CN205175809U - Damage of mechanics characteristic changes measurement system under high low temperature load of brittle material - Google Patents

Damage of mechanics characteristic changes measurement system under high low temperature load of brittle material Download PDF

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CN205175809U
CN205175809U CN201520978760.XU CN201520978760U CN205175809U CN 205175809 U CN205175809 U CN 205175809U CN 201520978760 U CN201520978760 U CN 201520978760U CN 205175809 U CN205175809 U CN 205175809U
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acoustic emission
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刘峰宇
彭维红
张骥
张海翔
杜梦琳
曹国华
程红梅
张志镇
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China University of Mining and Technology CUMT
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Abstract

The utility model provides a damage of mechanics characteristic changes measurement system under high low temperature load of brittle material, belongs to brittle material measurement system. This system has increased temperature stress coupling loading device, acoustic emission signal collection system and image collection system, utilize temperature stress coupling loading device, experimental environment more can be close actual environment, for example the environment that the deep rock was located for experiment results more has reference value, utilize image acquisition device to combine the digital image correlation technique to obtain local displacement field and the strain field of test piece in the process of the test, this methods of measurement have non -contact, the whole audience measure, use wide, the precision is high, to original data's collection mode simple, measure and require the environment to hang down, be convenient for to realize entire system's automation. Utilize acoustic emission signal collection system, detect the formation and the evolution in crack through the energy release of measuring the fracturing for the damage of brittle material under the loading environment for example rock and decay can be described under macroscopic view and microcosmic.

Description

脆性材料高低温加载下力学特性损伤变化测量系统Measuring system for damage change of mechanical properties of brittle materials under high and low temperature loading

技术领域technical field

本实用新型涉及一种脆性材料测量系统,特别是一种脆性材料高低温加载下力学特性损伤变化测量系统。The utility model relates to a brittle material measurement system, in particular to a brittle material damage change measurement system for mechanical properties under high and low temperature loading.

背景技术Background technique

岩石等脆性材料是一种极其不均匀材料,包含很多缺陷如节理、孔、裂缝、裂缝和断层。深部岩石通常在加载下表现出非线性的力学性质并且具有不可逆的特性。另一方面,地下结构在采矿工程,岩土工程,石油地球科学研究中,对岩石破坏失稳过程的研究有非常重要的意义。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.

传统的岩石试件力学特性研究仅仅是通过试验机对岩样试件进行基本的参数的测定(如抗压强度、抗剪强度等)和借助声发射检测技术获得相关的指标特征。深部岩石所处的环境是比较复杂的,是在不同的温度场以及不同的应力状态下,这就使得岩石(岩体)这种非均质的各向异性的材料的性质更加复杂,所以在室内试验研究进行岩石力学实验时,考虑温度和应力的耦合效应对岩石力学性质的影响是必不可少的,利用高低温环境箱或者高温炉可以在室内实验时进行实时或者高温后的岩石力学实验,这样使得实验环境更能接近深部岩石所处的环境,也使得实验研究结果更具有参考价值。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 index characteristics with the help of acoustic emission detection technology. The environment in which deep rocks are located is relatively complex, under different temperature fields and different stress states, which makes the properties of rocks (rock masses), which are heterogeneous and anisotropic materials, more complicated, so in Indoor experimental research When conducting rock mechanics experiments, it is essential to consider the coupling effect of temperature and stress on rock mechanical properties. Using high and low temperature environmental chambers or high temperature furnaces can perform real-time or high-temperature rock mechanics experiments during indoor experiments. , which makes the experimental environment closer to the environment of deep rocks, and also makes the experimental research results more valuable for reference.

脆性材料的表面和内部含有大量的弱面、裂隙等缺陷,在工程中,由于外界应力环境的扰动,一系列的弱化结构发生了裂隙的萌生,扩展,联合甚至贯通,一般的室内试验系统在实验过程中只能测试到力-位移曲线,这些数据只能提供很有限的特征性质,也不能检测到在整个变形过程中的不均匀的裂隙的形成与演化。The surface and interior of brittle materials contain a large number of defects such as weak surfaces and cracks. In engineering, due to the disturbance of the external stress environment, a series of weakened structures have crack initiation, expansion, joint and even penetration. The general indoor test system in Only force-displacement curves can be tested during the experiment, and these data can only provide very limited characteristic properties, and cannot detect the formation and evolution of inhomogeneous cracks throughout the deformation process.

