A calibration device for coupling effect of a seabed deformation monitoring probe and its working method

Abstract

This invention provides a calibration device and its working method for the coupling effect of a seabed deformation monitoring probe, comprising a soil trough, a built-in separate soil trough, and a propulsion device. Through the technical solution of this invention, this device can calibrate the deformation coupling effect between a seabed deformation monitoring probe and soils of different types (sand, silt, clay) and different states (consolidated state, liquefied state), making the in-situ monitoring data of seabed deformation more accurate and reliable. The hollow design of the built-in separate soil trough and the transparent material plate on the front of the soil trough enable visualization of the internal soil deformation. A displacement measuring device can accurately measure the actual deformation of the soil, thereby completing the comparison and correction of the monitoring probe measurement data. The propulsion device can control the soil deformation rate, and the pressure sensor can quantify the shear stress development process of soil deformation, further enabling the effectiveness analysis of the monitoring probe data during soil shear deformation and failure.

Description

Technical Field

[0001] This invention relates to the field of seabed monitoring technology, and more specifically, to a seabed deformation monitoring probe coupling effect calibration device and its working method. Background Technology

[0002] Estuaries, coastlines, and nearshore areas are concentrated areas for marine development and utilization. Their seabeds are mostly composed of loose sediments, making them susceptible to shear failure, liquefaction, and other instability failures under the influence of earthquakes, waves, and tides. This seriously threatens the safety and stability of marine engineering structures such as subsea pipelines, oil platforms, and wind turbine foundations. Therefore, exploring the catastrophic processes and mechanisms of seabed soil instability and failure, and conducting related in-situ monitoring research, is of significant scientific importance and engineering necessity. In recent years, seabed deformation monitoring technology has become a research focus both domestically and internationally. Among these, seabed lateral deformation monitoring technology has broad application prospects, leading to the development of sensing technologies such as flexible monitoring probes. The monitoring principle involves vertically burying the monitoring probe within the seabed. When lateral deformation occurs in the seabed, the soil causes strain in the probe. By measuring the lateral deformation of the probe through sensors, the lateral deformation of the seabed soil at different depths can be indirectly reflected.

[0003] Previous experiments have validated the accuracy of seabed deformation monitoring probes and the feasibility of in-situ monitoring technology, and the aforementioned monitoring technologies are relatively mature in terrestrial applications. However, seabed sediments are relatively loose, and may even become non-Newtonian fluids after instability and failure. Sliding deformation of the soil will inevitably cause displacement with the probe. Therefore, the coupling effect between the monitoring probe and soil in different states needs to be calibrated to correct deformation data, eliminate invalid data, and ensure that the monitoring data accurately quantifies the lateral deformation of the seabed soil. Currently, there is no publicly available calibration device capable of calibrating the coupling effect of seabed deformation monitoring probes. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, this invention provides a calibration device for the coupling effect of seabed deformation monitoring probes and its working method, which is used to calibrate the deformation coupling effect between various monitoring probes and soils of different types and states.

[0005] The present invention is achieved through the following technical solution: a seabed deformation monitoring probe coupling effect calibration device, comprising a soil trough, a built-in split soil trough, and a propulsion device;

[0006] The front of the trough is made of transparent acrylic sheet or tempered glass, and the other surfaces except the top are made of stainless steel sheet. A fixed base is set in the center of the bottom of the trough, and four guide rails are set on the back side of the trough.

[0007] The built-in separate soil troughs are set inside the soil troughs. Several built-in separate soil troughs are stacked vertically. Each built-in separate soil trough has a guide groove on the back. The guide groove is combined with the guide rail of the soil trough. The front, top and bottom sides of the built-in separate soil troughs are hollowed out. The stacked built-in separate soil troughs are seamlessly connected at the top and bottom through the guide rail and guide groove.

[0008] The number of propulsion devices is equal to that of the built-in separate soil troughs and they are located on the side of the soil troughs. Each propulsion device includes a propulsion rod, the end of which passes through the side of the soil trough and connects to each built-in separate soil trough. A pressure sensor is installed at the connection point. The propulsion device propels the built-in separate soil troughs to undergo lateral displacement.

