Cation Exchange Detection In The Process Of Ionic Soil Stabilizer Reinforcing Soil By Laser-induced Breakdown Spectroscopy

Landslide hazard is serious in our country, which is posing a great threat to the economicand the security of people’s life and property. As a new, convenient, fast landslide curingmethod, ionic soil stabilizer (ISS) has been widely applied, but its theoretical research haslagged far behind the practical application. This will affect its application prospect ingeological disaster prevention and the cost of the project. In addition, the traditional researchmethods are more complicated, requiring sampling and sample preparation. In this thesis,laser-induced breakdown spectroscopy (LIBS) technology was proposed, and a series ofconstructive and meaningful research of cation exchange were done. In the last, therelationship between the soil engineering properties and cation exchange capacity wasanalyzed.(1) Permeability experiment. Expansive soil samples after infiltrated were detected byLIBS. Compared with the samples added distilled water, could find that the third permeationsample had a lot of cation exchange, fully illustrated the LIBS technology can be used todetect cation exchange. In order to improve the LIBS detection capability and stability, filterpaper was used as a substrate to change liquid samples into solid samples, and achieved goodexperimental results.(2) Standard soil experiment. Seven standard soil (Kaolin clay, red clay, quartz sand andso on.) treated by ISS were detected by LIBS. The results showed that the cation exchange ofkaolin and quartz sand was weak, the cation exchange of slip soils, expansive soils,montmorillonite was strong; the ratio of1:200ISS was good for most types of soil.(3) Pressurized simulation experiment. Xiangxi river reservoir of the three Gorges has30meters fluctuations per year, in order to simulate this periodic hydrological conditions,designed a pressure device, and then different soil were studied in different simulationconditions. The results showed that, the greater pressure the ion exchange reacted faster.(4) Curing time experiment. In order to observe how long the curing effect was best, slipsoil, expansive soil and red clay reinforced for different time were studied. The resultsshowed that, the best cure time of slip soils treated by1:100ISS was20hours; the best curetime of red clay and expansive soil treated by1:100ISS was34hours; the best cure time ofexpansive soil treated by1:200ISS was48hours.(5) Relationship study between cation exchange capacity and engineering properties. Thered clay and slip soils treated by ISS of different ratio were studied, compared withengineering properties and analyzed the relationship between the cation exchange capacityand engineering properties. The analysis results showed that, the cation exchanged more andfaster the plasticity index was lower, and the engineering properties were better. These results fully illustrated LIBS technology for ISS cation exchange detection isfeasible. These relevant researches laid a solid foundation for LIBS online monitoring thelandslide dynamic changes. It also developed a new model for the research of the stability ofthe slope and disaster prevention theory.