Abstract: Based on the uncertainty of the width of the interval pillar,the fact that both sides of filling bodies and the high height in Wuzhuang Iron Mine,in order to ensure the safety and efficiency of stope interval pillar,the core design scheme of stope backfill on both sides of stope interval pillar is designed,the backfill is sampled,and the compressive strength test of laboratory test block is carried out.The test results show that the strength of the backfill in the onestep stope (pillar) conforms to the requirements of the design strength on the whole,while the strength of the twostep stope backfill is on the whole low,the width of the interval pillar in the disk section varies greatly compared with the design,and the width is extremely irregular,which is generally narrow at the top and wide at the bottom.Due to the pannel interval pillar width is irregular,two steps stope filling body strength lower than expected,excessive stope height and large area can′t be exposed during interval pillar stoping,the stoping scheme based on setting a certain thickness pillars and adopting small stope length is proposed,therefore,the sublevel stoping subsequent backfilling stoping method for small stope is designed.The design and implemtation of the scheme could provide reliable reference for the threestep interval pillar mining engineering of the other mines.

Key words: Pannel interval pillar,Filling body,Stoping,Coring,Compressive strength