Device and method for measuring porosity of dry gravel in box based on ideal gas method

Abstract

The invention provides a device and a method for measuring the porosity of dry gravel in a box based on an ideal gas method, and relates to the technical field of porosity measurement of a gravel model test. The device comprises an air compressor, and the air compressor is connected with an air delivery pipe; a first barometer is arranged at the top of the gas collection tank; a gas conveying valve is arranged at the bottom of the gas collection tank; a bottom plate of the gas collection tank is connected with a gas injection cylinder; the upper part of the gas injection cylinder is aligned with and connected with the gas conveying valve; a sealing box cavity is formed below the sealing box upper top plate, a sealing box lower bottom plate is arranged below the sealing box cavity, and exhaust holes are formed in the sealing box lower bottom plate. According to the invention, the porosity of the sandstone can be accurately and rapidly measured in the model box, and the problem that the result is inconsistent with the actual result due to the fact that the sandstone sample is independently moved from the model box to other places for measurement is avoided.

Description

Technical Field

[0001] This application relates to the field of porosity determination technology in sand and gravel model tests, and in particular to a device and method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method. Background Technology

[0002] Sand and gravel model testing is a widely used geotechnical test. Traditional methods for determining sand and gravel porosity, such as the water saturation method, gas adsorption method, and density method, suffer from drawbacks such as cumbersome operation and high time consumption. The water saturation method requires complete immersion of the sample and ensures that water penetrates into the pores, making it susceptible to air bubbles and leading to unstable measurements. While the gas adsorption method offers high accuracy, it requires expensive equipment and is less efficient for large-particle sand and gravel. Traditional methods are subject to strict experimental conditions; changes in environmental factors such as temperature and humidity can affect the measurement results. Furthermore, these methods depend on sample morphology; inhomogeneous particle size and pore structure can easily introduce errors. Therefore, traditional methods have low accuracy and reliability, and limited applicability to special sand and gravel samples, failing to meet the needs of rapid, large-scale experiments. To date, no method has been developed that can directly determine the porosity of sand and gravel within a model chamber. Summary of the Invention

[0003] This application provides a device and method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method. This enables accurate and rapid determination of the porosity of sand and gravel in a test chamber, solving the problems of traditional methods, such as the water saturation method, which require complex pretreatment or immersion processes, and suffer from bubble interference and measurement instability. The device and method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method are independent of sample morphology, avoiding errors caused by uneven particle size and pore distribution. Furthermore, the measurement process is simple and rapid, has low requirements for environmental conditions, and is unaffected by changes in temperature and humidity, providing higher accuracy and reliability. In summary, the device and method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method have advantages such as simple operation, high accuracy, and wide applicability, ensuring accurate porosity parameters for sand and gravel model experiments.

[0004] In a first aspect, this application provides a device for measuring the porosity of dry sand and gravel in a chamber based on the ideal gas method, comprising an air compressor connected to an air supply pipe; the air supply pipe connected to an air supply valve located at the top of a gas collection box; a first pressure gauge installed at the top of the gas collection box; an air supply valve installed at the bottom of the gas collection box; an injection cylinder connected to the bottom plate of the gas collection box; an upper part of the injection cylinder aligned with and connected to the air supply valve; a second pressure gauge installed on the side of the injection cylinder; a top plate of a sealed box connected to the lower part of the injection cylinder; a cavity below the top plate of the sealed box; a bottom plate below the cavity; an exhaust port on the bottom plate; the top plate, the cavity, and the bottom plate together forming a sealed box; the sealed box is seamlessly inserted into the side wall of the model box; and a depth gauge is installed on the inner wall of the model box.

[0005] Preferably, the gas collection box is equipped with a gas supply valve and a gas delivery valve, through which gas exchange occurs with the interior of the model box.

[0006] Preferably, the upper part of the gas injection cylinder is sealed and aligned with the gas delivery valve to inject gas from the gas collection box into the sealed cavity.

[0007] Preferably, the sealed box includes a top plate, a cavity, and a bottom plate. The bottom plate is provided with an exhaust port to deliver gas from the air injection cylinder into the model box.

