High-temperature and high-pressure electricity-seepage-force combined measurement test device and use method thereof

Abstract

The invention discloses a high-temperature and high-voltage electricity-seepage-force combined measurement test device which comprises a test chamber and a combined measurement system, a test cavity is formed in the test chamber, and a piston opening is formed in the bottom of the test chamber; the other end of the loading piston rod penetrates through the piston opening and is positioned in the test cavity; one end of the combined measurement system abuts against the other end of the loading piston rod, and the other end of the combined measurement system is in contact connection with the bottom of the test cavity; a rock sample is placed in the combined measurement system so as to measure the resistivity, permeability and strain of the rock sample. The invention further discloses a use method of the high-temperature and high-pressure electricity-seepage-force combined measurement test device. Compared with the prior art, the high-temperature and high-pressure electricity-permeability-force combined measurement test device has the advantage of simultaneously measuring the resistivity, permeability and strain of a rock sample in a high-temperature and high-pressure environment.

Description

Technical Field

[0001] The present invention relates to the technical field of rock test devices, and in particular to a high-temperature and high-pressure electro-osmotic-force combined measurement test device and a method for using the same. Background Art

[0002] The resistivity, permeability, and mechanical characteristics of rocks are important technical means in geotechnical engineering, oil exploration, and geological exploration. The combined measurement of these three physical parameters provides multi-dimensional information on rocks and formations, and is of great significance for understanding the physical properties of rocks, fluid penetration characteristics, pore structures, etc.

[0003] Currently, the measurement of rock resistivity, permeability, and mechanical characteristics needs to be carried out in different experimental devices, and multiple rock cores need to be used for testing respectively. However, rocks have uncontrollable non-homogeneous characteristics. To study the relationship between the three physical properties, testing needs to be carried out under the same experimental conditions in the same experimental device. Currently, there are few experimental devices that can simultaneously measure the three parameters. At the same time, as underground engineering continues to move deeper, the temperature and pressure environment of rocks is constantly increasing. There are very few experimental devices that can simultaneously measure the three parameters of rock resistivity, permeability, and mechanical characteristics under high-temperature and high-pressure conditions.

[0004] Therefore, how to provide a high-temperature and high-pressure electro-osmotic-force combined measurement test device that can achieve the technical effect of simultaneously measuring electro-osmotic-force under high-temperature and high-pressure conditions is a technical problem that needs to be urgently solved by those skilled in the art. Summary of the Invention

[0005] In view of the problems existing in the prior art, the technical problem to be solved by the present invention is to provide a high-temperature and high-pressure electro-osmotic-force combined measurement test device that can achieve the technical effect of simultaneously measuring electro-osmotic-force under high-temperature and high-pressure conditions.

[0006] To achieve the above object, the present invention provides a high-temperature and high-pressure electro-osmotic-force combined measurement test device. The high-temperature and high-pressure electro-osmotic-force combined measurement test device includes: a test chamber, a test cavity is opened inside the test chamber, the test cavity has a cylindrical structure, a piston port is opened at the bottom of the test chamber, and the piston port communicates with the test cavity; a loading piston rod, one end of the loading piston rod is connected to an axial pressure loader, and the other end of the loading piston rod passes through the piston port and is located inside the test cavity; a combined measurement system, the combined measurement system is located inside the test cavity, one end of the combined measurement system abuts against the other end of the loading piston rod, and the other end of the combined measurement system is in contact connection with the bottom of the test cavity; a rock sample is placed inside the combined measurement system to measure the resistivity, permeability, and strain of the rock sample.

[0007] In a first aspect, the combined measurement system includes: a first electrically insulating sheet, the upper end surface of the first electrically insulating sheet abuts against the other end of the loading piston rod; an upper platen, the upper end surface of the upper platen abuts against the lower end surface of the first electrically insulating sheet, and the lower end surface of the upper platen abuts against the upper end surface of the rock specimen; a lower platen, the upper end surface of the lower platen abuts against the lower end surface of the rock specimen; a second electrically insulating sheet, the upper end surface of the second electrically insulating sheet abuts against the lower end surface of the lower platen, and the lower end surface of the second electrically insulating sheet is in contact connection with the bottom of the test cavity.

[0008] In a first aspect, an upper electrode insertion opening is formed on one side of the upper platen, and an upper seepage channel penetrating through the upper platen is formed inside the upper platen. One end of the upper seepage channel is located on the other side of the upper platen, and the other end of the upper seepage channel is located on the lower end surface of the upper platen.

