Method and equipment for testing explosion stress waves in large-depth rock soil

Abstract

The invention provides a testing method and testing equipment for explosion stress waves in large-depth rock soil, relates to the technical field of explosion stress measurement, and solves the technical problem that the testing accuracy of the explosion stress waves in the large-depth rock soil is poor. The test method comprises the following steps: providing a stress wave generator, a first tool and a second tool; a center hole and two measuring holes with the same hole depth are drilled in the rock soil, and the distances between the two measuring holes and the center hole are the same; a stress wave generator is placed in the center hole, and a first tool and a second tool are placed in the two measuring holes respectively; the first sensing surface and the edge, deviating from the second steel pipe, of the flow guide part are arranged opposite to the stress wave generator; collecting a first stress value of the first sensor and a second stress value of the second sensor; when the ratio of the first stress value to the second stress value is 1-1 / mu, storing the first stress value; otherwise, rejecting the first stress value; wherein mu is the Poisson's ratio of rock soil. The test method is high in measurement accuracy.

Description

Technical Field

[0001] The invention relates to the technical field of explosion stress measurement, and in particular to a method and equipment for testing explosion stress waves in deep rock and soil. Background Art

[0002] In order to measure the explosion stress wave in rock and soil, in the related technology, a long cylindrical barrel model is usually used to fill the rock and soil to be tested to simulate the underground rock and soil environment. The diameter and barrel height of the model generally do not exceed 10m, and the test range of the stress wave is limited.

[0003] For the field explosion stress test in rock and soil, although the test range can be expanded, the range of rock and soil that needs to be backfilled after the sensor is buried is also increased accordingly, and the workload of backfilling layer by layer is huge, and the experimental efficiency is low. On the other hand, when the sensor is directly buried in the rock and soil, adding soil and compacting the soil during backfilling can easily cause the sensor to move or the sensitive surface to change direction, resulting in poor accuracy of the explosion stress wave measured by the sensor. Summary of the invention

[0004] The purpose of the present invention is to provide a method and equipment for testing explosion stress waves in deep rock and soil, so as to solve the technical problem of poor accuracy in testing explosion stress waves in deep rock and soil.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] In a first aspect, the present invention provides a method for testing explosion stress waves in deep rock and soil, comprising:

[0007] A stress wave generator, a first tool and a second tool are provided; wherein the first tool comprises a first sensor, a first steel pipe and a first plate arranged at the bottom end of the first steel pipe, and a first surface of the first plate has a first opening for exposing a first sensing surface of the first sensor;

[0008] The second tooling includes a second steel pipe and a second plate vertically arranged at the bottom end of the second steel pipe, the second plate having two second surfaces distributed along a first direction, the axial direction of the second steel pipe being perpendicular to the first direction, and one of the second surfaces having a second opening for exposing a second sensing surface of the second sensor; the second plate having a guide portion surrounding the second sensing surface, the guide portion gradually becoming thinner in a direction away from the second sensing surface;

[0009] Drilling a central hole and two measuring holes with the same hole depth in the rock soil, wherein the two measuring holes are at the same distance from the central hole;

[0010] The stress wave generator is placed in the central hole, and the first tooling and the second tooling are placed in the two measuring holes respectively; wherein the first sensing surface and the edge of the guide portion away from the second steel pipe are both arranged opposite to the stress wave generator;

[0011] Collect a first stress value of the first sensor and a second stress value of the second sensor; when the ratio of the first stress value to the second stress value is 1 to 1 / μ, store the first stress value; otherwise, discard the first stress value; wherein μ is the Poisson's ratio of the rock and soil.

[0012] According to at least one embodiment of the present invention, the stress wave generator is placed in the central hole, and the first tooling and the second tooling are placed in the two measuring holes respectively, including:

[0013] Lead the wire of the first sensor through the first steel pipe to the ground, and lead the wire of the second sensor through the second steel pipe to the ground; wherein part of the first steel pipe is located above the ground, and part of the second steel pipe is located above the ground.

[0014] According to at least one embodiment of the present invention, when a center hole and two measuring holes having the same hole depth are drilled in the rock soil, the method includes:

[0015] Two measuring holes are drilled, and the two measuring holes and the center hole are on the same straight line.

