Method for making a core sample of a vadose loose rock

Abstract

The application provides a method for manufacturing a vadose loose rock core sample, and belongs to the technical field of geology and soil engineering. Through a process flow integrating surface treatment, chemical pretreatment, customized embedding and solidification, the original physical structure (such as bedding, fissure and pore), water content state and material composition of the vadose loose rock core are maximally fixed and preserved, and are converted into a solidified original sample which is firm, transparent, long-term preserved, and easy to be observed and measured from multiple angles, thereby providing high-quality basic materials for scientific research, teaching display and engineering archiving in the fields of geology and environment.

Description

Technical Field

[0001] This invention relates to the field of geology and soil engineering technology, specifically to a core specimen of loose rock in the vadose zone and its preparation method. Background Technology

[0002] In environmental geological surveys, groundwater pollution assessments, engineering geological explorations, and Quaternary geological studies, obtaining vadose zone cores through drilling is a crucial means of acquiring firsthand geological information. These vadose zone cores, especially those from aquifer zones, contain vital in-situ information on stratigraphic structure, sedimentary sequences, aquifer characteristics, and pollutant distribution.

[0003] However, due to their physical characteristics, these water-bearing rock cores face severe challenges in post-collection processing: (1) Structural fragility: The soil particles have weak cohesion and high water content, making them prone to cracking, pulverization, or structural collapse once they lose water, thus losing their original state. (2) Compositional variability: Exposure to air leads to rapid evaporation of moisture, which not only changes the physical volume and structure of the rock core but may also cause chemical changes such as precipitation of soluble salts and changes in redox state, making the sample lose its representativeness. (3) Difficulty in preservation and transportation: Traditional methods (such as simple sealing in plastic bags or iron boxes) cannot effectively fix the structure, and vibration and compression during long-distance transportation can easily cause rock core disturbance or even breakage, resulting in blurred bedding interfaces and cross-contamination of samples at different depths. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a core specimen of loose vadose zone rock and a method for its preparation. This invention enables the preparation and long-term preservation of undisturbed core specimens of water-bearing, loosely structured vadose zone rock, and can fix and preserve the original physical structure, water-bearing state, and material composition of water-bearing cores to the greatest extent.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for preparing a core specimen of loose rock in the vadose zone, comprising the following steps: The loose rock cores in the vadose zone were pretreated sequentially with hydrogen peroxide solution and quaternary ammonium salt surfactant solution to obtain pretreated rock cores; The pretreated rock core was placed in a sample box, and an embedding agent was injected using a layered injection method to cover the rock core; the embedding agent included a mixture of epoxy resin and AB glue. The core samples were statically solidified after being injected with the embedding agent to obtain loose rock core specimens in the vadose zone.

[0006] Preferably, before the pretreatment, the surface of the collected vadose zone loose rock core is cleaned.

[0007] Preferably, the mass concentration of the hydrogen peroxide solution is 3-10%; The pretreatment method of the hydrogen peroxide solution is spraying or impregnation; when spraying, the mass ratio of the rock core to the volume of the hydrogen peroxide solution is 1 kg: 50~100 mL; The hydrogen peroxide solution soaking time is 10-15 minutes.

[0008] Preferably, the quaternary ammonium salt surfactant includes one or more of dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octadecyltrimethylammonium chloride, benzalkonium chloride, dodecyl dimethylbenzylammonium chloride, octadecyl dimethylbenzylammonium chloride, and polyquaternary ammonium salts.

[0009] Preferably, the mass concentration of the quaternary ammonium salt surfactant solution is 0.1~0.5%; The pretreatment method of the quaternary ammonium salt surfactant solution is spraying or wetting; when spraying, the mass ratio of the rock core to the volume ratio of the quaternary ammonium salt surfactant solution is 1 kg: 100~200 mL. The immersion time of the quaternary ammonium salt surfactant solution is 15-20 min.

[0010] Preferably, the method of injecting the embedding agent using the layered infusion method is as follows: Add the first portion of embedding agent to 1 / 3 to 1 / 2 of the core height, allow it to stand to remove bubbles, then add the remaining embedding agent and allow it to stand to solidify.

[0011] Preferably, the temperature for the static defoaming process is 15~30℃, and the time is 20~40min; The static curing temperature is 15~30℃, and the time is 24~48h.

[0012] Preferably, the sample box is rectangular in shape and made of wood or acrylic. The bottom of the sample box is sealed.

[0013] Preferably, the mass ratio of component A to component B in the epoxy resin AB adhesive mixture is 1:2.5~3; The mixing time of component A and component B in the epoxy resin AB adhesive mixture is 3-5 minutes.

