Nuclear Power Plant.ppt

Nuclear Power Plant
Nuclear Power Plant
With Case Study
Presented by:
Sambhaji P. Harwandkar
As a Course of
Advanced Construction Techniques
Under the Guidance of
Prof. M.Y.Mhaske
A Seminar On

Nuclear Power Plant
Contents
 Introduction
 Reactor Types
 Life Cycle
 Fuel Resources
 Solid Waste
 Economy
 Capital Cost
 Risk

Nuclear Power Plant
Contents
 Accidents Or Attacks
 Air and Water Pollution
 Health Effect on Population Near NPP
 Nuclear Proliferation
 Advantages and Disadvantages of NPP
 Working of Nuclear Power Plant
 Advanced Construction Techniques
 Case Study

Nuclear Power Plant
Introduction
 NPP Provides About 17% of the World’s
Electricity & 7% of global energy
 Decline due to accidents of three Mile Island
in 1979 & of Chernobyle in 1986
 Renewed interest due to Both dwindling oil
reserves & global warming

Nuclear Power Plant
Introduction
origin
 First successful experiment in 1937 in Berlin by
German Physicists Otto Hahn, Leise Meitner and
Fritz Strassman
 first self-sustaining nuclear chain reaction obtained
by Enrico Fermi in 1943
 Electricity generated for the first time by a nuclear
reactor on December 20, 1951 near Arco, Idaho
 June 27, 1954, the world's first nuclear power plant
for commercial use at Obninsk

Nuclear Power Plant
Introduction
Development
 Nuclear capacity rose relatively quickly
from less than 1 GW in 1960 to 100GW in
the late 1970s and 300GW in the late
1980s
 1980 onwards movements against Nuclear
power as a result of Rising economic
costs, falling fossil fuel prices, fear of
possible nuclear accidents and on fears of
latent radiation

Nuclear Power Plant
Introduction
Current and planned use
 In 2005, there were 441 commercial
nuclear generating units throughout the
world, with a total capacity of about 368
gigawatts
 111 reactors (36GW) have been shut down
 80% of reactors are more than 15 years
old
 In 2004 in United States, there were 104
commercial nuclear generating units 20
percent of the nation's total electric
energy consumption
 In France, as of 2002, 78% of all electric
power was generated by nuclear reactors

Nuclear Power Plant
Reactor Types
Current Technology
 Nuclear fission reactor
(a) Pressurized water reactors (PWR)
(b) Boiling water reactors (BWR):
(c) RBMKs(Russian Acronym for "Channelized Large Power
Reactor“)
(d) Gas Cooled Reactor and Advanced Gas
Cooled Reactor (GCR)
(e) Critical water reactor (CWR)
(f) Liquid Metal Fast Breeder Reactor
(LMFBR)
 Radioisotope thermoelectric generator

Nuclear Power Plant
Reactor Types
Experimental Technologies
 Integral Fast Reactor
 Pebble Bed Reactor
 Sub critical reactors
 Controlled nuclear fusion

Nuclear Power Plant
Life cycle
Nuclear fuel cycle begins when uranium is mined,
enriched and manufactured to nuclear fuel which is
delivered to a nuclear power plant. After usage in the
power plant the spent fuel is delivered to a reprocessing
plant or to a final repository for geological disposition. In
reprocessing 95% of spent fuel can be recycled to be
returned to usage in a power plant.

Nuclear Power Plant
Fuel resources
 Extraction from seawater or granite
 Use thorium as fission fuel in breeder
reactors
 fast breeder reactors use Uranium-238
(99.3% of all natural uranium)
 Use of deuterium, an isotope of hydrogen

Nuclear Power Plant
Solid waste
 Spent fuel composed of unconverted uranium,
transuranic actinides (plutonium and curium )
 Average nuclear power station produces 20-30
tonnes of spent fuel each year
 Must be stored in shielded basins of water, or in
dry storage vaults or containers until its
radioactivity decreases to safe levels
 Nuclear power, radioactive wastes comprise less
than 1% of total industrial toxic wastes

Nuclear Power Plant
Economy
Opponents of nuclear power claim that any of
the environmental benefits are outweighed by
safety compromises and by the costs related to
construction and operation of nuclear power
plants, including costs for spent-fuel disposition
and plant retirement. Proponents of nuclear
power state that nuclear energy is the only
power source which explicitly factors the
estimated costs for waste containment and plant
decommissioning into its overall cost, and that
the quoted cost of fossil fuel plants is
deceptively low for this reason.

