CN113686967B - Methods to reduce the impact of boundary reflection effects on stress wave propagation test data - Google Patents
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Abstract
本发明涉及一种降低边界反射效应对应力波传播试验数据影响的方法。适用于应力波传播室内试验技术领域。本发明所采用的技术方案是：一种降低边界反射效应对应力波传播试验数据影响的方法，其特征在于：在试样和应力波传播试验的加载端之间设置边界材料，并在边界材料和加载端之间设置垫块；所述边界材料的波阻抗值为最优波阻抗Zb。通过本发明中最优波阻抗的计算公式计算得到应力波传播室内试验中边界材料(吸波材料)的最优波阻抗，从而根据此选择合适的边界材料用于应力波传播室内试验中，对反射波进行吸收，从而切实改善应力波传播室内试验中的边界反射效应，最大化地减弱应力波在边界处的边界反射效应。
The invention relates to a method for reducing the impact of boundary reflection effects on stress wave propagation test data. It is suitable for the technical field of indoor testing of stress wave propagation. The technical solution adopted by the present invention is: a method for reducing the impact of boundary reflection effects on stress wave propagation test data, which is characterized in that: a boundary material is set between the sample and the loading end of the stress wave propagation test, and the boundary material A cushion block is provided between the loading end and the boundary material; the wave impedance value of the boundary material is the optimal wave impedance Z b . The optimal wave impedance of the boundary material (absorbing material) in the indoor test of stress wave propagation is calculated through the calculation formula of the optimal wave impedance in the present invention, and the appropriate boundary material is selected based on this for the indoor test of stress wave propagation. The reflected waves are absorbed, thereby effectively improving the boundary reflection effect in the indoor test of stress wave propagation and maximizing the weakening of the boundary reflection effect of stress waves at the boundary.
Description
Technical Field
The invention relates to a method for reducing the influence of boundary reflection effect on stress wave propagation test data. The method is suitable for the technical field of stress wave propagation indoor tests.
Background
Deep engineered rock contains a large number of discrete structural surfaces, such as faults, joints, and fissures, that exist to cause rapid dissipation of stress wave energy. In addition, under the condition that a deep rock body is normally endowed with higher ground stress, the excavation unloading can cause disturbance on surrounding rock properties and a ground stress field, so that the physical and mechanical properties (porosity, permeability, joint rigidity and the like) of the rock and the joint are changed, and the propagation attenuation rule of stress waves in the joint rock body is influenced, so that the propagation attenuation mechanism of the stress waves in the deep engineering rock body is quite complex, and a plurality of influencing factors are influenced, and therefore, the propagation attenuation rule of the stress waves in the joint rock body is difficult to accurately analyze and predict in theory. The indoor test is taken as an effective means for researching the propagation attenuation rule of the stress wave, can be mutually verified with theoretical research results, and can also provide certain reference and reference for field engineering application.
In order to research the propagation attenuation rule of stress wave in the jointed rock mass, a plurality of students at home and abroad develop propagation tests of one-dimensional stress wave in the rock mass. When the stress wave reaches the boundary of the rock sample, the stress wave will be transreflective between different media. The part of reflected wave generated at the boundary is reflected back to the rock sample along the original path, and the superimposed interference is generated between the part of reflected wave and the original waveform within the duration of the stress wave, so that the acquired stress wave signal is difficult to truly reflect the propagation attenuation rule of the stress wave in the rock medium.
Disclosure of Invention
The invention aims to solve the technical problems that: in order to solve the above-described problems, a method for reducing the influence of the boundary reflection effect on stress wave propagation test data is provided.
The technical scheme adopted by the invention is as follows: a method of reducing the effect of boundary reflection on stress wave propagation test data, comprising:
setting boundary materials between the sample and the loading end of the stress wave propagation test, and setting cushion blocks between the boundary materials and the loading end;
the wave impedance value of the boundary material is the optimal wave impedance Z b ；
The optimal wave impedance Z b The following equation is used for calculation:
-Z b 5 +Z b 4 (7Z a -2Z c )+Z b 3 (Z a 2 -10Z a Z c -Z c 2 )+Z a Z b 2 (Z a 2 +10Z a Z c -Z c 2 )+Z a 2 Z b Z c (2Z a -7Z c )+Z a 3 Z c 2 ＝0
wherein Z is a Z is the wave impedance value of the sample c And the wave impedance value of the cushion block.
