1. Research Scholar, Dept. of Earthquake Engineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India.
2. Professor and Head, Dept. of Earthquake Engineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India (corresponding author).
3. Head, Dept. of Earthquake Hazard and Risk, Norwegian Seismic Array, P.O. Box 53, N-2027 Kjeller, Norway.