Nuclear Reactor Technology has found potential in this era where innovation and development are keys to build a brighter future. The massive abundance of energy released through the process of fission, as well as fusion, are being harnessed and used at constantly increasing efficiencies. The first artificial nuclear reactor, called the Chicago Pile-1, was constructed at the University of Chicago, by a team led by Enrico Fermi, in late 1942. This was the seed that led to the growth and understanding of nuclear energy technology all over the world, utilizing newer and better ways to increase the efficiency and safety of the Nuclear Reactors as a whole.
The total installed capacity for electricity generation in the country has increased from 16,271 MW as on 31.03.1971 to 206,526 MW as on 31.03.2011. (Energy Statistics, 2012)
Nuclear power is the fourth-largest source of electricity in India. As of 2010, India has 20 nuclear reactors in operation, in six nuclear power plants, generating 4,780 MW while seven other reactors are under construction and are expected to generate an additional 5,300 MW.
As in previous years, during the year 2010–11, demand for electricity in India far outstripped availability, both in terms of base load energy and peak availability. Base load requirement was 861,591 (MU) against availability of 788,355 MU, an 8.5% deficit. During peak loads, the demand was for 122 GW against availability of 110 GW, a 9.8% shortfall (Central Electricity Authority, Govt. of India Ministry of Power, 2011).
Power Plants Located Across India
• Narora Atomic Power Station
• Rajasthan Atomic Power Station
• Tarapur Atomic Power Station
• Kakrapar Atomic Power Station
• Kudankulam Nuclear Power Plant
• Madras Atomic Power Station (Kalpakkam)
• Kaiga Nuclear Power Plant
India, like rest of the world, faces a high demand for energy that needs to be satisfied by the end of this decade, and Nuclear Technology is our best option in achieving such a goal. There have been incidences of public outcry pertaining to the safety of the Nuclear Containment Structure. The mass protests against the French-backed 9900 MW Jaitapur Nuclear Power Project in Maharashtra and the 2000 MW Koodankulam Nuclear Power Plant in Tamil Nadu, and the state government of West Bengal state refusing permission to a proposed 6000 MW facility near the town of Haripur that intended to host six Russian reactors are some examples of such problems that hinder the development of this energy technology.
The reasons and vacillations regarding its safety have been considered by scientists and engineers, and are found to be manageable, solutions of which, can be resolved through proper analysis and design.
A common misconception about a nuclear power plant’s containment structure is that their massive concrete construction is a protection against the release of radioactive products in the case of a postulated accident. Such a task is achieved by the overall containment system as a collection of the “Engineered Safety Features,” not just by the concrete shell alone. It must be understood that the concrete component is meant as a biological shield against gamma-ray radiation and a protection of the reactor internals against damage from the effects of nature like that of an earthquake and the effects of the outside elements including missiles such as light posts driven by tornado or hurricane 100-miles per hour winds, and even the direct impact by a massive aircraft such as a Boeing-747. The concrete shell in fact is strong at its exterior curvature, and weak at its interior curvature. This is an inherent characteristic of shell structures. Think about how difficult it is to crush an egg by squeezing it in one’s hand, yet it is easy for the weak and helpless chick to peck its way out of the interior of an egg’s shell. The concrete shell is designed to withstand the direct impact of an aircraft on its exterior, but miserably fails a build-up of stress at its interior. An increase of stress by steam release, if unquenched, at its interior will eventually cause it to fail; much like a chain at its weakest link. The weakest links in that case occur at the coolant inlet and outlet pipes and the instrumentation cabling and electrical power penetrations.
Pre-stressed concrete (PSC) structures, the best example of engineering structure that has excellent structural efficiency, are widely used in various engineering works. As PSC structures are economic and have fine shape, increasing number of engineering works are being conducted using PSC structures. Since the 1960s, many have tried to analyze complex structures in a more substantial way using finite element method. It is almost impossible to conduct experiment on every structure because each structure is different in its structural type, materials, and surrounding conditions. Experiment under specific conditions also should risk failures and high costs. In this regard, finite element method can be a good alternative because it enables easy control of various conditions such as shape, load, and boundary. Using the method, it is also possible to check the internal stress of a structure. With the continuous methodological improvement and development of high-performance computers, finite element method is now widely used in analyzing complex structures. It is also now possible to take in various other factors into the analysis so as to attain more realistic data regarding the structures behaviour. The elastic behaviour of concrete comprises of the linear phase, which have been studied and used as a means of design, and a non-linear phase. Structural nonlinearities are encountered on a routine basis. For instance, whenever two pieces of paper are stapled together, the metal staples are permanently bent into a different shape you heavily load a wooden shelf, it will sag more and more as time passes. As weight is added to a car or truck, the contact surfaces between its pneumatic tires and the underlying pavement change in response to the added load. If a plot of the load-deflection curve for each of these examples were to be drawn, it would discovered that they all exhibit the fundamental characteristic of nonlinear structural behaviour - a changing structural stiffness.
The potential of the non-linear phase has not been completely utilized in structures due to its complexity and enormous time consumption. The development of analysis softwares has changed this view and now, it is possible to reap benefits from even the non-linear phase of concrete behaviour. A nonlinear analysis is necessary in this order to study, understand and improve the capability of the structure to resist these loads.
In conclusion, the importance of nuclear technology has been recognized world over and being in possession of such technology it is only natural that we use it for the development of our nation. As civil engineers it is in our interest to find ways to ensure safety and security in that regard through research and application of technology and analytical that are already out there in the world.
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Article By:
Mr.Nishanlulu Mohd Jaleel
Asst. Prof.
Department of Civil Engineering
Sphoorthy Engineering College
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| Sphoorthy Engineering College |
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