The thickness of the boundary material is 1/12-1/8 of the length of the sample.
The thickness of the border material is 1/10 of the length of the sample.
The thickness of the cushion block is 1/4-1/2 of the thickness of the boundary material.
The cushion block adopts a steel cushion block.
The cross-sectional areas of the pad, border material and sample are the same.
The beneficial effects of the invention are as follows: the optimal wave impedance of the boundary material (wave absorbing material) in the stress wave propagation indoor test is obtained through calculation according to the calculation formula of the optimal wave impedance, so that a proper boundary material is selected to be used in the stress wave propagation indoor test to absorb reflected waves, the boundary reflection effect in the stress wave propagation indoor test is practically improved, the boundary reflection effect of the stress wave at the boundary is reduced to the greatest extent, the influence of the boundary reflection effect on stress wave propagation test data is avoided, and the authenticity and the effectiveness of the test data are ensured.
Drawings
FIG. 1 is a schematic diagram of a stress wave propagation test apparatus in an embodiment.
FIG. 2 is a schematic diagram of a model of the transreflection of stress waves between three media in an embodiment.
FIG. 3 is V in the embodiment L /V I The ratio is a curve of the change of the wave impedance value of the wave absorbing material.
FIG. 4 is a graph showing the amplitude of stress wave as a function of propagation distance for rubber as a boundary material in the example.
Fig. 5 is a graph showing the amplitude of stress wave as a function of propagation distance for a steel block as a boundary material in the example.
Fig. 6 is a graph showing the amplitude of stress wave as a function of propagation distance for pine as a boundary material in the example.
1. A sandstone sample; 2. a border material; 3. a cushion block; 4. a sample and boundary material interface; 5. boundary material and pad interface; 6. a pendulum system; 7. an acceleration sensor; 8. a rigid frame; 9. loading an oil cylinder; 10. a hydraulic jack; 11. a data acquisition instrument; 12. a data transmission line.
Detailed Description
The present embodiment is a method of reducing the effect of boundary reflection on stress wave propagation test data by providing a boundary material between a sample and a loading end of a stress wave propagation test and providing a spacer between the boundary material and the loading end.
In this example, the boundary material adopts the wave impedance value closest to the optimal wave impedance Z b Is the optimum wave impedance Z b The following equation is used for calculation:
-Z b 5 +Z b 4 (7Z a -2Z c )+Z b 3 (Z a 2 -10Z a Z c -Z c 2 )+Z a Z b 2 (Z a 2 +10Z a Z c -Z c 2 )+Z a 2 Z b Z c (2Z a -7Z c )+Z a 3 Z c 2 ＝0(1)
wherein Z is a Z is the wave impedance value of the sample c Is the wave impedance value of the cushion block.
The thickness of the boundary material in this case is 1/12 to 1/8, preferably 1/10, of the sample length. The thickness of the pad in this embodiment is 1/4 to 1/2, preferably 1/4, of the thickness of the border material.
The data impact of whether the boundary reflection effect can be reduced in this embodiment is verified by a stress wave propagation test, taking an indoor propagation test of stress waves in a sandstone medium as an example:
step 1, as shown in fig. 1, a stress wave propagation test device mainly comprises a pendulum system, an acceleration sensor, a rigid frame, a loading end (a loading oil cylinder and a jack), a data acquisition instrument, a data transmission line and the like, wherein the length, width and height dimensions of a sandstone sample are respectively 1500mm multiplied by 120mm, and the sandstone sample is horizontally placed in the rigid frame; the loading oil cylinder and the hydraulic jack are positioned at the right end of the sandstone sample, and the axial load is applied to the sandstone sample through the counterforce provided by the rigid frame; placing a boundary material between the sandstone sample and the loading cylinder for improving the reflection effect of the stress wave at the boundary; because the cross section area of the loading cylinder is smaller than that of the boundary material, in order to avoid deformation damage caused by uneven stress of the boundary material due to axial loading, a cushion block (steel cushion block) is arranged between the loading cylinder and the boundary material, and the cushion block, the boundary material and the sandstone sample have the same cross section area.
