Demoulding method for soil triaxial sample

Abstract

The invention discloses a demoulding method for a soil triaxial sample, and uses a multifunctional demoulding device. The method comprises steps of: a. preparing a geotechnical solid cylindrical sample in a mold (6); b. adjusting a height of a lifting screw (51) according to a height of the sample, and tightening a restraining nut (53);c. adjusting heights of a top steel plate (15) and a middle steel plate (14), and tightening a first upper positioning nut (13), a first lower positioning nut (12), a second upper positioning nut (16), and a second lower positioning nut (17) to keep a steel frame thereof structurally stable. The demoulding method for soil triaxial sample in the invention can not only complete a release of the sample mold, but also complete an embedding of a film-receiving cylinder, the precision is high, and the sample is not disturbed. Moreover, the test method of the invention is convenient to operate, and the speed of demolding can be adjusted as needed during the demolding process.

Description

technical field [0001] The invention relates to the technical field of geotechnical engineering tests, in particular to a demoulding method for a soil triaxial sample. Background technique [0002] In geotechnical engineering research, in addition to determining the strength parameters cohesion and internal friction angle, the triaxial test is also used for the dissipation test of soil pore water pressure, static lateral pressure coefficient test, dynamic characteristic test and penetration test, etc. Compared with other soil strength test methods such as simple shear and direct shear, the results of triaxial test are closer to engineering. Since the integrity of the sample directly affects the accuracy of the test results, the integrity of the triaxial test sample after demoulding is particularly important. In the triaxial test, a three-lobe mold is often used for sample preparation. After the sample preparation is completed, demoulding is required. During the demoulding p...

AI Technical Summary

Problems solved by technology

Moreover, after the triaxial sample is removed from the mold, it is sometimes necessary to put on a rubber film of the corresponding size. If it is not vertical, the shaking of the hands of the operator can easily cause disturbance to the sample, thus affecting the test results. Therefore, a test device that can reliably install the rubber film sleeve is also needed

[0003] The invention patent with the authorized announcement number "201611021812.x" discloses "a soil sample demoulding device for triaxial compression test", which provides a manual demoulding device for triaxial sample demoulding, but it has the following deficiencies : (1) Poor applicability: the device cannot be applied to a variety of triaxial samples of different sizes at the same time, and the device needs to be greatly modified during use; (2) The demoulding quality is not ideal: the device Only one piece of three-valve valve can be removed at a time. During the experiment, a certain three-valve valve may be in too close contact with the sample to disturb the sample, resulting in poor quality or shape defects of the sample after demolding; (3) The functionality is not strong: the device can only be used for sample demoulding, and then the sample needs to be taken out to install the film holder

[0004] The invention patent with the authorized announcement number "201611243506.0" discloses "a bulldozing device for taking out hollow cylindrical soil samples", which provides a demoulding device for hollow cylindrical soil samples, but it has the following disadvantages: (1) Poor applicability: the device cannot complete the demoulding of samples of different diameters and heights with minor changes; (2) poor functionality: the device can only be used for demoulding of samples, and then the samples need to be taken out Install the rubber sleeve

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