Journal of Civil Engineering and Construction Technology 2141-2634 Academic Journals 10.5897/JCECT12.010 Kazeem K. Adewole Steve J. Bull * E-mail: kkadewole@yahoo.com 2012 31 03 2012 29 02 2012 3 3 116 126 This is an open-access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from https://academicjournals.org/journal/JCECT/article-abstract/EAEB9A63426 The full text article is available as a PDF file from https://academicjournals.org/journal/JCECT/article-full-text-pdf/EAEB9A63426