High-grade highway ultrahigh transition section with drainage function and construction method thereof

The invention provides a high-grade highway ultrahigh transition section with a drainage function and a construction method thereof.The high-grade highway ultrahigh transition section with the drainage function comprises a driving pavement, a side ditch and a middle ditch, the driving pavement comprises a drainage pavement layer, an upper pavement layer, a middle pavement layer, a lower pavement layer and a drainage device with a hollow cavity, and a first groove is dug in the upper pavement layer; a first groove is dug in the middle pavement layer, a second groove is dug in the middle pavement layer, the drainage device is contained in the second groove, the drainage pavement layer is contained in the first groove, a water inlet hole communicated with the hollow cavity is formed in the top face of the drainage device, a flow guide face arranged in an inclined mode is arranged in the hollow cavity, and a drainage opening in the declination end position of the flow guide face is communicated with the side ditc