[0009] In a first aspect, a lower electrode insertion opening is formed on one side of the lower platen, and a lower seepage channel penetrating through the lower platen is formed inside the lower platen. One end of the lower seepage channel is located on the other side of the lower platen, and the other end of the lower seepage channel is located on the upper end surface of the lower platen.

[0010] In a first aspect, the combined measurement system further includes an electrode assembly, and the electrode assembly includes: an upper electrode disposed in the upper electrode insertion opening; an upper wire, one end of the upper wire is connected to the upper electrode; a lower electrode disposed in the lower electrode insertion opening; a lower wire, one end of the lower wire is connected to the lower electrode; wherein, two aviation plugs are provided at the bottom of the test chamber, and the other ends of the upper wire and the lower wire are respectively connected to a corresponding one of the aviation plugs.

[0011] In a first aspect, the combined measurement system further includes a seepage assembly, and the seepage assembly includes: an upper seepage sealing joint, one end of the upper seepage sealing joint is hermetically connected to one end of the upper seepage channel; an upper seepage pipeline, one end of the upper seepage pipeline is hermetically connected to the other end of the upper seepage sealing joint; a lower seepage sealing joint, one end of the lower seepage sealing joint is hermetically connected to one end of the lower seepage channel; a lower seepage pipeline, one end of the lower seepage pipeline is hermetically connected to the other end of the lower seepage sealing joint; wherein, a seepage inlet channel and a seepage outlet channel are further provided at the bottom of the test chamber. The other end of the upper seepage pipeline passes through the seepage outlet channel and is connected to an upper pore pressure pump, and the other end of the lower seepage pipeline passes through the seepage inlet channel and is connected to a lower pore pressure pump; the upper seepage pipeline and the lower seepage pipeline are respectively hermetically and insulatingly connected to the seepage outlet channel and the seepage inlet channel.

[0012] In a first aspect, the combined measurement system further includes a silicone rubber sleeve. One end of the silicone rubber sleeve is sleeved on the outer periphery of the lower part of the upper platen, and the other end of the silicone rubber sleeve is sleeved on the outer periphery of the upper part of the lower platen, so that the silicone rubber sleeve is sleeved on the outer periphery of the rock specimen; both the upper platen and the lower platen are hermetically connected to the silicone rubber sleeve.

[0013] In a first aspect, the combined measurement system further includes a strain component. The strain component is located inside the silicone rubber sleeve. The strain component includes: two groups of strain measuring elements. Both groups of strain measuring elements are fixed on the side surface of the rock specimen. One group of strain measuring elements is arranged along the axial direction of the rock specimen, and the other group of strain measuring elements is arranged along the circumferential direction of the rock specimen; each group of strain measuring elements includes two strain gauges, and the two strain gauges in each group are arranged in parallel; wherein, the side of the silicone rubber sleeve has a number of silicone rubber protrusions, and strain wire outlets are provided in any two of the silicone rubber protrusions located on the side surface of the rock specimen, so that the wires of each group of strain gauges pass through the corresponding strain wire outlets, and the wires of each group of strain gauges are hermetically connected to the strain wire outlets.

[0014] The present invention also provides a method for using a high-temperature and high-pressure electro-osmosis-force combined measurement test device for the use of the above-mentioned high-temperature and high-pressure electro-osmosis-force combined measurement test device. The method for using includes: without installing a rock specimen in the test cavity, performing high-temperature and high-pressure calibration on the inherent resistance of the upper electrode and the lower electrode; mounting the strain component on the rock specimen, then installing it in the test cavity, turning on the strain measurement, and then heating and pressurizing the inside of the test cavity so that the temperature and pressure inside the test cavity both reach the test parameters. Then, apply pore pressure to the upper seepage seal joint and the lower seepage seal joint respectively through the upper pore pressure pump and the lower pore pressure pump. After the pore pressure of the upper seepage seal joint and the pore pressure of the lower seepage seal joint are stable, measure the resistivity and permeability respectively; then apply axial pressure to the rock specimen and test the resistivity and permeability; the applying axial pressure to the rock specimen and testing the resistivity and permeability specifically include: applying axial pressure until the rock specimen yields or fractures, and then testing the resistivity and permeability; or, applying axial pressure to the rock specimen in stages and testing the resistivity and permeability under each stage of axial pressure condition.

