CN-224231571-U - Seabed sediment porosity and sound attenuation characteristic ballast measuring device

CN224231571UCN 224231571 UCN224231571 UCN 224231571UCN-224231571-U

Abstract

The utility model relates to the field of submarine acoustic detection, and particularly discloses a submarine sediment porosity and sound attenuation characteristic ballast measuring device which comprises a pressurizing device, a testing device, an acoustic measuring device, a porosity change measuring device, a motor driving device and a PC (personal computer) upper computer, wherein the devices are cooperated to realize the measurement of porosity and sound attenuation characteristic of sediment samples under the action of pressure. The device provided by the utility model adopts the contact type multi-sensor measurement, avoids disturbance to the internal structure and property of the sediment in the traditional sampling process, ensures the originality and the authenticity of measurement data, more accurately reflects the natural state of the submarine sediment in a pressure environment, and can monitor the change of the porosity, the density and the acoustic characteristic of the sediment under pressure loading in real time.

Inventors

WANG MAO
ZOU DAPENG
WANG YONG
ZHANG LI
JIANG YONGJUN

Assignees

广东工业大学
中国科学院武汉岩土力学研究所

Dates

Publication Date: 20260512
Application Date: 20250523

Claims (10)

1. The device is characterized by comprising a pressurizing device, a testing device, an acoustic measuring device, a porosity change measuring device, a motor driving device and a PC upper computer, wherein the devices work cooperatively to realize the measurement of the porosity and the acoustic attenuation characteristic of a sediment sample under the action of pressure.
2. A seabed sediment porosity and sound attenuation characteristic ballast measuring device according to claim 1, wherein the pressurizing device is composed of three pressurizing units of confining pressure, back pressure and axial pressure, each pressurizing unit comprises a motor, a pressurizing cylinder, a water inlet valve and a water outlet valve, and the pressurizing units are used for realizing pressure loading of sediment samples in the test chamber.
3. The device of claim 1, wherein the testing device comprises a testing chamber for simulating a subsea sediment in-situ pressure environment, a sample carrying module for carrying and holding sediment samples, an axial force sensor, a displacement sensor, an axial pressure loading cylinder, upper and lower end caps, and support posts.
4. The device for measuring the porosity and acoustic attenuation characteristics of a seabed sediment according to claim 1, wherein the acoustic measuring device comprises an acoustic wave meter, a transmitting transducer, a receiving hydrophone 1 and a receiving hydrophone 2, and one transmitting transducer and two receiving hydrophones comprise a transmitting and receiving measuring system for measuring the sound velocity and the acoustic attenuation coefficient of the sediment sample.
5. The device for measuring the porosity and sound attenuation characteristics of the seabed sediment according to claim 1, wherein the porosity variation measuring device mainly comprises a pressure sensor, an axial force sensor, a displacement sensor and a flowmeter, and is used for measuring confining pressure, back pressure, pore pressure, axial force, sample displacement and pore water drainage volume parameters in the experimental process, the pressure sensor of the porosity variation measuring device is respectively arranged on a confining pressure system, a back pressure system and an axial pressure system of a test cabin, the axial force sensor is arranged at the top of the test cabin, the displacement sensor is arranged at the lower part of an axial pressure loading cylinder, and the flowmeter is arranged between the pressurizing device and the pressure sensor.
6. The device for measuring the porosity and sound attenuation characteristics of a seabed sediment according to claim 1, wherein the motor driving device is used for driving the motor of the pressurizing device to operate, so as to realize loading and adjusting of pressure.
7. The device for measuring the porosity and sound attenuation characteristics of the seabed sediment according to claim 1, wherein the PC upper computer comprises a control center and a data processing unit for controlling and receiving parameters of each sensor, the sound wave instrument and the motor driving device, and calculating and analyzing the porosity, the density, the sound velocity and the sound attenuation of the sediment sample.
8. The device for measuring the porosity and sound attenuation characteristics of the seabed sediment according to claim 1, wherein the pressurizing device is connected with the testing cabin through upper and lower end covers of the testing cabin, and the axial pressure loading cylinder directly extends into the testing cabin through a piston rod to be connected with the sample bearing module for applying axial pressure to the sediment sample.
9. A seabed sediment porosity and sound attenuation characteristic ballast measuring device according to claim 3, wherein the sample bearing module comprises an upper transducer assembly, a lower transducer assembly, a latex film and a sediment sample placing chamber, the upper transducer assembly comprises a transducer base, a pore pressure measuring hole, a transducer gland and an acoustic transducer, the transducer base is connected with the transducer gland through bolts, the acoustic transducer is clamped by the transducer gland and the transducer base, an L-shaped transducer wiring hole is embedded in the transducer assembly, the bottom of the transducer wiring hole is attached to the acoustic transducer, annular permeable stones are arranged on the left side and the right side of the acoustic transducer, the pore pressure measuring hole is connected with the annular permeable stones on the left side of the acoustic transducer, and the lower transducer assembly comprises a transducer base, a back pressure pressurizing hole, a transducer gland and the acoustic transducer, and the back pressure pressurizing hole is connected with the annular permeable stones on the left side of the acoustic transducer.
10. The apparatus of claim 9, wherein the latex film encloses the transducer assembly and the sediment sample placement chamber, and the receiving hydrophone 1 and the receiving hydrophone 2 are placed under the sediment sample, and the receiving hydrophone 1 and the receiving hydrophone 2 are placed on top of the acoustic transducers of the lower transducer assembly.

