The creep behavior of rock shear seepage under different seepage-water pressures

• Published in: Mechanics of time-dependent materials 2023-06, Vol.27 (2), p.351-365
• Main Authors: Li, Guanghe, Wang, Yanting, Wang, Dong, Wang, Laigui, Zhang, Shipeng, Li, Cunjin, Teng, Ruixue
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Classical Mechanics; Correlation coefficients; Creep (materials); Curve fitting; Elastomers; Engineering; Engineering geology; Mathematical models; Parameters; Plastic bodies; Polymer Sciences; Pressure effects; Rock masses; Seepage; Shear strain; Shear stress; Solid Mechanics; Stability analysis; Viscoelasticity; Water damage; Water pressure
• ISSN: 1385-2000; 1573-2738
• DOI: 10.1007/s11043-023-09601-3

The long-term compression–shear–seepage coupling of rock mass is a cause of many engineering geological disasters. This study aimed to explore the creep characteristics of rock mass under different seepage conditions. Based on the shear-creep–seepage test results of shale, the shear-creep–seepage model considering damage was constructed using a series connection of the elastomer (H), a nonlinear viscoelastic body with nonlinear function λ (NVEP), a viscoplastic body with seepage switch S (VPB), and a viscoelastic–plastic body considering damage (VEPB). The variation law of the model parameters was analyzed, and the results showed that the model effectively described the entire change process of rock-creep characteristics, notably the deformation law of the accelerated-creep stage. The correlation coefficient R 2 was greater than 0.98, and the fitting curve was highly consistent with the experimental data. Furthermore, the greater the seepage-water pressure, the smaller the shear stress applied in the corresponding test of each stage, and the greater the cumulative shear strain of each stage. Moreover, the seepage-water pressure had a damaging effect on the mechanical strength of the rock samples. The parameter values k 1 and λ were negatively correlated with seepage-water pressure and shear stress, whereas the parameter values k 2 and η 1 were negatively correlated with seepage-water pressure and positively correlated with shear stress. The results of this study can provide theoretical support for the research and analysis of rock-mass engineering stability under long-term seepage conditions.