**Author details**

Gashaw Assefa1 \* and Aklilu Gebregziabher2

1 Construction Technology and Management Department, Faculty of Civil Engineering and Built Environment, Hawassa University Institute of Technology, Hawassa, Ethiopia

2 Civil Engineering Department, Faculty of Civil Engineering and Built Environment, Hawassa University Institute of Technology, Hawassa, Ethiopia

\*Address all correspondence to: onethiopia@gmail.com

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