[0014] This invention provides core specimens of vadose zone loose rock prepared by the above-described method.

[0015] This invention provides a method for preparing core specimens of vadose zone loose rocks. The method involves pretreating the vadose zone loose rock core with hydrogen peroxide solution and quaternary ammonium salt surfactant solution sequentially to obtain a pretreated core. The pretreated core is then placed in a sample box, and an embedding agent is injected using a layered injection method to cover the core. The embedding agent comprises a mixture of epoxy resin and AB adhesive. The core with the embedded agent is then allowed to solidify statically to obtain the vadose zone loose rock core specimen. This invention, through a process integrating surface treatment, chemical pretreatment, customized embedding, and solidification, maximizes the fixation and preservation of the original physical structure (such as bedding, fractures, and pores), water content, and material composition of water-bearing vadose zone loose rocks. It transforms these rocks into solid, transparent, long-term preservable, and easily observable and measurable solid specimens, providing high-quality basic materials for scientific research, teaching demonstrations, and engineering archiving in geology, environmental science, and other fields. Specifically, this invention uses hydrogen peroxide solution and quaternary ammonium salt surfactant solution for chemical pretreatment of the rock core, which serves a dual purpose: first, the mild oxidizing properties of hydrogen peroxide remove some organic matter interference and alter the surface hydrophilicity; second, the surfactant reduces the tension at the three-phase interface between the rock core particles, water, and subsequent embedding agent, enhancing the embedding agent's wetting and binding ability on the moist rock core surface and preventing large-area debonding or air bubbles caused by water repulsion. This invention employs a layered injection method, which avoids the large number of air bubbles generated by the release of pore gas from the rock core during a single injection, while also reducing air bubble formation caused by the interaction between the embedding agent and water.

[0016] Compared with the prior art, the method of the present invention has the following significant advantages: ① Excellent preservation of original state: Through pretreatment and layered embedding technology, the embedding agent can well wet and penetrate into the surface of the moist rock core, forming a solid support, and "freezing" the original structure such as loose particles, fine stratification, and biological pores completely in the transparent medium, effectively preventing structural damage during transportation and storage.

[0017] ② Effective preservation of in-situ information: The pretreatment steps reduce the physicochemical changes caused by rapid water evaporation. The dense sealing layer formed by the embedding agent isolates the air, allowing the water content and material composition inside the core to be preserved stably for a long time, which makes it possible to conduct subsequent micro-area chemical composition analysis (such as micro-area XRF after slicing).

[0018] ③ Easy to operate and highly adaptable: The required reagents and equipment are all commercially available, and the main steps can be completed in a field camp or simple laboratory without the need for complex instruments. The method and process are clear, the professional background requirements for operators are relatively lenient, and it is easy to promote.

[0019] ④ High-quality specimens with wide applications: The prepared specimens are sturdy and durable, with good transparency, facilitating 360-degree observation of the macroscopic and microscopic characteristics of the rock core. They can be used not only for scientific research and analysis and teaching demonstrations, but also for long-term preservation as important geological archives, with a value far exceeding that of ordinary disturbed samples or image data. Attached Figure Description

[0020] Figure 1 This is a photograph of the core specimen of the vadose zone loose rock obtained in Example 1; Figure 2 This is a photograph of the core specimen of the vadose zone loose rock obtained in Example 2; Figure 3 This is a photograph of the core specimen of the vadose zone loose rock obtained in Example 3; Figure 4 A photograph of the core specimen of the vadose zone loose rock obtained in Comparative Example 1; Figure 5 A photograph of the core specimen of the vadose zone loose rock obtained in Comparative Example 2; Figure 6 A photograph of the core specimen of the vadose zone loose rock obtained in Comparative Example 3; Figure 7 This is a photograph of the core specimen of the vadose zone loose rock obtained in Comparative Example 4. Detailed Implementation

[0021] This invention provides a method for preparing a core specimen of loose rock in the vadose zone, comprising the following steps: The loose rock cores in the vadose zone were pretreated sequentially with hydrogen peroxide solution and quaternary ammonium salt surfactant solution to obtain pretreated rock cores; The pretreated rock core was placed in a sample box, and an embedding agent was injected using a layered injection method to cover the rock core; the embedding agent included a mixture of epoxy resin and AB glue. The core samples were statically solidified after being injected with the embedding agent to obtain loose rock core specimens in the vadose zone.

