Application and Progress of Scanning Electron Microscope Testing Technology in Geotechnical Engineering.

Environmental geotechnical engineering is a new discipline which closely combines geotechnical engineering with environmental science. It mainly applies the viewpoint, technology and method of geotechnical engineering to serve for harnessing and protecting the environment. Dispersed soils are one of the special soils that have attracted much attention in geotechnical engineering in recent years, it has the characteristics of low erosion resistance and is easy to cause harm to water conservancy projects. In this paper, the progress of scanning electron microscopy (SEM) in geotechnical engineering is reviewed. The preparation and testing methods of samples, the dynamic monitoring method of microstructure changes, and the quantitative analysis technology of scanning electron microscopy are included. In view of the complexity of the traditional test methods for distinguishing dispersed soils and the contradiction between the results of the test, this paper is based on the theoretical knowledge of soil mechanics, soil electricity, soil physics and soil chemistry, TH2827C digital AC bridge, pinhole tester, debris tester, unconfined compressive strength tester and scanning electron microscope were used. The effects of temperature, water content, porosity, and saturation, lime content and curing age on resistivity, dispersion, strength and microstructure of soil samples were analyzed. Scanning electron microscopy (SEM) analysis shows that with the increase of lime content and curing time, the modified soil particles tend to be rounded from thin sheet, and the aggregate structure gradually increases, the contact mode between soil skeleton units has changed from point-to-point contact and face-to-face contact to face contact. [ABSTRACT FROM AUTHOR]