Study on Optimized Technology of Bolt- Steel Mesh Support Parameters for Mine Pressure Bumping Roadway

According to anchor broken, bolt withdrawing and other support problems occurred in a mine pressure bumping roadway of Huating Coalfield, the analysi s showed that the available bolt support length in Huating Coalfield was less than a scope of loose circle and anchor length was about 3.5 times longer than the bolt. D ue to have poor matching between the bolt and anchor in the mine pressure bumping roadway, which led to make the mine roadway stability lost. The study results sho wed that the system kinetic energy and deformation energy born by the anchor would be reduced with the anchor length reduced and bolt length increased and anchor | ength decreased properly could be suitable to the site loose zone and plastic zone scope of the mine roadway and thus the bolt and anchor could be well matched. Ther efore, an optimization was conducted on the support parameters, the length of the bolt was increased from 2.4 mto 2.8 m and a row space distance was reduced as 0. 7mx0.8m.Thelengthoftheanchorwasdecreasedfrom7.3mand8.3mto6.5m,therowspacedistancewasdecreasedas1.0mx0.8mandayieldring,ball type backing plate and other yield devices were added. The site observation showed that the support method could effectively control the deformation of mine roadway and could basically eliminate the phenomena of anchor broken and bolt withdrawn.