الفهرس 
Table of contentsOnly 14 pages are availabe for public view
 |  | from | 281 |  |  |
| | | from | 281 | | |
Abstract
the surface layer may be considered as most important layers, because it carries most of the :win. Also, it is subjected to weathering effects such as
-w-in and temperature changes in the atmosphere. Load, rain and
changes are the main factors that cause defects in
so most researchers directed their efforts to improve the
layer’s mixtures and increase their efficiency.
Mary methods were employed to improve the surface layer such
a good type of asphalt, adding some additives to the asphalt 116 its quality, using aggregates with high strength and using woo types of mineral filler such as cement, hydrated lime, coke coal a certain performance level, the pavement cost as a portion
of the total highway cost is considered to be a governing in choosing
type of pavement to be used at a certain location. In this
connection, hot asphalt concrete mixes have proven to be of inestimable These mixes consist of asphalt cement and aggregates.