Fig 1.
Simple sample preparation flow chart.
Fig 2.
MTS815 fully digital hydraulic servo test system.
Fig 3.
Coal specimens with different water contents.
Fig 4.
Uniaxial compression test of coal specimen.
Fig 5.
Stress–strain curves of coal rocks with different water contents:(a) Stress–strain curve of raw coal I with different water contents; (b) Stress–strain curves of raw coal II with different water contents.
Fig 6.
Trend of peak strain against water content in coal.
Fig 7.
Trend of coal compressive strength against water content.
Fig 8.
Trend of coal elastic modulus against water content.
Fig 9.
Evolutionary diagram of the entire energy process [26].
Fig 10.
Energy evolution of damage processes in coal rocks with different water contents.
(a) Energy evolution of coal rock with 0% water content. (b) Energy evolution of coal rock with 1.6575% water content. (c) Energy evolution diagram for coal rock with 2.021% water content. (d) Energy evolution of coal rock with 2.374% water content. (e) Energy evolution of coal rock with 2.972% water content.
Table 1.
Raw coal I moisture content.
Table 2.
Raw coal II moisture content.
Table 3.
Peak energy of coal rock with different water contents.
Fig 11.
Simple illustration diagram.
Fig 12.
Evolution law of initial damage value and critical damage value of coal under different water contents.
Fig 13.
Simulation curve and uniaxial compression test curve.
Fig 14.
Simulation curve and Shuangma No. 2 mine test curve comparison.
Fig 15.
Comparison of evolution law of damage variable.