Experiment method for observing three-dimensional square crack damage and strain field as well as experiment apparatus thereof

Abstract

The invention relates to an experiment method for observing three-dimensional square crack damage and a strain field as well as an experiment apparatus thereof. The method combines a particle image velocity measurement method and a compression test, employs artificial injection mold to produce a three-dimensional built-in square crack test piece, uniform tracer particles can be subjected to layered incorporation, the damage characteristic of the three-dimensional built-in square crack under single-shaft compression can be observed and the strain field visualization is realized, the understanding on the three-dimensional built-in crack fracture damage is increased, and the method is simple and easy to carry out, and cost is low. The experiment apparatus employs a brittle and transparent resin material to simulate the practical condition of the practical rock crack, and can determine the strain field by aiming at the three-dimensional built-in square crack test piece.

Description

technical field [0001] The invention relates to the technical fields of surveying and mapping and geotechnical engineering, in particular to an experimental method and an experimental device for observing three-dimensional square crack damage and strain field. Background technique [0002] From the rock fracture mechanism of the earthquake source, the destruction of civil engineering and nuclear mine engineering, the exploitation of oil and gas, and the storage and isolation of nuclear waste, all of them are closely related to the law of crack expansion in rocks. During the construction process of large-scale rock mass engineering or when the external load changes, new cracks often initiate from the tip of the original crack, expand and even penetrate with adjacent cracks, and finally lead to the destruction of the entire rock mass. The strength reduction of rock mass caused by crack expansion not only affects the stability of rock mass, but also can lead to many engineering...

AI Technical Summary

Problems solved by technology

Nevertheless, the problem of 3D crack propagation has not been well resolved

Lin Peng, Zhou Yaneng, Li Zichang, et al. from the Department of Water Conservancy, Tsinghua University (Lin Peng, Zhou Yaneng, Li Zichang, et al. Experimental research on rock failure with three-dimensional preset single crack defects[J]. Journal of Rock Mechanics and Engineering, 2008, 27( s2): 3882-3887.) Use the developed electro-hydraulic servo dynamic and static triaxial testing machine to carry out the rock failure test research under the triaxial condition with three-dimensional preset single crack defect, and use CT scanning technology to observe the damage and destruction process of the sample. strain field

Accurate measurement and evaluation of the compression macro-failure characteristics of 3D built-in fractures and the visualization of strain fields are frontier issues of general concern at present, and it is a powerful means to promote the development of 3D fracture expansion. However, the development of existing experimental techniques is very limited and cannot accurately observe 3D fracture failure mode

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