Triaxial test loading device and method with CPT function

Abstract

The invention discloses a triaxial test loading device and method with a CPT function, the device comprises a triaxial test loading machine and a static sounding test probe, the triaxial test loading machine comprises a sample chamber and an axial pressurization rod, and the axial pressurization rod is movably inserted in the sample chamber; the static sounding test probe is arranged at the front end of the axial pressurizing rod; wherein the sample chamber is used for storing a hydrate rock core sample; the axial pressurizing rod is used for applying a load to the hydrate core sample; the static sounding test probe is used for being inserted into the hydrate rock core sample along with the axial pressurizing rod and simultaneously performing in-situ testing on static sounding parameters of the hydrate rock core sample. According to the invention, the static cone penetration test probe and the triaxial test loading machine are combined together, the static cone penetration test is carried out on a hydrate rock core sample through the static cone penetration test probe, and the static cone penetration test can be completed while the triaxial test is realized through one-time ballasting.

Description

Technical Field

[0001] This invention relates to the field of marine geotechnical engineering technology, specifically to a triaxial testing loading device and method with CPT function. Background Technology

[0002] The hydrate pressure-holding triaxial testing system is mainly used for online mechanical property testing of natural hydrate cores. It can realize the pressure-holding transfer of actual hydrate cores, conduct triaxial shear tests, creep tests, and mechanical response analysis of hydrate core samples during decomposition, and obtain data such as strength, elastic modulus, cohesion, internal friction angle, and volumetric strain of hydrate core samples, as well as their influencing factors, including confining pressure, temperature, strain rate, saturation, pressure reduction, and heat injection. It can also conduct experimental research on the mechanical properties of hydrate remolded hydrate core samples, which is of great significance for analyzing the mechanical strength of marine hydrate cores and assessing the safety of hydrate mining.

[0003] However, current triaxial testing loaders have limitations in comprehensively understanding the properties of hydrate reservoirs. They can usually only perform a single type of test, namely, obtaining the mechanical properties of core samples through triaxial testing. But when the sample is a natural hydrate core sample, it is not possible to obtain the mechanical properties of the natural hydrate core sample through triaxial testing, and at the same time, it is not possible to conduct in-situ testing of other parameters of the hydrate core sample. For example, it is not possible to collect cone tip resistance, sidewall friction and pore pressure at different locations in the soil. Summary of the Invention

[0004] To address the aforementioned problems, the purpose of this invention is to provide a triaxial testing loading device with CPT function, which solves the problem that current triaxial testing loaders cannot simultaneously perform triaxial testing on samples to obtain the mechanical properties of hydrate core samples, and also perform in-situ testing on other parameters of hydrate core samples.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention discloses a triaxial testing loading device with CPT function, including... A triaxial test loader includes a sample chamber and an axial pressure rod, wherein the axial pressure rod is inserted into the sample chamber; A static cone penetration test probe is positioned at the front end of the axial compression rod; The sample chamber is used to store hydrate core samples; The axial compression rod is used to apply load to the hydrate core sample; The static cone penetration test probe is used to perform in-situ testing of the static cone penetration parameters of the hydrate core sample as it is inserted into the hydrate core sample with an axial pressure rod.

[0006] Preferably, the static cone penetration test probe includes a conical tip, a pore pressure filter ring, a cylinder, and a probe rod, which are assembled sequentially from front to back. The cone tip is equipped with a first pressure sensor for measuring the cone tip resistance; A second pressure sensor is provided on the side wall of the cylinder to measure the frictional resistance of the side wall; A pore is provided at the connection between the cone tip and the cylinder. A pore pressure filter ring is sleeved on the outside of the pore. A pore water inlet is provided on the pore pressure filter ring and is connected to the pore so that water can enter the pore through the pore water inlet to form pore water, which generates pore pressure. A pore pressure sensor is provided in the pore to measure the pore pressure of the pore water.

[0007] Preferably, during the process of the static cone penetration test probe being inserted into the hydrate core sample along with the axial pressure rod, when the static cone penetration test probe passes through the hydrate core sample, the first pressure sensor at the tip of the cone collects the cone tip resistance as it passes through the hydrate core sample, the second pressure sensor on the sidewall of the cylinder measures the sidewall friction resistance, and the pore pressure sensor inside the pore pressure filter ring measures the pore pressure of the pore water.

