1. Research Scholar, Dept. of Civil Engineering, Indian Institute of Technology Guwahati, Assam 781039, India.
2. Professor, Dept. of Civil Engineering, Indian Institute of Technology Guwahati, Assam 781039, India (corresponding author).
3. Scientific Officer–G, CE & QAS/Nuclear Research Group, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India.