[0015] In a second aspect, the mounting the strain component on the rock specimen specifically includes: first leveling and polishing the side surface of the rock specimen with a high-temperature repair agent; then pasting strain gauges on the side of the rock specimen with a high-temperature patch glue; and finally coating a high-temperature protective glue on the surface of the pasted strain gauges.

[0016] Beneficial effects:

[0017] A high-temperature and high-pressure electro-osmotic-force combined measurement test device of the present invention mainly includes a test chamber, a loading piston rod, and a combined measurement system; a test cavity is provided inside the test chamber, and the test chamber also includes a test chamber shell and a base. One end of the test chamber shell is hermetically connected to the base, and a piston port is provided at the other end of the test chamber shell. The test chamber shell and the base enclose the test cavity; a heating jacket is provided close to the test chamber shell of the test chamber to heat the test chamber shell, so as to heat and keep warm the inside of the test cavity. A heat preservation jacket is provided outside the heating jacket for heat preservation; the test cavity is used to place a rock sample, and a thermocouple is provided inside the test cavity for monitoring the temperature inside the test cavity; a heating circulation inlet and a pressure inlet are provided on the base, and a heating circulation outlet is provided at the top of the test chamber shell. The heating circulation inlet, the pressure inlet, and the heating circulation outlet are all communicated with the test cavity. Heating liquid is introduced into the test cavity through the heating circulation inlet and flows out through the heating circulation outlet to circulate the heating liquid in the test cavity, so as to achieve the setting of the temperature in the test cavity, and combined with the heating jacket and the heat preservation jacket, the heating temperature is made more accurate; when the temperature in the test cavity reaches the experimental target temperature, pressurized liquid is introduced through the pressure inlet to apply confining pressure to the rock sample, so that the rock sample is in a high-temperature and high-confining-pressure environment. The loading piston rod is used to apply axial pressure to the rock sample, so that the rock sample is in a high-temperature and high-pressure environment; the combined measurement system is used to measure the resistivity, permeability, and strain of the rock sample; in summary, a high-temperature and high-pressure electro-osmotic-force combined measurement test device of the present invention realizes the simultaneous measurement of the resistivity, permeability, and strain of the rock under a high-temperature and high-pressure environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present specification or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0019] Figure 1 It is a schematic connection structure diagram of the test chamber, the loading piston rod, and the combined measurement system of the present invention;

[0020] Figure 2 It is a schematic structure diagram of the combined measurement system of the present invention;

[0021] Figure 3 It is a schematic installation diagram of the surface strain gauge of the rock sample of the present invention;

[0022] Figure 4 It is a schematic structure diagram of the test chamber of the present invention.

[0023] Reference numerals:

[0024] 1. Test chamber; 101. Test cavity; 102. Piston port; 103. Test chamber shell; 104. Base

[0025] 2. Loading piston rod

[0026] 3. Combined measurement system; 301. First electrical insulation sheet; 302. Upper pressure head; 303. Lower pressure head; 304. Second electrical insulation sheet; 305. Upper seepage channel; 306. Lower seepage channel; 307. Upper electrode; 308. Lower electrode; 309. Upper seepage sealing joint; 310. Lower seepage sealing joint; 311. Silicone rubber sleeve; 312. Strain gauge

[0027] 4. Rock sample

[0028] 001. Strain wire outlet; 002. High-temperature repair agent; 003. High-temperature patch glue; 004. High-temperature protective glue Specific implementation mode

[0029] Next, the technical solutions in the embodiments of this specification will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of this specification. Obviously, the described embodiments are only a part of the embodiments of this specification, rather than all the embodiments. Based on the embodiments in this specification, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present invention

[0030] Embodiment 1

[0031] As Figures 1 to 4 shown, Embodiment 1 of the present invention provides a high-temperature and high-pressure electro-osmotic-force combined measurement test device. The high-temperature and high-pressure electro-osmotic-force combined measurement test device includes: a test chamber 1, inside which a test cavity 101 is provided. The test cavity 101 has a cylindrical structure. A piston port 102 is provided at the bottom of the test chamber 1, and the piston port 102 communicates with the test cavity 101. A loading piston rod 2, one end of the loading piston rod 2 is connected to an axial pressure loader, and the other end of the loading piston rod 2 passes through the piston port 102 and is located inside the test cavity 101. A combined measurement system 3, the combined measurement system 3 is located inside the test cavity 101. One end of the combined measurement system 3 abuts against the other end of the loading piston rod 2, and the other end of the combined measurement system 3 is in contact connection with the bottom of the test cavity 101. A rock sample 4 is placed inside the combined measurement system 3 to measure the resistivity, permeability and strain of the rock sample 4

