[en] This volume contain papers on the major criteria for selecting sites for establishing nuclear power plants. This also deals with the operational safety of reactors and future plans for establishing nuclear power plants. Papers relevant to INIS are indexed separately

[en] This paper presents the fragility analysis of reinforced concrete ventilation stack existing at Kalpakkam, India. The median peak ground acceleration capacities are estimated to be 0.208g and 0.307g for serviceability and flexural yield conditions respectively. The corresponding high confidence low probabilities of failure capacities are estimated to be 0.082g and 0.13g. (author)

[en] After an overview of the use of microearthquake survey in decisions related to the siting of nuclear power plants, the main aspects of a microearthquake survey network are discussed. The use of microearthquake surveys in investigation problems related to earthquake is also discussed. The discussions are centered on the practical application of such a survey leading from objectives and limitations over to planning, instrumentation, operation and maintenance, processing of the data and interpretation and reporting of the results. (author)

[en] A Tri-axial shaker system has been established at earthquake engineering and vibration research centre, CPRI, Bangalore to carry out seismic and vibration qualification tests on equipment. Design of suitable reaction mass foundation for the shaker system is critical. Details of different alternate types considered for analysis and evaluation and their relative merits and demerits are brought out. (author)

[en] Since years world had experienced number of earthquakes and in India, zones have been modified according to the severity of earthquake and all this have made designers and engineers to concentrate rigorously to bring down the effect of damage to structures. Since the response of the structures to seismic force mainly depends on the distribution of mass, stiffness and damping characteristics an attempt is being made to compare and study the response by improving these characteristics in a simple building frame with and without infill. This in turn gives an idea of interconnecting the adjacent buildings of nuclear island to reduce the hazard to a minimum. (author)

[en] Non-satisfactory functioning of snubbers as seismic supports for piping system is well established through the past studies. A cost-effective alternative to the use of snubbers in the piping system is non-linear supports as energy dissipating devices. An increase in the damping ratio is known to be very effective for the seismic design of a piping system. It is reported that the energy dissipation in piping supports contributes to increasing the damping ratio of the piping system. With regard to increasing the damping and reducing the seismic response of the piping system, performance of x-shaped steel plate supports is investigated as a damping device in the present study. Two simple models namely 1-dimensional and 3-dimensional piping systems are considered for the study. Wen's smooth hysteretic model is chosen to represent the restoring force in the non-linear supports. Both linear and non-linear time history analysis is performed using Newmark's time integration method. The results show that non-linear supports can be very effective in reducing the seismic forces. (author)

[en] Control rod and its driving mechanism for a Fast Breeder Reactor is to facilitate safe shutdown of the reactor in case of emergency. A theoretical study on the seismic qualification of control and safety rod driving mechanism is carried out. Earthquake excitations under Operational Basis (ORE) and Safe Shutdown condition (SSE) are considered. The time required for the control rod to reach the bottom position in order to shut down the reaction under excited condition is traced out. The maximum displaced positions and extreme stresses in various parts of the system under excitations are evaluated. The system modeled using beam elements. The connections between different parts are modeled through rigid elements. The interaction between various parts are modeled using GAP elements. (author)

[en] Indira Gandhi Centre for Atomic Research (IGCAR) is setting up a 500 MWe Prototype Fast Breeder Reactor (PFBR) at Kalpakkam, Tamilnadu. Nuclear Island Connected Building (NICB) of PFBR is a major safety related structure. This paper provides salient features of the seismic analysis of NICB which includes the analysis strategy adopted, finite element modelling, modal analysis, response spectrum analysis, transient analysis and generation of in-structure response spectra. (author)

[en] Various statistical models have been developed in the past to model the seismicity of a region and to evaluate its seismic hazard. Gutenberg and Richter model based on magnitude frequency relationship in combination with Poisson process assumption is a simple and widely used model to evaluate the seismic hazard. The quadratic magnitude frequency model, doubly truncated exponential model and the extreme value models are some advances in modelling the seismicity. Such models are either based on the type of catalogue data (i.e. its completeness) or on the mechanics of the earthquake occurrence process. In this paper, various statistical models have been briefly discussed and a case study to estimate the seismic hazard for Peninsular India has been presented. The paper provides an insight into the various models available for seismic hazard estimation, and their applicability to the particular region. Based on the study, it has been found that the extreme value model is well suited for modeling the magnitude uncertainty in the region with medium to low seismicity and results in statistical estimation of maximum magnitude earthquake expected in the region corresponding to design life of various structures. Such estimates provide very important information for design and maintenance of various critical facilities like dams and nuclear power plants. It has been concluded that the seismicity and hazard to critical facilities in Peninsular India should be estimated using multiple hypotheses. (author)

[en] The importance of Nuclear power plants and the consequences of a nuclear accident require that the nuclear structures be designed for the most severe environmental conditions. Earthquakes constitutes major design consideration for the system, structures and equipment of a nuclear power plant. The design of structures on ground is based on the ground response spectra. Many important parts of a nuclear power plant facility are attached to the principal parts of the structure and respond in a manner determined by the structural response rather than by the general ground motion to which the structure is supported. Hence the seismic response of equipment is generally based on the response spectrum of the floor on which it is mounted. In this paper such floor response spectra have been generated at different nodes of a chosen model structure of a nuclear power plant. In the present study a detailed nonlinear time history analysis has been carried out on the mathematical model of the chosen Nuclear Power Plant model structure with the spectrum compatible time history. The acceleration response results of the time history analysis has been used in the spectral analysis and the response spectra are generated. Further peak broadening has been done to account for uncertainties in the material properties and soil characteristics. (author)