Abstract
Natural disasters such as landslides often occur in Qinghai under the double deterioration of earthquake and freeze-thaw cycles, ecological slope protection is an effective way to prevent and control this type of disaster. In this paper, the mechanical properties of root-soil composites are investigated experimentally using triaxial apparatus and dynamic single shear (DSS) apparatus, and based on the discrete element method, a contact model more suitable for reinforced soil materials is proposed to study the dynamic properties of root-soil composites under cyclic shear from a fine viewpoint. Based on the results of the study, the following conclusions were drawn: 1) The presence of roots under the action of freeze-thaw cycles increases the strength properties of the soil. At the same number of freeze-thaw cycles, the shear strength and cyclic resistance of the root-soil composites are higher than those of the loess. And the strength of the root-soil composites decreases with the increase of the number of freeze-thaw cycles and then flattens out; 2) The proposed contact model can better simulate the softening effect of reinforced loess material under cyclic shear, which is more suitable for simulating the mechanical behavior of loess and laying the foundation for further study of reinforced loess material from a fine viewpoint.; 3) The presence of the root system will improve the stability of the slope soil, and the root system will have a positive effect on the shear strength of the soil when the moisture content is within a certain range. The presence of the root system also increases the cyclic resistance of the soil. Under the same cyclic shear stress conditions, the number of damage cycles of the root-soil composites is higher than that of the loess, the cumulative shear strain is less than that of the loess. However, the root system no longer exerts positive effects under saturated conditions. The research results can provide some guidance for the construction of ecological slopes in loess areas, and provide a new way to investigate the dynamic properties of root-soil composites from a fine viewpoint.
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This work was supported by Project of Qinghai Science and Technology Department, Key Research, Development and Transformation Projects in Qinghai Province. (2022-SF-159).
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Sun, Y., Li, H., Cheng, Z. et al. Experimental and Numerical Simulation Study on Mechanical Properties of Shallow Slope Root-soil Composite in Qinghai Area. KSCE J Civ Eng 27, 2834–2852 (2023). https://doi.org/10.1007/s12205-023-2366-0
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DOI: https://doi.org/10.1007/s12205-023-2366-0