In order to further investigate the deformation and strength characteristics of transversely isotropic unsaturated remolded loess under complex stress paths, three sets of 39 consolidation shear tests were conducted on transversely isotropic unsaturated soil using different experimental instruments (unsaturated true triaxial apparatus and unsaturated triaxial apparatus). The results show that: In true triaxial shear tests, the stress-strain relationship curve of the specimen exhibits strain hardening characteristics and has a hyperbolic shape, and the stress also increases with the increase of suction force.As the shearing process continues, the moisture content of the true triaxial specimen decreases continuously. Under the same b value and net confining pressure conditions, the greater the suction force, the greater the slope of the moisture content axial strain relationship curve. The true triaxial specimen, K0CD test specimen, and K0′CD test specimen consistently exhibit a state of shear shrinkage during the shear test. The magnitude of the failure stress of the test specimens under three different initial conditions is highest for the true triaxial test specimen, followed by the K0CD test specimen, and lowest for the K0′CD test specimen. The initial tangent modulus of the K0CD test specimen is the highest, followed by the K0′CD test specimen, and the true triaxial test specimen is the smallest. The research results are of great significance for promoting the study of mechanical properties of transversely isotropic unsaturated loess, improving relevant theories and criteria, and guiding engineering practice.
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