Study on accumulation deformation characteristics of silty clay based on dynamic triaxial tests

Silty clay is a common compressible soil found in many engineering projects, where its deformation behavior is particularly complex under cyclic loading. This study uses the GDS dynamic triaxial testing system to examine how silty clay deforms under different moisture contents, confining pressures, and cyclic stress ratios (CSR). The results show that the cumulative strain of silty clay follows a three-phase pattern: an initial rapid increase (N = 0-300), followed by a slower rise (N = 300-1000), and finally reaching a stable state (N > 1000). Among the factors tested, CSR has the most significant impact on cumulative strain, with moisture content coming second, while confining pressure has a relatively minor effect. After 1000 cycles, cumulative strain shows a clear linear growth trend. Linear fitting analysis indicates that the uncertainty in the fitted curve is influenced by moisture content, confining pressure, and CSR. Uncertainty is greater at both low and high moisture content levels, while it is lower under moderate moisture conditions. These findings provide valuable insights into predicting soil deformation in engineering applications, helping to improve our understanding of silty clay behavior under cyclic loading.