And 2, knocking the sandstone sample by using a pendulum system at the left end to excite the stress wave, collecting stress wave signal amplitude values at different propagation distances by each acceleration sensor when the stress wave propagates in the sandstone sample, and evaluating the inhibition effect of different boundary materials on the boundary reflection effect by analyzing attenuation rules of the stress wave signal amplitude values at different propagation distances.
And step 3, simplifying a calculation model of the optimal wave impedance of the boundary material on the basis of the stress wave propagation indoor test, and only considering the transreflective effect of the stress wave among the sandstone sample, the boundary material and the cushion block. As shown in FIG. 2, a calculation model of the transreflection of stress wave in the three media is established, and the wave impedance value of the sandstone sample is Z a ＝6.96×10 6 kg/m 2 S, wave impedance value of boundary material Z b The wave impedance value of the steel cushion block is Z c ＝41.08×10 6 kg/m 2 ·s。
Step 4, when the excited stress wave propagates from the sandstone sample to the boundary material, a first transreflective phenomenon occurs at the interface between the sample and the boundary material, and reflected waves V are generated respectively R1 And transmitted wave V T1 The expression is shown in the following formula 2, wherein the reflected wave V R1 Returns along the original path into the sandstone sample, and transmits wave V T1 Into the boundary material.
Wherein: v (V) I Is the initial incident wave.
Step 5, when transmitting wave V T1 When the boundary material is continuously transmitted to the cushion block, the second transreflective phenomenon occurs at the interface of the boundary material and the cushion block, and reflected waves V are respectively generated R2 And transmitted wave V T2 The expression is shown in the following formula 3, wherein the reflected wave V R2 Returns along the original path into the boundary material, transmitting wave V T2 Into the spacer.
Step 6, since only the transreflective effect of the stress wave between the sandstone sample, the boundary material and the pad is considered, only the return into the boundary materialReflected wave V in (a) R2 Analysis was performed. When reflected wave V R2 When the boundary material is continuously transmitted to the sandstone sample, the third transreflective phenomenon occurs at the interface of the sample and the boundary material, and reflected waves V are respectively generated R3 And transmitted wave V T3 The expression is shown in formula 4, wherein the reflected wave V R3 Returns along the original path into the boundary material, transmitting wave V T3 Into the sandstone sample.
Step 7, and so on, reflected wave V R3 Continuously generating multiple times of transreflective between the interface of the sample and the boundary material and the interface of the boundary material and the cushion block, and repeatedly adopting the methods of the step 5 and the step 6 to obtain V T5 、V T7 Etc.
The sum of all left-going stress waves reflected back into the sandstone sample is denoted as V L Which comprises V R1 、V T3 、V T5 …. As the number of transflectors increases, the amplitude of the left-hand stress wave reflected back into the rock sample will gradually decrease. Therefore, to simplify the calculation, only V is taken L The first three terms in the expression are calculated, the subsequent left traveling wave is negligible in size, and then V L The expression of (2) is shown in the formula 5;
V L ＝V R1 +V T3 +V T5 (5)
step 8, V is R1 、V T3 、V T5 The calculation formula of (2) is introduced into formula 4, V L The expression of (2) is shown in formula 6.
Wherein the wave impedance value Z of the sandstone sample a ＝6.96×10 6 kg/m 2 S, the wave impedance value of the pad is Z c ＝41.08×10 6 kg/m 2 S, can give V L /V I Ratio and boundary materialWave impedance (Z) b ) The change curve of (2) is shown in FIG. 3.
As can be seen from FIG. 3, the wave impedance value Z increases from point O to point A b Increasing from 0 to 1.12X10 6 kg/m 2 ·s，V L /V I The ratio curve of (2) shows a steep decline trend; when the wave impedance value Z b ＝1.12×10 6 kg/m 2 When s, the amplitude of the left traveling wave is zero, and theoretically, the point A in the figure 3 represents the optimal wave impedance value of the boundary material under the working condition; increasing from point A to point B, the wave impedance value Z b From 1.12X10 6 kg/m 2 S is increased to 6.82×10 6 kg/m 2 ·s，V L /V I The ratio of (2) increases from zero to-0.71, i.e. the left travelling wave amplitude increases gradually; after point B, along with the wave impedance value Z b Continue to increase, V L /V I The ratio of (2) gradually tends to stabilize.