[0009] Each built-in split soil trough has a displacement sensor installed at the connection point between its side wall and the corresponding push rod. A particle image velocimetry system is placed in front of the soil trough. The camera of the particle image velocimetry system is pointed at the front of the soil trough to capture the movement trajectory of the tracer particles in the soil and calculate the lateral displacement of the soil.

[0010] A monitoring probe is installed vertically upward on the fixed base, and the monitoring probe passes through the built-in split soil trench and the top surface of the soil trench from bottom to top.

[0011] As a preferred option, four sets of built-in separate soil troughs are provided.

[0012] As a preferred option, lubricant is installed inside the guide rail and guide groove.

[0013] As a preferred option, the other end of the push rod is connected to a push roller.

[0014] Furthermore, the propulsion rollers can be connected to an electric motor.

[0015] As a preferred option, the displacement sensor is either a high-precision laser displacement gauge or a mechanical displacement dial gauge.

[0016] As a preferred option, the monitoring probe is a rod section assembly structure with cables, and a triaxial acceleration sensor is installed at each node. The displacement of each node can be calculated based on the attitude changes of the sensor.

[0017] A method for calibrating the coupling effect of a seabed deformation monitoring probe includes the following steps:

[0018] S1: The calibration test uses sandy silt, which is air-dried, crushed, and sieved. Water is added at a mass ratio of 2.5:1 to prepare saturated mud samples with the same initial moisture content. The mud is filled into the soil tank and allowed to stand for different times to consolidate, in order to simulate soil in different states.

[0019] S2. Large visible particles are added to the front of the soil trough to prepare for the operation of the particle image velocity measurement system. After the preset consolidation time is reached, the propulsion device is turned on to push the built-in split soil trough to deform and move at a constant propulsion rate, with a propulsion displacement of 50-200mm.

[0020] S3. During the test, the actual displacement of the soil was calculated using a displacement sensor and a particle image velocity measurement system.

[0021] S4. After the test, samples are taken for geotechnical testing, and the parameters of the samples, including moisture content, density, and void ratio, are measured.

[0022] This invention, by employing the above technical solutions, offers the following advantages compared to existing technologies: The device enables calibration of the deformation coupling effect between the seabed deformation monitoring probe and soils of different types (sand, silt, clay) and states (consolidated, liquefied), resulting in more accurate and reliable in-situ seabed deformation monitoring data. The hollow design of the built-in, separate water tank and the transparent material plate on the front of the soil tank allow for visualization of the internal soil deformation. The displacement measuring device accurately measures the actual deformation of the soil, enabling comparison and correction of the monitoring probe's measurement data. The propulsion device controls the soil deformation rate, and the pressure sensor quantifies the shear stress development process of the soil deformation, further facilitating the analysis of the effectiveness of the monitoring probe data during soil shear deformation and failure.

[0023] Additional aspects and advantages of the invention will become apparent in the following description or may be learned by practice of the invention. Attached Figure Description

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0025] Figure 1 This is a schematic diagram of the structure of the present invention;

[0026] Figure 2 This is a front view structural diagram of the present invention;

[0027] Figure 3 This is a schematic diagram of the left-side structure of the present invention;

[0028] Figure 4 This is a top view of the structure of the present invention;

[0029] Figure 5 This is a structural diagram of the external casing;

[0030] Figure 6 This is a structural diagram of the internal box.

[0031] Figure 7This is a schematic diagram of the internal cross-section of the present invention from the left.

[0032] Figure 8 This is a schematic diagram of the device's outer casing and internal single-box structure.

[0033] in, Figures 1 to 7 The correspondence between the reference numerals and components in the attached drawings is as follows:

[0034] 1. Soil trough; 2. Built-in split soil trough; 3. Propulsion device; 4. Monitoring probe; 5. Fixed base; 6. Guide rail; 7. Guide groove; 8. Propulsion rod; 9. Pressure sensor; 10. Propulsion roller; 11. Displacement sensor; 12. Particle image velocimetry (PIV) system. Detailed Implementation

[0035] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0036] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0037] The following is combined Figures 1 to 7 The coupling effect calibration device for seabed deformation monitoring probes and its working method according to embodiments of the present invention will be described in detail.

