Abstract

The main problems of the institutes concerning with the highways in Iraq, that almost highways network are old and have along years in services without taking in view of points the explosion extension that happen after 2003 in level of numbers, weight, types of vehicles that use the roads and un-normal environments subjected to it the highway structures, as well as the other sides of live in general. Therefor it is a huge important to work hard in maintenance affectations for these great projects in order to elongated their design lives.The current research represent first step to definition the beast ways that can be depended in overlay design, where, in Iraq, the Asphalt Institute Manual (MS-17) depend in overlay design while the American Association of State Highway and Transportation Officials, (AASHTO) depended in pavement design, which have an effect on the performance of the pavements that have a great effect on the services presented by the highway. Four highway segments in the middle district in Iraq, were chosen as a case study for overlay design depending on both procedures of design with comparison.