Stability Mechanism and Control Factors on Equipment Removal Area under “Goaf-Roof-Coal” Structure

<table class="table-group" id="tab1"><tr><td><table class="table"><tr><td class="thead-hr" colspan="4"><hr/></td></tr><tr class="thead"><td class="align_left">Roof and floor</td><td class="align_center">Rock unit</td><td class="align_center">Min-Max (average)/<i>m</i></td><td class="align_center">Lithological characteristics</td></tr><tr><td class="thead-hr" colspan="4"><hr/></td></tr><tr><td class="align_left">Main roof</td><td class="align_center">Medium grained sandstone</td><td class="align_center">12.0–14.35 (13.15)</td><td class="align_center">Grey, light white, muddy cementation, wavy and massive bedding.</td></tr><tr><td class="align_left">Immediate roof</td><td class="align_center">Siltstone</td><td class="align_center">2.68–6.50 (4.65)</td><td class="align_center">Grey, deep grey, argillaceous cementation, horizontal bedding.</td></tr><tr><td class="align_left">False roof</td><td class="align_center">Mudstone</td><td class="align_center">0.0–0.1 (0.05)</td><td class="align_center">Grey, easy to muddy when encountering water.</td></tr><tr><td class="align_left">Floor</td><td class="align_center">Carbonaceous mudstone</td><td class="align_center">0.00–3.06 (1.02)</td><td class="align_center">Grey, muddy cementation, easy to soften when encountering water.</td></tr><tr class="table-tr"><td colspan="4"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

Advances in Civil Engineering

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Table 1

Table 1: Stability Mechanism and Control Factors on Equipment Removal Area under “Goaf-Roof-Coal” Structure 