Anisotropic Soil Creep at Pure Shear

The paper presents investigations of anisotropic soil creep under pure shear in stabilometer. Pure shear is created in the following way. First, the clay soil sample is crimped in stabilometer with hydrostatic stress, and then the strain damping is added with vertical pressure with simultaneous decrease in the lateral pressure at a value two times less than vertical. The change in the sample shape occurs without the change in its volume. The volume change is controlled inside stabilometer by a small load cell created by the authors on the basis of silicon strain gauges. Tests include measurements of creep deformation of the soil skeleton with time starting from relatively instantaneous to long-term. Instantaneous deformation is determined under compression with the measurement of travel indicators using video filming. Stabilometer is used as a compression device, i.e., the sample is tested without a possibility of lateral expansion. Long-term sample deformation is recorded with time until deformation completely decays. Banded loam with a pronounced anisotropy is used for the experiment. Experimental curves of creep strain are approximated by exponential function of the creep measure. It is found that these curves should be split at least into two sections, each section being described by its own creep measure. Experimental data are not in good agreement experimental data. However, taking into account the structural soil strength will provide better agreement between experimental and theoretical results.

чистый сдвиг, анизотропный грунт, шаровой тензор напряжений, касательные напряжения, девиатор тензора напряжений, упруго-мгновенная деформация, параметры ползучести скелета грунта, мера ползучести, стабилометр, месдоза, pure shear, anisotropic soil, spherical tensor, shear stress, stress tensor deviator, elastic-instantaneous deformation, soil skeleton creep parameters, creep measure, stabilometer, load cell

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