Research On Marco And Meso-Structural Evolution Of Remolded Expansive Soils With CT-triaxial Apparatus

In this paper, the characteristics of strength properties and meso-structure evolution of remolded expansive soil which have initial pole structure are studied in-depth with CT-triaxial shearing test. The expansive soil were taken from one site which was located in the trench slope of the Middle Route Engineering of South-to-North Water Transfer Project in China. The main research contents include the following two parts:First, through the 6 groups of triaxial shear tests, controlled 2 kinds of suction and 3 different net constant confining pressure experiments, the damage of remolded expansive soils of diameter pore is studied.Second, through the study remolded samples of the same damage degree expansive soil and different damage degree expansive soil, and control 2 different net confining pressure and 2 kinds of suction with CT-triaxial compression test. The deformation, strength properties, marco and meso-structural evolution rule of different damage status are studied also in the text.To sum up, We can draw conclusion that the pore damage has great effects on structure evolution and mechanic properties of the soil samples. And also found that different damage status has little impact on mechanical properties of remolded expansive soil. The influence of damage position is obvious. from the analysis of the 10 group tests, the expansive soil study methods reasonable confining pressure, suction level and the specific test methods of CT-triaxial compression test is very clearly.From this paper we can have a good understanding of expansive soil structure characteristic and mechanical properties. And this is very important to the further study on settlement, stability and landslide treating effect of roadbed of expansive soils.