- Since 1976, working for development of strong motion instrumentation network in India. Formulated, negotiated and received several strong motion projects from Department of Science and Technology (DST), World Bank, Tehri Hydro Development Corporation and other river valley projects. These efforts have significantly contributed in making Department of Earthquake Engineering, IIT Roorkee as the nodal agency of strong motion instrumentation in India and abroad.
- Almost all major earthquakes that have struck our country after early 80’s have been recorded by this instrumentation. These records have created an extremely important data base which has been widely used by engineers and scientists for research and application in the field of earthquake engineering and seismology.
- Above efforts have resulted into award to IIT Roorkee, a most prestigious mission mode project of Department of Science and Technology (now with Ministry of Earth Sciences). In this project named as “National Strong Motion Instrumentation Network”, we developed a network of 300 digital strong motion accelerographs covering area of seismic zone IV, V and some densely populated cities of zone III. About 240 of these instruments are connected through NICNET / SWAN of NIC. This state of the art instrumentation was one of the largest network of strong motion instruments in world with almost real time capability covering a window of about 2000 km x 300 km. A website named as www.pesmos.com has been developed and all the recorded time histories are uploaded in this website for registered users. As of now, about 600 time histories from 200 earthquakes have been uploaded in this web site.
- Formulated and developed use of synchronous noise (having absolute flat power spectrum) for evaluation of different numerical schemes used for processing of data as well as analysis of systems.
- Developed and disseminated widely, several digital signal processing software with graphic interface. List of software and a brief description of each is given in this webpage. Latest being, software for development of spectrum compatible time history with fling. These software are being commonly used by students and researchers in India and abroad.
- Band limited interpolation scheme, which is quite common in image processing, was introduced for use for earthquake engineering data. It has been shown that prevalent interpolation schemes using first or higher order interpolation substantially distorts the digital data and can adversely affect the engineering results.
- New scheme for processing of accelerogram in frequency domain was developed. Its advantages over prevalent time domain processing schemes were highlighted.
- Performed in-depth analysis on various aspects of ground motion of all recorded earthquakes. For Bhuj Earthquake of 2001, records of SRR were used to find attenuation relationship of the region, which has then been compared with Eastern North America ground motion attenuation relation. Under an Indo Norwegian project, attenuation characteristics of spectral acceleration using recorded acceleration time histories was done.
- For the first time in India, an extensively instrumented multistoried building at Ahmedabad provided records of its response of its different floors during Bhuj earthquake of 2001. Using structural drawings of the building, it was analyzed for recorded ground motion and analytical as well as recorded response were then compared and studied in detail. Model of the structure was fine tuned and effects of soil structure interaction is being studied in detail.
- Carried out hazard analysis of NCR Delhi using recorded data of earthquake. PGA and spectral acceleration scenario were estimated for M 7, 7.5 and 8 earthquakes from Himalayas as well as M 5 earthquake near Delhi.
- Research is being carried out in regard to various aspects of earthquake early warning system. We have done substantial work on attributes for earthquake early warning system and have found best combinations of five attributes and has shown that this combination give most reliable results using worldwide strong ground motion data comprising of about 2000 time histories recorded at hypocentral distance of less than 60 km.
- Developed earthquake early warning system for Northern India. In the first phase of this project, 86 accelerometers were installed in Garhwal region and in the second phase additional about 80 sensors are installed in Kumaun region of Uttarakhand. All these sensors are streaming real time acceleration time history (24 hours x 7 days). Software is being developed in Earthworm (an open source real time seismic signal processing platform) for real time processing of streamed acceleration time history for issue of warning. About 100 sirens have been installed in various government offices of Uttarakhand. We anticipate that we may be able to provide about 70 seconds of warning to Delhi before damaging S waves strikes Delhi from earthquakes originating from Himalayas.
- Developed, maintained, operated, upgraded and extensively used the prestigious shake table facility of the Department of Earthquake Engineering. Large number of seismic tests of power plant equipment of reputed private and public sector companies were conducted on this facility.
- Worked as Organizing Secretary of 12th Symposium on Earthquake Engineering, which was conducted with great success on December 16-18, 2002. About 250 delegates from 15 different countries participated in the symposium. Edited two volumes of the conference proceedings comprising of 169 technical papers. For the first time, conference proceedings were made available in a CD.
- In the year 1991, developed a microprocessor based digital accelerograph under a research scheme of DST. This accelerograph has a resolution of 12 bits. Technology transfer document were prepared and technology was transferred to a Delhi based private enterprise.