[0032] A high-temperature and high-pressure electro-osmotic-force combined measurement test device of the present invention mainly includes a test chamber 1, a loading piston rod 2, and a combined measurement system 3; a test cavity 101 is provided inside the test chamber 1, and the test chamber 1 further includes a test chamber shell 103 and a base 104. One end of the test chamber shell 103 is hermetically connected to the base 104, and a piston port 102 is provided at the other end of the test chamber shell 103. The test chamber shell 103 and the base 104 enclose the test cavity 101; a heating jacket is provided around the outer periphery of the test chamber shell 103 of the test chamber 1 to heat the test chamber shell 103, so as to heat and keep warm the inside of the test cavity 101. A heat preservation jacket is provided around the heating jacket for heat preservation; the test cavity 101 is used to place a rock sample 4, and a thermocouple is provided in the test cavity 101 for monitoring the temperature in the test cavity 101; a heating circulation inlet and a pressurization inlet are provided on the base 104, and a heating circulation outlet is provided at the top end of the test chamber shell 103. The heating circulation inlet, the pressurization inlet, and the heating circulation outlet are all communicated with the test cavity. Heating liquid is introduced into the test cavity 101 through the heating circulation inlet and flows out through the heating circulation outlet for the heating liquid to circulate in the test cavity 101, so as to achieve the setting of the temperature in the test cavity 101. Combined with the heating jacket and the heat preservation jacket, the heating temperature is made more accurate; when the temperature in the test cavity 101 reaches the experimental target temperature, pressurized liquid is introduced through the pressurization inlet to apply confining pressure to the rock sample 4, so that the rock sample 4 is in a high-temperature and high-confining-pressure environment. The loading piston rod 2 is used to apply axial pressure to the rock sample 4, so that the rock sample is in a high-temperature and high-pressure environment; the combined measurement system 3 is used to measure the resistivity, permeability, and strain conditions of the rock sample 4; in summary, a high-temperature and high-pressure electro-osmotic-force combined measurement test device of the present invention realizes the simultaneous measurement of the resistivity, permeability, and strain conditions of rocks in a high-temperature and high-pressure environment.

[0033] In some possible implementation manners, the combined measurement system 3 includes: a first electrical insulating sheet 301, the upper end surface of the first electrical insulating sheet 301 abuts against the other end of the loading piston rod 2; an upper pressing head 302, the upper end surface of the upper pressing head 302 abuts against the lower end surface of the first electrical insulating sheet 301, and the lower end surface of the upper pressing head 302 abuts against the upper end surface of the rock sample 4; a lower pressing head 303, the upper end surface of the lower pressing head 303 abuts against the lower end surface of the rock sample 4; a second electrical insulating sheet 304, the upper end surface of the second electrical insulating sheet 304 abuts against the lower end surface of the lower pressing head 303, and the lower end surface of the second electrical insulating sheet 304 is in contact connection with the bottom of the test cavity 101.

[0034] Specifically, both the first electrical insulating sheet and the second electrical insulating sheet are high-temperature-resistant aluminum oxide electrical insulating sheets, which isolate the upper pressing head from the loading piston and the lower pressing head from the test chamber respectively, so as to avoid affecting the measurement of resistivity.

[0035] In some possible implementation manners, an upper electrode insertion opening is formed on one side of the upper pressing head 302, an upper seepage channel 305 penetrating through the upper pressing head 302 is formed inside the upper pressing head 302, one end of the upper seepage channel 305 is located on the other side of the upper pressing head 302, and the other end of the upper seepage channel 305 is located on the lower end surface of the upper pressing head 302; a lower electrode insertion opening is formed on one side of the lower pressing head 303, a lower seepage channel 306 penetrating through the lower pressing head 303 is formed inside the lower pressing head 303, one end of the lower seepage channel 306 is located on the other side of the lower pressing head 303, and the other end of the lower seepage channel 306 is located on the upper end surface of the lower pressing head 303.