Nuclear Power Plant
Capital costs
 The cost per megawatt for a nuclear power
plant is comparable to a coal-fired plant
and less than a natural gas plant
 In Japan and France, construction costs
and delays are significantly less because of
streamlined government licensing and
certification procedures
 In France, one model of reactor was type-
certified, using a safety engineering
process similar to the process used to
certify aircraft models for safety

Nuclear Power Plant
Risks
 long term problems of storing radioactive
waste
 severe radioactive contamination by an
accident
 proliferation of nuclear weapons

Nuclear Power Plant
Accident or attack
 Threat of a nuclear accident or terrorist
attack
 Fusion reactors have little risk since the
fuel contained in the reaction chamber is
only enough to sustain the reaction for
about a minute, whereas a fission reactor
contains about a year's supply of fuel
 nuclear waste can be released in the event
of terrorist attack

Nuclear Power Plant
Air and water pollution
 Nuclear generation does not produce
carbon dioxide, sulfur dioxide, nitrogen
oxides, mercury and other pollutants
associated with the combustion of fossil
fuels
 Fission reactors produces gases such as
iodine-131 or krypton-85
 Nuclear reactors require water to keep the
reactor cool

Nuclear Power Plant
Health effect on population near
nuclear power plants
 No evidence of any increase in cancer
mortality among people living near nuclear
facilities
 Aside from the immediate effects of the
Chernobyl accident, there is continuing
impact from soils containing radioactivity
in Ukraine and Belarus

Nuclear Power Plant
Nuclear proliferation
 civilian nuclear program can be used to
develope nuclear weapons. This concern is
known as nuclear proliferation
 Enriched uranium used in most nuclear reactors
is not concentrated enough to build a bomb
(most nuclear reactors run on 4% enriched
uranium, while a bomb requires an estimated
90% enrichment)
 breeder reactor designs such as CANDU can be
used to generate plutonium for bomb making
materials

Nuclear Power Plant
Advantages of NPPs are:
 Essentially no greenhouse gas emissions
 Does not produce air pollutants such as carbon
monoxide, sulfur dioxide, mercury, nitrogen
oxides or particulates
 The quantity of waste produced is small
 Small number of accidents
 Low fuel costs
 Large fuel reserves
 Ease of transport and stockpiling of fuel

Nuclear Power Plant
Disadvantages are:
 Nuclear waste produced dangerous for
thousands of years
 Consequences of any accident may be
catastrophic
 Risks of nuclear proliferation associated with
some designs
 High capital costs
 Long construction period, imposing large finance
costs and delaying return on investment
 High maintenance costs
 High cost of decommissioning plants

Nuclear Power Plant
Activities involved in construction of
nuclear power plant are:
 Excavation
 Reinforced concrete placement
 Material and component shipping
 Inventory control
 Modularization
 Steel structure erection
 Vessel tank, piping and pipe support installation
 Electrical instrumentation and control installation
 Testing and startup
 Management of documentation design information

Nuclear Power Plant
Working of Nuclear Power Plant

Nuclear Power Plant
Working of Nuclear Power Plant
The method they used to regulate the
temperature of the reactor was to insert
heat-absorbing rods, called control rods.
These control rods absorb heat and
radiation. The rods hang above the
reactor, and can be lowered into the
reactor, which will cool the reactor. When
more electricity is needed, the rods can be
removed from the reactor, which will allow
the reactor to heat up

Nuclear Power Plant
Advanced construction
Techniques
 Steel-Plate Reinforced Concrete
Structures
 Concrete Composition Technologies
 Fiber Reinforced polymer rebar
structure
 High Deposition Rate Welding
 Robotic Welding
 3D Modeling

Nuclear Power Plant
Advanced construction
Techniques
 Positioning Applications in Construction
 Open-Top Installation
 Pipe Bends vs. Welded Elbows
 Precision Blasting/Rock Removal
 Cable Pulling, Termination and Splices
 Prefabrication, Preassembly, and
Modularization
 Construction Schedule Improvement
Analysis

Nuclear Power Plant
 A steel-concrete-steel composite structure
is constructed by placing concrete
between two steel plates
 Studs welded on the inner surface of the
steel plates are embedded in the concrete
to tie the concrete and steel plates
together
 This method of erecting reinforced
concrete structures was first used in 2002
in the construction of an auxiliary building
at the Kashiwazaki-Kariwa 6 and 7 nuclear
power plant site in Japan
Steel-Plate Reinforced Concrete Structures

Nuclear Power Plant

Nuclear Power Plant
 The construction schedule is shortened
 Reduced labor cost
 Require less quantity of steel
 Erection & removal of formwork avoided
 deformation capacity for the SC reinforced
concrete structure is 1.5 times greater
than for an RC reinforced concrete
structure
 Easily dismantle with less cost
Benefits:

Nuclear Power Plant
0
5000
10000
15000
20000
Reinforced
Concrete
Steel Plate
Reinforced
Concrete
Formworker
Rebar Placer
Scaffolding other
construction
Ironworker
Others
Comparison of the On-Site Man Power Requirements

Nuclear Power Plant
0
10000
20000
30000
Reinforced
Concrete
Steel Plate
Reinforced
Concrete
Column/ Shear
Wall
Beam/slab
Partion Wall
Others
Comparison of the Quantity of Steel Requirements

Nuclear Power Plant Advanced Construction Techniques
Shear Stress vs. Deformation Angle

Nuclear Power Plant
 Fabrication cost is higher for the SC
method
 More susceptible to loss of strength or
deformation when exposed to fire
Drawbacks:

Nuclear Power Plant
Concrete Composition
Technologies
These advancements are due to the use of
admixtures to conventional concrete that
modify its characteristics. such as
increases the comprehensive strength of
the concrete, low permeability, limited
shrinkage, increased corrosion resistance,
reduce the curing time required by
reducing the required thickness of
concrete members as well as the reducing
the number of special construction steps
involved in curing

