Study on surrounding rock stability and support design of mining gateway under influences of abandoned roadways

in order to study abandoned roadways formed by the mining in the former smal mines affected to the stebiliy of the mining gateway in the coal mining face,and selec ratonal suport method and paraneters FLAC-~(3D) sofiware was applied to the numercal analysis on the surounding rock steailiy of th transporatongateway in acoal mining face affected by the abandoned roatways under different suppor conditions when the cal mining was continuously pushed forvard.A panor?mic borehole peeing suney was conducted on the roof and surounding rock of the gatewa afer the optimized support.The resultshowed that under the infiuencesof the abandoned roadways,the redstribution ofthe stressesin the coal mining face would cause the stress concentration at the bovderline ofthe coa illar along the abandoned roadway and would cause the vertial tresses rapidly increased in the nearby mine transportation roadway and the plasic zone scope expanded.Underthe uncfion of suppor.,the plastic zone scope of the suounding rock and the surounding rock deformation co dion in the mine roadway could be obviously improved.When the abandoned roadway was in the advancestress infuence seope of the coal mining fac ,the roo and for defomation values of the gateway woud be serously increased.Under the function of the optimzed suppor lan.the transportaton roatw ay near the abandcned roadiway would have less developed cracking and well ntegation of the roof strata.