Abstract: Resistivity parameters related to structural properties are effective indicators of soil structure changes during compression and consolidation, and play a crucial role in quantifying these changes. We employed a modified resistivity instrument to test the vertical and lateral resistivities of Yunnan laterite during compression and consolidation. By investigating the variations of resistivity parameters (including structure factor, shape factor, and anisotropy coefficient), we aimed to analyze the changes in laterite soil structure. By using comprehensive index method and principal component analysis method, we put forward an integrated index to comprehensively evaluate the resistivity parameters related to structural properties and soil compaction. Results demonstrate that the vertical resistivity, lateral resistivity, average structure factor, and average shape factor of laterite gradually decrease as the vertical multi-stage load increases. Conversely, the anisotropy coefficients exhibit an initial decrease followed by a gradual increase to stability. Resistivity parameters indirectly reflect the structural strength and particles cementation of laterite. Additionally, the proposed comprehensive evaluation index E_R is quantitatively correlated with compactness K with high fitting accuracy. In conclusion, the proposed index proves to be a feasible tool for estimating the compactness of laterite and offers a convenient approach for the rapid evaluation of compactness in rolling projects.

Key words: laterite, resistivity, consolidation and compression, structural property, compactness