[0022] In this invention, prior to the pretreatment, the surface of the collected vadose zone loose rock core is cleaned. This invention does not have specific requirements for the collection method of the vadose zone loose rock core; any collection method well-known to those skilled in the art can be used. After collection, this invention preferably performs preliminary observation and photography immediately upon extraction of the core, followed by temporary sealing to minimize moisture evaporation and structural disturbance. In this invention, the sealing material used for the temporary sealing is preferably one or more of plastic wrap, aluminum foil, and rubber sleeves.

[0023] In this invention, the surface cleaning is preferably performed to remove foreign impurities such as drilling mud and mud skin.

[0024] This invention pretreats vadose zone loose rock cores sequentially with hydrogen peroxide solution and quaternary ammonium salt surfactant solution to obtain pretreated cores. In this invention, the mass concentration of the hydrogen peroxide solution is preferably 3-10%, more preferably 5-8%; the pretreatment method of the hydrogen peroxide solution is preferably spraying or impregnation. In this invention, the mass ratio of the core to the volume of the hydrogen peroxide solution during spraying is preferably 1 kg: 50-100 mL, more preferably 1 kg: 60-80 mL; after spraying, it is preferably left to stand for 10-15 min, more preferably 12-13 min; the impregnation time with the hydrogen peroxide solution is 10-15 min, more preferably 12-13 min.

[0025] In this invention, the quaternary ammonium salt surfactant includes one or more of dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octadecyltrimethylammonium chloride, benzalkonium chloride, dodecyl dimethylbenzylammonium chloride, octadecyl dimethylbenzylammonium chloride, and polyquaternary ammonium salts. In this invention, the mass concentration of the quaternary ammonium salt surfactant solution is preferably 0.1-0.5%, more preferably 0.2-0.4%. In this invention, the pretreatment method of the quaternary ammonium salt surfactant solution is preferably spraying or wetting. During spraying, the mass ratio of the rock core to the volume of the quaternary ammonium salt surfactant solution is 1 kg: 100-200 mL, more preferably 1 kg: 150 mL. After spraying, it is preferably left to stand for 15-20 min, more preferably 16-18 min. The wetting time of the quaternary ammonium salt surfactant solution is preferably 15-20 min, more preferably 16-18 min.

[0026] In this invention, after pretreatment with the quaternary ammonium salt surfactant solution, excess liquid on the surface of the pretreated core is preferably absorbed, and the absorbent material is preferably dust-free absorbent paper. After absorbing the excess liquid, the pretreated core is preferably dried until the surface feels slightly damp but without any wet marks. In this invention, the drying method is preferably to place it in a ventilated place for air drying, the air drying temperature is preferably room temperature, and the time is preferably 30 minutes.

[0027] In this invention, the pretreated rock core is placed in a sample container, and an embedding agent is injected using a layered injection method to cover the rock core. In this invention, the embedding agent comprises a mixture of epoxy resin and AB adhesive.

[0028] In this invention, the epoxy resin AB adhesive is preferably commercially available, wherein component A is epoxy resin, preferably bisphenol A type epoxy resin, and component B is the corresponding curing agent, preferably an amine curing agent, and more preferably an aliphatic amine curing agent. In this invention, the mass ratio of component A to component B in the epoxy resin AB adhesive mixture is preferably 1:2.5~3, more preferably 1:2.6~2.8. Alternatively, the volume ratio of component A to component B is preferably 1:2~2.5, more preferably 1:2.2~2.4, and the total amount prepared at one time should not exceed 500 mL. In this invention, the epoxy resin AB adhesive has the advantages of high transparency, low shrinkage after curing, and stable chemical properties, making it suitable as an embedding agent for core specimens of loose rocks in the vadose zone.

[0029] This invention mixes components A and B of an epoxy resin AB adhesive mixture to obtain the epoxy resin AB adhesive mixture. In this invention, the mixing method is preferably to use a stirring rod to slowly and thoroughly stir in the same direction at a stirring speed of 60-90 rpm until the mixture is clear and transparent, without obvious filaments. It is then allowed to stand, allowing the air bubbles entrained during stirring to rise and escape naturally. This step is crucial to ensuring the final specimen is transparent and flawless. In this invention, the mixing time of components A and B in the epoxy resin AB adhesive mixture is preferably 3-5 minutes, more preferably 4 minutes. In this invention, after mixing, the resulting mixture is preferably allowed to stand and defoam for 10-20 minutes, more preferably 15 minutes.

[0030] In this invention, the sample box is rectangular in shape and made of wood or acrylic. The width of the sample box is preferably 5-10 mm larger than the core diameter, and the length is preferably 2-3 cm larger than the core diameter to allow space for the embedding agent. The wall thickness of the sample box is preferably 10-15 mm.