[0036] Specifically, both the upper pressing head and the lower pressing head are made of conductive materials; the inner walls of the upper seepage channel and the lower seepage channel are both sealed with insulating materials to insulate the inside of the upper seepage channel and the inside of the lower seepage channel respectively, so as to avoid affecting the measurement of the resistivity.

[0037] In some possible implementation manners, the combined measurement system further includes an electrode assembly, and the electrode assembly includes: an upper electrode 307 disposed in the upper electrode insertion opening; an upper wire, one end of which is connected to the upper electrode 307; a lower electrode 308 disposed in the lower electrode insertion opening; a lower wire, one end of which is connected to the lower electrode 308; wherein, two aviation plugs are provided at the bottom of the test chamber 1, and the other ends of the upper wire and the lower wire are respectively connected to a corresponding one of the aviation plugs.

[0038] Specifically, the connecting wires connecting the upper electrode and the lower electrode outside the aviation plugs are both connected to an impedance analyzer to measure the resistivity of the rock sample.

[0039] In some possible implementation manners, the combined measurement system 3 further includes a seepage component, and the seepage component includes: an upper seepage sealing joint 309, one end of the upper seepage sealing joint 309 is hermetically connected to one end of the upper seepage channel 305; an upper seepage pipeline, one end of the upper seepage pipeline is hermetically connected to the other end of the upper seepage sealing joint; a lower seepage sealing joint 310, one end of the lower seepage sealing joint 310 is hermetically connected to one end of the lower seepage channel 306; a lower seepage pipeline, one end of the lower seepage pipeline is hermetically connected to the other end of the lower seepage sealing joint; wherein, a seepage inlet channel and a seepage outlet channel are further arranged at the bottom of the test chamber 1, the other end of the upper seepage pipeline passes through the seepage outlet channel and is connected to an upper pore pressure pump, and the other end of the lower seepage pipeline passes through the seepage inlet channel and is connected to a lower pore pressure pump; the upper seepage pipeline and the lower seepage pipeline are respectively hermetically and insulatingly connected to the seepage outlet channel and the seepage inlet channel.

[0040] Specifically, the upper seepage sealing joint, the upper seepage pipeline, the lower seepage sealing joint and the lower seepage pipeline are all made of insulating materials to avoid affecting the measurement of resistivity; the permeability test can be carried out by means of the steady-state method or the transient method. During the process of testing the permeability, under the action of the upper pore pressure pump and the lower pore pressure pump, liquid / gas pressure is injected into the lower seepage pipeline, and successively passes through the lower seepage sealing joint, the lower seepage channel, the rock sample, the upper seepage channel, the upper seepage sealing joint, the upper seepage pipeline and the lower pore pressure pump and flows out. Parameters such as the pore pressure and flow rate of the inflow and outflow can be obtained through the upper pore pressure pump and the lower pore pressure pump, so as to obtain the permeability of the rock sample.

[0041] In some possible implementation manners, the combined measurement system 3 further includes a silicone rubber sleeve 311. One end of the silicone rubber sleeve 311 is sleeved on the lower periphery of the upper platen 302, and the other end of the silicone rubber sleeve 311 is sleeved on the upper periphery of the lower platen 303, so that the silicone rubber sleeve 311 is sleeved on the periphery of the rock specimen 4. The upper platen 302 and the lower platen 303 are both hermetically connected to the silicone rubber sleeve 311. The combined measurement system 3 further includes a strain assembly, and the strain assembly is located inside the silicone rubber sleeve 311. The strain assembly includes: two groups of strain measuring elements. Both groups of strain measuring elements are fixed on the side surface of the rock specimen 4. One group of strain measuring elements is arranged along the axial direction of the rock specimen 4, and the other group of strain measuring elements is arranged along the circumferential direction of the rock specimen 4. Each group of strain measuring elements includes two strain gauges 312, and the two strain gauges 312 in each group are arranged in parallel. Wherein, the side of the silicone rubber sleeve 311 has a plurality of silicone rubber protrusions, and strain wire outlets 001 are opened in any two of the silicone rubber protrusions located on the side surface of the rock specimen 4, so that the wires of each group of strain gauges 312 pass through the corresponding strain wire outlets 001, and the wires of each group of strain gauges 312 are hermetically connected to the strain wire outlets 001.

