Dynamic characteristics and adaptability research of high-speed railway roadbed with silt-cement improved aeolian sand

The dynamic characteristics of silty-cement modified aeolian sand for high-speed railway subgrade have been insufficiently studied. Its engineering applicability needs to be validated.The internal acceleration distribution patterns are systematically investigated. The attenuation characteristics are analyzed through 1:10 scale laboratory model tests. The cumulative settlement changes are analyzed under dynamic loading conditions. Its engineering suitability was evaluated through comparative analysis which conducted the existing modified soil subgrade dynamic response data. Key findings are as follows: (1) The vibration energy attenuation pattern was found to align with established research. More than 50% of energy loss was concentrated in the modified layer structure. (2) A dynamic response limit of 2.49 m was reached for the modified subgrade. This result was found to be comparable to previous studies. Adequate safety margin for embankment structures was ensured. (3) The cumulative settlement under single-cycle 100,000 vibration cycles was measured at approximately 0.297 mm. Superior settlement resistance was demonstrated compared to other modified soils. However, a significant settlement increase of 0.970 mm was observed under double-cycle 100,000 cycles. Compromised deformation resistance was indicated. (4) The theoretical framework for dynamic response analysis was enriched by these findings. A technical basis was provided for implementing this innovative silty-cement modified aeolian sand system in desert fringe regions.