[0008] Secondly, this application provides a method for determining the porosity of dry sand and gravel in a chamber based on the ideal gas method, using the apparatus described above, and including the following steps:

[0009] S1. Establish a symbol for the method of determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method;

[0010] S2. Determine the operating steps;

[0011] S3. Derive the core algorithm for determining the porosity of dry sand and gravel in a chamber based on the ideal gas method;

[0012] S4. Establish the calibration equation and calibration coefficients for the determination of porosity of dry sand and gravel in a test chamber based on the ideal gas method;

[0013] S5. Determine the calibration steps;

[0014] S6. Based on the operating steps determined in S2, formally determine the porosity of dry sand and gravel;

[0015] S7. Calculate the porosity of dry sand and gravel in the chamber based on the ideal gas method.

[0016] Preferably, step S1 includes the following steps:

[0017] S11. Let the volume of the gas collection box be V. a ;

[0018] S12. The volume of the gas cylinder is V. b ;

[0019] S13. Let the volume inside the sealed box be V. c ;

[0020] S14. Let the length of the model box be a and the width be b;

[0021] S15. Let the atmospheric pressure be P0.

[0022] 7. The method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method as described in claim 5, characterized in that step S2 includes the following steps:

[0023] S21. Assemble a chamber dry sand and gravel porosity measuring device based on the ideal gas method;

[0024] S22. Close the gas supply valve, supply gas to the gas collection box through the air compressor, and measure the gas pressure P1 in the gas collection box after the gas supply is completed by the first pressure gauge.

[0025] S23. Fill the model box with sand and gravel in layers and level it;

[0026] S24. The vertical lifting device for measuring the porosity of dry sand and gravel in a box based on the ideal gas method is used to make the bottom plate of the sealed box contact the upper surface of the sand and gravel.

[0027] S25. Record the height l of the bottom plate of the model box inside the model box at this time;

[0028] S26. Close the air supply valve and open the air supply valve to make the air pressure reach equilibrium in the air collection box, air injection cylinder, sealing box and model box. Record the air pressure P2 after equilibrium.

[0029] S27. Record the atmospheric pressure at this time as P0.

[0030] Preferably, step S5 includes the following steps:

[0031] S51. Assemble the apparatus for measuring the porosity of dry sand and gravel in a chamber based on the ideal gas method;

[0032] S52. Close the gas supply valve, supply gas to the gas collection box through the air compressor, and measure the gas pressure P in the gas collection box after the gas supply is completed using the first pressure gauge. 11 ;

[0033] S52, The vertical lifting device for measuring the porosity of dry sand and gravel in a box based on the ideal gas method is used to make the bottom plate of the sealed box contact the bottom of the model box.

[0034] S53. Close the air supply valve and open the air supply valve again to allow the air pressure to reach equilibrium in the air collection box, air injection cylinder, and sealing box. Record the equilibrium air pressure P. 12 ;

[0035] S54. Remove the dry sand and gravel porosity measuring device based on the ideal gas method from the model box and release all the gas;

[0036] S55. Close the gas supply valve, supply air to the air collection box through the air compressor, and measure the air pressure P in the air collection box after the gas supply is completed using the first pressure gauge. 21 ;

[0037] S56. The vertical lifting device for measuring the porosity of dry sand and gravel in a box based on the ideal gas method is used to make the bottom plate of the sealed box contact the top of the model box, and the height of the model box is recorded as L.

[0038] S57. Close the air supply valve and open the air supply valve again to allow the air pressure to reach equilibrium in the air collection box, air injection cylinder, sealing box, and model box. Record the equilibrium air pressure P. 22 ;

[0039] S58. Record the atmospheric pressure as P0;

[0040] S59. Establish a set of calibration equations for the determination of porosity of dry sand and gravel in a test chamber based on the ideal gas method.

[0041]

[0042] S510. Solve the calibration equations for the method of determining the porosity of dry sand and gravel in a chamber based on the ideal gas method; obtain the percentage of volume constant A and the percentage of volume coefficient B.

