# A Study on the Creep Characteristics of Gassy Clay Mixed with Silt
## 3 Results  
### Analysis of Triaxial Shear Characteristics  
Following the triaxial shear tests, stress-strain relationship curves of the silt-containing gassy clay are plotted under various confining pressures with identical gas content and under consistent confining pressure with differing gas contents, depicted in Figure 2 (take the gas content of 14.07% and the confining pressure of 150 kPa as an example). Yield stress distribution curves of the silt-containing gassy clay are plotted under the dual influence of confining pressures and gas contents, depicted in Figure 3. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Confining Pressure** & **Gas Content** & **Deviatoric Stress** \\ \(\sigma_{3}\) **(kPa)** & **W (\%)** & **\(q\) = \(\sigma_{3}\)—\(\sigma_{3}\) (kPa)** \\ \hline \multirow{4}{*}{150} & 0 & 15–30–45–60 \\  & 8.36 & 30–60–90–120 \\ \cline{1-1}  & 14.07 & 25–50–75–100 \\ \cline{1-1}  & 25.24 & 15–30–45–60 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Loading path of test 2 (with identical confining pressure and varying gas contents). Figure 3: Yield stress distribution curves of the silt-containing gassy clay under the dual influence of confining pressures and gas contents (**a**) Yield stress–gas contents curves under different confining pressures; (**b**) Yield stress–confining pressures curves under different gas contents. Figure 2: (**a**) Conventional triaxial test curves under different confining pressures (at the gas content of 14.07%); (**b**) conventional triaxial test curves under different gas content levels (at the confining pressure of 150 kPa). An analysis of Figure 2a reveals that under four distinct confining pressures, stress increases with strain when the specimen's strain is minimal; as strain reaches a certain threshold, stress remains almost unchanged; when the strain continues to increase, the stress eventually reaches a stable state and no peak value appears, indicating that the stress-strain relationship curve of silt-containing gassy clay exhibits a characteristic strain-hardening pattern [21]. Additionally, Figure 2a underscores the significant influence of confining pressure on the stress-strain characteristics of the specimen when the gas content remains constant. Higher confining pressures correspond to greater stress levels exhibited by the specimen at identical strain levels, alongside elevated yield stress and the corresponding strain. From Figure 2b, it is evident that for the four different gas contents, as the strain on the specimen remains minimal, the stress increases proportionally with strain; as the strain reaches a certain threshold, the stress relatively stabilizes; and when the strain continues to increase, the stress eventually reaches a constant state and no peak value appears, indicating that the stress-strain curve of silt-containing gassy clay demonstrates a typical strain-hardening pattern [21]. Additionally, Figure 2b illustrates the significant impact of specimen gas content on its stress-strain relationship under identical confining pressures. Specifically, lower gas content correlates with higher stress levels at equivalent strains, resulting in increased yield stress and strain. Notably, when the gas content of the specimen is zero, stress peaks at the same strain, as do the yield stress and its corresponding strain. Comparing Figure 2a,b reveals consistent trends in the stress-strain relationship curves of the specimens. Both sets exhibit strain-hardening behavior. Notably, variations in confining pressure and gas content markedly influence the stress-strain relationship. Higher confining pressure or lower gas content results in greater stress levels at an equivalent strain, alongside elevated yield stress and strain.