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Strain energy analysis of floor heave in longwall gateroads.

ABSTRACT: Floor heave in longwall gateroads is a severe issue that affects mining safety and efficiency. Researchers, however, have limited understanding on the floor heave mechanism because the deformation of post-failure rocks in the floor was seldom considered previously. In this study, we developed a theoretical model using the strain energy theory to investigate the post-failure deformation of rocks. This model was validated before being implemented into a numerical modelling package, FLAC3D, for floor heave analysis. Based on a case study of a longwall entry employing a stiff-yield pillar configuration, we observe that massive floor heave occurs at the entry rib that takes less loads (yield pillar) and eventually propagates towards the other rib bearing a significant amount of loads (stiff pillar). This observation sheds light on the floor heave mechanism in longwall gateroads and has major implications for coal mine ground control.

SUBMITTER: Wang M

PROVIDER: S-EPMC6124036 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Strain energy analysis of floor heave in longwall gateroads.

Wang Meng M Zheng Dongjie D Wang Kewei K Li Wenfeng W

Royal Society open science 20180808 8

Floor heave in longwall gateroads is a severe issue that affects mining safety and efficiency. Researchers, however, have limited understanding on the floor heave mechanism because the deformation of post-failure rocks in the floor was seldom considered previously. In this study, we developed a theoretical model using the strain energy theory to investigate the post-failure deformation of rocks. This model was validated before being implemented into a numerical modelling package, FLAC<sup>3D</su ...[more]

PMID: 30225065

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