Influence of Confining Pressure Unloading Rate on the Strength Characteristics and Fracture Process of Granite Using Lab Tests

<table class="table-group" id="tab2"><tr><td><table class="table"><tr><td class="thead-hr" colspan="4"><hr/></td></tr><tr class="thead"><td class="align_left" rowspan="2">Unloading rate/(MPa/s)</td><td class="align_center" colspan="3">Fitting parameters of the Mohr–Coulomb strength criterion</td></tr><tr class="thead"><td class="align_center"><i>ξ</i></td><td class="align_center"><i>σ</i><sub><i>c</i></sub></td><td class="align_center"><i>R</i></td></tr><tr><td class="thead-hr" colspan="4"><hr/></td></tr><tr><td class="align_left">Triaxial compression</td><td class="align_center">8.749</td><td class="align_center">186.477</td><td class="align_center">0.966</td></tr><tr><td class="align_left"><b>0.002</b></td><td class="align_center">7.771</td><td class="align_center">135.539</td><td class="align_center">0.961</td></tr><tr><td class="align_left"><b>0.02</b></td><td class="align_center">6.581</td><td class="align_center">147.506</td><td class="align_center">0.985</td></tr><tr><td class="align_left"><b>0.2</b></td><td class="align_center">5.641</td><td class="align_center">170.576</td><td class="align_center">0.999</td></tr><tr class="table-tr"><td colspan="4"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

<div>Linear fitting results of two strength criteria.</div>

Advances in Materials Science and Engineering

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Table 2

Table 2: Influence of Confining Pressure Unloading Rate on the Strength Characteristics and Fracture Process of Granite Using Lab Tests 