Study on Technology of Gateway Retained Along Goaf with No Gateway Sidewall Backfill in Thin Seam

In order to solve the support difficulties of the gateway retained along goaf with no gateway sidewall backill,with the theoretical analysis on the surround ing rock structure of the gateway and the support principle of the gateway retained along goaf,the single prop was replaced to the dense timber supports and the crossi ng articulated beam support method were applied to the design study of the support parameters.Thus coal rejects flowed into the gateway would naturally form coal reje ct stacks at the gateway sidewalls to support the roof of the gateway and the construction technique was simplified.The site measuring method was applied to the analy sis study on the support effect.The practice results showed that the support means effect was obvious,the max deformation value of the roof and floor in the gateway ret ained along goaf could be controlled within 800 mm,the max deformation value of the two sidewalls could be controlled within 600 mm,and the support effect was excel ent.