Railway tunnel vault detection device

The utility model relates to the technical field of tunnel detection, and particularly discloses a railway tunnel vault detection device which comprises an engineering vehicle and a detection mechanism, the detection mechanism comprises a mounting base, an extension assembly, a detection radar, a supporting rod, an isolation plate, a shaft column, a locking bolt and a clamping block, and the mounting base is arranged at the upper end of the engineering vehicle; each extension assembly is arranged at one end of the mounting base, each isolation plate is fixedly connected with the corresponding extension assembly, the two ends of each shaft column are fixedly connected with the corresponding isolation plate, each locking bolt is in threaded connection with the corresponding isolation plate, and each supporting rod is rotationally connected with the corresponding shaft column. Each detection radar is fixedly connected with the corresponding supporting rod. Through the arrangement of the structure, the cambered s