Abstract: In order to realize the resource utilization of rice husk ash, rice husk ash was incorporated into the soil for improving the soil strength. Large-scale dynamic triaxial tests were carried out on rice husk ash modified soil. The effects of rice husk ash dosage, dynamic stress amplitude and reinforcement method on the cumulative axial deformation, dynamic stress-strain curve and dynamic elastic modulus of the rice husk ash modified soil were analyzed. The results showed that with the increase of rice husk ash content, the maximum dry density of rice husk ash modified soil decreases and the optimal moisture content increases. The content of rice husk ash has a significant influence on the performance of soil. Under the content of 5%−10% rice husk ash, the cumulative axial deformation of rice husk ash modified soil is low, and the soil strength is better. The dynamic stress amplitude and reinforcement method obviously influence the cumulative axial deformation of rice husk ash modified soil. As the number of cycles increases, the hysteresis loop area of the sample decreases and the dynamic elastic modulus increases gradually. Reinforcement materials can improve the performance of soil. For single-layer reinforcement scenario, grid reinforced soil samples surpass other samples in terms of performances.

Key words: rice husk ash, reinforced soil, large dynamic triaxial tests, cumulative axial deformation, dynamic stress-strain curve, dynamic elastic modulus