经典的实验力学包括应变电测方法和各种光测方法。以电阻应变计为敏感元件的应变电测技术因其尺寸小、重量轻、测量灵敏度高、测量应变量程大、频率响应高等优点而广泛应用于自动化监测控制、称重计量自动化、工程和科学实验中,但是它不适应于某些特殊环境(如高温)。后来发展起来的其他应变传感元件,如电容应变计等,可用于高温结构长期应变测量。应变电测法的不足:应变电测方法一般是单点或逐点测量,无法得到构件的全局应力应变分布,只能测量构件表面上的应变,而且是构件表面的平均应变,对于应力梯度很大或应力集中的构件表面测量误差较大,而且对测量环境要求较高,任何的风吹草动都会影响到测量结果。Classical experimental mechanics includes strain electrical measurement methods and various optical measurement methods. The strain electrical measurement technology with resistance strain gauge as the sensitive element is widely used in automatic monitoring and control, weighing and measurement automation, engineering and science because of its small size, light weight, high measurement sensitivity, large measurement strain range, and high frequency response. In the experiment, but it is not suitable for some special environments (such as high temperature). Other strain sensing elements developed later, such as capacitive strain gauges, can be used for long-term strain measurement of high-temperature structures. Insufficiency 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 measurement error on the surface of components with large gradient or concentrated stress is relatively large, and the requirements for the measurement environment are high, and any disturbance will affect the measurement results.

常用的光测方法如光弹性法、贴片光弹法、全息光弹法、全息干涉法、云纹干涉法、散斑干涉法等,这些传统的光测力学方法的数据采集是利用胶片或干板记录带有被测物体表面位移或变形信息的光强分布,通过显影定影得到照片。但是由于显影定影操作费时费力,实验条件难于精确控制,实验结果难于精确重复,不利于后续的利用计算机图像处理。Commonly used photometric methods such as photoelasticity, patch photoelasticity, holographic photoelasticity, holographic interferometry, moiré interferometry, speckle interferometry, etc. The data collection of these traditional photomechanical methods is to use film or The dry plate records the light intensity distribution with the surface displacement or deformation information of the measured object, and the photo is obtained by developing and fixing. However, due to the time-consuming and labor-intensive development and fixing operations, it is difficult to accurately control the experimental conditions, and it is difficult to accurately repeat the experimental results, which is not conducive to the subsequent use of computer image processing.

实用新型内容Utility model content

技术问题:本实用新型的目的是要提供一种全场测量精度高,实验结果准确的脆性材料高低温加载下力学特性及损伤变化测量系统。Technical problem: The purpose of this utility model is to provide a measurement system for measuring mechanical properties and damage changes of brittle materials under high and low temperature loading with high measurement accuracy and accurate experimental results.

技术方案:本实用新型的脆性材料高低温加载下力学特性及损伤变化测量系统,其特征是:测量系统包括:力学特性测试装置、温度应力耦合加载装置、声发射信号检测装置和影像采集装置;影像采集装置位于温度应力耦合加载装置的一侧,力学特性测试装置和声发射信号检测装置分别与温度应力耦合加载装置连接。Technical solution: The mechanical properties and damage change measurement system of brittle materials under high and low temperature loading of the utility model is characterized in that: the measurement system includes: mechanical property testing device, temperature stress coupling loading device, acoustic emission signal detection device and image acquisition device; The image acquisition device is located on one side of the temperature-stress coupling loading device, and the mechanical characteristic testing device and the acoustic emission signal detection device are respectively connected with the temperature-stress coupling loading device.

所述的力学特性测试装置包括一个全程数字控制的计算机系统,能够自动计算实验试件的应力、应变,能够控制高低温环境箱的温度,并能够安全方便的操控加载装置。The mechanical characteristic testing device includes a computer system with full digital control, which can automatically calculate the stress and strain of the experimental specimen, control the temperature of the high and low temperature environment box, and safely and conveniently control the loading device.

