Portable apparatus and method for detecting the apparent specific gravity of ring knife soil samples using gamma rays

Abstract

This invention discloses a portable device and method for detecting the bulk density of a ring knife soil sample using gamma rays, and belongs to the field of soil bulk density measuring devices. The device includes a gamma ray source, a housing, a radiation particle counter, a pull-out sample case, and a power supply. The center of the radiation detection window of the radiation particle counter is on the same vertical line as the center of a third radiation penetration hole opened in the top plate of the sample case, a second radiation penetration hole opened in the bottom plate of the pull-out sample case, a first radiation penetration hole opened in the sample case support plate, and the gamma ray emission hole. The radiation particle counter records the gamma ray intensity before and after placing the soil sample, and then the bulk density of the soil sample is obtained by direct calculation based on the soil bulk density calculation formula. This method allows for rapid calculation of soil bulk density data, enabling continuous and rapid measurement of the bulk density of ring knife soil samples in the field.

Claims

1. A portable device that uses gamma rays to detect the apparent specific gravity of a ring knife soil sample. It includes a gamma-ray source (1), a housing (2), a radiation particle counter (11), a pull-out sample case (8), and a power supply. The housing (2) has a hollow structure, and the following are installed inside the housing (2) from bottom to top: a gamma ray source (1), a sample case support plate (6), a pull-out sample case (8) for placing soil samples, a sample case top plate (9), and a radiation particle counter (11). The bottom of the pull-out sample case (8) is provided with a slide rail (802), and the slide rail (802) forms a sliding connection with the sample case support plate (6). Inside the aforementioned pull-out sample case (8), there is a ring knife case fixing ring (801) for securing soil samples. The top of the gamma-ray source (1) is a gamma-ray emission port (3), A first radiation penetration hole (4) is provided in the sample case support plate (6), a second radiation penetration hole (5) is provided in the bottom plate of the drawer-type sample case (8), and a third radiation penetration hole (10) is provided in the top plate (9) of the sample case. The center of the radiation detection window of the radiation particle counter (11) lies on the same vertical line as the centers of the third radiation penetration hole (10), the second radiation penetration hole (5), the first radiation penetration hole (4), and the gamma-ray emission hole (3). The power supply lines of the aforementioned power source are connected to the gamma ray source (1) and the radiation particle counter (11), respectively, to provide power. A portable device for detecting the apparent specific gravity of a ring knife soil sample using gamma rays, characterized in that a universal caster (14) is installed on the bottom of the housing (2) by a caster support (13).

2. A portable device for detecting the apparent specific gravity of a ring knife soil sample using gamma rays, characterized in that the gamma ray source (1) is a portable single-energy gamma ray source, as described in claim 1.

3. A portable device for detecting the apparent specific gravity of a ring knife soil sample using gamma rays, characterized in that the housing (2) is provided with a handle (12) on top for easy handling, as described in claim 1.

4. A portable device for detecting the apparent specific gravity of a ring knife soil sample using gamma rays, characterized in that a handle (7) is provided on the front side of the pull-out type sample case (8) to facilitate pulling it out.

5. A portable device for detecting the apparent specific gravity of a ring knife soil sample using gamma rays, as described in claim 1, characterized in that the power source is a rechargeable lithium-ion battery and the power source is provided with a switch.

6. A portable device for detecting the apparent specific gravity of a ring knife soil sample using gamma rays, as described in claim 1, characterized in that there are four of each of the caster support members (13) and universal casters (14), and these are installed at the four corners of the bottom of the housing (2).

7. A method for detecting the apparent specific gravity of a ring knife soil sample using a portable device according to any one of claims 1 to 6, The following steps, S1: Pull out the pull-out sample case (8), attach the aluminum ring knife case lid and ring knife case bottom corresponding to each end of the ring knife to assemble the complete ring knife case, then fix the ring knife case into the ring knife case fixing ring (801) of the pull-out sample case (8), ensuring that the center position of the bottom of the ring knife case coincides with the center position of the second radiation through hole (5) of the bottom plate of the pull-out sample case (8), push the pull-out sample case (8) back into the box body (2), so that the centers of the bottom of the ring knife case, the second radiation through hole (5), and the first radiation through hole (4) are located on the same vertical line. S2: Turn on the power, activate the gamma ray source (1) to emit gamma rays, start counting with the radiation particle counter (11), and measure the gamma ray intensity I after it has passed through the ring knife case which is not filled with soil sample. Ａｌ Obtain, S3: The aluminum ring knife case lid and ring knife case bottom are attached to both ends of the ring knife used to collect the soil sample, and then this is fixed into the ring knife case fixing ring (801) of the pull-out sample case (8). Processes S1 and S2 are repeated to obtain the gamma ray intensity I after passing through the ring knife case filled with soil sample. S4: I obtained in process S2 Ａｌ Substitute I, obtained in process S3, into the soil bulk density calculation formula to determine the bulk density of the soil sample. A method characterized by comprising the following:

8. The formula for calculating the bulk density of soil is as follows: During the ceremony, I 0 This is the initial gamma ray intensity (unit: Bq) emitted by the gamma ray source. I Ａｌ This is the gamma ray intensity (unit: Bq) after passing through a ring knife case that does not contain a soil sample. I represents the gamma ray intensity (unit: Bq) after passing through the ring knife case containing the soil sample. μ Ａｌ This is the gamma-ray mass attenuation coefficient of metallic aluminum (unit: cm). 2 / g) and ρ Ａｌ The density of metallic aluminum (unit: g / cm³) 3 ) and L Ａｌ is the height of the entire ring knife case (unit: cm), ρ ｗ The density of water (unit: g / cm³) 3 ) and L is the height of the soil sample inside the ring knife case (in cm). μ ｓ This is the gamma-ray mass attenuation coefficient of soil (unit: cm). 2 / g) is, A method for detecting the apparent specific gravity of a ring knife soil sample according to claim 7, characterized in that it is the method described in claim 7.

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