External drainage structure for concealed box culvert

The utility model relates to an external drainage structure for a concealed box culvert. The utility model aims to provide an external drainage structure for a concealed box culvert, which is reasonable in structure and convenient to construct, and can ensure the stability of a backfill soil body and the box culvert while effectively draining water. According to the technical scheme, the external drainage structure for the buried box culvert is characterized by being provided with an excavated drainage ditch and the buried box culvert which is arranged at the bottom of the drainage ditch and used for meeting the requirement for pipeline laying or maintenance, and a drainage blind ditch is formed between the exterior of the buried box culvert and the drainage ditch. The drainage blind ditch is filled with a padding layer capable of ensuring that seepage water flows along the slope and is discharged out of the drainage ditch, an anti-filtration permeable layer for preventing the drainage blind ditch from being