In conclusion, when V L /V I When the ratio of the wave impedance value is zero, the amplitude of the left stress wave in all reflected sand rock samples is minimum, and the corresponding wave impedance value is the optimal wave impedance value Z of the boundary material b ＝1.12×10 6 kg/m 2 S. When V is L /V I When the ratio of (2) is zero, equation 6 may be modified to equation 1.
Step 9, calculating by adopting the method 1 based on the calculation model of the optimal wave impedance of the boundary material to obtain the optimal wave impedance value of the boundary material under the test working condition of 1.12 multiplied by 10 6 kg/m 2 ·s。
And respectively carrying out a plurality of stress wave propagation indoor tests by replacing boundary materials with different wave impedance values, so as to verify the optimal wave impedance calculation method according to the embodiment. Three mediums with different wave impedance values are mainly selected as boundary materials, the medium a is rubber, and the wave impedance value is 0.35 multiplied by 10 6 kg/m 2 S; the medium b is a steel block, and the wave impedance value is 41.08 multiplied by 10 6 kg/m 2 S; the medium c is pine wood with a wave impedance value of 1.89 multiplied by 10 6 kg/m 2 S (closest).
And 10, respectively taking the three media as boundary materials, and exciting stress wave signals by using pendulum bob strike under each working condition. In order to obtain stable waveform signals, five repeated strokes are performed under each working condition. Stress wave signal amplitude data at different propagation distances are collected through acceleration sensors uniformly distributed on the sandstone sample, and the inhibition effect of boundary reflection effect is analyzed when three mediums are used as boundary materials. Fig. 4, 5 and 6 are graphs showing the amplitude of stress wave signal as a function of propagation distance, respectively, for rubber, steel blocks and pine as boundary materials.
Step 11, according to V in FIG. 3 L /V I The ratio is along with the change curve of the boundary material wave impedance value, when rubber and steel blocks are used as boundary materials, the left reflected wave generated is 0.75 times and 0.7 times of the incident wave respectively, and as the propagation distance increases, the amplitude of signals received by two sensors which are closer to the boundary of a rock sample is increased, which is shown in fig. 4 and 5, because the reflected wave generated by stress waves at the end part of the rock sample and the original waveform generate superposition amplification effect, the inhibition effect of the rubber and the steel blocks on the boundary reflection effect is poor.
When pine is used as the boundary material, the left reflected wave is 0.21 times of the incident wave, and as shown in fig. 6, the stress wave signal amplitude is gradually reduced along with the increase of the propagation distance, and no abnormal increase phenomenon occurs, which means that when pine is used as the boundary wave absorbing material, the intensity of the reflected wave at the boundary can be obviously reduced, and the effect of inhibiting the boundary reflection effect is better.
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Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60355A (en) * | 1984-05-30 | 1985-01-05 | Hitachi Ltd | Ultrasonic microscope |
| JP2001124743A (en) * | 1999-10-25 | 2001-05-11 | Hitachi Ltd | Ultrasonic inspection method and apparatus for thin plate joints |
| JP2001289625A (en) * | 2000-04-07 | 2001-10-19 | Nissan Motor Co Ltd | Contact type ultrasonic sensor with delay material |
| JP2007187631A (en) * | 2006-01-16 | 2007-07-26 | Non-Destructive Inspection Co Ltd | Method and apparatus for detecting position of boundary surface |
| CN106406141A (en) * | 2016-10-10 | 2017-02-15 | 中国电建集团华东勘测设计研究院有限公司 | Model test system and method for seabed seismic wave detection |
| CN108956670A (en) * | 2018-07-13 | 2018-12-07 | 北京工业大学 | Prepare the method for modifying with high cohesive force polyvinyl chloride surface |