Nuclear Power Plant
Self-compacting concrete (SCC) is a special
type of concrete mixture that has a high
resistance to segregation. It can be cast
without compaction or vibration. SCC, also
known as self-placing concrete, is
obtained by the addition of a water
reducing agent to a conventional concrete
mix. The water cement ratio remains the
same in the mixture. SCC is a "flowable"
concrete with high compressive strength
Self-compacting concrete (SCC)
Concrete Composition Technologies

Nuclear Power Plant
 SCC provides improvements in strength,
density, durability, volume stability, bond,
and abrasion resistance
 SCC is especially useful in confined zones
where vibrating compaction is difficult
 Reduction in labor costs
Advantages

Nuclear Power Plant
Disadvantages
 The reduction in schedule is limited as
time required to erect and remove
formwork is more
 Higher material costs

Nuclear Power Plant
High performance concrete
(HPC)
 High performance concrete (HPC) is made
with a combination of several different
admixtures (e.g., superplasticizer, flyash,
silica fume, etc.).
 When properly mixed, transported,
placed, consolidated, and cured, it
provides higher performance (e.g., high
compressive strength, high density, and
low permeability) than traditional
concrete.
 In addition, compressive strength for HPC
is typically between 101 MPa and 131 MPa

Nuclear Power Plant
 Early stripping of formwork
 The greater stiffness and higher axial
strength
 High economic efficiency, high utility, and
long-term engineering economy
High performance concrete
(HPC)

Nuclear Power Plant
Reactive powder concrete (RPC)
Reactive powder concrete (RPC) provides
the capability for even higher compressive
strengths than can be achieved with HPC.
Concrete compressive strength can be
increased as high as 200 MPa. RPC is
produced by including individual metallic
fibers in a dense cement matrix. This
reinforcement also increases the ductility
of RPC in comparison to traditional
concrete.

Nuclear Power Plant
 Reduction of structural steel allows for
greater flexibility in designing the shape
and form of structural members
 Superior ductility and energy absorption
provides structural reliability under
earthquakes
 Reduction of structural steel allows
numerous structural member shape and
form freedom
 Superior corrosion resistance
Reactive powder concrete (RPC)

Nuclear Power Plant
Fiber-Reinforced Polymer Rebar
Structures
 composite materials made of fibers
embedded in a polymeric resin, known as
fiber-reinforced polymers (FRP), have
become a corrosion resistant alternative to
steel for reinforced concrete structures.
 Carbon fiber reinforced polymer (CFRP)
and glass fiber reinforced polymer (GFRP)
are two commercially available alternatives

Nuclear Power Plant
 tensile strength nearly 3 times that of
steel rebar and built-in corrosion
resistance
 higher strength/weight ratio
 Long service life due to non-corrosive FRP
material
Fiber-Reinforced Polymer Rebar Structures
Advantages:

Nuclear Power Plant
 Fire-resistance – FRP has a reported susceptibility
to deformation or loss of strength when exposed
to fire
 Seismic adequacy – Seismic performance of FRP
reinforced concrete construction needs to be
demonstrated to gain regulatory approval
 Glass fiber reinforced polymer (GFRP) is less
ductile than steel rebar and may not be able to
with stand extreme loading conditions, such as
those found during severe earthquakes and
Design Basis Accidents
 FRP reinforced concrete has not been used in past
nuclear plant construction and the effects of
radiological degradation are not known
Disadvantages:
Fiber-Reinforced Polymer Rebar Structures

Nuclear Power Plant
High Deposition Rate Welding
The welding processes used in nuclear
power plant construction include:
 Structural welds used to connect
structural members
 Pressure welds used to join pressurized
components
 Weld cladding (i.e., deposition of weld
metal on the surface of another metal to
improve the characteristics of the
component)

Nuclear Power Plant
There are four common standard welding
methods used in large-scale construction
projects:
 gas metal arc welding (GMAW),
 gas tungsten arc welding (GTAW),
 submerged arc welding (SAW), and
 weld cladding.

Nuclear Power Plant
GMAW welding, which includes metal inert
gas (MIG) and metal active gas (MAG)
welding, involves an arc created between
a consumable electrode and the base
metal. Shielding of the arc from the
atmosphere is provided by a gas emitted
from a nozzle surrounding the electrode
Gas Metal Arc Welding:

Nuclear Power Plant
SOLIDIFIED
WELD METAL
BASE METAL
MOLTEN
WELD METAL
SHIELDING GAS
DIRECTION
OF TRAVEL
NOZZLE
ARC

Nuclear Power Plant
Advanced GMAW techniques, which include
the Rapid Arc and Ultramag processes,
 have achieved deposition rates of 15-17
kg/hr in certain applications.
 Deposition rates as high as 30 kg/hr can
be achieved under special circumstances.
 Typical weld deposition rates are in a
range of 1.8-9 kg/hr.
Advantages:

Nuclear Power Plant
 A disadvantage of the gas metal arc
welding process is that
 strict process controls,
 extensive work piece preparation and
cleaning,
 necessary to ensure quality at higher
deposition rates.
Disadvantages:

Nuclear Power Plant
 tungsten arc welding (GTAW), also
referred to as tungsten inert gas (TIG)
welding,.
 This process involves an arc created
between a non-consumable tungsten
electrode and the base metal.
 Shielding of the arc from the atmosphere
is provided by an inert gas emitted from a
nozzle surrounding the electrode.
Gas Tungsten Arc Welding:

