Improved Nonlinear Nishihara Shear Creep Model with Variable Parameters for Rock-Like Materials

<table class="table-group" id="tab4"><tr><td><table class="table"><tr><td class="thead-hr" colspan="5"><hr/></td></tr><tr><td class="align_left">Shear stress (MPa)</td><td class="align_center">1.68</td><td class="align_center">2.24</td><td class="align_center">2.8</td><td class="align_center">3.36</td></tr><tr><td class="align_left"><svg height="9.39034pt" id="M41" style="vertical-align:-3.42943pt" version="1.1" viewbox="-0.0498162 -5.96091 11.1659 9.39034" width="11.1659pt" 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="M471 401C471 442 455 448 440 448C421 448 389 439 366 424C314 390 233 331 165 242H163L187 345C193 372 197 393 197 409C197 435 189 448 174 448C146 448 80 408 23 349L40 327C64 351 97 373 107 373C115 373 118 366 111 337L29 -4L36 -12C56 -4 83 3 110 9C123 69 136 126 150 172C227 283 336 381 377 381C392 381 396 370 379 298L326 74C290 -77 273 -172 273 -197C273 -219 316 -261 346 -261L353 -246C348 -227 352 -174 374 -66L457 310C467 352 471 381 471 401Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,6.097,3.132)"><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> (MPa·h)</td><td class="align_center">23.56</td><td class="align_center">67.65</td><td class="align_center">46.84</td><td class="align_center">0.098</td></tr><tr class="table-tr"><td colspan="5"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

<div>Initial viscosity coefficient <i>η</i><sub>0</sub> under different shear stress conditions.</div>

Advances in Civil Engineering

tab4

Table 4

Table 4: Improved Nonlinear Nishihara Shear Creep Model with Variable Parameters for Rock-Like Materials 