The invention provides a high-pressure pneumatic blasting pressure relieving and transmission increasing method, comprising the steps of constructing a blasting
drill hole in a
coal layer, and carrying out high-pressure
water jet seam
cutting operation in the blasting
drill hole at intervals, so that a lead seam groove is formed in a
coal body around the blasting
drill hole; feeding a blasting steel
pipe with plugged top part into the blasting
drill hole, forming a plurality of air vents at the front part of the blasting steel
pipe, and sealing a section inside a hole opening of the blasting
drill hole by 8-10 m, so as to form a
cement plug; and connecting the blasting steel
pipe with a high-pressure air
station through a pipeline at the exposed end of the blasting steel pipe, and opening a valve arranged on the pipeline to inject high-pressure gas, so that the high-pressure gas is jetted by the blasting steel pipe from the air vents. On the basis of forming cracks and fractures formed in the fractures and
cutting grooves of the original
coal body, the high-pressure gas instantly impacts the blasting effect, so that the cracks and the fractures can be continuously expanded, and a lot of new fractures can be generated. Finally, a mutually communicated large fracture screen is formed in the coal body by using the blasting
drill hole as a center, so that the purpose of pressure relief and transmission increase of the coal body can be realized. Furthermore, the high-pressure pneumatic blasting pressure relieving and transmission increasing method has the advantages of simple operation, easiness of realization and obvious effect.