Nuclear Power Plant
SOLIDIFIED
WELD METAL
BASE METAL
MOLTEN
WELD METAL
SHIELDING GAS
DIRECTION
OF TRAVEL
WELDING
TORCH
TUNGSTON
ELECTRODE
ARC
FILLER ROD

Nuclear Power Plant
•An automated version of GTAW,
known as orbital welding, is now
an accepted practice in nuclear
applications
•Orbital welding offers significant
improvements over manual
methods for butt welds on piping

Nuclear Power Plant
 orbital GTAW welding process is an automated
welding process. This makes controlling process
variables easier
 facilitates achieving a consistent and high level of
quality.
 The relatively small size of the orbital welder
allows it to be used in locations were personnel
access is difficult or impossible
 Productivity rates are improved over manual
methods because setup is easier and less rework
is required.
 The deposit rate of the orbital process is
approximately 0.7 kg/hr.
 The relative ease of the welding technique
eliminates the need for the skilled welders
required
Advantages:

Nuclear Power Plant
Some problems associated with manual
GTAW are
 difficulty in controlling process variables to
achieve desired quality and
 difficulty in accessing weld locations.
 Both of these problems tend to slow the
construction process and increase cost.
Disadvantages:

Nuclear Power Plant
SAW, involves a consumable electrode that
provides filler metal and shielding. The arc
between the consumable electrode and
the base metal is shielded by the gas
generated by the melting and redeposition
of the flux coating the electrode. The flux
floats to the outside of the deposited weld
metal covering it and providing additional
protection.
Submerged Arc Welding(SAW):

Nuclear Power Plant

Nuclear Power Plant
 In 1996, deposition rates as high as 15
kg/hr were reported for standard single
wire (i.e., single consumable electrode)
subarc welding )
 For a multiple wire process, deposition
rates as high as 45 kg/hr
 vertical applications has achieved a
disposition rate of approximately 2 kg/hr
Advantages:

Nuclear Power Plant
A disadvantage of the SAW process is the
additional cost due to the large amount of
flux cleanup required.
Disadvantage:

Nuclear Power Plant
Weld Cladding:
 Weld cladding involves deposition of weld
metal over the surface of another metal.
 Strip clad welding is a process that
provides high quality weld cladding with
weld deposition rates at least three times
faster than those achieved by current
technology

Nuclear Power Plant
In the process illustrated
in Figure, the weld pool,
flux, and slag are
supported by a ceramic
"hot top." A water-cooled
copper shoe supports and
cools the weld metal as it
solidifies into a solid strip.
The electrode (filler
material) is fed as a strip
(also referred to as a
ribbon) instead of as wire
form.
Weld Cladding

Nuclear Power Plant
 deposition rates for Strip Clad Welding
exceed those of GTAW and SAW.
 This weld deposition rate is approximately
thirteen times that achieved with GTAW
and three times that achieved with SAW.
 superior mechanical and metallurgical
properties for cladding applied by Strip
Clad Welding.
 Exceptional tensile and toughness
Weld Cladding
Advantage:

Nuclear Power Plant
Robotic Welding

Nuclear Power Plant
Robotic Welding
 A typical system consists of a weld head,
robot, user interface, and power supply.
 Automated welding processes can be
divided into two categories: fixed and
flexible
 Fixed automated welding involves
expensive equipment for holding and
positioning weldments.
 Flexible automated welding involves
relatively inexpensive and simple
equipment for holding and positioning
weldments

Nuclear Power Plant
 Increased productivity for large series
production
 Improved productivity for small series production
over early robotic welding systems
 Suitable for shop applications that are typical of
modular construction techniques
 Suitable for complex or simple weld paths
 High level of control over welding process
parameters
 Compatible with automated quality control
processes
Robotic Welding
Advantages:

Nuclear Power Plant
 Field welds are commonly difficult to
access with a robotic welding
 Set up activities are required to use a
robot in a new welding procedure. The
setup includes stooling arrangement and
software programming.
Disadvantages:
Robotic Welding

Nuclear Power Plant
3D Modeling
 3D modeling software allows for greater
visualization of a project.
 This type of modeling has replaced much
of the physical 3D modeling used to
support the construction of domestic
nuclear generating facilities.
 Benefits of 3D design occur in all stages of
the completion of a plant: conceptual
design phase, engineering and detail
design phase, construction phase, and
operations and maintenance phase

Nuclear Power Plant
 A large cost savings resulting from using 3D design
software is the reduction in rework labor and
materials.
 Due to better visualization of the project and
completion of interference checks prior to
construction.
 minimizing the possible errors made in reading
traditional isometric and orthographic views.
 3D design also helps streamline the hazard and
operability review (HAZOP) process.
 The 3D models help check and fix interference
between different design areas, such as piping,
electricity, and Heating, Ventilation and Air
Conditioning (HVAC).
 The 3D software incorporates specifications and code
requirements in a database which helps to avoid
expensive mistakes by recognizing errors and designs
not meeting specifications.
3D Modeling
Advantages:

Nuclear Power Plant
3D Modeling
3D Model of Paper Coating Line Advanced Construction Techniques

Nuclear Power Plant
3D Modeling
3D Model of Offshore Platform

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Positioning Applications in
Construction (GPS and Laser
Scanning)
 GPS was created by the U.S. Department
of Defense (DoD) in 1973 and declared
fully operational in 1994.
 Global Positioning System (GPS) is a
worldwide radio-navigation system
formed from a constellation of thirty-two
satellites orbiting the earth.
 Based on the measurement of the time it
takes for radio signals to travel from the
satellites to a ground receiver, the receiver
calculates its own location in terms of
longitude, latitude, and altitude.