[0043] Preferably, in step S3, the core algorithm for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method is expressed as follows:

[0044]

[0045] In step S4, the calibration equation and calibration coefficients for the determination of porosity of dry sand and gravel in a test chamber based on the ideal gas method are established, expressed as follows:

[0046]

[0047] in, A represents the percentage of the volume constant, and B represents the percentage of the volume coefficient.

[0048] In S7, the porosity of dry sand and gravel in the chamber based on the ideal gas method is calculated using the following formula:

[0049]

[0050] Where n is the porosity of dry sand and gravel.

[0051] Preferably, the indoor temperature is kept constant during calibration and formal measurement, and the temperatures inside the gas collection box, gas injection cylinder, sealed box and model box are kept at the same temperature.

[0052] This application provides a device and method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method, relating to the field of sand and gravel model testing. It provides a direct detection device and method for the porosity of sand and gravel in a test chamber, utilizing compressed air to fill the pores of dry sand and gravel, enabling accurate measurement of porosity within the test chamber. This overcomes the drawbacks of traditional methods, eliminating the need for complex pretreatment or immersion, and avoiding bubble interference and morphology dependence. The measurement process is simple, fast, and highly accurate, unaffected by environmental conditions, and possesses better reliability and applicability. Attached Figure Description

[0053] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0054] Figure 1 A schematic diagram showing the connection between a device for measuring the porosity of dry sand and gravel in a chamber based on the ideal gas method and a model chamber, provided for an embodiment of this application;

[0055] Figure 2 A schematic diagram of a device for measuring the porosity of dry sand and gravel in a chamber based on the ideal gas method provided in this application embodiment;

[0056] Figure 3 A flowchart illustrating a method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method, provided in this application embodiment.

[0057] Explanation of reference numerals in the attached figures:

[0058] 1. Air compressor; 2. Air supply pipe; 3. First pressure gauge; 4. Air supply valve; 5. Air collection box; 6. Air supply valve; 7. Air injection cylinder; 8. Second pressure gauge; 9. Sealed top plate; 10. Sealed bottom plate; 11. Sealed box cavity; 12. Model box; 13. Depth caliper.

[0059] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0060] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0061] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0062] This application provides a device for determining the porosity of dry sand and gravel in a chamber based on the ideal gas method, such as... Figures 1 to 3 As shown, the device includes an air compressor 1 connected to an air supply pipe 2; the air supply pipe 1 is connected to an air supply valve 4, the air supply valve 4 is located at the top of an air collection box 5, a first pressure gauge 3 is installed at the top of the air collection box 5, an air supply valve 6 is installed at the bottom of the air collection box 5, an air injection cylinder 7 is connected to the bottom plate of the air collection box 5, the upper part of the air injection cylinder 7 is aligned with and connected to the air supply valve 6, a second pressure gauge 8 is installed on the side of the air injection cylinder 7, the lower part of the air injection cylinder 7 is connected to the upper top plate 9 of the sealing box, a sealing box cavity 11 is located below the upper top plate 9 of the sealing box, a sealing box lower bottom plate 10 is located below the sealing box cavity 11, and an exhaust hole is provided on the lower bottom plate of the sealing box. The upper top plate 9 of the sealing box, the sealing box cavity 11, and the sealing box lower bottom plate 10 together form a sealing box. The sealing box can be seamlessly inserted into the model box 12 along the side wall of the model box. A depth gauge 13 is provided on the inner wall of the model box.

[0063] It should be noted that, for reference Figure 1 and Figure 2 In this embodiment, the gas collection box 5 is equipped with a gas supply valve 4 and a gas delivery valve 5, which can exchange gases with the inside of the model box 12 through the gas supply valve 4 and the gas delivery valve 5.

[0064] In some embodiments, see Figure 1 and Figure 2 The upper part of the air injection cylinder 7 is sealed and aligned with the air supply valve 6, which can inject gas from the gas collection box 5 into the sealed cavity 11.

[0065] In some embodiments, see Figure 1 and Figure 2The sealed box consists of a top plate 9, a cavity 11, and a bottom plate 10. The bottom plate 10 is provided with an exhaust hole, which can deliver gas from the air injection cylinder 7 into the model box 12.