所述的温度应力耦合加载装置由具有透明壁的高低温环境箱与电液伺服的加载装置构成,加载装置能在环境箱工作的同时进行加载,实现温度场与应力场的耦合;环境箱具有方便采集影像的透明壁。The temperature-stress coupling loading device is composed of a high-low temperature environmental box with a transparent wall and an electro-hydraulic servo loading device. The loading device can be loaded while the environmental box is working to realize the coupling of the temperature field and the stress field; the environmental box has Transparent walls for easy image acquisition.

所述的声发射信号采集装置:用美国的PCI-2声发射采集装置采集材料试验过程中的声发射信号、并采用希尔伯特黄变换对声发射信号进行分析。The acoustic emission signal collection device: use the American PCI-2 acoustic emission collection device to collect the acoustic emission signals during the material test, and use the Hilbert-Huang transform to analyze the acoustic emission signals.

所述的影像采集装置:由高速摄像机与材料试件两侧的对称光源组成,并采用数字图像相关技术对采集到的影像进行位移场与应变场分析。The image acquisition device is composed of a high-speed camera and symmetrical light sources on both sides of the material specimen, and digital image correlation technology is used to analyze the displacement field and strain field of the collected images.

有益效果,由于采用了上述方案,能够测试在温度-应力耦合场中材料如岩石的力学特性,并在力学特性测试装置上加上了声发射信号检测装置与影像采集装置,数字图像相关技术能实现试件位移的全场测量,精度高,使得实验结果更加的准确;对声发射信号进行分析可以得到试件在温度-应力耦合效应下的损伤与衰减,从而数字图像相关技术与声发射系统结合的手段实现了从宏观与微观描述材料破裂的过程。相对于现有的测试系统优点在于:Beneficial effects, due to the adoption of the above scheme, the mechanical properties of materials such as rocks in the temperature-stress coupling field can be tested, and an acoustic emission signal detection device and an image acquisition device are added to the mechanical property testing device, and the digital image correlation technology can Realize the full-field measurement of specimen displacement with high precision, making the experimental results more accurate; analyzing the acoustic emission signal can obtain the damage and attenuation of the specimen under the temperature-stress coupling effect, so that digital image correlation technology and acoustic emission system The combination of means realizes the description of the material fracture process from the macroscopic and microscopic. Compared with the existing test system, the advantages are:

1.通过利用高低温环境箱可以在室内实验时进行实时或者高温后的脆性材料如岩石力学实验,这样使得实验环境更能接近实际环境,比如深部岩石所处的环境,也使得实验研究结果更具有参考价值。1. Through the use of high and low temperature environmental chambers, real-time or high-temperature brittle materials such as rock mechanics experiments can be carried out in indoor experiments, which makes the experimental environment closer to the actual environment, such as the environment of deep rocks, and makes the experimental research results more accurate. It has reference value.

2.采用数字图像相关技术得到试验过程中试件局部的位移场以及应变场,测量系统具有非接触、全场测量、应用广、精度高、对原始数据的采集方式简单、测量要求环境低、便于实现整个系统的自动化。2. Using digital image correlation technology to obtain the local displacement field and strain field of the test piece during the test, the measurement system has non-contact, full-field measurement, wide application, high precision, simple collection of original data, and low measurement requirements. It is convenient to realize the automation of the whole system.

3.利用声发射信号采集系统,通过测量压裂的能量释放来检测裂隙的形成和演化是一种可行的和有效的技术,声发射信号的后处理为解释非线性和非稳定的信号提供了一种有效的途径。3. Using the acoustic emission signal acquisition system, it is a feasible and effective technique to detect the formation and evolution of fractures by measuring the energy release of fracturing. The post-processing of acoustic emission signals provides a basis for interpreting nonlinear and unstable signals. an efficient way.

附图说明:Description of drawings:

图1为本实用新型的系统结构示意图。Fig. 1 is a schematic diagram of the system structure of the present utility model.

