Thickness Determination and Stability Analysis of Boundary Pillar in Transition from Open-Pit to Underground Mining of An Iron Mine
The layout of boundary pillars at the bottom of pit in open-pit mine is a common problem in transition from open-pit to underground mining.Aiming at the transition from open-pit to underground engineering of an iron mine,the thickness of the boundary pillar of the iron mine was calculated based on theoretical calculation and engineering analogy method,and the displacement and stress of the pillar in the mining process were analyzed by FLAC3D numerical simulation software.The calculation results are as follows.The reasonable thickness of the boundary pillar of the iron mine is 40 m.The blasting vibration caused by underground blasting operation had little effect on the boundary pillar.The deformation of the central rock mass of the boundary pillar had been in a small fluctuation.Although there was a certain degree of stress concentration,the maximum compressive stress and maximum tensile stress were less than the strength of the rock mass itself.The 40 m thick boundary pillar can meet the needs of mine safety production.
Transition from open-pit to undergroundThickness of boundary pillarPillar stabilityNumerical simulation
万方数据
维普
