Analysis on Wedge-shaped Roof Mechanical Behaviours under a Thick Sandstone Layer with Different Longwall Mining Speed

摘要

A mathematical model of thick rock layer with a wedge bottom was built, deducing the center of mass of wedge-shaped roof. A cantilever roof model was used to analyze the difference of the roof periodic weighting pace between horizontal strata versus wedges of different competencies. A numerical simulation model of four kinds of wedge roof with various rock properties under thick sandstone layer was created to study the mechanical behaviors solving with FLAC~(3D). These conclusions can provide theoretical and practical basis for similar mining conditions in other areas.