[0066] This application also provides a method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method, see reference. Figure 3 The process includes steps S1 to S7, which are detailed below.

[0067] S1. Establish a symbol for the method of determining the porosity of dry sand and gravel in a chamber based on the ideal gas method.

[0068] In some embodiments, step S1 includes the following sub-steps:

[0069] S11. Let the volume of the gas collection box be V. a ;

[0070] S12. The volume of the gas cylinder is V. b ;

[0071] S13. Let the volume inside the sealed box be V. c ;

[0072] S14. Let the length of the model box be a and the width be b;

[0073] S15. Let the atmospheric pressure be P0.

[0074] S2. Outline the operational steps of the method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method.

[0075] In some embodiments, step S2 includes the following sub-steps:

[0076] S21. Assemble the apparatus for determining the porosity of dry sand and gravel in a box based on the ideal gas method according to claim 1;

[0077] S22. Close the gas supply valve, supply gas to the gas collection box through the air compressor, and measure the gas pressure P1 in the gas collection box after the gas supply is completed by the first pressure gauge.

[0078] S23. Fill the model box with sand and gravel in layers and level it;

[0079] S24. The vertical lifting device for measuring the porosity of dry sand and gravel in a box based on the ideal gas method is used to make the bottom plate of the sealed box contact the upper surface of the sand and gravel.

[0080] S25. Record the height l of the bottom plate of the model box inside the model box at this time;

[0081] S26. Close the air supply valve and open the air supply valve to make the air pressure reach equilibrium in the air collection box, air injection cylinder, sealing box and model box. Record the air pressure P2 after equilibrium.

[0082] S27. Record the atmospheric pressure at this time as P0.

[0083] S3. The core algorithm for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method is derived as follows:

[0084]

[0085] S4. Establish the calibration equation and calibration coefficients for the determination of porosity of dry sand and gravel in a test chamber based on the ideal gas method, expressed as follows:

[0086]

[0087] in, A is called the percentage of the volume constant, and B is called the percentage of the volume coefficient.

[0088] S5. Outline the calibration steps for the method of determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method.

[0089] In some embodiments, step S5 includes the following sub-steps:

[0090] S51. Assemble the apparatus for measuring the porosity of dry sand and gravel in a chamber based on the ideal gas method;

[0091] S52. Close the gas supply valve, supply gas to the gas collection box through the air compressor, and measure the gas pressure P in the gas collection box after the gas supply is completed using the first pressure gauge. 11 ;

[0092] S52, The vertical lifting device for measuring the porosity of dry sand and gravel in a box based on the ideal gas method is used to make the bottom plate of the sealed box contact the bottom of the model box.

[0093] S53. Close the air supply valve and open the air supply valve again to allow the air pressure to reach equilibrium in the air collection box, air injection cylinder, and sealing box. Record the equilibrium air pressure P. 12 ;

[0094] S54. Remove the dry sand and gravel porosity measuring device based on the ideal gas method from the model box and release all the gas;

[0095] S55. Close the gas supply valve, supply air to the air collection box through the air compressor, and measure the air pressure P in the air collection box after the gas supply is completed using the first pressure gauge. 21 ;

[0096] S56. The vertical lifting device for measuring the porosity of dry sand and gravel in a box based on the ideal gas method is used to make the bottom plate of the sealed box contact the top of the model box, and the height of the model box is recorded as L.

[0097] S57. Close the air supply valve and open the air supply valve again to allow the air pressure to reach equilibrium in the air collection box, air injection cylinder, sealing box, and model box. Record the equilibrium air pressure P. 22 ;

[0098] S58. Record the atmospheric pressure as P0;

[0099] S59. Establish a set of calibration equations for the determination of porosity of dry sand and gravel in a test chamber based on the ideal gas method.

[0100]

[0101] S510. Solve the calibration equations for the method of determining the porosity of dry sand and gravel in a chamber based on the ideal gas method; obtain the percentage of volume constant A and the percentage of volume coefficient B.

[0102] S6. Determine the porosity of dry sand and gravel according to the operating steps in S2.

