Numerical Simulation of the Stress Field in Repeated Mining of Coal Seams Based on <i>In Situ</i> Stress Measurement

<table class="table-group" id="tab5"><tr><td><table class="table"><tr><td class="thead-hr" colspan="6"><hr/></td></tr><tr class="thead"><td class="align_left">Lithology</td><td class="align_center"><i>σ</i><sub><i>c</i></sub> (MPa)</td><td class="align_center"><i>c</i><sub>1</sub></td><td class="align_center"><i>c</i><sub>2</sub></td><td class="align_center"><i>c</i><sub>3</sub></td><td class="align_center"><i>c</i><sub>4</sub></td></tr><tr><td class="thead-hr" colspan="6"><hr/></td></tr><tr><td class="align_left">Hard rock strata</td><td class="align_center">&gt;40</td><td class="align_center">2.1</td><td class="align_center">16</td><td class="align_center">1.2</td><td class="align_center">2</td></tr><tr><td class="align_left">Medium-hard strata</td><td class="align_center">20–40</td><td class="align_center">4.7</td><td class="align_center">19</td><td class="align_center">1.6</td><td class="align_center">3.6</td></tr><tr><td class="align_left">Soft strata</td><td class="align_center">&lt;20</td><td class="align_center">6.2</td><td class="align_center">32</td><td class="align_center">3.1</td><td class="align_center">5</td></tr><tr class="table-tr"><td colspan="6"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

<div>Mining height and strength coefficient of the roof.</div>

Mathematical Problems in Engineering

tab5

Table 5

Table 5: Numerical Simulation of the Stress Field in Repeated Mining of Coal Seams Based on <i>In Situ</i> Stress Measurement 

Mathematical Problems in Engineering

Numerical Simulation of the Stress Field in Repeated Mining of Coal Seams Based on In Situ Stress Measurement

Table 5