تصميم خلطة التكسية السطحية الإسفلتية

The asphalt mixture is a cohesive mass of aggregates with different grades, coated with ordinary or modified asphalt with air voids. The asphalt mix is used in paving and maintaining roads, squares, airports, car parking, etc. Aggregates are a major element in forming the structural structure of the mixture, and asphalt is the binding material for the mixture components. In this study, the asphalt surface dressing mixture was designed. It is a homogeneous mixture of aggregates with different grades and specific ratios of aggregates coated with asphalt using the Marshall method, which is applied to hot asphalt paving mixes using solid asphalt. This method is considered one of the most effective methods used in designing the asphalt mixture, due to its ease and the availability of its equipment. Two grades of aggregates with sizes (5mm-10mm) and asphalt were used according to the requirements of the surface asphalt mixture approved by the Libyan Roads and Bridges Authority. All laboratory tests were conducted on the aggregate to ensure its quality, and then experimental mixtures with seven different bituminous contents (4.50, 5, 5.50, 6, 6.50, 7, 7.50%) were conducted and tested using the Marshall method in order to obtain the optimal bituminous content (O.B.C) used in designing the surface dressing mix, which gave good results according to the specifications, and this mixture is considered suitable for use in pedestrian sidewalks instead of ordinary cement concrete, bicycle lanes, road shoulders, some stations, and light-traffic lanes, as it is spread automatically to a thickness of 5cm on a layer of granular base ranging in thickness from 15cm to 20cm, due to its rapid implementation and low economic cost. Keywords: Asphalt mixture, Optimal bituminous content (O.B.C), Aggregate grades.