1. Senior Lecturer, School of Engineering, Coventry Univ., Priory St., Coventry CV1 5FB, U.K. (corresponding author).
2. Professor of Civil Engineering, School of Civil Engineering, Univ. of Nottingham, University Park, Nottingham NG7 2RD, U.K.
3. Teaching and Research Fellow, School of Civil Engineering, Univ. of Nottingham, University Park, Nottingham NG7 2RD, U.K.