[0031] In this invention, the bottom of the sample box is preferably sealed, and the sealing material is preferably an embedding agent, which is more preferably the aforementioned embedding agent. In this invention, the thickness of the sealing material is preferably 8-15 mm, more preferably 10 mm. Screws are preferably used to assemble the sample box in this invention.

[0032] In this invention, the preferred method for injecting the embedding agent using the layered infusion method is: Add the first portion of embedding agent to 1 / 3 to 1 / 2 of the core height, allow it to stand to remove bubbles, then add the remaining embedding agent and allow it to stand to solidify.

[0033] In this invention, the temperature for static defoaming is preferably 15~30℃, more preferably 20~25℃, and the time is preferably 20~40min, more preferably 30min. Through static defoaming, this invention allows the embedding agent to initially penetrate into the pores of the rock core surface and allows air bubbles to escape.

[0034] In this invention, the static curing is preferably carried out in a stable and dust-free environment. The static curing temperature is 15-30°C, more preferably 20-25°C, and the curing time is preferably 24-48 hours, more preferably 36 hours. This invention effectively reduces air bubble defects inside the final specimen through static curing. After complete curing, this invention preferably checks whether the top liquid surface is sunken due to curing shrinkage; if so, it is filled with an embedding agent or sealed with a cap.

[0035] After the core specimen of the loose rock in the vadose zone is shaped, the present invention preferably disassembles the specimen box and performs carving, modification, and slicing on the obtained core specimen. As a specific embodiment of the present invention, the size of the sliced ​​specimen is 100cm in length. 6cm wide The core was 3cm high to preserve the stratigraphic structure, sedimentary sequence, water-bearing characteristics, and pollutant distribution of the original core profile to the greatest extent possible.

[0036] After obtaining the core specimen of the loose rock in the vadose zone, it is preferable to identify and record it. In this invention, the identification and recording method is preferably as follows: A waterproof label containing specimen information is made and affixed to the outer wall of the sample box; a corresponding electronic file is established to save data such as photos of the sampling site and bar chart descriptions. In this invention, the specimen information preferably includes one or more of the following: specimen number, geographical location, borehole number, sampling depth range, original moisture content description, sampler, and sampling date.

[0037] This invention provides core specimens of vadose zone loose rock prepared by the above-described method.

[0038] The following detailed description of the method for preparing core specimens of vadose zone loose rock provided by the present invention, with reference to the embodiments, should not be construed as limiting the scope of protection of the present invention.

[0039] Example 1 Taking a core sample containing water-rich, silty clay collected near the groundwater level (depth 4.0-8.0 meters) from a groundwater environmental quality survey project as an example, the method of this invention is used to prepare an undisturbed specimen. The specific method is as follows: ① Temporary Protection and Cleaning: Immediately after the core is removed, take photos from multiple angles using a high-definition camera, and tightly wrap it with pre-moistened plastic wrap before placing it in a core box lined with sponge. Upon returning to the temporary laboratory, carefully remove the plastic wrap. Gently remove any visible mud rings on the surface using a soft brush and scraper to reveal the clear natural structure and color of the soil.

[0040] ② Chemical Pretreatment: Prepare a 5wt% hydrogen peroxide solution and a 0.2wt% dodecyl dimethyl benzyl ammonium chloride solution. First, use a spray bottle to evenly spray the hydrogen peroxide solution onto the core surface until it is slightly moistened. The ratio of core to hydrogen peroxide solution is 1kg:100mL. Let it stand for 10 minutes. Then, use a spray bottle to spray a surfactant solution. The ratio of core to quaternary ammonium salt surfactant solution is 1kg:150mL. Let it stand for 15 minutes after spraying. Finally, gently attach clean, lint-free absorbent paper to the core surface to absorb excess liquid. Place the core in a ventilated area to air dry for 30 minutes, until the surface feels slightly damp but without wet marks. Measure the diameter of the pretreated core to be 8cm.

[0041] ③ Preparation of embedding agent: To avoid excessive heating and air bubbles caused by preparing too much at once, it was decided to prepare it in two batches. For the first batch, weigh 100g of epoxy resin A and 300g of epoxy resin B (A to B mass ratio 1:3), pour them into a disposable plastic cup, and stir with a glass rod in a clockwise direction at 80 rpm for 4 minutes until completely transparent. Let it stand for 15 minutes to defoam and set aside. For the second batch, prepare 500mL of embedding agent using the same method.