[0008] Preferably, the front end of the axial pressure rod is provided with a pressure cap, and the tail end of the static cone penetration test probe is disposed on the bottom surface of the pressure cap; wherein, the pressure cap is used to apply an axial load to the hydrate core sample.

[0009] Preferably, the bottom of the sample chamber is covered with a layer of filter stones, and the hydrate core sample is stored on the layer of filter stones.

[0010] Preferably, the triaxial test loader includes a power mechanism, which comprises a geared motor, a lead screw, an internal thread nut, and a sleeve. The output shaft of the geared motor is fixedly connected to the lead screw; The lead screw has an external thread on its outer wall, and the internal thread nut is sleeved on the outer wall of the lead screw and connected to the outer wall of the lead screw by a screw. The outer wall of the internal thread nut is fixedly connected to the outer wall of the sleeve; The inner wall of the sleeve is fixedly fitted onto the outer wall of the top end of the axial pressure rod.

[0011] Preferably, an anti-detachment block is provided between the inner wall of the sleeve and the outer wall of the axial pressure rod.

[0012] Preferably, a pressure sensor is provided between the outer wall of the axial pressure rod and the anti-detachment block.

[0013] Preferably, the triaxial test loader further includes a frame foundation. The framework foundation includes a base, four columns, and a rectangular frame. The base includes a top plate, which is rectangular, and the bottom ends of the four columns are respectively located at the four corners of the top plate of the base; The tops of the four pillars are fixedly connected as one unit by a rectangular frame; The geared motor is fixed on the rectangular frame; The lead screw passes through the rectangular frame and extends into the area enclosed by the four columns; The lower end of the axial pressure rod passes through the top plate of the base.

[0014] Preferably, the triaxial test loader further includes a triaxial pressure chamber, which includes an outer pressure chamber and a sample chamber. The sample chamber is located at the center of the outer pressure chamber and is connected to the outer pressure chamber. The external pressure chamber includes the base, and the lower end of the axial pressure rod passes through the top plate of the base and extends from top to bottom into the external pressure chamber and the sample chamber. The bottom of the external pressure chamber is connected to a pressurized water inlet pipe, and the sample chamber is connected to a drain pipe, which extends into the filter stone layer. A valve is installed at the outer end of the drain pipe.

[0015] Secondly, the present invention also discloses a triaxial test loading method with CPT function, providing the above-mentioned triaxial test loading device with CPT function, the method comprising the following steps: Step 1: Store the hydrate core sample in the sample chamber; Step 2: Start the geared motor. The geared motor drives the lead screw to rotate. The lead screw drives the internal thread nut to move up and down on it, which in turn drives the sleeve to move up and down, which in turn drives the axial pressure rod to move up and down. Step 3: The axial pressure rod applies axial pressure to the hydrate core sample, thereby applying an axial load to the hydrate core sample. Simultaneously, the outer pressure chamber of the triaxial pressure chamber applies confining pressure to the triaxial pressure chamber, including the outer pressure chamber. At the same time, the static cone penetration test probe is inserted into the hydrate core sample along with the axial pressure rod, and the static cone penetration test probe performs in-situ testing of the static cone penetration parameters of the hydrate core sample. During the process of the static cone penetration test probe being inserted into the hydrate core sample along with the axial pressure rod, as the static cone penetration test probe passes through the hydrate core sample, the first pressure sensor at the tip of the cone collects the cone tip resistance as it passes through the hydrate core sample, the second pressure sensor on the sidewall of the cylinder measures the sidewall friction resistance, and the pore pressure sensor inside the pore pressure filter ring measures the pore pressure of the pore water.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: (I) This invention discloses a triaxial test loading device with CPT function, including a triaxial test loader and a static cone penetration test probe. The triaxial test loader includes a sample chamber and an axial pressure rod, with the axial pressure rod inserted into the sample chamber. The static cone penetration test probe is located at the front end of the axial pressure rod. The sample chamber is used to store hydrate core samples. The axial pressure rod is used to apply load to the hydrate core sample from directly above it. The static cone penetration test probe is used to perform in-situ testing of the static cone penetration parameters of the hydrate core sample simultaneously with the insertion of the axial pressure rod into the hydrate core sample. This invention combines the static cone penetration test probe and the triaxial test loader, fixing the static cone penetration test probe at the front end of the axial pressure rod of the triaxial test loader. Static cone penetration testing of the hydrate core sample is performed using the static cone penetration test probe and its integrated sensor array. A single load application to the hydrate core sample achieves both triaxial testing and static cone penetration testing.

