Instability Process of Crack Propagation and Tunnel Failure Affected by Cross-Sectional Geometry of an Underground Tunnel

<div>The result of the agreement between the contour line FAI = 4 and the process of crack depth. The results of experimental and numerical simulation of (a) T1 under 6.30 MPa and (b) T2 under 5.84 MPa.</div>

Advances in Civil Engineering

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Figure 9

Figure 9: Instability Process of Crack Propagation and Tunnel Failure Affected by Cross-Sectional Geometry of an Underground Tunnel 