Study on Lateral Unlaoding of Tianjin Soft Dredger Soil by True Triaxial Text

In order to conduct the research on deformation properties of unloading of pit excavation,a series of true triaxial tests were performed in tianjin soft dredger fills under the condition of unconsolidated-undrained with rigid-flexible composite true triaxial apparatus, it keeps that major principle stress fixed and intermediate principal strain ε₂≈0 and minor principle stress decreased. The results indicated that tangent compression modulus increases with increasing of compression stress, stress-strain relation ε₁ and ε₃ is linearity, poisson ratio is not match with classical soil mechanics theory,μ₃₁>0.5 and increases with increasing of compression stress, pore water pressure increases at first then decreases.