A thermo-mechanical damage constitutive model for deep rock considering brittleness-ductility transition characteristics
Chen-chen Feng, Zhi-liang Wang, Jian-guo Wang, Zhi-tang Lu, Song-yu Li
A thermo-mechanical damage constitutive model for deep rock considering brittleness-ductility transition characteristics
This paper developed a statistical damage constitutive model for deep rock by considering the effects of external load and thermal treatment temperature based on the distortion energy. The model parameters were determined through the extremum features of stress – strain curve. Subsequently, the model predictions were compared with experimental results of marble samples. It is found that when the treatment temperature rises, the coupling damage evolution curve shows an S-shape and the slope of ascending branch gradually decreases during the coupling damage evolution process. At a constant temperature, confining pressure can suppress the expansion of micro-fractures. As the confining pressure increases the rock exhibits ductility characteristics, and the shape of coupling damage curve changes from an S-shape into a quasi-parabolic shape. This model can well characterize the influence of high temperature on the mechanical properties of deep rock and its brittleness-ductility transition characteristics under confining pressure. Also, it is suitable for sandstone and granite, especially in predicting the pre-peak stage and peak stress of stress – strain curve under the coupling action of confining pressure and high temperature. The relevant results can provide a reference for further research on the constitutive relationship of rock-like materials and their engineering applications.
deep rock / crack initiation threshold / thermo-mechanical coupling / statistical damage model / distortion energy theory
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[[2]] |
JI M, CHEN K, GUO H J. Constitutive model of rock uniaxial damage based on rock strength statistics [J]. Advances in Civil Engineering, 2018: 5047834. DOI: https://doi.org/10.1155/2018/5047834.
|
[[3]] |
|
[[4]] |
|
[[5]] |
|
[[6]] |
|
[[7]] |
|
[[8]] |
|
[[9]] |
|
[[10]] |
|
[[11]] |
|
[[12]] |
|
[[13]] |
|
[[14]] |
|
[[15]] |
|
[[16]] |
|
[[17]] |
|
[[18]] |
|
[[19]] |
|
[[20]] |
ZHAO G J, CHEN C, YAN H. A thermal damage constitutive model for oil shale based on Weibull statistical theory [J]. Mathematical Problems in Engineering, 2019: 4932586. DOI: https://doi.org/10.1155/2019/4932586.
|
[[21]] |
|
[[22]] |
ZHU L J, XU X L, CAO X J, et al. Statistical constitutive model of thermal damage for deep rock considering initial compaction stage and residual strength [J]. Mathematical Problems in Engineering, 2019: 9035396. DOI: https://doi.org/10.1155/2019/9035396.
|
[[23]] |
|
[[24]] |
|
[[25]] |
|
[[26]] |
|
[[27]] |
|
[[28]] |
|
[[29]] |
|
[[30]] |
|
[[31]] |
|
[[32]] |
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