[0016] According to at least one embodiment of the present invention, when the stress wave generator is placed in the central hole, and the first tooling and the second tooling are placed in the two measuring holes respectively, the method comprises:

[0017] The first steel pipe and the second steel pipe are adjusted so that the center point of the first sensing surface of the first sensor, the center point of the second sensing surface of the second sensor, and the center point of the stress wave generator are located on the same horizontal plane.

[0018] According to at least one embodiment of the present invention, after the stress wave generator is placed in the central hole and the first tooling and the second tooling are respectively placed in the two measuring holes, the testing method further includes:

[0019] The rock and soil are backfilled and compacted in the central hole and the two measuring holes.

[0020] According to at least one embodiment of the present invention, after backfilling and compacting the rock and soil in the center hole and the two measuring holes, the testing method further includes:

[0021] The stress wave generator is started to generate a stress wave that propagates spherically.

[0022] According to at least one embodiment of the present invention, the first tool further includes a transverse tube, the two ends of which are respectively vertically connected to the bottom end of the first steel tube and the top end of the first plate, and the first opening is close to the bottom end of the first plate; the testing method further includes:

[0023] Lead the wire of the first sensor through the transverse pipe and the first steel pipe to the ground.

[0024] According to at least one embodiment of the present invention, the first steel pipe includes a plurality of first pipe sections, the second steel pipe includes a plurality of second pipe sections, and the testing method further includes:

[0025] The first steel pipe is formed by screwing a plurality of the first pipe segments together, and the second steel pipe is formed by screwing a plurality of the second pipe segments together.

[0026] According to at least one embodiment of the present invention, the first tool further includes a first rubber tube, the second tool further includes a second rubber tube, and the testing method further includes:

[0027] Pass the wire of the first sensor through the first rubber tube, and fix the first rubber tube at the central axis of the first steel tube;

[0028] The wire of the second sensor is passed through the second rubber tube, and the second rubber tube is fixed at the central axis of the second steel tube.

[0029] In a second aspect, the present invention further provides a testing device for explosion stress waves in rock and soil at great depths, wherein the testing device executes the testing method described in the first aspect.

[0030] Among the one or more technical solutions provided in the exemplary embodiments of the present invention, at least one of the following beneficial effects can be achieved.

[0031] The test method of explosion stress waves in deep rock and soil provided by the exemplary embodiment of the present invention is to drill a hole downward in the rock and soil using a deep hole drill bit, and respectively open a center hole and two measuring holes with the same hole depth, wherein the two measuring holes are at the same horizontal distance from the center hole. The bottom of the center hole is used to place a stress wave generator, such as a blasting device, etc.; the bottoms of the two measuring holes are respectively placed with a first sensor in the first tooling and a second sensor in the second tooling to measure the stress waves at the two positions respectively. Specifically, the first sensing surface of the first sensor is arranged opposite to the stress wave generator, and the positive stress (first stress value) of the explosion stress wave can be measured; and the lateral side (the edge of the guide part away from the second steel pipe) of the second sensing surface of the second sensor is arranged opposite to the stress wave generator, and the lateral stress (second stress value) of the explosion stress wave can be measured.

[0032] Since the stress wave generator generates a spherical propagation stress wave, the values ​​of the stress waves at the same distance in space are the same, that is, the stress waves measured by the first sensor and the second sensor are the same; further, at the same position in the rock and soil, the ratio of the first stress value (normal stress) to the second stress value (lateral stress) has a certain proportional relationship. When the ratio is between 1 and 1 / μ, μ is the Poisson's ratio of the rock and soil, indicating that the first stress value measured by the first sensor is accurate, and when the ratio is outside the range of 1 to 1 / μ, it indicates that the first stress value measured by the first sensor is inaccurate. Therefore, the above proportional relationship can be used to determine whether the first sensor is aligned with the stress wave generator, thereby determining whether the first stress value measured by the first sensor is true and reliable.

[0033] Compared with the existing technology, the drilling method is not limited by depth, and the explosion stress wave test can be carried out at a hole depth of tens to hundreds of meters, which expands the test range of stress waves. At the same time, the workload of backfilling rock and soil in the drilling hole is also reduced, which improves the experimental efficiency.

[0034] Furthermore, the two pressure sensors of the exemplary embodiment of the present invention are fixed on the steel pipe, and their wires extend out of the ground through the steel pipe, so that they are not easily moved or the direction of the sensing surface is changed during backfilling of rock and soil, thereby making the test structure accurate.