[0038] like Figures 1 to 7 As shown, this invention proposes a calibration device and its working method for the coupling effect of a seabed deformation monitoring probe. Lateral deformation is applied to the soil through a separate soil trough in the calibration tank, and the deformation is directly measured (by dial gauge and image measurement). The measurement is then compared with the deformation measured by the fiber optic sensing probe to quantify and calibrate the coupling effect. The seabed deformation monitoring probe coupling effect calibration device includes a soil trough 1, a built-in separate soil trough 2, and a propulsion device 3.

[0039] The front of the soil trough 2 is made of transparent acrylic or tempered glass, while the other surfaces, except for the top, are made of stainless steel, allowing the deformation process of the built-in, separate soil trough to be displayed. A fixed base 5 is installed at the center of the bottom inside the soil trough 1 to fix the monitoring probe. Several guide rails 6 are installed on the back side inside the soil trough 1; the built-in, separate soil trough 2 moves laterally along the guide rails 6 under the drive of the propulsion device 3.

[0040] Four sets of built-in, separable soil troughs 2 are installed inside the soil trough 1. Several built-in, separable soil troughs 2 are stacked vertically. Each built-in, separable soil trough 2 has a guide groove 7 on its back, which connects to the guide rail 6 of the soil trough. The front, top, and bottom sides of the built-in, separable soil trough 2 are hollowed out, allowing the soil inside to be displayed through a transparent panel on the front side. The stacked built-in, separable soil troughs 2 are seamlessly connected vertically via the guide rail 6 and guide groove 7. Lubricating fluid is installed inside the guide rail 6 and guide groove 7 to minimize friction during lateral displacement of the built-in, separable soil troughs.

[0041] The number of propulsion devices 3 is equal to that of the built-in separate soil troughs 2 and they are located on the side of the soil trough 1. Each propulsion device 3 includes a propulsion rod 8, the end of which passes through the side of the soil trough 1 and connects to each built-in separate soil trough 2. A pressure sensor 9 is installed at the connection point. The propulsion device 3 propels the built-in separate soil trough 2 to achieve lateral displacement. The propulsion device 3 can be electric or manual. The other end of the propulsion rod 8 is connected to a propulsion roller 10. The propulsion roller 10 can be connected to an electric motor.

[0042] Each built-in separate soil trough 2 has a displacement sensor 11 installed at the connection point between its sidewall and the corresponding push rod 8. The displacement sensor 11 is either a high-precision laser displacement gauge or a mechanical displacement dial gauge. It obtains the lateral displacement of the built-in separate soil trough by measuring the change in distance between the separate soil trough and the sidewall of the trough, thereby indirectly characterizing the lateral displacement of the soil inside the built-in separate soil trough. A particle image velocimetry (PIV) system 12 is placed on the front side of the soil trough 2. The camera of the PIV system 12 is pointed at the front side of the soil trough 2 to capture the movement trajectory of tracer particles in the soil and calculate the lateral displacement of the soil.

[0043] A monitoring probe 4 is vertically mounted on the fixed base 5, passing through the top surfaces of the built-in separate soil trench 2 and soil trench 1 from bottom to top. The monitoring probe 4 is a rod-section assembly structure with cables, and a triaxial accelerometer is installed at each node. The displacement of each node can be calculated based on the attitude changes of the sensor.

[0044] A method for calibrating the coupling effect of a seabed deformation monitoring probe includes the following steps:

[0045] S1: The calibration test used sandy silt obtained in situ from the Yellow River Delta. It was air-dried, crushed, and sieved. Water was added at a mass ratio of 2.5:1 to prepare saturated mud samples with the same initial moisture content. The mud was filled into the soil tank and statically consolidated for different times Tc = 0, 0.5...1, 5, 10, 24h to simulate soil in different states.

[0046] S2. Large visible particles are added to the front of the soil trough to prepare for the operation of the Particle Image Velocity (PIV) system. After the preset consolidation time is reached, the propulsion device is activated to push the built-in split soil trough to deform and move at a constant propulsion rate, with a propulsion displacement of 50-200mm.

[0047] S3. During the test, the actual displacement of the soil was calculated using a displacement sensor and a particle image velocimetry (PIV) system.

