The invention provides an in-situ cold recycling construction method for a premixed foamed
asphalt base layer and a
subbase layer, and relates to the technical field of
road engineering. The method sequentially comprises the following steps: S1, closing traffic; S2, preparing an original road; S3, putting a regeneration
train unit in place; S4, performing premixing, adding and paving; S5, performing milling and mixing by a cold regenerator; S6, paving a regenerated mixture; S7, performing
grinding; S8, carrying out joint treatment; and S9, maintaining the product. According to the method, thedemand quantity of gravels, mineral
powder,
cement and foamed
asphalt according to the quantity of recycled aggregate milled on the original path, the mixing
water demand quantity of a premixed additive is calculated and determined in combination with the optimal
water content of a recycled mixture; and pre-mixing the calculated and determined required amount of water, powdery
cement, gravel aggregate and mineral
powder to form the premix additive. Therefore, the
powder cement is prevented from drifting away, the cement, the
crushed stone aggregate and the mineral powder with the optimal ratioare effectively added, and the optimal
water content of the recycled mixture and the quality of the foamed
asphalt are also ensured, so that the recycled mixture has high-
quality performance indexes.