Nuclear Power Plant
Positioning Applications in Construction
Global Positioning System Pictorial Representation

Nuclear Power Plant
GPS equipment used on a construction site
includes:
 GPS receivers – On a new construction site, one
receiver is set up on a permanent base mounting
with an antenna and serves as the reference
station. Other receivers are roving receivers.
Signals of the roving receiver are corrected by
errors calculated at the stationary reference
receiver whose position is accurately surveyed
and well known Stationary reference receivers
have been established across the country by
government agencies and are available for public
use.
 Computer – The computer takes the GPS data and
translates it into a site plan
 Radios – Information is relayed between
receivers and other equipment on the site by a
high speed radio network

Nuclear Power Plant
Application of GPS technology to
Field construction:
 Surveying
 Earthmoving
 Material and Equipment Tracking
 Measurement of Structural
Deformation and Alignment
 Indoor Measurement Tools

Nuclear Power Plant
GPS Information Tracking During Site Land
Development

Nuclear Power Plant
GPS has additional potential benefits to new
nuclear plant construction. These potential
benefits include:
 Accurate and time efficient placement of
equipment and large structures
 Automation of drawing revisions
 Material and equipment tracking off-site
and on-site
 Robotic inspection of critical components
 As-built measurement of piping and
equipment

Nuclear Power Plant
Open-Top Installation
 In previous domestic nuclear power plant
construction, the as-built construction schedules
from first concrete (FC) to fuel load (FL) were
long and few tasks could be completed in parallel.
 In the open-top installation construction
sequence, part of the Reactor Building is built,
followed by placing the Reactor, Steam
Generators, and other large pieces of equipment
in place in the building using large cranes.
 Once the equipment has been placed inside, the
construction of the Reactor Building can be
finished while other site workers install piping
and electrical systems.

Nuclear Power Plant
Open Top Installation

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It is estimated that Open-Top Installation
in combination with modularization
techniques can shorten the construction
schedule from 10 to 15 years to as few as
4 to 5 years from first concrete to fuel
load. Even limiting the use of this
technique to the installation of major
components can save massive amounts of
time.
Open-Top Installation

Nuclear Power Plant
Pipe Bends vs. Welded Elbows
 Domestic nuclear power plants were constructed
using welded pipe fittings, such as elbows, in
piping systems throughout the plant.
 Extensive construction materials and labor are
required at the construction site to support this
type of piping system construction. This method
contributes to the long construction period
typical of large-scale field constructed projects.
 Pipe bending is a simple alternative construction
technique that can speed up piping system
construction and reduce the number of workers
required.

Nuclear Power Plant
Comparison of Piping System Construction Pipe Bends vs. Welded Elbows

Nuclear Power Plant
The most common pipe bending
techniques are :
 cold bending,
 induction bending, and
 hot slab bending.

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Types of Cold Bending

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Schematic of a Heat Induction Bending Machine

Nuclear Power Plant
 The use of pipe bends eliminates a large
amount of the field welding required.
 This will decrease the time required to
perform field welding and shorten the
construction schedule.
 The number of welders required on-site
will also be reduced.
 It also reduces shoring and scaffolding
required onsite.
 It reduces the radiation exposure to
personnel who perform the inspections.
Advantages:

Nuclear Power Plant
Precision Blasting/Rock
Removal
Precision blasting for excavation involves
drilling a series of shafts in an engineered
pattern in the area to be removed. The
shafts are filled with explosives and a
detonation cord is run to a central location
at the site. The charges are set off in an
order designed to maximize the excavation
with minimal amounts of debris and sound
damage to the immediate area.

Nuclear Power Plant
 Reduction in schedule
 Precision blasting costs are approximately
1/3 the costs of traditional mechanical
excavation methods, such as drilling and
digging.
 Part of the cost reduction is due to the
ability to remove or loosen a significant
portion of the rock for the desired
foundation in a short time.
 Blasting also reduces the personnel and
equipment (and associated maintenance
costs) required on-site during the
excavation process.
Advantages:
Precision Blasting/ Rock Removal

Nuclear Power Plant
 Improperly controlled blasting has the
potential to initiate problems if performed
at a site with a currently operating unit.
 Seismic activity can result,
 damaging the equipment at the other unit
or damaging footings or other concrete
work that is being performed nearby.
 Improperly performed blasting has the
capability to change the stability of the
local geology, potentially leading to
cracking or ground openings
Disadvantages:
Precision Blasting/ Rock Removal

Nuclear Power Plant
Cable Pulling, Termination and
Splices
 Cable pulling broadly refers to the
installation of cables in cable trays or
conduits
 Cable splicing is the joining of the two free
ends of two cables together.
 Cable termination describes the treatment
of a cable end which is connected to the
electrical load or power source.