[0017] (II) This invention discloses a triaxial testing loading device with CPT (Conduction Penetration Test) function, which can not only complete triaxial testing and static cone penetration testing of shipborne hydrate pressurized cores, but also achieve multiple tests in a single pressurized core transfer. The device has a compact overall design, integrating triaxial loading, static cone penetration testing, pressurization, and environmental control functions, reducing the number of devices and improving work efficiency. It has practical significance in the analysis and acquisition of various physical property parameters of deep-sea pressurized cores.

[0018] (III) This invention discloses a triaxial test loading method with CPT function, comprising the following steps: Step 1: storing the hydrate core sample in the sample chamber; Step 2: starting the reduction motor, the reduction motor drives the lead screw to rotate, the lead screw drives the internal thread nut to move up and down on it, thereby driving the sleeve to move up and down, thereby driving the axial pressure rod to move up and down; Step 3: the axial pressure rod applies axial pressure to the hydrate core sample, thereby applying axial load to the hydrate core sample, and the outer pressure chamber of the triaxial pressure chamber applies confining pressure to the triaxial pressure chamber including the outer pressure chamber; at the same time, the static cone penetration test probe is inserted into the hydrate core sample along with the axial pressure rod, and the static cone penetration test probe performs in-situ testing of the static cone penetration parameters of the hydrate core sample. During the insertion of the static cone penetration test probe into the hydrate core sample along with the axial pressure rod, as the probe passes through the sample, a first pressure sensor at the tip of the cone collects the cone tip resistance as it passes through the sample, a second pressure sensor on the sidewall of the cylinder measures the sidewall friction, and a pore pressure sensor inside the pore pressure filter ring measures the pore pressure of the pore water. This invention discloses a triaxial testing loading method with CPT function, which solves the problem of not being able to collect the cone tip resistance, sidewall friction, and pore pressure at different locations in the soil while simultaneously performing triaxial testing to obtain the mechanical properties of the hydrate core sample. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the triaxial testing loading device with CPT function provided in Embodiment 1 of the present invention; Figure 2 yes Figure 1 A schematic diagram of the structure of the static cone penetration test probe; Figure 3 yes Figure 1 A magnified view of point A in the image; Figure 4 This is a schematic diagram of the structure of the triaxial pressure chamber provided in Embodiment 1 of the present invention.

[0020] Figure labeling: 100 - Sample chamber, 101 - Filter stone layer; 1-Axial pressure rod, 10-Pressure cap; 2-Static cone penetration test probe, 21-Conical tip, 22-Pore pressure filter ring, 220-Pore, 23-Cylinder, 24-Probe rod; 3-Power mechanism, 31-Gear motor, 32-Lead screw, 33-Internal thread nut, 34-Sleeve, 35-Anti-detachment block, 36-Pressure sensor; 4-Frame foundation, 41-Base, 42-Column, 43-Rectangular frame, 5-Triaxial pressure chamber, 50-External pressure chamber, 51-Pressurized water inlet pipe, 52-Drain pipe, 53-Valve. Detailed Implementation

[0021] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0022] To address the problem that current triaxial testing loaders cannot simultaneously perform triaxial testing to obtain the mechanical properties of hydrate core samples and conduct in-situ testing of other soil parameters of hydrate core samples, this invention introduces a static cone penetration test probe, namely a static cone penetration test (CPT) device.

[0023] The full name of the static cone penetration test (CPT) is a commonly used in-situ testing method in geotechnical engineering. Through CPT testing, static penetration parameters of hydrate core samples can be obtained. In addition to cone tip resistance, sidewall friction, and pore pressure at different locations in the soil, these parameters can also include many physical parameters of the hydrate core sample soil, such as shear strength, hydrate saturation, water content, salinity, and bearing capacity. This provides interpretation methods and theoretical support for CPT testing in actual deep-water strata.

