Quantitative Visualization Monitoring of Cracks at Shotcrete-Rock Interface Based on Acoustic Emission

<table class="table-group" id="tab5"><tr><td><table class="table"><tr><td class="thead-hr" colspan="4"><hr/></td></tr><tr class="thead"><td class="align_left">Specimen</td><td class="align_center"><i>f</i><sub><i>t</i></sub> (MPa)</td><td class="align_center"><i>G</i><sub><i>f</i></sub> (N/m)</td><td class="align_center"><svg height="9.25202pt" id="M11" style="vertical-align:-3.29111pt" version="1.1" viewbox="-0.0498162 -5.96091 14.0106 9.25202" width="14.0106pt" 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="M689 332C689 394 670 448 646 448C620 448 597 421 597 396C597 386 600 381 608 372C619 359 620 334 620 315C620 150 538 45 454 45C414 45 386 67 386 122C386 138 388 158 394 180L457 426L452 432L377 416L315 156C302 100 259 45 216 45C176 45 148 67 148 122C148 133 152 158 156 180C162 212 173 259 194 332C201 357 206 384 206 405C206 430 198 448 174 448C125 448 66 406 23 342L43 319C84 368 110 383 121 383C126 383 128 382 128 377C128 370 127 359 122 343C99 268 84 204 77 156C74 137 70 111 70 104C70 25 125 -12 180 -12C228 -12 276 12 319 50C338 8 378 -12 418 -12C549 -12 689 166 689 332Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,8.931,3.132)"><path d="M245 635C92 635 37 457 37 312C37 149 91 -12 244 -12C395 -12 449 166 449 312C449 469 395 635 245 635ZM243 598C332 598 358 454 358 312C358 173 334 26 245 26C158 26 128 174 128 313S152 598 243 598Z"></path></g></svg> (mm)</td></tr><tr><td class="thead-hr" colspan="4"><hr/></td></tr><tr><td class="align_left">HB</td><td class="align_center">2.11</td><td class="align_center">35.48</td><td class="align_center">0.132</td></tr><tr><td class="align_left">HC</td><td class="align_center">2.70</td><td class="align_center">53.98</td><td class="align_center">0.153</td></tr><tr><td class="align_left">HD</td><td class="align_center">2.92</td><td class="align_center">84.12</td><td class="align_center">0.173</td></tr><tr><td class="align_left">SD</td><td class="align_center">2.26</td><td class="align_center">95.59</td><td class="align_center">0.254</td></tr><tr class="table-tr"><td colspan="4"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

<div>Calculation results of critical crack opening displacement.</div>

Structural Control and Health Monitoring

tab5

Table 5

Table 5: Quantitative Visualization Monitoring of Cracks at Shotcrete-Rock Interface Based on Acoustic Emission 