Fig 1.
Topographic map.
Fig 2.
Experimental steps.
Fig 3.
X-ray diffraction results of pattern of red sandstone for different immersion times.
(a) X–ray diffraction pattern. (b) Mineral composition content.
Fig 4.
Uniaxial mechanical test curves of red sandstone for different immersion times.
Fig 5.
The degradation characteristic curve of compressive strength of red sandstone.
(a) Deterioration curve. (b) Single order and cumulative degradation degree.
Fig 6.
Characteristic curve of degradation of elastic modulus of red sandstone.
(a) Deterioration curve. (b) Single order and cumulative degradation degree.
Fig 7.
Evolution characteristics of red sandstone strain energy.
Fig 8.
Distribution of plastic strain and elastic strain ratio before peak of rock sample.
Fig 9.
Energy evolution characteristics of rock samples.
(a) Soaking for 0 d. (b) Soaking for 30 d. (c) Soaking for 60 d. (d) Soaking for 90 d. (e) Soaking for 120 d. (f) Soaking for 150 d.
Table 1.
Energy evolution parameter values before peak of rock samples.
Fig 10.
Energy evolution parameter values before peak of rock samples.
Fig 11.
Comparison between the traditional constitutive and actual curves.
Table 2.
Experimental parameters for the constitutive mode.
Fig 12.
Evolution of damage variable of red sandstone for different immersion times.
Fig 13.
Theoretical and experimental stress–strain curves of red sandstone for different immersion times.
(a)–(f) showing water immersion times for 0, 30, 60, 90, 120, and 150 days, respectively.
Fig 14.
Sample failure characteristics under different water immersion conditions.
Fig 15.
Meso-failure structure of red sandstone with different immersion times (×5000).
Fig 16.
Schematic diagram of red sandstone deterioration due to water.