Field Detection and Numerical Simulation Study on Roof Asymmetric Fracture Mechanism of Large-Span Soft Rock Roadway with Discontinuity Surface

<div>Schematic diagram of progressive asymmetrical instability of roof of large-span roadway with discontinuous surface (<svg height="9.49473pt" id="M68" style="vertical-align:-0.2063999pt" version="1.1" viewbox="-0.0498162 -9.28833 15.197 9.49473" width="15.197pt" 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="M600 0V24L339 665L311 657L43 24V0H600ZM497 50H107L303 539L497 50Z"></path></g><g transform="matrix(.013,0,0,-0.013,8.327,0)"><path d="M499 88L487 113C459 86 422 65 413 65C403 65 403 74 409 98L461 318C487 426 460 448 431 448C408 448 383 441 352 424C305 398 223 344 157 257H155L243 674C249 702 249 712 240 712C227 712 170 680 87 673L82 648H117C155 648 162 644 150 590L23 -4L30 -12C55 -4 81 3 105 8C113 53 131 150 143 187C199 281 323 387 372 387C390 387 393 369 380 311L328 86C313 19 319 -12 347 -12C379 -12 442 24 499 88Z"></path></g></svg> is the difference of roof fracture height between regions I and II).</div>

Geofluids

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Figure 16

Figure 16: Field Detection and Numerical Simulation Study on Roof Asymmetric Fracture Mechanism of Large-Span Soft Rock Roadway with Discontinuity Surface 

Figure 16 | Field Detection and Numerical Simulation Study on Roof Asymmetric Fracture Mechanism of Large-Span Soft Rock Roadway with Discontinuity Surface 