Drilled hole effective extraction radius measuring method based on gas content method

The invention provides a drilled hole effective extraction radius measuring method based on a gas content method, and belongs to the technical field of coal seam gas extraction. The method comprises the following steps that (1) the gas extraction rates under the different residual gas content conditions are respectively calculated; (2) the gas extraction rate eta 5 is determined according to the regulations of the Coal Mine Gas Extraction Basic Index; (3) the gas extraction rate eta is calculated; (4) the total extraction quantity of gas is calculated; (5) the number N of extraction drilled holes is calculated; (6) the N drilled holes are evenly distributed in an extraction drilled hole control area, and the drilled hole extraction radius within certain extraction time is calculated. The effective extraction radius can guide to design the reasonable extraction drilled holes, the aim of eliminating prominent dangerousness can be achieved through the method on the premise of meeting the pre-extraction time, and a large amount of manpower and a large number of financial resources and material resources can be saved.