Research on the Nonlinear Characteristics of Acoustic Emission and Damage Mechanism of Gassy Coal under Unloading Conditions

<table class="figure-group"><tr class="fig-image" id="a"><td><object data="https://static-preview.hindawi.com/articles/geofluids/volume-2022/5033940/figures/5033940.fig.005a.svgz" name="5033940.fig.005a" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(a) </b>Gas pressure 0 MPa</td></tr><tr class="fig-image" id="b"><td><object data="https://static-preview.hindawi.com/articles/geofluids/volume-2022/5033940/figures/5033940.fig.005b.svgz" name="5033940.fig.005b" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(b) </b>Gas pressure 0.2 MPa</td></tr><tr class="fig-image" id="c"><td><object data="https://static-preview.hindawi.com/articles/geofluids/volume-2022/5033940/figures/5033940.fig.005c.svgz" name="5033940.fig.005c" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(c) </b>Gas pressure 0.5 MPa</td></tr><tr class="fig-image" id="d"><td><object data="https://static-preview.hindawi.com/articles/geofluids/volume-2022/5033940/figures/5033940.fig.005d.svgz" name="5033940.fig.005d" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(d) </b>Gas pressure 0.8 MPa</td></tr></table>

<div>Time series characteristics of acoustic emission under different gas pressures.</div>

Geofluids

fig5

Figure 5

Figure 5: Research on the Nonlinear Characteristics of Acoustic Emission and Damage Mechanism of Gassy Coal under Unloading Conditions 