Nuclear Power plants in India have been designed for earthquake resistance by the methods of analysis & testing. Many of the electrical & instrumentation equipment have been tested on shake tables available in India. The performance of the civil structures, piping systems, cable trays, ducting and mechanical, electrical, instrumentation & control equipment in industries around Koyna (1967, 6.5M), Bhuj (2001, 7.6M) & Muzaffarabad (2005, 7.6M) which have witnessed the earthquake is also available. Contrary to the common perception that Koyna, Bhuj and Muzaffarabad earthquakes were a complete disaster, the data collected on equipment performance from the industries around the earthquake affected area was that the equipment and piping failure due to inertial load were rather nil and wherever the failures were there, they were due to total collapse of the civil structure on which they were installed or falling of brick wall on to the equipment or piping or failure of equipment due to improper or no anchorage of the equipment or due to seismic anchor movement to rigid piping. Apart from the failures of transformers on wheels, battery banks on wooden stillage, false ceiling, lighting fixtures and brick walls the performance of other equipment was good (tanks, pumps, valves, compressors, DGs, fans and blowers, chillers, HVAC ducts, cranes, switchgears, MCCs, battery chargers and inverters, distribution panels, MG sets, cable trays, instrumentation and control panels, instrumentation devices like relays, temperature and pressure sensors, switches, meters etc) Indian experience on equipment which have witnessed earthquake is from the general industry, although not from the Nuclear Power Plants, viz. thermal & hydro power plants, chemical & fertilizer industry, cement plants, petrochemical plants, electrical substations etc. and is very similar to the experience at Kashiwazaki-Kariwa NPP on soft rock(Vs30 200m/sec) and Shika NPP on hard rock(Vs30 1500m/sec) in Japan. Earthquake experience data from USA, European countries, Russia, Japan etc. as available in the form of Generic Implementation Procedure GIP-DOE, GIP-SQUG, GIP-WER, FEMA, ASME-QME 1-2000, IEEE-628 etc. as collected by various institutes e.g. EPRI, EERI, S & A, LLNL from USA have also been used. The performance of the equipment during the shake table tests or during the earthquake forms the data base of equipment, which can be used by general industry as well as by nuclear industry for their design and forms the part of the experience based data.
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