Triaxial sample preparation device for low-liquid limit silty soil and sample preparation method

Abstract

The invention relates to the technical field of preparation of triaxial experiment samples in rock mechanics and discloses a triaxial sample preparation device for low-liquid limit silty soil and a sample preparation method. The device comprises a sample tube, a smoothening device, a vibrator and a loading device. The method comprises the following steps: sleeving a rubber diaphragm in a split cavity; gradually pouring soil sample; controlling the initial dry density through the smoothening device and the vibrator; filling carbon dioxide and air-free water from a base until saturation; and carrying out sample consolidation process according to a secondary dry density. According to the invention, the problem of producing uniform silty soil sample is solved, the split cavity integrates the functions of positioning and sealing so as to improve the dimensional precision and the sealing effect of the sample; a rubber-steel combined vibrating head is adopted to improve the vibration and densification effect; and the matching with a current triaxial apparatus is realized, which reduces the equipment investment; and through the two-stage control of the initial dry density and the secondary dry density, the density of the sample can be optionally appointed within a certain range.

Description

technical field [0001] The invention relates to the technical field of rock and soil mechanics triaxial test sample preparation, in particular to a low liquid limit silty soil triaxial sample preparation device and a sample preparation method. Background technique [0002] Silty soil is a transitional type between sandy soil and clayey soil. It is widely distributed in my country. This type of soil has poor stability and is easy to be eroded and liquefied under various dynamic loads. In the case of natural disasters, the corresponding geological disasters seriously affect the development of the national economy and the stable life of the people, so the research on low liquid limit silty soil is urgent. Limited to the limitations of in-situ tests on site, general indoor tests are the main means of related research, and uniform samples are the necessary basis for obtaining stable and reliable test data and ensuring research results. [0003] The commonly used sample preparatio...

AI Technical Summary

Problems solved by technology

The sample preparation process of the mud consolidation method is cumbersome and requires high sample preparation equipment, and the silty soil has low clay content and poor water retention, so the water content of the mud is not easy to determine: if the mud is too thick, the air is difficult to discharge, and if the mud is too thin, the soil particles are easy to Subsidence, stratification is obvious, so this method is not suitable for silty soil

The compaction method has wide applicability, is simple and convenient, and has a short sample preparation period, but its disadvantages are also very obvious: first, the sample is subjected to impact load, the density between layers is uneven, and the lower layer of the sample is more dense; secondly, the sample preparation process The air in the middle may be encapsulated in the sample, forming large pores, resulting in large differences in the samples; third, it is too much affected by human factors during the entire sample preparation process

In addition, both methods need to cover the rubber film after the sample is made, and then place it in the test instrument for related research. During this process, the sample will be disturbed twice, which will have a potential impact on the test results.

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