Fabricated railroad bed drain pipe

The utility model discloses an assembly type railroad bed drainage pipe, which relates to the field of civil engineering railroad bed drainage and comprises pipeline units connected end to end, a plurality of drainage ports are formed in the length direction of each pipeline unit, and every two adjacent pipeline units are connected through a connecting pipe; the pipeline unit is buried in a railway roadbed, a maintenance well is arranged in the railway roadbed, and the connecting pipe is located in the maintenance well; two clamping strips are symmetrically arranged on the inner wall of the pipeline unit and are parallel to the pipeline unit, and a detachable inner pipe piece is connected between the two clamping strips in a matched mode; the inner pipe piece comprises a plurality of inner pipe unit pieces connected in sequence, every two adjacent inner pipe unit pieces are fixedly connected through geotechnical cloth, and the open holes are formed in the inner pipe unit pieces. By means of the detachable inn