[0035] Furthermore, a guide portion is provided around part of the circumference of the second sensing surface of the second sensor. The guide portion is roughly fan-shaped, thick in the middle and thin at the edges, that is, along the direction of propagation of the explosion stress wave. The guide portion can guide the stress wave to the second sensing surface and minimize the influence of the shape of the second plate itself on the stress wave as much as possible, so that the second stress value measured by the second sensor can be closer to the actual stress. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings illustrate exemplary embodiments of the present invention and together with the description serve to explain the principles of the present invention, and these drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification;

[0037] Figure 1 is an isometric structural schematic diagram of a first tooling according to an embodiment of the present invention;

[0038] Figure 2 is a schematic diagram of the main structure of a first tool according to an embodiment of the present invention;

[0039] Figure 3 is an isometric structural schematic diagram of a second tooling according to an embodiment of the present invention;

[0040] Figure 4 is a schematic diagram of the main structure of a second tool according to an embodiment of the present invention;

[0041] Figure 5 is a schematic diagram of a second plate and an explosion stress wave according to an embodiment of the present invention;

[0042] Fig. 6A is a stress of a first sensor test according to an embodiment of the present invention;

[0043] Figure 6B is a stress of a second sensor test according to an embodiment of the present invention;

[0044] Figure 7 β is a peak stress fitting curve of the first sensor and the second sensor according to an embodiment of the present invention.

[0045] Reference numerals: 11, first plate; 111, first surface; 12, first steel pipe; 13, transverse pipe; 14, first sensing surface; 21, second plate; 211, flow guide; 22, second steel pipe; 24, second sensing surface. DETAILED DESCRIPTION

[0046] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0047] In the related technology, the model test method is often used to test the stress wave pressure in underground rock and soil, and the pressure sensor is directly buried for measurement. The main problems include: most of the barrel-shaped models are filled with the rock and soil to be tested to simulate the underground rock and soil environment. The cylindrical model structure is generally not more than 10m, which limits the test range of stress waves; and the direct burial of pressure sensors requires large-scale excavation, which is a lot of work, and it is unprotected. The hard rock and soil in the medium can easily damage the sensor wires, and the pressure sensor is easy to deviate from the original measurement point during the burial process, and the accuracy of stress wave testing cannot be guaranteed.

[0048] In response to the above problems, an exemplary embodiment of the present invention provides a method for testing explosion stress waves in deep rock and soil, which adopts a drilling method and a method of encapsulating and fixing two sensors using tooling for burying. At the same time, two different toolings are used to respectively measure the lateral stress and normal stress of the explosion stress wave, and the lateral stress is used to verify whether the measurement result of the normal stress is correct.

[0049] The method for testing explosion stress waves in deep rock and soil according to an exemplary embodiment of the present invention includes:

[0050] Step S100: providing a stress wave generator, a first tool and a second tool.

[0051] The stress wave generator can generate spherical propagation stress waves, for example, for small or large equivalent charges, for example, thousands of kilograms of charges. The test method can be applied to large buried depth and large equivalent charges, and the buried depth and test range can reach tens of meters.

[0052] Figure 1 is an isometric structural schematic diagram of a first tooling according to an embodiment of the present invention; Figure 2 1 is a schematic diagram of the main structure of the first tool according to an embodiment of the present invention. Figure 1 and Figure 2 As shown, the first tooling includes a first sensor, a first steel pipe 12 and a first plate 11 arranged at the bottom end of the first steel pipe 12, and a first surface 111 of the first plate 11 has a first opening for exposing the first sensing surface 14 of the first sensor.

[0053] In practical applications, the first sensor is encapsulated in the first plate 11, and its first sensing surface 14 is exposed through a first opening provided in the first surface 111 of the first plate 11, so as to receive and sense stress waves. Exemplarily, the first sensor may be a pressure sensor, optionally a quartz sensor, which has stable sensitivity. The wire of the first sensor may extend from the ground through the first steel pipe 12 to be connected to a data acquisition device. The first steel pipe 12 may drive the first plate 11 to extend into the corresponding borehole, so as to bury the first sensor in the borehole in a predetermined orientation, and may also protect the wire of the first sensor to prevent hard rock and soil from damaging the wire of the first sensor, resulting in damage to the insulation layer, excessive signal noise, or even cutting off the wire of the first sensor and failing to detect a signal.