[0024] It should be noted that the CPT function refers to the function of obtaining static cone penetration parameters of hydrate cores by testing the cone tip resistance, sidewall friction resistance and pore pressure at different locations in the soil using the probe of the static cone penetration test equipment.

[0025] This invention combines a triaxial test loader with a static cone penetration test probe 2, which enables multi-parameter core testing. This significantly enhances the testing capabilities and data breadth of existing shipborne triaxial test loaders, providing more technical means for refined analysis, resource prediction, and reservoir stability analysis of deep-water hydrate reservoirs in the field.

[0026] Example 1: A triaxial testing loading device with CPT function Embodiment 1 of the present invention provides a triaxial testing loading device with CPT function, and its structure is described in detail below with reference to the accompanying drawings.

[0027] refer to Figure 1 The triaxial test loading device with CPT function includes a triaxial test loading machine and a static cone penetration test probe 2.

[0028] The triaxial test loader includes a sample chamber 100 and an axial pressure rod 1, which is inserted into the sample chamber 100.

[0029] The static cone penetration test probe 2 is located at the front end of the axial pressure rod 1.

[0030] The sample chamber 100 is used to store hydrate core samples.

[0031] The axial pressure rod 1 is used to apply a load to the hydrate core sample from directly above it. Specifically, the applied load is an axial load.

[0032] The static cone penetration test probe 2 is used to perform in-situ testing of the static cone penetration parameters of the hydrate core sample as the axial pressure rod 1 is inserted into the hydrate core sample.

[0033] It should be noted that the static cone penetration parameters include the cone tip resistance, sidewall friction, and pore pressure at different locations in the soil. Because the static cone penetration test probe 2 and its equipment are highly functional, the static cone penetration parameters can also be parameters other than mechanical properties, such as shear strength, hydrate saturation, water content, salinity, and bearing capacity of hydrate core samples.

[0034] This invention combines a static cone penetration test probe 2 and a triaxial test loader. The static cone penetration test probe 2 is fixed to the front end of the axial pressure rod 1 of the triaxial test loader. The static cone penetration test is performed on the hydrate core sample by the static cone penetration test probe 2 and its internal integrated sensor group. The static cone penetration test is completed simultaneously with the triaxial test by loading the hydrate core sample.

[0035] Specifically, the static cone penetration test probe 2 is one of the main devices in the existing CPT technology. CPT stands for "Cone Penetration Test", which refers to the static cone penetration test or cone static penetration test, which involves pressing the probe into the soil at a certain rate using static force, and using the force sensor inside the probe to record the penetration resistance experienced by the probe through an electronic measuring instrument.

[0036] The static cone penetration test probe 2 is existing technology. It serves as a specific example of how this invention enables in-situ testing of other parameters of hydrate core samples. For instance, to address the problem of not being able to collect data on cone tip resistance, sidewall friction, and pore pressure at different locations in the soil while simultaneously obtaining the mechanical properties of the hydrate core sample through triaxial testing, reference is made to... Figure 2The static cone penetration test probe 2 includes a conical tip 21, a pore pressure filter ring 22, a cylinder 23, and a probe rod 24, which are assembled sequentially from front to back.

[0037] The cone tip 21 is equipped with a first pressure sensor for measuring the cone tip resistance; A second pressure sensor is provided on the side wall of the cylinder 23 to measure the frictional resistance of the side wall. A pore 220 is provided at the connection between the cone tip 21 and the cylinder 23. A pore pressure filter ring 22 is sleeved on the outside of the pore 220. A pore water inlet is provided on the pore pressure filter ring 22 and is connected to the pore 220 so that water can enter the pore through the pore water inlet to form pore water, and the pore water in the pore 220 generates pore pressure. A pore pressure sensor is provided inside the pore 220 and is used to measure the pore pressure of the pore water.

[0038] The process of the cone tip 21 of the static cone penetration test probe 2 passing through the hydrate core sample from top to bottom can realize the collection of cone tip resistance, side wall friction and pore pressure at different locations of the soil.

