Construction method for open-graded asphalt concrete overlay of expressway

The invention relates to the technical field of road engineering, and discloses a construction method of an expressway open-graded asphalt concrete overlay, which comprises the following steps: step 1, preparation before construction, including preparation and preparation of open-graded asphalt concrete; secondly, the road surface is treated before construction; step 3, overlay: paving the asphalt concrete prepared in the step 1 on the pavement treated in the step 2; step 4, rolling and maintaining the pavement paved in the step 3; according to the method, the original pavement is subjected to heating pretreatment, so that the cooling rate after the heated asphalt concrete is in contact with the preheated original pavement is reduced, the heated asphalt concrete is prevented from being cooled too fast, the asphalt concrete overlay and the original pavement are thermally bonded, the bonding area of the asphalt concrete and the pavement is increased, and the adhesiveness is enhanced; the effective paving and ro