Mechanical Properties and Damage Behavior of Rock-Coal-Rock Combined Samples under Coupled Static and Dynamic Loads

Figure 7

Evolution laws of loading and unloading elastic modulus of RCRCS.

(a) Group A: 1a1-A1

(b) Group B: 1a1-B2

(c) Group C: 1a1-C2

(d) Group D: 1a1-D2