Mechanical State Analysis Of Backfilling Body In Subsiding Area And Optimization Of Stoping Sequence In Jinshandian Iron Mine

In the process of underground mining with sublevel caving method, surface deformationand subsidence damage become more and more significant. As a result, it is required to carry outbackfilling work in subsidence area. However, backfilling body is dynamic and soft, whichbrings risks for trucks to backfill. In order to backfill safely, it’s necessary to study the mechanicalstate of backfilling body.In the paper, ANSYS is applied to establish three-dimensional numerical model ofJinshandian Zhangfushan Iron Mine based on the mine geological survey. According to rockstrength tests, methods of engineering geological analogy with fuzzy mathematics and empiricalcoefficient reduction are used to obtain rockmass physical and mechanical parameters involvedin the simulation. In initial period and stoping process, the movement law and stress state of thebackfilling body in subsidence area are analyzed. At the same time, in order to protect stopesecurity, in every stoping scheme as designed,-312m to-410m of western orebody is stopedsections by sections in sublevels. And schemes are optimized through analyzing the status ofdisplacement, safety factors and stope stress in mining process. Finally, for impact factors ofbackfilling sinking and failure modes of backfilling transport routes, safety measures andrecommendations is put forward for backfilling.Some exploratory research is done in the paper, such as numerical simulation on miningengineering, rock mechanical analysis and mining sequence optimization, which has a certainreference value in prediction of surface subsidence form and improving backfilling security. Also,to some extent, the conclusions and suggestions can secure backfilling in subsidence area inJinshandian Zhangfushan iron mine.