Open AccessStudy on the effect of resistivity and meso-structure evaluation of alkali solution strengthening loess: A case study
Author(s) -
Wenle Hu,
Liang Hua,
Tiehang Wang
Publication year - 2021
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.179
H-Index - 26
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/643/1/012027
Subject(s) - loess , direct shear test , materials science , fractal dimension , shear strength (soil) , electrical resistivity and conductivity , scanning electron microscope , mineralogy , composite material , shear (geology) , geotechnical engineering , geology , fractal , soil water , mathematics , soil science , mathematical analysis , electrical engineering , engineering , geomorphology
For evaluating the structure and strength of loess effectively, a series of laboratory tests were performed to investigate and compare the pore meso-structural characteristics, the shear strength and the resistivity of natural loess and loess treated with alkali solutions under 4 different concentrations. Scanning electron microscope(SEM) method, direct shear tests, electrical resistivity tests, and X-ray diffraction analysis were used to detect the changing process in strength parameters, micro-structure, and mineral composition. The evolution result of shear strength index and stress-strain characteristics of loess were analyzed. Combined the SEM micro-structure analysis and X-ray diffraction technology, the microscopic mechanism of alkali solutions and loess interaction was revealed. The results of tests show that the curves of shear stress- displacement featured as strain-hardening, and the increasing of shear strength indexes with the increasing of alkali solutions concentration. Then the relationship between the shear strength index and resistivity was established. The SEM images of LTA specimens were used to quantify the structural parameters by Image Processing Techniques. The changes of multiple structural indicators of LTA such as directionality, abundance, circularity, fractal dimension, and the orientation probability entropy were revealed. The potential mechanism of LTA was revealed by the XRD and EDS tests from the perspectives of mineral composition and chemical element composition. The results of this study show that alkali-loess interaction was the main influence factor for the changes in the shear strength and meso-structure s. The results provide a valuable implication for the construction in the loess deposits.