Anti-cracking air-return vertical shaft

The invention discloses an anti-cracking air-return vertical shaft, and solves the problem that an existing air-return vertical shaft is easy to crack. The anti-cracking air-return vertical shaft comprises a conical upper lock ring beam reinforcing cage (4) is arranged in the shaft wall of a cylindrical air-return vertical shaft (1) above a fan drift connecting port (3), an invertedly-conical lower lock ring reinforcing cage (8) is arranged in the shaft wall of the cylindrical air-return vertical shaft (1) below the fan drift connecting port (3), a front vertical-column reinforcing cage (12) is arranged in the shaft wall of the cylindrical air-return vertical shaft (1) in front of the fan drift connecting port (3), and a rear vertical column reinforcing cage (13) is arranged in the shaft wall of the cylindrical air-return vertical shaft (1) behind the fan drift connecting port (3). A hidden beam and column structure is added in the shaft wall of the air-return vertical shaft in a coal mine, so that cracking of the shaft is effectively avoided.