Nuclear Power Plant
The advancements that provide a reduced
coefficient of friction (COF) are:
 High performance lubricants
 Cable tray rollers
 Cable tray sheaves
Other advancements in cable pulling
include:
 Automatic lubricant application
 Assisted pulling devices
Cable Pulling
Cable Pulling, Termination and Splices

Nuclear Power Plant
The commonly used methods of splicing are
as follows:
 Cold Shrink
 Heat Shrink
 Premolded
Cable Splicing

Nuclear Power Plant
 The function of a typical termination is to
provide a cable end seal, electrical stress
control, and external insulation covering.
 The cable end seal protects the cable
from moisture.
 The commonly used methods of cold
shrink, heat shrink, and premolded
preparation described above for cable
splicing also apply to cable termination.
Cable Termination

Nuclear Power Plant
Advanced Information
Management and Control
 Information management and control
consists of acquisition, storage, retrieval,
and manipulation of the plant information.
 CANDU and FIATECH have developed
several advanced information technologies

Nuclear Power Plant
It is recent nuclear power plant construction
project in China, known as the Quinshan
CANDU project. It includes:
 The Asset Information System and TRAK
databases,
 The CANDU Material Management System,
and
 The Integrated Electrical and Control
Database.
Advanced Information Management and Control
CANDU:

Nuclear Power Plant
 FIATECH, which stands for Fully Integrated and
Automated TECHnology, is a partnership of the
National Institute of Standards and Technology,
industry (including major construction
companies, software vendors, oil companies, and
utilities), and other government organizations.
 FIATECH’s mission is to direct industry and
government appropriations for research and
development of new construction technologies.
FIATECH is also addressing new materials, new
construction methods, and workforce issues
FIATECH :

Nuclear Power Plant
According to FIATECH, the benefits of
advanced information flow include:
 Up to 8% reduction in costs for facility
creation and renovation
 Up to 14% reduction in project schedules
 In addition, FIATECH estimates that
improving the interoperability of software
Used for capital projects would result in
savings of $1 billion per year for industry.
Benefits:

Nuclear Power Plant
The CANDU project benefited from the use of
advanced information management technology in
the following ways:
 The material management system allowed for
accurate identification of materials, smoothing
the process for materials that required quality
assurance and traceability. This is an important
improvement for a nuclear power plant
 The electronic data management system ensured
that the project team did not have to recreate
information for purchase orders
 The electronic data management system will be
the basis for inventory, operation, and
maintenance once the plant is on-line
Benefits:

Nuclear Power Plant
Prefabrication, Preassembly, and
Modularization
 Prefabrication is a manufacturing process,
generally performed at a specialized
facility, where materials are joined to form
a component part of a final installation.
 Preassembly is a process by which various
materials, prefabricated components
and/or equipment are joined together at a
remote location for subsequent
installation as a unit.
 A module results from a series of remote
assembly operations, possibly involving
prefabrication and preassembly.

Nuclear Power Plant
 Reduces construction cost and schedule.
 Parallel paths for work lead to schedule
compression.
 More effort is shifted into planning,
design, and procurement.
 The manpower required at the
construction site is leveled throughout the
project.
 Prefabrication, preassembly, and
modularization should result in better
quality control since more work is
performed in the shop than in the field.
Prefabrication, Preassembly, and Modularization
Benefits:

Nuclear Power Plant
Construction Schedule
Improvement Analysis
 The potential reduction in construction
time is quantified for the technologies
recommended for further industry-
sponsored research and development. The
following technologies were evaluated:
 Cable Laying, Splicing, and Termination
 Modularization
 steel-plate reinforced concrete structures.

Nuclear Power Plant Advanced Construction Techniques
Construction Schedule Improvement Analysis
Construction Method Estimated Schedule
Reduction
(Months)
Steel-Plate Reinforced Concrete Structures 2.3
Cable Splicing 1.3
Modularization 5

Nuclear Power Plant
Components of Nuclear Power Plant
Discharge Channel,
Natural source of water supply,
Pump house,
Machine room,
Nitrogen-Oxygen station,
Main Building (i.e. Reactor building),
Connecting unit, pipeline,
Special water treatment Plant,
Waste storage,
Burial grounds,
Ventilation chimney,
Fire brigade,
Garage,
Store house,
Auxiliary boiler room,
Chemical water treatment plant,
Sanitary premises,
Administrative building,
Auxiliary workshop,
Oil storage,

Nuclear Power Plant
Reactor Building Section through N-S Direction

Nuclear Power Plant
Reactor Building Section through E-W Direction

Nuclear Power Plant
Case Study
 Kaiga site is located about 13 km upstream of Kadra
hydro-electric power project, on the left bank of Kali
river, in Karwar Taluka of Uttara Kannada District of
Karnataka State.
 The site has the potential of producing 2000 MWe.
 The Government of India sanctioned Kaiga-1&2 in 1987
for installing 2 x 220 MWe Pressurised Heavy Water
Reactors (PHWRs) at Kaiga site in the first phase.
 These units were commissioned in 1999 and 2000 resp.
 Government of India sanctioned two more units of 220
MWe PHWRs in the year 2001, with a stipulation of
commercial operation by October 2008 and October
2009 resp. at a projected cost of Rs. 42130 million.
Construction of Kaiga Nuclear Power Plant

