Coal mine tunnel surrounding rock deformation characteristic combined monitoring system

The invention discloses a coal mine tunnel surrounding rock deformation characteristic combined monitoring system which comprises monitoring devices, the monitoring devices are arranged in a wide drill hole and a narrow drill hole, the wide drill hole and the narrow drill hole are formed in surrounding rock and communicate with each other, each monitoring device comprises a mounting column embedded in the narrow drill hole, each mounting column is provided with a peeping cavity corresponding to the wide drill hole, each peeping cavity is provided with a plurality of groups of monitoring pieces at equal intervals, and each group of monitoring pieces are distributed in an annular array; each monitoring piece comprises a mounting rod, a roller and a second spring, and each mounting rod penetrates through the corresponding mounting column and is in sliding connection with the mounting column. The roller makes contact with the wide drill hole to sense the deformation condition of the surrounding rock of the tunnel