具体实施方式detailed description

下面结合附图对本实用新型的一个实施例作进一步的描述:An embodiment of the present utility model is further described below in conjunction with accompanying drawing:

本实用新型的脆性材料高低温加载下力学特性及损伤变化测量系统,包括:力学特性测试装置、温度应力耦合加载装置、声发射信号检测装置和影像采集装置;影像采集装置位于温度应力耦合加载装置的一侧,力学特性测试装置和声发射信号检测装置分别与温度应力耦合加载装置连接。The utility model relates to a measurement system for mechanical properties and damage changes of brittle materials under high and low temperature loading, including: a mechanical property testing device, a temperature-stress coupling loading device, an acoustic emission signal detection device, and an image acquisition device; the image acquisition device is located in the temperature-stress coupling loading device On one side, the mechanical characteristic test device and the acoustic emission signal detection device are respectively connected with the temperature stress coupling loading device.

所述的力学特性测试装置:一个高智能的计算机系统,能够自动计算实验试件的应力,应变,能够控制高低温环境箱的温度,能够安全方便的操控加载装置;与现有的力学特性测试装置相比更加智能化,操作更加简单,更加安全,更能够节省人力。The mechanical characteristic testing device: a highly intelligent computer system, which can automatically calculate the stress and strain of the experimental specimen, can control the temperature of the high and low temperature environment box, and can safely and conveniently control the loading device; it is compatible with the existing mechanical characteristic test Compared with the device, it is more intelligent, the operation is simpler, safer, and it can save manpower.

所述的温度应力耦合加载装置:由具有透明壁的高低温环境箱与电液伺服的加载装置构成,加载装置能在环境箱工作的同时进行加载,实现了温度场与应力场的耦合;环境箱具有透明壁,方便影像采集装置采集影像。The temperature-stress coupling loading device: it is composed of a high-low temperature environmental chamber with a transparent wall and an electro-hydraulic servo loading device. The loading device can perform loading while the environmental chamber is working, realizing the coupling of the temperature field and the stress field; the environment The box has a transparent wall, which is convenient for the image collection device to collect images.

所述的声发射信号采集装置:用美国的PCI-2声发射采集装置采集材料试验过程中的声发射信号并采用希尔伯特黄变换对声发射信号进行分析;与现有的声发射采集装置相比灵敏度更高,而且希尔伯特黄变换的后处理方法比现阶段的采用的小波变换或傅里叶变换方法分析更加准确,更加全面。The acoustic emission signal collection device: use the PCI-2 acoustic emission collection device in the United States to collect the acoustic emission signal in the material test process and use the Hilbert-Huang transform to analyze the acoustic emission signal; it is different from the existing acoustic emission collection Compared with the device, the sensitivity is higher, and the post-processing method of Hilbert Huang transform is more accurate and comprehensive than the wavelet transform or Fourier transform method used at the present stage.

所述的影像采集装置:由高速摄像机与材料试件两侧的对称光源组成,并采用数字图像相关技术对采集到的影像进行位移场与应变场分析,现阶段脆性材料实验力学采用应变电测方法和各种光测方法,与其相比,本实用新型采用的装置与方法精度更高,能用于全场测量,应用更广。The image acquisition device is composed of a high-speed camera and symmetrical light sources on both sides of the material specimen, and digital image correlation technology is used to analyze the displacement field and strain field of the collected images. At present, the experimental mechanics of brittle materials adopts strain electric Compared with the measurement method and various light measurement methods, the device and method adopted by the utility model have higher precision, can be used for full-field measurement, and have wider applications.

Claims (5)

