Experimental Study on Deformation and Acoustic Emission Characteristics of Arch Roadway under Different Unloading Rates

Figure 10

Failure modes of specimens under different initial geostresses and unloading rates. (a) Rapid unloading under 10 MPa. (b) Slow unloading under 10 MPa. (c) Rapid unloading under 20 MPa. (d) Slow unloading under 20 MPa. (e) Rapid unloading under 30 MPa. (f) Slow unloading under 30 MPa.

(a)

(b)

(c)

(d)

(e)

(f)