[0048] S4. After the test, samples are taken for geotechnical testing, and the parameters of the samples, including moisture content, density, and void ratio, are measured.

[0049] The calibration tests simulated soil in different liquefaction states using different static consolidation times as control variables; the propulsion rate of the propulsion device was used as a control variable to simulate the deformation rate; and the pushing of different built-in separated soil troughs was used as a control variable to simulate the deformation depth. Through multiple sets of tests, the calibration method of the fiber optic sensing probe was systematically quantified, and a criterion system for the validity of the monitoring data was established.

[0050] In the description of this invention, the term "a plurality of" refers to two or more. Unless otherwise explicitly defined, the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. The terms "connection," "installation," "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0051] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0052] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A device for calibrating the coupling effect of a subsea deformation monitoring probe, characterized in that it comprises: Including soil tank (1), built-in separation type Soil tank (2), advancing device (3); The front side of the soil tank (2) is made of transparent acrylic plate or tempered glass, and the other surfaces except the top surface and the front side are made of stainless steel plate material, a fixed base (5) is arranged at the central position of the inner bottom of the soil tank (2), and a plurality of guide rails (6) are arranged on the back side of the soil tank (1); The built-in separation type soil tank (2) is arranged in the soil tank (1), a plurality of built-in separation type soil tanks (2) are vertically stacked, each built-in separation type soil tank (2) has a guide groove (7) on the back side, the guide groove (7) is combined with the guide rail (6) of the soil tank, the front side, the upper side and the lower side of the built-in separation type soil tank (2) are all designed as hollow, and the stacked built-in separation type soil tanks (2) are seamlessly combined through the guide rail (6) and the guide groove (7); The number of the advancing device (3) is equal to that of the built-in separation type soil tank (2) and is arranged on the side of the soil tank (1), the advancing device (3) comprises an advancing rod (8), the advancing rod (8) is connected with each built-in separation type soil tank (2) through the side of the soil tank (1), and a pressure sensor (9) is arranged at the connecting position, the built-in separation type soil tank (2) is horizontally displaced by the advancing device (3); A displacement sensor (11) is arranged at the connecting position of the side wall of each built-in separation type soil tank (2) and the corresponding advancing rod (8), a particle image velocimetry system (12) is arranged on the front side of the soil tank (2), and a camera of the particle image velocimetry system (12) faces the front side of the soil tank (2); A monitoring probe rod (4) is vertically arranged on the fixed base (5), and the monitoring probe rod (4) sequentially penetrates the top surface of the built-in separation type soil tank (2) and the soil tank (1) from bottom to top; the monitoring probe rod (4) is a rod joint combined structure with a cable, a three-axis acceleration sensor is arranged at each joint, and the displacement offset of each joint can be calculated according to the attitude change of the sensor.

2. The device according to claim 1, wherein, The built-in separation type soil tank (2) is provided with four groups.

3. The device according to claim 1, wherein, Lubricating liquid is arranged in the guide rail (6) and the guide groove (7).

4. The device according to claim 1, wherein, The other end of the advancing rod (8) is connected with an advancing roller (10).

5. The device according to claim 4, wherein, The advancing roller (10) can be connected with a motor.

6. The device according to claim 1, wherein, The displacement sensor (11) is one of a high-precision laser displacement meter and a mechanical displacement micrometer.

7. The working method of the seabed deformation monitoring probe coupling effect calibration device according to any one of claims 1-6, characterized in that, Specifically includes the following steps: S1: The calibration test adopts sandy silt, which is dried, crushed and sieved, and then water is added to prepare saturated mud samples with the same initial water content ratio, the mud is filled into the soil tank, and the soil tank is statically consolidated for different times Tc=0, 0.5…1, 5, 10, 24h to simulate different states of the soil body; S2, a large particle visible particle is added to the front side of the soil tank to prepare for the operation of the particle image velocimetry system; after reaching the preset consolidation time, the advancing device is started to push the built-in separation type soil tank to deform and move at a constant advancing speed, and the advancing displacement is 50-200mm; S3, the actual displacement of the soil body is measured by the displacement sensor and the particle image velocimetry system during the test; S4, after the end of the test, sampling for geotechnical test, measuring the sample including water content, density, porosity ratio parameters.

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