[0039] Specifically, during the process of the static cone penetration test probe 2 being inserted into the hydrate core sample along with the axial pressure rod 1, as the static cone penetration test probe 2 passes through the hydrate core sample, the first pressure sensor of the cone tip 21 collects the cone tip resistance as it passes through the hydrate core sample, the second pressure sensor on the side wall of the cylinder 23 measures the side wall friction, and the pore pressure sensor in the pore 220 inside the pore pressure filter ring 22 measures the pore pressure of the pore water.

[0040] As a specific way to connect the axial pressure rod 1 and the static penetration test probe 2, the front end of the axial pressure rod 1 is provided with a pressure cap 10, and the tail end of the static penetration test probe 2 is fixed on the bottom surface of the pressure cap 10.

[0041] The pressure cap 10 is used to apply axial load to the hydrate core sample.

[0042] The tail end of the static cone penetration test probe 2 is connected to the bottom surface of the pressure cap 10 via an electric push rod. When the electric push rod is extended or retracted, it can drive the static cone penetration test probe 2 to push out or retract from the bottom surface of the pressure cap 10.

[0043] Specifically, the bottom of the sample chamber 100 is covered with a filter stone layer 101, and the hydrate core sample is stored on the filter stone layer 101.

[0044] The triaxial test loader is also an existing technology, consisting of hardware and software components. The software component includes the control system and other software installed in the triaxial test loader, which can record, calculate and analyze the collected mechanical parameters.

[0045] Specifically, the hardware components of the triaxial test loader include a power mechanism 3, a frame foundation 4, and a triaxial pressure chamber 5.

[0046] refer to Figure 3 and combined Figure 1 The power mechanism 3 includes a geared motor 31, a lead screw 32, an internal thread nut 33, and a sleeve 34. The output shaft of the geared motor 31 is fixedly connected to the lead screw 32; The lead screw 32 has an external thread on its outer wall, and the internal thread nut 33 is sleeved on the outer wall of the lead screw 32 and connected to the outer wall of the lead screw 32 by a screw. The outer wall of the internal thread nut 33 is fixedly connected to the outer wall of the sleeve 34; The inner wall of the sleeve 34 is fixedly sleeved on the outer wall of the top end of the axial pressure rod 2.

[0047] To prevent the axial pressure rod 2 from falling off the inner wall of the sleeve 34, an anti-detachment block 35 is provided between the inner wall of the sleeve 34 and the outer wall of the axial pressure rod 2.

[0048] In order to detect the tensile or compressive load on the axial pressure rod 2 from the output bearing of the geared motor 31, a pressure sensor 36 is provided between the outer wall of the axial pressure rod 2 and the anti-detachment block 35.

[0049] To ensure the accuracy of stability control, measurement accuracy, and ease of operation during axial pressurization, the pressure sensor 36 is connected to the control system of the triaxial test loader.

[0050] Continue to refer to Figure 1 The frame foundation 4 includes a base 41, four columns 42, and a rectangular frame 43. The base 41 includes a top plate, which is rectangular, and the bottom ends of four columns 42 are respectively located at the four corners of the top plate of the base 41. The tops of the four columns 42 are fixedly connected as one unit by a rectangular frame 43.

[0051] Specifically, the geared motor 31 is fixed on the rectangular frame 43; the lead screw 32 extends through the rectangular frame 43 into the area enclosed by the four columns 42; and the lower end of the axial pressure rod 2 passes through the top plate of the base 41.

[0052] refer to Figure 4 and combined Figure 1 The triaxial pressure chamber 5 includes an outer pressure chamber 50 and a sample chamber 100. The sample chamber 100 is located at the center of the outer pressure chamber 50 and is connected to the outer pressure chamber 50. The external pressure chamber 50 includes the base 41, and the lower end of the axial pressure rod 2 passes through the top plate of the base 41 and extends from top to bottom into the external pressure chamber 50 and the sample chamber 100. The bottom of the external pressure chamber 50 is connected to a pressurized water inlet pipe 51, the sample chamber 100 is connected to a drain pipe 52, and the drain pipe 52 extends into the filter stone layer 101. A valve 53 is provided at the outer end of the drain pipe 52.

