Triaxial test three-dimensional deformation reconstruction and measurement method

Abstract

The invention discloses a triaxial test three-dimensional deformation reconstruction and measurement method and belongs to the technical field of geotechnical experiment testing. The method is characterized in that a transparent square pressure chamber is adopted, a specially-produced rubber membrane whose label can be tracked is marked, two digital cameras at the front and at the back and a corresponding image acquisition control and processing system are employed, through tracking the position change of the angle points of the rubber membrane on an image, a certain hypothesis is adopted to obtain the space coordinate of the characteristic points of the rubber membrane on the surface of a sample, and the images acquired by the two cameras at the front and at the back are spliced so that the measurement of the three-dimensional deformation of the sample during a triaxial test process is realized. Through combination with ANSYS finite element software, a three-dimensional deformation grid and a three-dimensional whole surface strain field of the sample are obtained. The method provided by the invention has the following advantages: the comprehensive deformation characteristics of the sample in the triaxial test process can be obtained from a front direction and a back direction, and the space positions of surface characteristic points in a triaxial test can be obtained for realizing reconstruction of three-dimensional deformation of the sample, and the distribution of the three-dimensional surface strain field of the sample can be obtained.

Description

technical field [0001] The invention belongs to the technical field of experimental testing of rock and soil mechanics, and relates to a method for reconstructing and measuring the three-dimensional deformation of a triaxial sample for testing soil, gravel and soil-rock mixture. Background technique [0002] Triaxial test technology is one of the most important test techniques in rock and soil mechanics, which is widely used to study the strength, stress-strain relationship of rock and soil materials and construct constitutive models. In the traditional triaxial test, the force sensor is used to measure the stress acting on the sample, and the displacement sensor is used to measure the strain of the soil, and the macroscopic single-value stress-strain relationship of the soil is given. With the deepening and development of rock and soil mechanics research, people began to pay attention to the strain localization of the soil and the formation and development trend and change ...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a method to realize the deformation measurement and three-dimensional reconstruction of the whole surface of the sample during the triaxial test, so as to solve the problem that the existing digital image measurement technology of the triaxial test can only measure the radial and axial directions of one side of the sample. Deformation limitations, enabling 3D measurement and reconstruction of specimen deformation in triaxial tests

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