Theoretical and Experimental Study on the Mechanism of Instability and Firing Gas in Hard Quartz Sandstone

<div>Typical experimental results of different friction velocities. 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121 -12 172 -12C252 -12 337 35 337 126C337 195 286 231 210 262C166 281 126 304 126 348C126 388 152 417 191 417C240 417 274 378 294 318L319 325Z"></path></g></svg>.</span> (b) <span class="nowrap"><svg height="11.439pt" id="M6" style="vertical-align:-2.15067pt" version="1.1" viewbox="-0.0498162 -9.28833 50.1985 11.439" width="50.1985pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M219 86C216 168 211 250 206 337C201 410 189 448 163 448C131 448 79 396 43 344L60 322C91 359 110 375 118 375S132 358 136 298C141 238 152 81 155 -12H182C242 62 331 177 390 258C435 321 451 360 451 391C450 424 432 448 408 448C390 448 372 435 366 419C362 410 362 401 366 394C373 383 376 367 376 350C376 283 262 138 221 86H219Z"></path></g><g transform="matrix(.013,0,0,-0.013,9.495,0)"><path d="M535 323V373H52V323H535ZM535 138V188H52V138H535Z"></path></g><g transform="matrix(.013,0,0,-0.013,20.758,0)"><path d="M456 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Advances in Civil Engineering

fig7

Figure 7

Figure 7: Theoretical and Experimental Study on the Mechanism of Instability and Firing Gas in Hard Quartz Sandstone 