[0042] Specifically, through a customized mold, a silicone rubber sleeve that conforms to the size of the rock specimen and has protrusions is processed. The function of the silicone rubber sleeve is to isolate the rock specimen from the pressurized liquid. The silicone rubber sleeve has heat shrinkage. The silicone rubber protrusions on the silicone rubber sleeve can prevent the sealing failure caused by the continuous shrinkage of the silicone rubber sleeve under high-temperature conditions. At the same time, strain wire outlets are opened in two silicone rubber protrusions. In the case of leading out the wires of the strain gauges, the strain wire outlets can be further compacted under high pressure to achieve the purpose that the higher the confining pressure, the better the sealing effect, and further hermetically connect the wires of the strain gauges 312 to the strain wire outlets 001. The function of the strain gauges is to test the strain condition of the rock specimen. One group of strain gauges is arranged axially and circumferentially respectively, and the measured strain values are averaged.

[0043] Embodiment 2

[0044] As Figures 1 to 4As shown in the figure, Embodiment 2 of the present invention provides a method for using a high-temperature and high-pressure electro-osmotic-force combined measurement test device for the use of the high-temperature and high-pressure electro-osmotic-force combined measurement test device described in Embodiment 1. The method includes: without installing a rock sample in the test cavity, performing high-temperature and high-pressure calibration on the inherent resistance of the upper electrode and the lower electrode; mounting the strain component on the rock sample, then installing it in the test cavity, turning on strain measurement, and then heating and pressurizing the inside of the test cavity so that the temperature and pressure inside the test cavity both reach the test parameters. Then, apply pore pressure to the upper seepage seal joint and the lower seepage seal joint respectively through the upper pore pressure pump and the lower pore pressure pump. After the pore pressure of the upper seepage seal joint and the pore pressure of the lower seepage seal joint are stable, measure the resistivity and permeability respectively; then apply axial pressure to the rock sample and test the resistivity and permeability; the step of applying axial pressure to the rock sample and testing the resistivity and permeability specifically includes: applying axial pressure until the rock sample yields or fractures, and then testing the resistivity and permeability; or, applying axial pressure to the rock sample in stages and testing the resistivity and permeability under each stage of axial pressure condition.

[0045] Specifically, before testing the rock specimen, the inherent resistance of the electrodes of the high-temperature and high-pressure electro-osmotic-force combined measurement test device of the present invention is calibrated at high temperature and high pressure without placing the rock specimen, that is, the temperature in the test cavity is heated to the experimental target temperature, the experimental target confining pressure is applied, so that the test cavity reaches the experimental target high-temperature and high-confining pressure environment. In this environment, the resistance of the electrodes at different frequencies is measured through the electrode assembly to perform reduction according to this calibration data during the test; during the test, after the rock specimen is installed in the test cavity, strain measurement is started, and the strain gauge records the strain information of the rock specimen during the whole process of being heated, under confining pressure, and axial pressure, that is, the mechanical properties of the rock specimen are measured; the temperature in the test cavity is heated to the experimental target temperature, the experimental target confining pressure is applied, so that the test cavity reaches the experimental target high-temperature and high-confining pressure environment, and pore pressure is applied to the upper seepage sealing joint and the lower seepage sealing joint respectively through the upper pore pressure pump and the lower pore pressure pump. The application of pore pressure can be carried out by injecting gas or liquid; when the pore pressures measured by the upper pore pressure pump and the lower pore pressure pump are in a stable state, the resistivity and permeability are measured respectively; then axial pressure is applied to the rock specimen through the loading piston rod to make the rock specimen in a high-temperature and high-pressure environment, and the resistivity and permeability are measured; it can be seen that the use method of the high-temperature and high-pressure electro-osmotic-force combined measurement test device of the present invention realizes the simultaneous measurement of electro-osmotic-force under high-temperature and high-pressure conditions; the application of axial pressure is divided into two types. One is to directly apply axial pressure until the rock specimen yields or breaks, and then the resistivity and permeability are tested; the other is to apply axial pressure to the rock specimen in stages, and the resistivity and permeability are tested under each stage of axial pressure conditions; the measurement of permeability is calculated according to the monitoring data of the upper pore pressure pump and the lower pore pressure pump. It should be noted that the use method of the high-temperature and high-pressure electro-osmotic-force combined measurement test device in the second embodiment is used for the use of the high-temperature and high-pressure electro-osmotic-force combined measurement test device in the embodiment. Therefore, the performance principle of the use method of the high-temperature and high-pressure electro-osmotic-force combined measurement test device is not described here in detail, and the parts not described in detail can be referred to in Embodiment 1.

