Preparation method of saturated soil sample in geotechnique dynamic centrifugal model test

Abstract

The invention relates to a preparation method of a saturated soil sample in a geotechnique dynamic centrifugal model test. The preparation method comprises the following steps of drying a field soil sample, crushing, and screening the field soil sample through a geotechnique sieve; calculating the needed water amount after the saturated moisture content tested by a conventional geotechnique test is increased to a certain extent, stirring and preparing the saturated soil sample in a vacuum stirring machine; uniformly loading the saturated soil sample into a model box, and embedding a porosity water pressure sensor in the soil sample; laying an isolation layer on the top of the saturated soil sample, uniformly laying dry sand with a given thickness on the isolation layer, and uniformly putting the prepared bagged dry sand on the dry sand layer; hoisting the model box, starting a centrifugal machine after the model box is fixed, and solidifying the saturated soil sample after a designed acceleration is reached; judging the stopping time through the embedded porosity water pressure sensor, stopping the machine, and hanging out the model box after the initial excess pore pressure is completely dissipated; and repeating the operation until the entire model is prepared. By adopting the preparation method, the saturation time of the soil sample can be shortened, the secondary application problem of the soil sample caused by the limit for taking soil on a field can be solved, the centrifugal solidification time can be shortened, and the solidification ending time can be accurately judged.

Description

technical field [0001] The invention relates to a method for preparing saturated soil samples, in particular to a method for preparing saturated soil samples used in geotechnical dynamic centrifugal model tests. Background technique [0002] As a typical nonlinear material, soil's stress-strain relationship and hydraulic properties are greatly affected by the stress level. In recent years, the geotechnical centrifugal test model test has been widely used in the field of geotechnical engineering because it can overcome the limitation of the accuracy of numerical methods by parameters and the defect that ordinary physical model tests cannot restore the initial self-weight stress. The gravity is simulated by the centrifugal force generated by the high-speed rotation of the centrifuge, and at the same time, the controllable ground vibration is generated by the shaking table at the bottom of the model, which can better reproduce the seismic response of the model under the actual ...

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Problems solved by technology

At the same time, when the traditional method consolidates saturated soil, it only relies on the soil's own weight and infiltration for drainage, and the consolidation time is long.

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