System and method for measuring damage changes of mechanical properties of brittle materials under high and low temperature loading

Abstract

The invention provides a mechanical property damage change measurement system and a mechanical property damage change measurement method for fragile materials under high-temperature and low-temperature load and belongs to fragile material measurement system and method. According to the system, a temperature stress coupling and loading device, an acoustic emission signal acquisition device and an image acquisition device are additionally arranged; the temperature stress coupling and loading device is utilized, and an experiment environment is relatively close to an actual environment, such as an environment of deep rocks, so that an experiment research result has a relatively good reference value; the image acquisition device is combined with a digital image correlation technology to obtain a partial displacement field and a strain field of a test piece in a testing process; and the measurement method has the advantages of non-contact and full-field measurement, wide application, high precision, simple acquisition manner on original data, low requirements on measurement environments, and convenience for realizing automation of the whole system. The acoustic emission signal acquisition device is used for detecting the formation and evolution of cracks through measuring cracking energy, so that the damages and attenuation of the fragile materials, such as the rocks, can be described macroscopically and microcosmically under a loading environment.

Description

technical field [0001] The invention relates to a measurement system and method for brittle materials, in particular to a system and method for measuring damage changes of mechanical properties of brittle materials under high and low temperature loading. Background technique [0002] A brittle material such as rock is an extremely inhomogeneous material containing many defects such as joints, pores, cracks, fissures and faults. Deep rocks usually exhibit nonlinear mechanical properties under loading and have irreversible properties. On the other hand, in mining engineering, geotechnical engineering, and petroleum geoscience research, the underground structure is of great significance to the study of rock failure and instability process. [0003] The traditional research on the mechanical properties of rock specimens is only to measure the basic parameters (such as compressive strength, shear strength, etc.) of rock specimens through testing machines and obtain relevant inde...

AI Technical Summary

Problems solved by technology

Disadvantages of the strain electrical measurement method: the strain electrical measurement method is generally single-point or point-by-point measurement, and the global stress-strain distribution of the component cannot be obtained. It can only measure the strain on the surface of the component, and it is the average strain on the surface of the component. For the stress The surface measurement error of components with large gradient or stress concentration is relatively large, and has high requirements for the measurement environment, and any disturbance will affect the measurement results

However, due to the time-consuming and labor-intensive development and fixing operations, the experimental conditions are difficult to accurately control, and the experimental results are difficult to accurately repeat, which is not conducive to the subsequent use of computer image processing.

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