired location, the co-ordinates were ensured from total station and the
grounding operation was initiated by ballasting of caisson compartments in line with the operating manual.
After complete grounding of the caisson, co-ordinates were rechecked for proper positioning and ballasting
was done with tremie concrete, replacing the water ballast with concrete ballast for further stability.
After filling the caisson units by concrete ballast , RCC walls all along the periphery of the caisson units were
raised to the required levels (+ 7.33 )
RCC slab was then constructed which provides a pathway all along the Breakwater Dyke.
Caisson casting yard at Break Water
Towing of Caisson unit
Towing of Caisson unit
De-ballasting i.e. floating of Caisson unit
Placing of Caisson unit at Chainage 1045 S and subsequent joining of Breakwater Arm
All 4 caisson units placed at its designed location
Bird's Eye View of C6 Offshore works after completion of Caisson placement
Conclusion
Construction of the Hydraulic structure was a challenging task, the execution of which represents precision and
world class quality. The Hydraulic structure at KKNPP stands out for its magnitude of the caisson structure,
massiveness of the breakwater dyke and complex constructions – be it the volute in the pump house or Oogee in
the intake structure or RCC inlet pipelines or the huge number of tetra pods casted and placed.
Towing of the caisson structure of such a large magnitude was in itself a challenging task considering the rough
weather and sea conditions faced at site, exemplifying the determined efforts of our HCC team.
TEAM KKNPP
Over 3500 Officers and Workers were employed to work on the project. They stood together as a Team to achieve
their mission of completing the project on schedule. Professionals, Engineers, Technicians, Staff and Workmen
have been involved along with consistent support from HO Departments in specialized tasks for the construction
of structures of Reactor Building Units 1 & 2 and for the construction of the Breakwater project and caisson
structures.
Lingual and cultural differences were not obstacle to the unity of all the members of Team KKNPP. The dedication
and enthusiasm of each one helped achieve the mission and shaped the execution of this complex and first of its
kind Engineering Challenge. This has underlined Team KKNPP's 'Unity in diversity'.
Few lines of Amanda Bradley curtly describes the spirit of Team KKNPP
Do not follow me
I may not lead
Do not go in front of me
I may not follow
Come, let us walk together
and reach the destination
Team KKNPP walked together and reached the destination.
Major Equipment Deployed at KKNPP Site
Sr
Description
Capacity
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1
Concrete Batching Plant
90 & 60 Cum/hr
4 Nos
2
Concrete Pump
90 & 60 Cum/hr
6 Nos
3
Stationary placer boom
42mtr
6 Nos
4
Mobil boom Placer 36 mtr
90 Cum/hr
2 Nos
5
Super Swing concrete Placer
90 Cum/hr
2 Nos
6
Flake ice plant
20 TPD
4 Nos
7
Chilling Plant
125TR
1 Nos
8
Crushing plant
250/125/80 TPH
3 Nos
9
Grout pump
10 Cum/hr
1 No
10
Transit Mixer
6 Cum
22 Nos
11
Crawler Crane
400 / 150 / 75 / 40 MT
7 Nos
12
12Ton Tower Crane
HUH 92.60 with 60m reach
8 Nos
13
10Ton Tower Crane
HUH 60.00 with 60m reach
4 Nos
14
Tug
20ton & 10 Ton Bolerd Pull
2Nos
Quantities of various items executed
Sr
Item Description
Unit
Total Quantity
1
Concrete (Normal)
Cum
7,30,000
2
Concrete (Heavy)
Cum
11,000
3
Reinforcement
Tons
55,000
4
Form Work
Sqm
7,20,000
5
Structural Steel & Embedded Parts
Tons
17,500
6
Water Proofing Membranes
Sqm
3,10,000
7
Tetra Pod Casting & Placing
Nos
28,500
8
Armour, Core , filter aggregate placing
Tons
30,00,000
9
Paint Application
Sqm
5,80,000
Peak quantum of various items executed
Sr
Item Description
Unit
Peak Quantity executed in a month
1
Concrete (Normal & Heavy)
Cum
35,000
2
Reinforcement
Tons
1,200
3
Form Work
Sqm
22,000
4
Structural Steel & Embedded
Tons
780
Quantum of Major material purchased
Sr
Name of the Material
Quantity Procured
1
Cement
2,16,000 Tons
2
Rebar
60500.00 Tons
3
Structural Steel
21000.00 Tons
4
Paints
5
Water Proofing membranes
6
Heavy Aggregate
3,80,000 Lit
3,20,000 Sqm
43000.00 Tons