[0054] Exemplarily, the top of the first plate 11 is arranged at the bottom of the first steel pipe 12, the first opening is located at a position close to the bottom of the first surface 111 of the first plate 11, and the first opening is consistent in shape and size with the first sensing surface 14 of the first sensor, for example, it can be circular. The first sensing surface 14 is located below the first steel pipe 12 and away from the first steel pipe 12, which can reduce the reflection of the stress wave by the first steel pipe 12 and affect the accuracy of the first sensor in acquiring data.

[0055] In one example, the first tooling further includes a transverse tube 13 , both ends of which are vertically connected to the bottom end of the first steel tube 12 and the top end of the first plate 11 , respectively, and the first opening is close to the bottom end of the first plate 11 .

[0056] like Figure 1 As shown, the transverse tube 13 and the first plate 11 are arranged in an L shape, and the transverse tube 13 and the first steel tube 12 are also arranged in an L shape. The transverse tube 13 can be regarded as a cantilever so that the first steel tube 12 and the first sensor are separated by a certain distance in the horizontal direction, and the first sensing surface 14 of the first sensor is close to the bottom end of the first plate 11, that is, there is a certain distance between the first sensing surface 14 and the first steel tube 12 in both the vertical and horizontal directions. The reflection of the stress wave by the first steel tube 12 minimizes the interference to the data of the first sensor.

[0057] When the cross pipe 13 is connected to the first steel pipe 12, the wire of the first sensor can pass through the two and then reach the ground.

[0058] Exemplarily, the bottom end of the first steel tube 12 can be closed or open without affecting the protection of the wires therein.

[0059] In one example, the first plate 11 is made of a material that matches the wave impedance of rock and soil, such as nylon, PVC plastic, etc., which can reduce the impact on the first sensor, thereby reducing experimental errors and more accurately measuring the forward pressure of the explosion.

[0060] Figure 3 is an isometric structural schematic diagram of a second tooling according to an embodiment of the present invention; Figure 4 2 is a schematic diagram of the main structure of the second tool according to an embodiment of the present invention. Figure 3 and Figure 4 As shown, the second tooling provided by the exemplary embodiment of the present invention includes a second steel tube 22 and a second plate 21 vertically arranged at the bottom end of the second steel tube 22, the second plate 21 has two second surfaces distributed along the first direction, the axial direction of the second steel tube 22 is perpendicular to the first direction, and one second surface has a second opening for exposing the second sensing surface 24 of the second sensor; the second plate 21 has a guide portion 211 surrounding the second sensing surface 24, and the thickness of the guide portion 211 gradually becomes thinner along the direction away from the second sensing surface 24.

[0061] The second plate 21 and the second steel tube 22 are arranged in an L shape, and the axial direction of the second steel tube 22 can be perpendicular to the second surface, that is, the first direction is the vertical direction. Figure 3 As shown, the axial direction of the second steel pipe 22 may also be parallel to the second surface, that is, the first direction is a horizontal direction.

[0062] A second opening is provided on one of the two opposite second surfaces of the second plate 21 to expose the second sensing surface 24 of the second sensor packaged in the second plate 21 , and the wire of the second sensor can extend out of the ground through the second steel pipe 22 .

[0063] The second opening is arranged at a position of the second plate 21 far away from the second steel pipe 22 , which can minimize the influence of the stress wave reflected by the second steel pipe 22 on the stress measurement accuracy of the second sensor.

[0064] A guide portion 211 is formed at one end of the second plate 21 away from the second steel pipe 22. The guide portion 211 is a pancake-shaped structure that is thick in the middle and thin at the edges, and surrounds part of the circumference of the second opening. When it is fixed in the drilled hole, the edge of the guide portion 211 is facing the stress wave generator. Since its edge is sharp and gradually thickens in the middle, the stress wave can propagate unimpeded to the second opening, that is, the second sensing surface 24 of the second sensor, so that the influence of the shape of the second plate 21 itself on the stress wave is minimized, thereby improving the measurement accuracy of the second sensor.

[0065] In one example, the material of the second plate 21 is the same as that of the first plate 11 , the shape and size of the second opening is the same as that of the first opening, and the shape and thickness of the second steel pipe 22 are the same as that of the first steel pipe 12 , which are not described in detail here.

[0066] The first sensing surface 14 of the first sensor can face the stress wave generator directly, and can measure the normal stress of the stress wave; the second sensing surface 24 of the second sensor can face the stress wave generator laterally, and can measure the lateral stress of the stress wave. Figure 5 As shown, Figure 5 Schematic diagram of the second plate 21 and the explosion stress wave according to the embodiment of the present invention.

