Construction method of fire preventing and extinguishing channel on goaf target area ground

The invention discloses a construction method of fire preventing and extinguishing channel on the goaf target area ground. The construction method comprises the following steps: step 1, vertically performing primary drilling in a sandstone layer on the goaf target area ground to form a first drill hole; step 2, installing a wall protection sleeve, and guaranteeing that a bottom opening of the wallprotection sleeve is fixed to the sandstone layer, wherein a certain gap is kept between the wall protection sleeve and the inner wall of the first drill hole to form an annular gap, and installationof the wall protection sleeve is finished until an upper opening is flush with the ground; step 3, enabling the annular gap in the step 2 to be filled with well cementation cement; and step 4, afterthe well cementation cement in the step 3 is solidified, performing secondary drilling in a goaf to form a second drill hole. The construction method has the advantages that the original procedures ofsecondary drilling and re-c