Research on paste backfilling mining technology of coal mining under buildings,water bodies and railways

Paste back filling is one of the main back filling mining techniques to control overburden moment and prevent surface subsidence. In view of the mining problems of compressed coal resources under buildings, water bodies, railways and confined water bodies in the process of coal mining in eastern China, based on the mining conditions of the main mines in Jibei Mining Area of Zibo Mining Group, this paper analyzes the basic principles, process methods and applications of paste back filling, especially focusing on the analysis of strip coal pillar replacement mining, coal mining under high buildings and coal filling above floor confined water in Daizhuang Coal Mine. By applying the paste back filling mining technology, the ground deformation values are less than Ⅰ damage standard. Damage depth of working face under the threat of floor limestone water was just 6.0～6.5 m after paste back filling mining witch has significant effect to prevent floor water disasters. According to the future development direction of the Jibei Mining Area, research directions on paste back filling mining were proposed, such as theory and technology above floor confined water, protection of buildings under the influence of repeated mining, optimization of filling process, equipment and flow under complex conditions, combination between underground coal - gangue intelligent separation system and paste back filling mining. The research results will provide important reference for deepening application of paste back filling mining in the Jibei Mining Area.