[0067] Under the action of blast stress wave, there is a certain relationship between normal stress and lateral stress in rock and soil, as described below:

[0068] A. Rock and soil present elastic stress state under the action of explosion stress.

[0069] Under the elastic state, the rock and soil present a triaxial stress state due to the explosion stress. The explosion stress σ at a point in the rock and soil is r It can be divided into three normal stress components and six shear stress components. The nine components are arranged according to certain rules, as shown in Formula 1.

[0070]

[0071] When the explosion stress is transmitted to the second sensor, Figure 5 As shown, since the second sensing surface 24 of the second sensor is placed perpendicular to the explosion center, the three-dimensional stress only has positive stress on each surface element, and the shear stress is equal to 0. Formula 1 can be rewritten as Formula 2:

[0072]

[0073] The stress data recorded by the second sensor is σ perpendicular to the second sensing surface 24. zz The time course curve.

[0074] It should be noted that the stress waves tested by the first sensor and the second sensor are generated by the same stress wave generator, that is, the normal stress obtained by the first sensor is the explosion stress σ r Therefore, in the actual test process, the lateral stress σ 侧 will always be less than the normal stress σ 正 , both satisfy equation 3.

[0075] σ zz =σ 侧 =σ r μ = σ 正 ·μ, formula 3;

[0076] Where μ is the Poisson's ratio of rock and soil.

[0077] Thus, the ratio of normal stress to lateral stress can be obtained, which satisfies equation 4.

[0078]

[0079] B. Rock and soil are in a fluid state under the action of explosion stress.

[0080] Formula 1 can be rewritten as Formula 5,

[0081]

[0082] σ m is the stress in each direction, and the magnitudes in the three directions are equal. In the fluid state, the stress recorded by the first sensor and the second sensor are both volume stresses, so we get formula 6:

[0083]

[0084] Thus, the ratio of normal stress to lateral stress can be obtained, satisfying Equation 7.

[0085]

[0086] In the rock and soil explosion test, the rock and soil medium in the vicinity of the explosive is in a fluid state, and the rock and soil medium in the far area is in an elastic state. From the above, we can get formula 8:

[0087]

[0088] In the rock and soil explosion test, the normal stress and the lateral stress obtained by the first sensor and the second sensor have a ratio between [1,1 / μ], where μ can give an accurate value of the Poisson's ratio through on-site rock and soil survey.

[0089] Step S200: drilling a center hole and two measuring holes with the same hole depth in rock soil, wherein the two measuring holes are at the same distance from the center hole.

[0090] In one example, a typical flat terrain is selected in the test field, and a measuring hole is drilled from the ground downward using a deep hole drill, the diameter of which can ensure that the first tooling and the second tooling can be accommodated. The distance between the measuring hole and the center hole is the same, so that the measured first stress value and the second stress value can be stress waves of the same intensity generated by the explosion center, and then it can be determined whether the first stress value is accurate.

[0091] In practical applications, the depths of the two measuring holes may be slightly greater than the depth of the central hole, so that there is room for adjustment of the positions of the first sensing surface and the second sensing surface.

[0092] Step S300: placing the stress wave generator in the central hole, and placing the first fixture and the second fixture in the two measuring holes respectively; wherein the first sensing surface 14 and the edge of the guide portion 211 away from the second steel pipe 22 are both arranged opposite to the stress wave generator.

[0093] The first sensor and the second sensor can be placed at the bottom of the measuring hole respectively through the first steel pipe 12 and the second steel pipe 22. Specifically, the first steel pipe and the second steel pipe are adjusted so that the first sensing surface 14 of the first sensor faces the explosion center, and the second sensing surface 24 of the second sensor faces the explosion center, that is, the sharp edge of the guide part 211 away from the second steel pipe 22 faces the explosion center.

[0094] Exemplarily, the first steel pipe 12 and the second steel pipe 22 are adjusted so that the center point of the first sensing surface 14 of the first sensor, the center point of the second sensing surface 24 of the second sensor and the center point of the stress wave generator are located on the same horizontal plane.

[0095] The measuring hole is then backfilled with the in-situ soil. During this process, the soil pit is compacted several times with a long stick so that the rock and soil density after backfilling is similar to that before drilling.

