Small box girder with wet joint bottom die and construction method of small box girder

The invention relates to the technical field of box girder construction, aims to solve the problems that in the prior art, the construction process is tedious and complex, the duration time is long, the safety risk is high, slab staggering, color difference and other conditions are prone to occurring, and the appearance quality of a small box girder is affected, and provides a small box girder with a wet joint bottom die. The small box girder comprises a beam body and a wet joint bottom die structure; the beam body is provided with a bottom plate, webs and a top plate, the webs comprise a first web and a second web, one side of the first web is connected with one side of the bottom plate, one side of the second web is connected with the other side of the bottom plate, and the top plate is connected with the other sides of the first web and the second web; the wet joint bottom die structure is located at the included angle of the top plate and the web plate, and the wet joint bottom die structure and the beam