[0103] S7. Calculate the porosity of dry sand and gravel in the test chamber based on the ideal gas method. The calculation formula is as follows:

[0104]

[0105] Where n is the porosity of dry sand and gravel.

[0106] The various embodiments or implementation methods described in this specification are presented in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referred to each other.

[0107] It should be noted that the terms "one embodiment," "embodiment," "exemplary embodiment," "some embodiments," etc., mentioned in the specification indicate that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Moreover, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments, whether explicitly described or not, is within the knowledge scope of those skilled in the art.

[0108] Generally speaking, terms should be understood at least in part by their use in context. For example, at least in part by context, the term "one or more" as used in the text can be used to describe any feature, structure, or characteristic of the singular meaning, or a combination of features, structures, or characteristics of the plural meaning. Similarly, at least in part by context, terms such as "a" or "the" can also be understood to convey either singular or plural usage.

[0109] It should be readily understood that the terms “on,” “above,” and “on top of” in this disclosure should be interpreted in the broadest possible sense, such that “on” means not only “directly on something” but also “on something” with an intermediate feature or layer therebetween, and that “above” or “on top of” means not only “on top of something” but also “on top of something” without an intermediate feature or layer therebetween (i.e., directly on something).

[0110] Furthermore, for ease of explanation, spatially relative terms such as "below," "below," "under," "above," and "above" may be used to describe the relationship of one element or feature relative to other elements or features as shown in the figures. Spatially relative terms are intended to encompass different orientations of the device in use or operation other than those shown in the figures. The device may have other orientations (rotated 90 degrees or in other orientations), and the spatially relative descriptive terms used herein may be interpreted accordingly.

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application 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 or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A device for determining the porosity of dry sand and gravel in a chamber based on the ideal gas method, characterized in that, The system includes an air compressor connected to an air supply pipe; the air supply pipe is connected to an air delivery valve located at the top of an air collection box; a first pressure gauge is installed at the top of the air collection box; an air delivery valve is installed at the bottom of the air collection box; an air injection cylinder is connected to the bottom plate of the air collection box; the upper part of the air injection cylinder is aligned with and connected to the air delivery valve; a second pressure gauge is installed on the side of the air injection cylinder; the lower part of the air injection cylinder is connected to the upper top plate of a sealing box; a sealing box cavity is located below the upper top plate of the sealing box; a lower bottom plate of the sealing box is located below the cavity; an exhaust port is provided on the lower bottom plate of the sealing box; the upper top plate, the cavity, and the lower bottom plate together form a sealing box; the sealing box is seamlessly attached to the side wall of the model box and extends into the model box; a depth gauge is installed on the inner wall of the model box.

2. The apparatus for determining the porosity of dry sand and gravel in a chamber based on the ideal gas method as described in claim 1, characterized in that: The gas collection box is equipped with a gas supply valve and a gas delivery valve, through which gas exchange occurs between the gas collection box and the interior of the model box.

3. The apparatus for determining the porosity of dry sand and gravel in a chamber based on the ideal gas method as described in claim 1, characterized in that: The upper part of the gas injection cylinder is sealed and aligned with the gas delivery valve to inject gas from the gas collection box into the sealed cavity.

4. The apparatus for determining the porosity of dry sand and gravel in a chamber based on the ideal gas method as described in claim 1, characterized in that: The sealed box includes a top plate, a cavity, and a bottom plate. The bottom plate is provided with an exhaust port to deliver gas from the air injection cylinder into the model box.

5. A method for determining the porosity of dry sand and gravel in a chamber based on the ideal gas method, using the apparatus as described in any one of claims 1 to 4, characterized in that: Includes the following steps: S1. Establish a symbol for the method of determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method; S2. Determine the operational steps for the method of determining the porosity of dry sand and gravel in a chamber based on the ideal gas method; S3. Derive the core algorithm for determining the porosity of dry sand and gravel in a chamber based on the ideal gas method; S4. Establish the calibration equation and calibration coefficients for the determination of porosity of dry sand and gravel in a test chamber based on the ideal gas method; S5. Determine the calibration steps for the method of determining the porosity of dry sand and gravel in a chamber based on the ideal gas method; S6. Based on the operating steps determined in S2, formally determine the porosity of dry sand and gravel; S7. Calculate the porosity of dry sand and gravel in the chamber based on the ideal gas method.