[0046] In some possible implementation manners, the specifically mounting the strain component on the rock specimen includes: first, leveling and polishing the side surface of the rock specimen with a high-temperature repair agent; then pasting the strain gauge on the side of the rock specimen with a high-temperature patch glue; and finally coating the surface of the pasted strain gauge with a high-temperature protective glue.

[0047] Specifically, the surface of the rock specimen is not smooth enough. If the strain gauge is directly pasted, under the confining pressure, the strain gauge will be embedded into the holes on the rock surface, resulting in inaccurate measurement. Using a high-temperature repair agent to level and polish the rock surface before pasting the strain gauge can avoid the problem of inaccurate measurement. In addition, since resistivity measurement requires saturation with brine, this repair agent is also beneficial to the insulation between the strain gauge and the rock specimen, preventing the strain gauge grids from conducting electricity with each other; applying a high-temperature protective glue on the surface of the strain gauge can prevent brine from invading the strain gauge grids and the paste points.

[0048] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative work. Therefore, all technical solutions that can be obtained by those skilled in the art in this technical field based on the concept of the present invention through logical analysis, reasoning or limited experiments on the basis of the prior art should fall within the protection scope determined by the claims.

Claims

1. A high-temperature and high-pressure electro-osmotic-force combined measurement test device, characterized in that, The high-temperature and high-pressure electro-osmosis-force combined measurement test device includes: A test chamber (1), inside which a test cavity (101) is provided. The test cavity (101) has a cylindrical structure. At the bottom of the test chamber (1), a piston port (102) is provided, and the piston port (102) communicates with the test cavity (101). A loading piston rod (2), one end of which is connected to an axial pressure loader, and the other end of the loading piston rod (2) passes through the piston port (102) and is located inside the test cavity (101). A combined measurement system (3), which is located inside the test cavity (101). One end of the combined measurement system (3) abuts against the other end of the loading piston rod (2), and the other end of the combined measurement assembly (3) is in contact connection with the bottom of the test cavity (101). A rock specimen (4) is placed inside the combined measurement system (3) to measure the resistivity, permeability, and strain of the rock specimen (4).

2. The high-temperature and high-pressure electro-osmotic-force combined measurement test device according to claim 1, characterized in that, The combined measurement system (3) includes: A first electrical insulation sheet (301), the upper end surface of which abuts against the other end of the loading piston rod (2). An upper pressure head (302), the upper end surface of which abuts against the lower end surface of the first electrical insulation sheet (301), and the lower end surface of which abuts against the upper end surface of the rock specimen (4). A lower pressure head (303), the upper end surface of which abuts against the lower end surface of the rock specimen (4). A second electrical insulation sheet (304), the upper end surface of which abuts against the lower end surface of the lower pressure head (303), and the lower end surface of which is in contact connection with the bottom of the test cavity (101).

3. The high-temperature and high-pressure electro-osmotic-force combined measurement test device according to claim 2, characterized in that: On one side of the upper pressure head (302), an upper electrode insertion port is provided. Inside the upper pressure head (302), an upper seepage channel (305) that penetrates the upper pressure head (302) is provided. One end of the upper seepage channel (305) is located on the other side of the upper pressure head (302), and the other end of the upper seepage channel (305) is located on the lower end surface of the upper pressure head (302).

4. The high-temperature and high-pressure electro-osmotic-force combined measurement test device according to claim 3, characterized in that: On one side of the lower pressure head (303), a lower electrode insertion port is provided. Inside the lower pressure head (303), a lower seepage channel (306) that penetrates the lower pressure head (303) is provided. One end of the lower seepage channel (306) is located on the other side of the lower pressure head (303), and the other end of the lower seepage channel (306) is located on the upper end surface of the lower pressure head (303).

5. The high-temperature and high-pressure electro-osmotic-force combined measurement test device according to claim 4, characterized in that, The combined measurement system further includes an electrode assembly, and the electrode assembly includes: An upper electrode (307), which is arranged inside the upper electrode insertion port. An upper wire, one end of which is connected to the upper electrode (307). A lower electrode (308), which is arranged inside the lower electrode insertion port. A lower wire, one end of which is connected to the lower electrode (308). Among them, two aviation plugs are arranged at the bottom of the test chamber (1), and the other ends of the upper wire and the lower wire are respectively connected to one of the corresponding aviation plugs.