[0053] Specifically, the triaxial pressure chamber 5 is a self-balancing pressure chamber. The triaxial pressure chamber 5 is convenient for loading and unloading hydrate core samples and can directly measure the deformation of hydrate core samples. The triaxial pressure chamber 5 will not change or be affected when axial pressure or confining pressure is applied, so as to ensure the accuracy of the test.

[0054] Example 2: A triaxial testing loading method with CPT function Embodiment 2 of the present invention provides a triaxial test loading method with CPT function, and provides the triaxial test loading device with CPT function of Embodiment 1. The method includes the following steps: Step 1: Store the hydrate core sample in the sample chamber 100; Step 2: Start the reduction motor 31. The reduction motor 31 drives the lead screw 32 to rotate. The lead screw 32 drives the internal thread nut 33 to move up and down on it, which in turn drives the sleeve 34 to move up and down, which in turn drives the axial pressure rod 2 to move up and down. Step 3: The axial pressure rod 1 applies axial pressure to the hydrate core sample, thereby applying an axial load to the hydrate core sample. The outer pressure chamber 50 of the triaxial pressure chamber 5 applies confining pressure to the triaxial pressure chamber 5, including the outer pressure chamber 50. At the same time, the static cone penetration test probe 2 is inserted into the hydrate core sample along with the axial pressure rod 1, and the static cone penetration test probe 2 performs in-situ testing of the static cone penetration parameters of the hydrate core sample.

[0055] During the process of the static cone penetration test probe 2 being inserted into the hydrate core sample along with the axial pressure rod 1, as the static cone penetration test probe 2 passes through the hydrate core sample, the first pressure sensor of the cone tip 21 collects the cone tip resistance as it passes through the hydrate core sample, the second pressure sensor on the side wall of the cylinder 23 measures the side wall friction, and the pore pressure sensor in the pore 220 inside the pore pressure filter ring 22 measures the pore pressure of the pore water.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A triaxial testing loading device with CPT function, characterized in that, include The triaxial test loader includes a sample chamber (100) and an axial pressure rod (1), wherein the axial pressure rod (1) is inserted into the sample chamber (100); A static cone penetration test probe (2) is positioned at the front end of the axial pressure rod (1); The sample chamber (100) is used to store hydrate core samples; The axial pressure bar (1) is used to apply a load to the hydrate core sample; The static cone penetration test probe (2) is used to insert into the hydrate core sample along with the axial pressure rod (1) and simultaneously perform in-situ testing of the static cone penetration parameters of the hydrate core sample.

2. The triaxial testing loading device with CPT function according to claim 1, characterized in that, The static cone penetration test probe (2) includes a conical tip (21), a pore pressure filter ring (22), a cylinder (23), and a probe rod (24), which are assembled from front to back. The cone tip (21) is equipped with a first pressure sensor for measuring the cone tip resistance; The side wall of the cylinder (23) is provided with a second pressure sensor for measuring the frictional resistance of the side wall; A pore (220) is provided at the connection between the cone tip (21) and the cylinder (23). A pore pressure filter ring (22) is sleeved on the outside of the pore (220). A pore water inlet is provided on the pore pressure filter ring (22), and the pore water inlet is connected to the pore (220) so that water can enter the pore through the pore water inlet to form pore water, and the pore water in the pore (220) generates pore pressure. A pore pressure sensor is provided in the pore (220) to measure the pore pressure of the pore water.

3. The triaxial testing loading device with CPT function according to claim 2, characterized in that, During the process of the static cone penetration test probe (2) being inserted into the hydrate core sample along with the axial pressure rod (1), when the static cone penetration test probe (2) passes through the hydrate core sample, the first pressure sensor of the cone tip (21) collects the cone tip resistance passing through the hydrate core sample, the second pressure sensor of the side wall of the cylinder (23) measures the side wall friction, and the pore pressure sensor of the pore (220) inside the pore pressure filter ring (22) measures the pore pressure of the pore water.

4. The triaxial testing loading device with CPT function according to claim 3, characterized in that, The front end of the axial pressure rod (1) is provided with a pressure cap (10), and the tail end of the static penetration test probe (2) is set on the bottom surface of the pressure cap (10); The pressure cap (10) is used to apply an axial load to the hydrate core sample.

