Sleeve type soil grasping device sensor device for measuring test soil body inside micro deformation in geotechnique direct shearing test

Abstract

The invention belongs to the technical field of geotechnical engineering, and particularly relates to a sleeve type soil grasping device sensor device for measuring the test soil body inside micro deformation in a geotechnique direct shearing test. The device consists of components such as a spoon-shaped soil grasping device, a displacement transmission rod, a sleeve, a sleeve support frame, a fixed support frame, a displacement transmission transfer joint, a displacement sensor, a fixed screw cap and a screw. The spoon-shaped soil grasping device is connected with the displacement sensor through the displacement transmission rod and the displacement transmission transfer joint; the displacement transmission rod sleeve achieves a blocking effect; the measuring precision is improved; the whole system is fixed on the outer wall of a shearing box of a geotechnique direct shearing instrument through the sleeve support frame and the fixed support frame. The spoon-shaped soil grasping deviceis buried inside the test soil body; when the test soil body deforms, the spoon-shaped soil grasping device is driven to move together, so that the micro displacement of the soil body is measured andis accurately transferred to the displacement sensor arranged outside the shearing box. A plurality of sets of the sleeve type soil grasping device sensor devices can be connected in parallel to be jointly used, and can be used for simultaneously measuring the micro deformation condition of different positions of the test soil body in the shearing box in the same geotechnique direct shearing test.

Description

technical field [0001] The invention belongs to the field of geotechnical technology, and in particular relates to a sleeve-type earth grab sensor device for measuring the micro-deformation inside the soil body in a geotechnical direct shear test. Background technique [0002] In the traditional geotechnical direct shear test, a direct shear instrument with a shear box system is generally used for the test. The test principle is to test several samples of the same soil along a fixed shear plane under different vertical pressures. Directly apply the horizontal shear force to obtain the shear stress at the time of failure, and then determine the shear strength indicators of the soil: internal friction angle and cohesion according to Coulomb's law. In geotechnical direct shear tests, the relative displacement of the upper and lower shear boxes is often used as the nominal soil deformation value, which ignores the relative displacement between the soil in the shear box and the s...

AI Technical Summary

Problems solved by technology

In geotechnical direct shear tests, the relative displacement of the upper and lower shear boxes is often used as the nominal soil deformation value, which ignores the relative displacement between the soil in the shear box and the shear box during the shearing process

Especially for large-scale geotechnical direct shear tests, the size of the shear box is larger. In the shear test, the soil in the shear box has obvious creep deformation, and the relative displacement of the upper and lower shear boxes cannot accurately represent the deformation of the soil.

At present, there are no effective instruments and test methods for measuring the internal micro-deformation of the soil in the geotechnical direct shear test, and new experimental devices and measurement methods need to be proposed

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