Experimental Study on Deformation Law of Rectangular Roadway in Horizontal Layered Rock Mass

Figure 9

Evolution of vertical strain field under different loads; (a) Under load level 4; (b) Under load level 14; and (c)–(e) Under load level 23 and cumulative duration is 541 mins, 542 mins, 543 mins, and 544 mins, respectively.

(a)

(b)

(c)

(d)

(e)

(f)