Nuclear Power Plant

Nuclear Power Plant
 These reactor building have been designed with
double containment structures
 Inner containment structure is a 42-m diameter
Prestressed concrete cylindrical vessel with a
torospherical dome at the top.
 Outer containment structure is of RC Structure
 a prestressed concrete dome with four opening of
4.1m diameter (for replacement of steam
generators)
 High performance concrete (HPC) of grade M-60
had been used for this dome.
Salient features:
Case Study

Nuclear Power Plant
 The dome consist of a ring beam 4.1m deep and
thickness varying from 1.3 m to 2.15m, and a shell of
470 mm thickness at the crown and 1,137 mm springing
level .
 550 t of structural steel was used to support the entire
formwork.
 Total surface area of formwork was over 2,600 m3.
 Nearly 360 t reinforcement and 200 t of high tensile wire
were used
 The total volumes of concrete was 2000 m3 concerting
commenced on January 6,1998 in eight pours which
included the pumping of HPC to a height of 50m by the
latest concrete pumps and placers.
The Dome
Case Study

Nuclear Power Plant
610
1
1
3
7
1603
4
7
0
1
2
2
0
470
STEAM GENERATOR OPENINGS
C LINE OF
I.C. DOME
L
RING BEAM
C LINE OF
I.C. DOME
L
EL 36035
EL 31700
Case Study
Cross section of ring beam and dome

Nuclear Power Plant
 High performance concrete of grade M-60 was
design to meet following specified parameters.
 Characteristic compressive strength = 60 N/mm2
 Characteristic split tensile strength = 3.87 N /mm2
 Crushed granite stone of 20 mm maximum size was
used as coarse aggregate and river sand as fine
aggregate.
 43- grade ordinary Portland cement (OPC)
 7.5 percent microsilica by weight of cement
 use of high range superplastisizers and retarders
Development of concrete mix design
Case Study

Nuclear Power Plant
Following were the mix proportions.
Cement : 475kg
Microsilica : 35.6kg
Water / ice : 163kg
Coarse aggregate : 1,092kg
Fine aggregate : 659kg
Admixture
Superplastisizer : 8.0litter @2 percent by weight of cement
Retarder : 0.4litre @0.1percent by weight of cement
w / c : 0.343
w / b : 0.32
Development of concrete mix design
Case Study

Nuclear Power Plant
 Dome supporting structure consisted of 32nos. of
built up plate girders as radial members and
22nos. of trusses as circumferential members.
 The complete structural was Supported on 32
brackets fixed to the containment wall and on ten
derricks resting on the Internal structures.
 Dome soffit formwork consists of panels of 12mm
thick plywood resting on wooden battens.
 All the shutter panels were fabricated to the
curved profile of dome, properly numbered and
placed on runners supported by screw jacks
 Profile of dome soffit was maintained to an
accuracy of +3mm.
 Standard Doka system of formwork was used.
Formwork
Case Study

Nuclear Power Plant
 High yield strength deformed (HYSD) bars of
grade Fe 415
 To reduce the congestion in the structure, lapping
of reinforcement was avoided.
 All the bars were cut, bent and tagged as per the
bars bending schedule, which was meticulously
prepared
 Bars of unequal diameters were mechanically
spliced
 Multipurpose chairs were used for supporting the
prestressing cable and top mat of reinforcement .
 Radial reinforcement was provided in the shape
of C links connecting tops and bottom mats.
 Specially designed mechanical fasteners were
used at the transition zone as radial
reinforcement.
 Cover blocked of M 60 grade concrete
Reinforcement
Case Study

Nuclear Power Plant
 19 K 13 CCL, UK prestressing system was used
 19 strands of 7 ply. 12.7 mm diameter high
tensile wires of low relaxation steel were used to
form a cable 80mm diameter corrugated sheaths
were manufactured at site using lead coated Mild
steel strips.
 19 nos. of stand were bunched to form one cable,
tried together at regular interval and properly
identified.
 To erect these cables on the dome, specially
designed decoiler was used.
 cable were aligned and supported using
templates at regular interval to an accuracy of
+5mm.
Prestressing System
Case Study

Nuclear Power Plant
 Pan Type of concrete mixer
 two semi automatic batching plants of 20m3 / hour
capacity each with plan type mixer were used.
 Cement was loaded in the 100t capacity silo and conveyed
to mixer through screw conveyor .
 aggregates were stored in compartment star bins.
 Aggregates were screened through specially designed
flakiness screen to reduce the flakiness and elongation
index below 15 percent.
 River sand was washed at site
 To reduce the temperature of concrete, part of the mixing
water was replaced with Ice flakes of 1.5mm thickness.
 Superplasticizers and retarders were premixed in the
required proportion
 Concrete produced was very cohesive uniform and of self-
leveling consistency of 200 mm slump. To achieve concrete
placement temperature below 230C production
temperature was maintained between 120C to 150C.
Concrete Production
Case Study

Nuclear Power Plant
 Concrete was transported from batching plant to
site which was nearly 1 km away by transit mixer
of 4 m3 and 6 m3 capacities.
 Total 7 transit mixer used
 Drums of transit mixer were insulated to reduce
the increase in concrete temperature.
 For proper control and supply of concrete
management at site, each transit mixer carried a
dispatch slip containing details of batching plant,
concrete quantity in transit mixer, cumulative
quantity and time of dispatch.
Concrete Transportation
Case Study