[0096] From the above, it can be seen that the depth of burying the stress wave generator by drilling is not limited. Even the stress wave generated by a large-yield explosion can eliminate the influence of ground reflection on the test results, reduce the error of the experiment, and obtain a more accurate explosion stress size. The depth of the center hole can be set to exceed the critical no-effect burial depth.

[0097] Compared with excavating tunnels for burial, the testing method of the exemplary embodiment of the present invention not only saves a lot of backfilling work, but also can be applied to the accurate measurement of stress waves generated by large-yield explosions.

[0098] In one example, the first steel pipe 12 of the exemplary embodiment of the present invention includes a plurality of first pipe sections, and the second steel pipe 22 includes a plurality of second pipe sections, and threads are provided at both ends of each first pipe section, so that the plurality of first pipe sections can be assembled to form the first steel pipe 12 according to the actual needs of the hole depth; threads are provided at both ends of each second pipe section, so that the plurality of second pipe sections can be assembled to form the second steel pipe 22 according to the actual needs of the hole depth. Exemplarily, the plurality of first pipe sections and the plurality of second pipe sections can be fixed in the form of sleeves, so that the length can be flexibly adjusted, increasing the flexibility and practicality of the test.

[0099] Exemplarily, the first tooling of the exemplary embodiment of the present invention further includes a first rubber tube, and the second tooling further includes a second rubber tube.

[0100] In practical applications, the wire of the first sensor is passed through the first rubber tube, and the first rubber tube is fixed at the central axis of the first steel tube; the wire of the second sensor is passed through the second rubber tube, and the second rubber tube is fixed at the central axis of the second steel tube. The rubber tube can not only further protect the sensor wire, but also reduce the transmission of vibration and impact. In the steel pipe, the sensor wire is fixed in the center of the pipe to avoid direct contact between the sensor wire and the steel pipe, thereby reducing wear and damage.

[0101] Step S400: starting the stress wave generator to generate a stress wave that propagates spherically.

[0102] After the stress wave generator is started, the data acquisition device collects the first stress value of the first sensor and the second stress value of the second sensor through the corresponding wire. The control device determines whether the first stress value is an accurate stress value based on the ratio of the first stress value and the second stress value measured at the same explosion center distance.

[0103] When the ratio of the first stress value to the second stress value is 1 to 1 / μ, it means that the first stress value is accurate, so the first stress value is stored; when it is not in the above range, it means that the first stress value is difficult to accurately reflect the actual stress value, and the data is discarded.

[0104] Specifically, the stress wave of the stress wave generator is equivalent to the stress wave generated by 1kg TNT explosive. The depth of the center hole is 1.6m. A set of typical stress time history curves are measured, such as Figure 6A-6B As shown, Fig. 6A is a stress of a first sensor test according to an embodiment of the present invention; Figure 6B is the stress of the second sensor test according to an embodiment of the present invention. γ is the explosion stress at a certain point, in MPa; t is the time, in ms; the brackets in the figure are the actual explosion center distance (the distance between the measurement point and the explosion center) R measured, in m. It can be seen that as the explosion center distance increases, the peak stress decreases; the curve presents a double wave structure. It should be noted that Fig. 6A The plane fixture in the figure refers to the stress curve of the first fixture. Figure 6B The pancake-shaped fixture in the figure refers to the stress curve of the second fixture.

[0105] Figure 7 is a peak stress fitting curve of the first sensor and the second sensor according to an embodiment of the present invention. Figure 7 As shown in the figure, the flat tooling refers to the first tooling, and the round tooling refers to the second tooling. The peak stress σ measured by the first sensor is B and the peak stress σ measured by the second sensor F Fitting is performed to obtain equation 9 and equation 10 respectively.

[0106] σ B =0.188Z -2.44 , formula nine;

[0107] σ F =0.123Z -2.26 , formula ten.

[0108] Where Z is the proportional distance in m·kg -1 / 3 , Z=R / Q 1 / 3 , where R is the distance between the measuring point and the explosion center, and Q is the TNT charge in kg.

[0109] As shown in Equations 9 and 10, the peak stress of the stress wave and the proportional distance satisfy the exponential decay law theoretically calculated in the engineering manual, that is, both the first sensor and the second sensor can accurately measure the stress wave in the rock and soil.

[0110] The exemplary embodiment of the present invention further provides a testing device for explosion stress waves in rock and soil at great depths, and the testing device executes the testing method of the above-mentioned embodiment.

