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The cumulative deformation and fatigue failure of roadbeds induced by dynamic loads are fundamental considerations in road traffic design. To gain a more comprehensive understanding of the impact of drainage conditions and loading cycles on the performance of roadbeds composed of granite residual soil in southern China under various loading modes, this study conducted high-cycle dynamic triaxial tests using a DDS-70 dynamic triaxial apparatus. Through analysis of sample deformations, pore pressure development, and changes in critical cyclic stress ratio under different simulated waveforms, it was observed that the simulated waveform significantly influences the dynamic characteristics of the soil, with the half-sine wave proving effective in simulating the complex dynamic stress caused by traffic vehicles. Meanwhile, the study revealed uncertainties in the development of cumulative deformation under undrained conditions, thus indicating a need for dynamic tests to be conducted under drained conditions to more accurately replicate the effects of traffic loads. Additionally, the deformation of samples at 1000 cycles can serve as a crucial reference for estimating final deformation, which is essential for determining sample types and obtaining key parameters of foundation soil. This approach can help reduce testing workload and save time and costs.

来源平台：GEOTECHNICAL AND GEOLOGICAL ENGINEERING