Nuclear Power Plant
Concrete was placed into the structures at a height
of 50 meter using
the following equipment.
 Concrete pump, schwing 3000 R -1 no
 Concrete pump, schwing 550 BP -2 nos. (One
standby)
 Concrete pump, schwing 350BP -1 no (standby)
 Concrete placing boom mounted on lattice tower
DVMK 42 (42M reach) 1 no
 Concrete placer KVM 28 / 24 (24 m reach)
mounted on one of the steam
 generator Opening of dome – 1 no.
 Direct pipe line -2 nos. (Standby)
 Tower crane and concrete bucket -1 no.
(Standby)
Concrete Pumping
Case Study

Nuclear Power Plant
stand-by pipe line 1
Boom placer
(KVM 24 / 28 )
stand-by pipe line 2
Tower crane
(G3-33-B)
Heavy duty tower
Stair tower
Boom placer
DVMK 42
Admixture
re-dosing unit
Ramp
pump 1
pump 2
pump 3
pump 4
Case Study

Nuclear Power Plant
Concrete Placement
1603
995
1300
600
C of I.C.wall
L
EL 31700
EL 32700
EL 35100
EL 36035
Pour-3
(200 m3)
Pour-3
(576 m3)
Pour-3
(192 m3)
•Ring beam was
concreted in 3 pour
with 2 horizontal
construction joints
•Total quantity of
concrete in ring beam
was 970 m3
•Concreting was
planned at the rate of
20 m3/hr
• To avoid any cold
joints and loss of
moisture from
exposed surface,
pour sequence was
designed with a
returned period of
one hour

Nuclear Power Plant
 Dome concreting was completed in 5 pours
using following sequence.
 Pour 5A-150 m3
 Pour 5B-150 m3
 Pour 4-45 m3
 Pour 6A & 6B -200 m3
 Pour 7-410 m3
 Inter pour gap of one week was maintained
between all the pours.
 Concreting of pour 5A, 5B and 4 was done using one pump and
placers at the rate of 10 m3/hr and pour 6 &7 using two
pumps and placers at the rate of 20 m3/hr.
 At all the areas where the slope was more than 150 top
shutters were also used
 Top formwork consisted of steel trusses and 25 mm thick, 200
mm wide timber planks as shutter panels
 To facilitate inspection during concreting, observation windows
and cut-outs were made in critical areas.
Dome

Nuclear Power Plant
Pour-7
Pour-5B
Pour-4
Pour-5A
Pour-7
Pour-7
Pour-7
Pour-6A
Pour-6B
Pour plan of dome concreting

Nuclear Power Plant
 Concrete was compacted using needle
vibrators.
 Normally 60 mm needle was used but at
certain very congested locations, 40 mm
needle was also used.
 Surface vibrators were also used to
compact the concrete just below the top
shutter panels.
Compaction

Nuclear Power Plant
 For preparation of construction joints in the ring
beam, surface retarder was sprayed on the
concrete surface within half an hour of its
reaching the top level of the pour.
 surface was then green cut using the high
pressure air water jet after 8 to 12 hour of
concreting to remove top 5 to 7 mm layer of unset
mortar
 On stopper shutter between adjacent pour of
dome surface, retarder was applied four hours
before starting the concreting.
 These shutters were removed progressively 8
hour after the concreting and surface was wire
brushed.
Preparation of construction joints

Nuclear Power Plant
 To prevent the lost of moisture curing compound
was sprayed uniformly using back pack spray
gun.
 curing compound was applied after the final
finishing of the concrete, and as soon as the
water sheen disappeared from the concrete
surface.
 After drying of curing compound plastic sheet was
also spread over the concrete surface.
 Wet curing continued for a period of 10 days
 concrete pours in the evening, so that major part
of the concreting could be done in the cool hours.
Curing

Nuclear Power Plant
 A stringent quality assurance (QA) was adopted
 Detailed QA manual was prepared and all the materials
were tested as per the QA plan.
 stage inspection of formwork, reinforcement and
prestressing cable alignment was carried out using specially
designed templates to achieve strict tolerances.
 Batching plants were calibrated before starting of every
pour to an accuracy of +1 %
 Moisture content of fine aggregates was determined at a
regular interval
 for every 50m3 of concrete, samples were taken for
determination of various properties of fresh and hardened
concrete.
 All these activities were independently carried out by a term
of specialised quality assurance personnel.
 Duties of each engineer clearly identified.
 proper documentation of records was maintained by filling
specified format for each activity.
 All people like masons and operation handling vibrators,
construction chemical were given training in their
respective areas.
Quality assurance and quality control during construction

Nuclear Power Plant
 The successful construction of plant is a result of
good team work.
 Structure was designed by STUP consultants,
Mumbai and proof checked by NPC design office
as well as by external consultants who were
expert in the field of nuclear reactor design.
 The design required HPC of grade M- 60 which
was developed by NPC at kaiga site. Larsen &
Toubro ECC group who were the contractor
carried out the construction efficiently with in a
tight schedule, employing high level of
mechanized construction.
Conclusion

Nuclear Power Plant.ppt

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