From the aspect of mechanics characteristics and the tumbling mechanism of the transportation process, the force, the acceleration, the friction and the speed characteristics of asphalt mixture flow were analyzed by using theoretical mechanics and hydromechanics. The influence of the working speed and diameter-to-pitch ratio of the screw conveyor and mixing effect of the material was researched; the relation between the working speed of screw conveyor and the material conveying performance was discussed under the condition of ensuring even flow rate of material. The segregation technical reasons of asphalt mixture and improvement measures were derived. In the experiment, the full-scale test was conducted by using the AC25 mixture. And through changing the using parameters compare the paving operations, the reasonable parameter will greatly improve the uniformity of paving, and the surface proportion of structural depth of mixture decrease at 2.13-1.60. The design method of the screw conveyor with variable diameters and variable pitches is proposed, and the parametric design model of the screw conveyor with variable diameters and variable pitches is established, and which provides a theoretical basis for the structure design of screw shaft with variable diameter and variable pitch.