5. The triaxial testing loading device with CPT function according to claim 1, characterized in that, The bottom of the sample chamber (100) is covered with a layer of filter stone (101), and the hydrate core sample is stored on the layer of filter stone (101).

6. The triaxial testing loading device with CPT function according to claim 1, characterized in that, The triaxial test loader includes a power mechanism (3). The power mechanism (3) includes a geared motor (31), a lead screw (32), an internal thread nut (33), and a sleeve (34). The output shaft of the geared motor (31) is fixedly connected to the lead screw (32); The lead screw (32) has an external thread on its outer wall, and the internal thread nut (33) is sleeved on the outer wall of the lead screw (32) and connected to the outer wall of the lead screw (32) by a screw. The outer wall of the internal thread nut (33) is fixedly connected to the outer wall of the sleeve (34); The inner wall of the sleeve (34) is fixedly sleeved on the outer wall of the top end of the axial pressure rod (2).

7. The triaxial testing loading device with CPT function according to claim 6, characterized in that, An anti-detachment block (35) is provided between the inner wall of the sleeve (34) and the outer wall of the axial pressure rod (2); A pressure sensor (36) is provided between the outer wall of the axial pressure rod (2) and the anti-detachment block (35).

8. The triaxial testing loading device with CPT function according to claim 5, characterized in that, The triaxial test loader also includes a frame foundation (4). The frame foundation (4) includes a base (41), four columns (42) and a rectangular frame (43). The base (41) includes a top plate, which is rectangular, and the bottom ends of the four columns (42) are respectively located at the four corners of the top plate of the base (41); The tops of the four columns (42) are fixedly connected to each other by a rectangular frame (43); The geared motor (31) is fixed on the rectangular frame (43); The lead screw (32) passes through the rectangular frame (43) and extends into the area enclosed by the four columns (42); The lower end of the axial pressure rod (2) passes through the top plate of the base (41).

9. The triaxial testing loading device with CPT function according to claim 8, characterized in that, The triaxial test loader also includes a triaxial pressure chamber (5). The triaxial pressure chamber (5) includes an outer pressure chamber (50) and a sample chamber (100). The sample chamber (100) is located at the center of the outer pressure chamber (50) and is connected to the outer pressure chamber (50). The external pressure chamber (50) includes the base (41), and the lower end of the axial pressure rod (2) passes through the top plate of the base (41) and extends from top to bottom into the external pressure chamber (50) and the sample chamber (100). The bottom of the external pressure chamber (50) is connected to a pressurized water inlet pipe (51), the sample chamber (100) is connected to a drain pipe (52), and the drain pipe (52) extends into the filter stone layer (101). A valve (53) is provided at the outer end of the drain pipe (52).

10. A triaxial test loading method with CPT function, providing the triaxial test loading device with CPT function as described in claim 9, the method comprising the following steps: Step 1: Store the hydrate core sample in the sample chamber (100); Step 2: Start the geared motor (31), the geared motor (31) drives the lead screw (32) to rotate, the lead screw (32) drives the inner thread nut (33) to move up and down on it, thereby driving the sleeve (34) to move up and down, and thus driving the axial pressure rod (2) to move up and down; Step 3: The axial pressure rod (1) applies axial pressure to the hydrate core sample, thereby applying an axial load to the hydrate core sample. The outer pressure chamber (50) of the triaxial pressure chamber (5) applies confining pressure to the triaxial pressure chamber (5), including the outer pressure chamber (50). At the same time, the static penetration test probe (2) is inserted into the hydrate core sample along with the axial pressure rod (1), and the static penetration test probe (2) performs in-situ testing of the static penetration parameters of the hydrate core sample. During the process of the static cone penetration test probe (2) being inserted into the hydrate core sample along with the axial pressure rod (1), when the static cone penetration test probe (2) passes through the hydrate core sample, the first pressure sensor of the cone tip (21) collects the cone tip resistance passing through the hydrate core sample, the second pressure sensor of the side wall of the cylinder (23) measures the side wall friction, and the pore pressure sensor of the pore (220) inside the pore pressure filter ring (22) measures the pore pressure of the pore water.

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