1. Faculty of Civil and Water Resources Engineering, Bahir Dar University, Bahir Dar, Ethiopia
2. Durham School of Architectural Engineering and Construction, University of Nebraska-Lincoln, the Peter Kiewit Institute, 1110 S 67th St., Omaha, NE 68182-0816, USA
3. College of Architecture, Art and Design, Mississippi State University, 123 – D Howell Building; Starkville, MS 39759, USA.