基于K-G模型的根-土复合体强度特性试验研究

Experimental Study on Strength Characteristics of Root-soil Composite Based on K-G Model

利用GDS应力路径三轴仪,分别对无根素土和不同含根量的根-土复合体分别进行了等向固结试验及不同球应力条件下的等p应力路径三轴排水剪试验。基于K-G模型,探讨了含根量对根-土复合体的体变模量、体应变、剪切模量和剪应变等影响规律。研究表明:随着含根量的增大,根-土复合体的体变模量和剪切模量均得到明显增强,相应的体应变和剪应变均明显减小,并最终导致其抗剪强度得到提高。通过研究揭示了植物根系增强土体的内在机理。研究结果为进一步探索根-土复合体的强度理论奠定了试验基础,也为生态护坡工程中的强度和稳定分析提供了理论依据。

Using GDS stress path triaxial apparatus, the isotropic consolidation tests for rootless soil and root-soil composite were carried out respectively, and then for different spherical stress, a series of constant p strees path drained triaxial compression tests were also done. Based on K-G model,the influ- ence laws of root-content of root-soil composites upon bulk modulus, volume strains, shear modulus and shear strains were discussed. The research shows, along with the increase of root-content, the bulk modu- lus and the shear modulus of root-soil composite are all enhanced remarkably, and the corresponding vol- ume strain and shear strain are all decreased significantly,which eventually leads to the increase of shear strength of root-soil composites. Through the research, the intrinsic mechanism that the plant root en- hanced the soil is revealed. The research results have laid an experimental foundation for the further ex- ploration of strength theory of root-soil composites, and have also provided a theoretical basis for the strength and stability analysis of ecological slope protection project.