Abstract: In view of the issues of a copper mine in east China,such as roof breaking,easy roof fall,rich water and floor water inrush,and based on the original mining with pillar layered backfill,a new scheme of mechanized backfill mining is put forward.This scheme takes full advantages of the upward horizontal cut and fill method,which can reduce ore loss and dilution rates,effectively control ground pressure and prevent mine disasters such as roof collapse,wall caving and water bursting.Combined with the characteristics of mechanized mining,such as high production efficiency,low cost,safe operation of mining and a good working environment,the mechanized upward horizontal cut and fill method is adopted.The interval filling by cemented filling with unclassified tailings filling is applied to realize continuous mining,and the component of cemented filling are the composite high-water-content and quick-setting materials and tailings.The production results showed that the new method make mining efficiency enhanced by one-third,the recovery rate increased by 4% and the ore dilution rate reduced by 0.4%.Also it provides well guarantee for the mine work safety,and effectively solves the problems of the mine roof fall,water inrush,and low production efficiency.It can be used as a reference for design and construction of other similar mine.

Key words: Roof broken, Water-rich mine, Mechanized mining, Filling mining