| CN109029177A (en) * | 2018-08-30 | 2018-12-18 | 西北矿冶研究院 | Blasting method for access type stoping |
| CN109991159A (en) * | 2019-04-25 | 2019-07-09 | 中国电建集团华东勘测设计研究院有限公司 | A kind of earth rock cofferdam bed course and geomembrane interfacial friction factor device for quick testing and method |
| WO2019205189A1 (en) * | 2018-04-23 | 2019-10-31 | 东北大学 | Test apparatus and method for key roof block collapse in bidirectional static-dynamic loading |
| CN110873546A (en) * | 2019-11-28 | 2020-03-10 | 中国水利水电第七工程局有限公司 | Construction base surface pioneer groove excavation method based on explosive energy regulation |
| CN211060752U (en) * | 2019-11-18 | 2020-07-21 | 中国水利电力对外有限公司 | A kind of energy dissipating device for blasting hole bottom |
| CN111665153A (en) * | 2019-11-20 | 2020-09-15 | 西北工业大学 | Medium strain rate compression experiment device and method |
| CN112557499A (en) * | 2020-06-30 | 2021-03-26 | 东南大学 | Experimental method for influence of joints on stress wave transmission and reflection rules based on ultrasonic waves |
| CN112986012A (en) * | 2021-02-09 | 2021-06-18 | 北京工业大学 | Experimental device for research stress wave propagation characteristic in rock mass under high temperature |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8270251B2 (en) * | 2005-12-05 | 2012-09-18 | Xact Downhole Telemetry Inc. | Acoustic isolator |
| US9594057B2 (en) * | 2014-01-21 | 2017-03-14 | Baker Hughes Incorporated | Reflection-only sensor for fluid acoustic impedance, sound speed, and density |
| US11719090B2 (en) * | 2019-03-22 | 2023-08-08 | Baker Hughes Oilfield Operations Llc | Enhanced cement bond and micro-annulus detection and analysis |
-
2021
- 2021-09-03 CN CN202111031770.9A patent/CN113686967B/en active Active
Patent Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60355A (en) * | 1984-05-30 | 1985-01-05 | Hitachi Ltd | Ultrasonic microscope |
| JP2001124743A (en) * | 1999-10-25 | 2001-05-11 | Hitachi Ltd | Ultrasonic inspection method and apparatus for thin plate joints |
| JP2001289625A (en) * | 2000-04-07 | 2001-10-19 | Nissan Motor Co Ltd | Contact type ultrasonic sensor with delay material |
| JP2007187631A (en) * | 2006-01-16 | 2007-07-26 | Non-Destructive Inspection Co Ltd | Method and apparatus for detecting position of boundary surface |
| CN106406141A (en) * | 2016-10-10 | 2017-02-15 | 中国电建集团华东勘测设计研究院有限公司 | Model test system and method for seabed seismic wave detection |
| WO2019205189A1 (en) * | 2018-04-23 | 2019-10-31 | 东北大学 | Test apparatus and method for key roof block collapse in bidirectional static-dynamic loading |
| CN108956670A (en) * | 2018-07-13 | 2018-12-07 | 北京工业大学 | Prepare the method for modifying with high cohesive force polyvinyl chloride surface |
| CN109029177A (en) * | 2018-08-30 | 2018-12-18 | 西北矿冶研究院 | Blasting method for access type stoping |
| CN109991159A (en) * | 2019-04-25 | 2019-07-09 | 中国电建集团华东勘测设计研究院有限公司 | A kind of earth rock cofferdam bed course and geomembrane interfacial friction factor device for quick testing and method |
| CN211060752U (en) * | 2019-11-18 | 2020-07-21 | 中国水利电力对外有限公司 | A kind of energy dissipating device for blasting hole bottom |
| CN111665153A (en) * | 2019-11-20 | 2020-09-15 | 西北工业大学 | Medium strain rate compression experiment device and method |
| CN110873546A (en) * | 2019-11-28 | 2020-03-10 | 中国水利水电第七工程局有限公司 | Construction base surface pioneer groove excavation method based on explosive energy regulation |
| CN112557499A (en) * | 2020-06-30 | 2021-03-26 | 东南大学 | Experimental method for influence of joints on stress wave transmission and reflection rules based on ultrasonic waves |
| CN112986012A (en) * | 2021-02-09 | 2021-06-18 | 北京工业大学 | Experimental device for research stress wave propagation characteristic in rock mass under high temperature |
Non-Patent Citations (3)
| Title |
|---|
| DDA 方法中的两种无反射边界研究;甯尤军等;《工程力学》;第27卷(第4期);第19-23页 * |
| 反射应力波曲线特征与桩身缺陷浅析;石庆凡等;《公路交通技术》(第1期);第65-68页 * |
| 桩身参数与边界条件对低应变反射波影响研究;张志强;《硕士电子期刊》;第2-4章 * |
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