[0111] like Figure 1-Figure 4 As shown, the test equipment includes a stress wave generator, a first tool and a second tool; wherein the first tool includes a first sensor, a first steel pipe 12 and a first plate 11 arranged at the bottom end of the first steel pipe 12, and a first surface of the first plate 11 has a first opening for exposing a first sensing surface 14 of the first sensor;

[0112] The second tooling includes a second steel tube 22 and a second plate 21 vertically arranged at the bottom end of the second steel tube 22, the second plate 21 having two second surfaces distributed along the first direction, the axial direction of the second steel tube 22 is perpendicular to the first direction, and one second surface has a second opening for exposing the second sensing surface 24 of the second sensor; the second plate 21 has a guide portion 211 surrounding the second sensing surface 24, and the thickness of the guide portion 211 gradually becomes thinner along the direction away from the second sensing surface 24.

[0113] The technical advantages of the above-mentioned testing equipment over the prior art are the same as the technical advantages of the testing method for explosion stress waves in deep rock and soil in the above-mentioned embodiment, which will not be repeated here.

[0114] It should be understood by those skilled in the art that the above embodiments are only for the purpose of clearly illustrating the present invention, and are not intended to limit the scope of the present invention. For those skilled in the art, other changes or modifications may be made based on the above disclosure, and these changes or modifications are still within the scope of the present invention.

Claims

1. A method for testing explosion stress waves in deep rock and soil, characterized in that: include: Providing a stress wave generator, a first tooling and a second tooling; Drilling a central hole and two measuring holes with the same hole depth in the rock soil, wherein the two measuring holes are at the same distance from the central hole; The stress wave generator is placed in the central hole, and the first tooling and the second tooling are placed in the two measuring holes respectively; wherein the first sensing surface and the edge of the guide portion away from the second steel pipe are both arranged opposite to the stress wave generator; A first stress value of the first sensor and a second stress value of the second sensor are collected.

2. The testing method according to claim 1, characterized in that: Placing the stress wave generator in the central hole, and placing the first tooling and the second tooling in the two measuring holes respectively, comprising: Lead the wire of the first sensor through the first steel pipe to the ground, and lead the wire of the second sensor through the second steel pipe to the ground; wherein part of the first steel pipe is located above the ground, and part of the second steel pipe is located above the ground.

3. The testing method according to claim 1, characterized in that: When a center hole and two measuring holes having the same hole depth are drilled in the rock soil, the method comprises: Two measuring holes are drilled, and the two measuring holes and the center hole are on the same straight line.

4. The testing method according to claim 3, characterized in that: When the stress wave generator is placed in the central hole and the first tooling and the second tooling are placed in the two measuring holes respectively, the method comprises: The first steel pipe and the second steel pipe are adjusted so that the center point of the first sensing surface of the first sensor, the center point of the second sensing surface of the second sensor, and the center point of the stress wave generator are located on the same horizontal plane.

5. The testing method according to claim 1, characterized in that: After the stress wave generator is placed in the central hole and the first tooling and the second tooling are respectively placed in the two measuring holes, the testing method further includes: The rock and soil are backfilled and compacted in the central hole and the two measuring holes.

6. The testing method according to claim 5, characterized in that: After backfilling and compacting the rock and soil in the center hole and the two measuring holes, the testing method further includes: The stress wave generator is started to generate a stress wave that propagates spherically.

7. The testing method according to any one of claims 1 to 6, characterized in that: The first tooling also includes a cross pipe, and the testing method further includes: Lead the wire of the first sensor through the transverse pipe and the first steel pipe to the ground.

8. The testing method according to claim 7, characterized in that: The first steel pipe includes a plurality of first pipe sections, the second steel pipe includes a plurality of second pipe sections, and the testing method further includes: The first steel pipe is formed by screwing a plurality of the first pipe segments together, and the second steel pipe is formed by screwing a plurality of the second pipe segments together.

9. The testing method according to claim 7, characterized in that: The first tooling also includes a first rubber tube, the second tooling also includes a second rubber tube, and the testing method further includes: Pass the wire of the first sensor through the first rubber tube, and fix the first rubber tube at the central axis of the first steel tube; The wire of the second sensor is passed through the second rubber tube, and the second rubber tube is fixed at the central axis of the second steel tube.

10. A testing device for explosion stress waves in deep rock and soil, characterized in that: The testing device executes the testing method according to any one of claims 1 to 9.

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