6. The method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method as described in claim 5, characterized in that, Step S1 includes the following steps: S11. Let the volume of the gas collection box be V. a ; S12. The volume of the gas cylinder is V. b ; S13. Let the volume inside the sealed box be V. c ; S14. Let the length of the model box be a and the width be b; S15. Let the atmospheric pressure be P0.

7. The method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method as described in claim 5, characterized in that, Step S2 includes the following steps: S21. Assemble a chamber dry sand and gravel porosity measuring device based on the ideal gas method; S22. Close the gas supply valve, supply gas to the gas collection box through the air compressor, and measure the gas pressure P1 in the gas collection box after the gas supply is completed by the first pressure gauge. S23. Fill the model box with sand and gravel in layers and level it; S24. The vertical lifting device for measuring the porosity of dry sand and gravel in a box based on the ideal gas method is used to make the bottom plate of the sealed box contact the upper surface of the sand and gravel. S25. Record the height l of the bottom plate of the model box inside the model box at this time; S26. Close the air supply valve and open the air supply valve to make the air pressure reach equilibrium in the air collection box, air injection cylinder, sealing box and model box. Record the air pressure P2 after equilibrium. S27. Record the atmospheric pressure at this time as P0.

8. The method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method as described in claim 6, characterized in that, Step S5 includes the following steps: S51. Assemble the apparatus for measuring the porosity of dry sand and gravel in a chamber based on the ideal gas method; S52. Close the gas supply valve, supply gas to the gas collection box through the air compressor, and measure the gas pressure P in the gas collection box after the gas supply is completed using the first pressure gauge. 11 ; S52, The vertical lifting device for measuring the porosity of dry sand and gravel in a box based on the ideal gas method is used to make the bottom plate of the sealed box contact the bottom of the model box. S53. Close the air supply valve and open the air supply valve again to allow the air pressure to reach equilibrium in the air collection box, air injection cylinder, and sealing box. Record the equilibrium air pressure P. 12 ; S54. Remove the dry sand and gravel porosity measuring device based on the ideal gas method from the model box and release all the gas; S55. Close the gas supply valve, supply air to the gas collection box through the air compressor, and measure the gas pressure P in the gas collection box after the gas supply is completed using the first pressure gauge. 21 ; S56. The vertical lifting device for measuring the porosity of dry sand and gravel in a box based on the ideal gas method is used to make the bottom plate of the sealed box contact the top of the model box, and the height of the model box is recorded as L. S57. Close the air supply valve and open the air supply valve again to allow the air pressure to reach equilibrium in the air collection box, air injection cylinder, sealing box, and model box. Record the equilibrium air pressure P. 22 ; S58. Record the atmospheric pressure as P0; S59. Establish a set of calibration equations for the determination of porosity of dry sand and gravel in a test chamber based on the ideal gas method. S510. Solve the calibration equations for the method of determining the porosity of dry sand and gravel in a chamber based on the ideal gas method; obtain the percentage of volume constant A and the percentage of volume coefficient B.

9. The method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method as described in claim 6, characterized in that, In step S3, the core algorithm for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method is expressed as follows: In step S4, the calibration equation and calibration coefficients for the determination of porosity of dry sand and gravel in a test chamber based on the ideal gas method are established, expressed as follows: in, A represents the percentage of the volume constant, and B represents the percentage of the volume coefficient. In S7, the porosity of dry sand and gravel in the chamber based on the ideal gas method is calculated using the following formula: Where n is the porosity of dry sand and gravel.

10. A method for determining the porosity of dry sand and gravel in a test chamber based on the ideal gas method as described in any one of claims 5 to 9, characterized in that: During the calibration and formal measurement process, the indoor temperature was kept constant, and the temperatures inside the gas collection box, gas injection cylinder, sealed box, and model box were kept at the same level.

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