Description

Seabed sediment porosity and sound attenuation characteristic ballast measuring device Technical Field The utility model relates to the technical field of submarine acoustic detection, in particular to a ballast measuring device for the porosity and sound attenuation characteristics of submarine sediments. Background The seabed sediment belongs to a water saturated two-phase porous medium which is widely distributed on the seabed. The study of the acoustic-pressure characteristics of the subsea sediment plays a key role in marine exploration, engineering construction and resource development. Under the environment of different depths of the seabed, the internal pore structure and density of the seabed can be influenced by deep water pressure, so that the propagation speed and attenuation characteristic of sound waves are changed. The acoustic response is an important index for identifying the type of the submarine sediment, forecasting the change of the mechanical property of the submarine sediment and evaluating the stability of the sediment, and has important reference significance for detecting the structure and the physical state of the submarine stratum. In the fields of deep sea oil gas resource exploration, submarine tunnel construction and the like, acoustic-pressure characteristic data of sediment are directly related to detection precision and engineering safety. However, conventional acoustic measurements are typically performed only under atmospheric conditions, or sampling measurements after pressurization, resulting in measured data that does not truly reflect acoustic properties in a deep sea high pressure environment. In the field of marine sediment characteristic research, the traditional measurement technology has four core defects of environment simulation distortion, dynamic process monitoring blind areas, insufficient multi-field coupling analysis and measurement dimension singleization. The traditional method is mostly carried out in an atmospheric laboratory environment or is carried out by sampling detection after pressurization. This approach ignores the significant impact of deep sea high pressures (typically up to tens of MPa) on the sediment skeletal structure. Experiments show that when the confining pressure exceeds 10MPa, the arrangement mode of clay mineral particles can be irreversibly changed, so that nonlinear offset is generated in the acoustic wave propagation path. The existing device mostly adopts a static mode of pressurization, pressure maintaining and measurement, and cannot capture the key stage of dynamic adjustment of effective stress of particles in the process of discharging pore water. According to the International Association of sediment study (ISSA), 82% of acoustic parameter variation occurred within 2 hours of the initial pressure loading. Therefore, there is a need to develop a device for measuring the porosity and acoustic attenuation characteristics of a subsea sediment, which captures the acoustic response of the sediment in real time during compression, providing more realistic and dynamic acoustic-pressure characteristic data. The research provides scientific support for the fields of ocean engineering and exploration, improves the accuracy of submarine exploration, and provides a solid foundation for future ocean resource development and engineering. Disclosure of utility model The utility model aims at the problems in the prior art, and provides a device for measuring the porosity and sound attenuation characteristics of a seabed sediment, which can accurately reflect the natural state of the seabed sediment in a pressure environment and can monitor the porosity, density and acoustic characteristic change of the sediment under pressure loading in real time. In order to achieve the above purpose, the utility model provides a ballast measuring device for the porosity and the sound attenuation characteristics of a seabed sediment, which comprises a pressurizing device, a testing device, an acoustic measuring device, a porosity change measuring device, a motor driving device and a PC (personal computer) host computer, wherein the devices are cooperated to realize the measurement of the porosity and the sound attenuation characteristics of the sediment sample under the action of pressure. Preferably, the pressurizing device is composed of three pressurizing units of confining pressure, back pressure and axial pressure, and each pressurizing unit comprises a motor, a pressurizing cylinder, a water inlet valve and a water outlet valve and is used for realizing pressure loading on sediment samples in the test cabin. Preferably, the testing device comprises a testing cabin, a sample bearing module, an axial force sensor, a displacement sensor, an axial pressure loading cylinder, an upper end cover, a lower end cover and a supporting upright post, wherein the testing cabin is used for simulating the in-situ pressure environment of the submarine sediment, an