Study on the Creep Behaviors of Interactive Marine-Terrestrial Deposit Soils

Abstract

The interactive marine-terrestrial (IMT) deposit soils were formed in the complex depositional environment; their mechanical properties are different from the other deposits. The creep behaviors of Dalian clayey soils were studied according to one-dimensional creep tests and drained triaxial creep tests. Based on the creep test results, the empirical model was established to describe the one-dimensional creep behavior and triaxial creep behavior, respectively. The results showed that Dalian deposits have typical nonlinear creep behavior. With the increasing of consolidation pressure, the strain is increased, the stability time is extended, and the demarcation point between primary and secondary consolidation is more obvious. The deposits belong to medium to high secondary compressibility soil, and the secondary consolidation coefficient is decreased with the increasing of consolidation time and increased with consolidation pressure increasing. The ratio between secondary consolidation coefficient and compression index at different depths changes from 0.033 to 0.058, which conform to Mesri conclusion. Under low deviator stress, the creep processes showed the characteristic of attenuation creep and shear contraction. However, it showed the characteristic of acceleration creep, shear contraction, and shear dilatancy under damage deviator stress. The axial strain rate decreased with the increasing of creep time and increased with the deviator stress increasing, while the deviator stress has little effect on the m values. The tests results agree well with the calculation results, which showed that the creep equation is suitable for describing the creep behaviors of Dalian interactive marine-terrestrial deposits.