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Present Research

I am presently involved in the research of Seismic Hazard Assessment. A seismic hazard is the probability that an earthquake will occur in a given geographic area, within a given window of time, and with ground motion intensity exceeding a given threshold. The estimation of the expected ground motion, which can occur at a particular site, is vital to the design of important structures such as dams, bridges and nuclear power plants. The process of evaluating the design parameters of earthquakes ground motion is called seismic hazard assessment. The design parameters are Target Response Spectra (TRS), Design Acceleration Time Histories compatible with the TRS, Peak Ground Acceleration (PGA), Design Response Spectra, Seismic Coefficients etc. There exists two approaches of seismic hazard assessment - (i) Deterministic Seismic Hazard Assessment (DSHA) (ii) Probabilistic Seismic Hazard Assessment (PSHA)

The process of DSHA involves the initial assessment of the maximum possible earthquake magnitude for each of the various seismic sources. Assuming that each of these earthquakes will occur at the minimum possible distance from the site, the ground motion is calculated using appropriate Ground Motion Prediction Equations (GMPEs). Unfortunately, this straightforward and intuitive procedure is overshadowed by the complexity and the uncertainty in selecting the appropriate earthquake scenario, creating the need for an alternative methodology (probabilistic), which is free from discrete selection of 'scenario earthquakes'.  

We do not know when earthquakes will occur, we do not know where they will occur and we do not know how big they will be. PSHA takes the randomness of earthquake occurrences in space, time and magnitude into account. Thus, by incorporating the effects of various random uncertainties in the input parameters, the PSHA approach provides an avenue to arrive at a more objective and cost-effective engineering decisions.