1.一种脆性材料高低温加载下力学特性及损伤变化测量系统,其特征是:测量系统包括:力学特性测试装置、温度应力耦合加载装置、声发射信号检测装置和影像采集装置;影像采集装置位于温度应力耦合加载装置的一侧,力学特性测试装置和声发射信号检测装置分别与温度应力耦合加载装置连接。 1. A system for measuring mechanical properties and damage changes of brittle materials under high and low temperature loading, characterized in that: the measurement system includes: mechanical property testing device, temperature-stress coupling loading device, acoustic emission signal detection device and image acquisition device; image acquisition device Located on one side of the temperature-stress coupling loading device, the mechanical characteristic testing device and the acoustic emission signal detection device are respectively connected with the temperature-stress coupling loading device. 2.根据权利要求1所述的脆性材料高低温加载下力学特性及损伤变化测量系统,其特征是:所述的力学特性测试装置包括一个全程数字控制的计算机系统,能够自动计算实验试件的应力、应变,能够控制高低温环境箱的温度,并能够安全方便的操控加载装置。 2. The system for measuring mechanical properties and damage changes of brittle materials under high and low temperature loading according to claim 1 is characterized in that: said mechanical property testing device includes a computer system with full digital control, which can automatically calculate the Stress, strain, can control the temperature of the high and low temperature environment box, and can control the loading device safely and conveniently. 3.根据权利要求1所述的脆性材料高低温加载下力学特性及损伤变化测量系统,其特征是:所述的温度应力耦合加载装置由具有透明壁的高低温环境箱与电液伺服的加载装置构成,加载装置能在环境箱工作的同时进行加载,实现温度场与应力场的耦合;环境箱具有方便采集影像的透明壁。 3. The system for measuring mechanical properties and damage changes of brittle materials under high and low temperature loading according to claim 1, characterized in that: the temperature stress coupling loading device is composed of a high and low temperature environmental chamber with a transparent wall and an electro-hydraulic servo loading device. The device is composed of a loading device that can be loaded while the environmental chamber is working to realize the coupling of the temperature field and the stress field; the environmental chamber has a transparent wall that is convenient for image collection. 4.根据权利要求1所述的脆性材料高低温加载下力学特性及损伤变化测量系统,其特征是:所述的声发射信号采集装置:用美国的PCI-2声发射采集装置采集材料试验过程中的声发射信号、并采用希尔伯特黄变换对声发射信号进行分析。 4. The system for measuring mechanical properties and damage changes of brittle materials under high and low temperature loading according to claim 1, characterized in that: the acoustic emission signal collection device: use the PCI-2 acoustic emission collection device in the United States to collect the material test process The acoustic emission signal in the paper, and the acoustic emission signal is analyzed by Hilbert-Huang transform. 5.根据权利要求1所述的脆性材料高低温加载下力学特性及损伤变化测量系统,其特征是:所述的影像采集装置:由高速摄像机与材料试件两侧的对称光源组成,并采用数字图像相关技术对采集到的影像进行位移场与应变场分析。 5. The system for measuring mechanical properties and damage changes of brittle materials under high and low temperature loading according to claim 1, characterized in that: the image acquisition device is composed of a high-speed camera and symmetrical light sources on both sides of the material specimen, and adopts Digital image correlation technology analyzes the displacement field and strain field of the collected images.
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CN106092764A (en) * 2016-08-04 2016-11-09 清华大学 There is ultrasonic and acoustic emission detection function concrete temperature stress testing machine
CN108548726A (en) * 2018-05-21 2018-09-18 中国电建集团华东勘测设计研究院有限公司 Rock crack propagation test device under thermosetting coupling condition
CN108693042A (en) * 2018-05-03 2018-10-23 中国石油大学(北京) A kind of fracturing device of Simultaneous Monitoring crack extension and stress variation
CN111855818A (en) * 2020-08-26 2020-10-30 华北理工大学 Realistic three-axis acoustic emission field strain joint observation device

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106092764A (en) * 2016-08-04 2016-11-09 清华大学 There is ultrasonic and acoustic emission detection function concrete temperature stress testing machine
CN108693042A (en) * 2018-05-03 2018-10-23 中国石油大学(北京) A kind of fracturing device of Simultaneous Monitoring crack extension and stress variation
CN108548726A (en) * 2018-05-21 2018-09-18 中国电建集团华东勘测设计研究院有限公司 Rock crack propagation test device under thermosetting coupling condition
CN108548726B (en) * 2018-05-21 2024-05-10 中国电建集团华东勘测设计研究院有限公司 Rock crack growth testing device under thermosetting coupling condition
CN111855818A (en) * 2020-08-26 2020-10-30 华北理工大学 Realistic three-axis acoustic emission field strain joint observation device

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