In the fields of nuclear waste geological deposit, geothermy and deep mining, the effects of temperature on the mechanical behaviors of soft rocks cannot be neglected. Experimental data in the literature also showed that the structure of soft rocks cannot be ignored. Based on the superloading yield surface and the concept of temperature-deduced equivalent stress, a thermo-elastoplastic model for soft rocks is proposed considering the structure. Compared to the superloading yield surface, only one parameter is added, i.e. the linear thermal expansion coefficient. The predicted results and the comparisons with experimental data in the literature show that the proposed model is capable of simultaneously describing heat increase and heat decrease of soft rocks. A stronger initial structure leads to a greater strength of the soft rocks. Heat increase and heat decrease can be converted between each other due to the change of the initial structure of soft rocks. Furthermore, regardless of the heat increase or heat decrease, a larger linear thermal expansion coefficient or a greater temperature always leads to a much rapider degradation of the structure. The degradation trend will be more obvious for the coupled greater values of linear thermal expansion coefficient and temperature. Lastly, compared to heat decrease, the structure will degrade more easily in the case of heat increase.
Accepted:
Published online:
Zuoyue He 1, 2; Sheng Zhang 1, 2; Jidong Teng 1, 2; Yonglin Xiong 3
@article{CRMECA_2017__345_11_752_0, author = {Zuoyue He and Sheng Zhang and Jidong Teng and Yonglin Xiong}, title = {A thermo-elastoplastic model for soft rocks considering structure}, journal = {Comptes Rendus. M\'ecanique}, pages = {752--763}, publisher = {Elsevier}, volume = {345}, number = {11}, year = {2017}, doi = {10.1016/j.crme.2017.07.002}, language = {en}, }
TY - JOUR AU - Zuoyue He AU - Sheng Zhang AU - Jidong Teng AU - Yonglin Xiong TI - A thermo-elastoplastic model for soft rocks considering structure JO - Comptes Rendus. Mécanique PY - 2017 SP - 752 EP - 763 VL - 345 IS - 11 PB - Elsevier DO - 10.1016/j.crme.2017.07.002 LA - en ID - CRMECA_2017__345_11_752_0 ER -
Zuoyue He; Sheng Zhang; Jidong Teng; Yonglin Xiong. A thermo-elastoplastic model for soft rocks considering structure. Comptes Rendus. Mécanique, Volume 345 (2017) no. 11, pp. 752-763. doi : 10.1016/j.crme.2017.07.002. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/j.crme.2017.07.002/
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