6. The high-temperature and high-pressure electro-osmotic-force combined measurement test device according to claim 5, characterized in that, The combined measurement system (3) further includes a seepage component, and the seepage component includes: an upper seepage sealing joint (309), one end of the upper seepage sealing joint (309) is hermetically connected to one end of the upper seepage channel (305); an upper seepage pipeline, one end of the upper seepage pipeline is hermetically connected to the other end of the upper seepage sealing joint; a lower seepage sealing joint (310), one end of the lower seepage sealing joint (310) is hermetically connected to one end of the lower seepage channel (306); a lower seepage pipeline, one end of the lower seepage pipeline is hermetically connected to the other end of the lower seepage sealing joint (310); Among them, a seepage inlet channel and a seepage outlet channel are further arranged at the bottom of the test chamber (1), the other end of the upper seepage pipeline passes through the seepage outlet channel and is connected to an upper pore pressure pump, and the other end of the lower seepage pipeline passes through the seepage inlet channel and is connected to a lower pore pressure pump; the upper seepage pipeline and the lower seepage pipeline are respectively hermetically and insulatingly connected to the seepage outlet channel and the seepage inlet channel.

7. An apparatus for jointly measuring high-temperature and high-pressure electro-osmosis and force according to claim 6, characterized in that: The combined measurement system (3) further includes a silicone rubber sleeve (311), one end of the silicone rubber sleeve (311) is sleeved on the outer periphery of the lower part of the upper platen (302), and the other end of the silicone rubber sleeve (311) is sleeved on the outer periphery of the upper part of the lower platen (303), so that the silicone rubber sleeve (311) is sleeved on the outer periphery of the rock specimen (4); the upper platen (302) and the lower platen (303) are both hermetically connected to the silicone rubber sleeve (311).

8. The high-temperature and high-pressure electro-osmotic-force combined measurement test device according to claim 7, characterized in that, The combined measurement system (3) further includes a strain component, the strain component is located inside the silicone rubber sleeve (311), and the strain component includes: two groups of strain measuring parts, both groups of strain measuring parts are fixed on the side surface of the rock specimen (4), one group of strain measuring parts is arranged along the axial direction of the rock specimen (4), and the other group of strain measuring parts is arranged along the circumferential direction of the rock specimen (4); each group of strain measuring parts includes two strain gauges (312), and the two strain gauges (312) in each group are arranged in parallel; Among them, the side of the silicone rubber sleeve (311) has a number of silicone rubber protrusions, and strain wire outlets (001) are opened in any two of the silicone rubber protrusions located on the side surface of the rock specimen (4), so that the wires of each group of strain gauges (312) pass through the corresponding strain wire outlets (001), and the wires of each group of strain gauges (312) are hermetically connected to the strain wire outlets (001).

9. A method for using a test device for combined measurement of high-temperature and high-pressure electro-osmotic force, characterized in that, For the use of a high-temperature and high-pressure electro-osmosis-force combined measurement test device according to any one of claims 1 to 8, the use method includes: Without installing a rock specimen in the test cavity, calibrating the inherent resistance of the upper electrode and the lower electrode under high temperature and high pressure; Install the strain components on the rock specimen, then install it in the test cavity, turn on the strain measurement, and then heat and pressurize the inside of the test cavity so that the temperature and pressure inside the test cavity reach the test parameters. Then apply pore pressure to the upper seepage seal joint and the lower seepage seal joint respectively through the upper pore pressure pump and the lower pore pressure pump. After the pore pressure of the upper seepage seal joint and the pore pressure of the lower seepage seal joint are stable, measure the resistivity and permeability respectively; Then apply axial pressure to the rock specimen and test the resistivity and permeability; The applying axial pressure to the rock specimen and testing the resistivity and permeability specifically include: Apply axial pressure until the rock specimen yields or fractures, and then test the resistivity and permeability; Or, Apply axial pressure to the rock specimen in stages and test the resistivity and permeability under each stage of axial pressure condition.

10. The usage method of a high-temperature and high-pressure electro-osmosis-force combined measurement test device according to claim 9, characterized in that, The installing the strain components on the rock specimen specifically includes: First, level and polish the side of the rock specimen with high-temperature repair agent; Then paste the strain gauges on the side of the rock specimen with high-temperature patch glue; Finally, coat the surface of the pasted strain gauges with high-temperature protective glue.

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