[0042] ④ Sample Box Preparation: A wooden box with an inner diameter of 9cm was selected as the sample box. The portion of the first batch of prepared embedding medium, after being allowed to stand and defoam, was slowly poured into the tube until the liquid level reached 1cm. After standing for 6 hours, the embedding medium solidified at the bottom of the sample box, forming a bottom plug.

[0043] ⑤ Core embedding: Carefully place the air-dried core vertically into the sample box, ensuring it sits stably on the bottom seal. Slowly pour the remaining embedding agent along the inner wall of the sample box until the liquid level reaches half the height of the core. Let it stand at room temperature (25℃) for 30 minutes; a small number of tiny bubbles will be visible escaping from the core surface to the liquid surface.

[0044] ⑥ Secondary infusion and final curing: After stirring and defoaming the second-prepared embedding agent, slowly inject it into the sample box until the liquid level is completely filled to 0.5 cm from the top of the sample box. Gently pop any large air bubbles remaining on the liquid surface with a fine needle. Place the entire sample box horizontally on a vibration-free rack and allow it to cure at room temperature for 36 hours.

[0045] ⑦ Sealing and Labeling: After curing, a shrinkage concave surface of about 1mm was found at the top. Fill it with a small amount of freshly prepared embedding agent. After curing, a waterproof label containing the sample information was pasted on.

[0046] The actual image of the obtained vadose zone loose rock core specimen is shown below. Figure 1 As shown, the specimens prepared by this invention can maintain the stratigraphic structure and sedimentary sequence of the original core profile.

[0047] Example 2 Taking a water-rich rock core sample (0-4.0 meters deep) collected from near the groundwater level in a groundwater environmental quality survey project as an example, the sample was prepared using the method in Example 1. The resulting vadose zone loose rock core sample is shown in the image below. Figure 2 As shown.

[0048] Example 3 Taking a water-rich rock core sample (0-10.0 meters deep) collected from near the groundwater level in a groundwater environmental quality survey project as an example, the sample was prepared using the method in Example 1. The resulting vadose zone loose rock core sample is shown in the image below. Figure 3 As shown.

[0049] Comparative Example 1 Based on Example 1, the hydrogen peroxide solution pretreatment step was omitted, and the resulting core specimen of the loose rock in the vadose zone is shown in the image below. Figure 4 As shown. By Figure 4 It can be seen that the organic matter and impurities on the surface of the core were not effectively decomposed and removed. The surface of the specimen was dark in color and the structure was blurred. There were stains and mottled traces in some areas. The original stratigraphic texture and sedimentary sequence were significantly reduced in recognition. The overall appearance was not clean and the profile was not clear.

[0050] Comparative Example 2 Based on Example 1, the pretreatment step with dodecyl dimethyl benzyl ammonium chloride solution was omitted. The resulting core sample of the loose rock in the vadose zone is shown in the image below. Figure 5 As shown. By Figure 5 It can be seen that the core surface has poor wettability, the embedding agent is not tightly bonded to the core interface, there are obvious gaps, microbubble aggregation and local debonding phenomena, the integrity and stability of the specimen are insufficient, and the original structure is easily disturbed.

[0051] Comparative Example 3 Based on Example 1, the dodecyl dimethyl benzyl ammonium chloride solution was replaced with a fatty alcohol polyoxyethylene ether solution with a concentration of 0.3 wt%. The resulting core sample of the loose rock in the vadose zone is shown in the image below. Figure 6 As shown. By Figure 6 It can be seen that the surface wetting and penetration effects are not good, the core is unevenly wetted in some areas, there are still air bubbles after embedding, the interfacial bonding strength is weak, and the integrity of the profile and the uniformity of light transmission are not as good as the specimens using quaternary ammonium salt surfactants.

[0052] Comparative Example 4 Based on Example 1, the secondary perfusion was replaced with a single perfusion of the embedding agent until the liquid level completely filled the sample box to a height of 0.5 cm from the top. The sample was then allowed to solidify at room temperature for 36 hours. The resulting core sample of the loose rock in the vadose zone is shown in the image below. Figure 7 As shown. By Figure 7 It can be seen that the single injection resulted in a large amount of heat generated during the solidification of the embedding agent, and the internal air bubbles could not be fully expelled. A large number of air bubbles and cavities appeared inside the specimen. Uneven solidification shrinkage caused obvious deformation and cracks, the original structure of the rock core was destroyed, and the integrity of the profile was seriously damaged.

[0053] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a core specimen of loose rock in the vadose zone, characterized in that, Includes the following steps: The loose rock cores in the vadose zone were pretreated sequentially with hydrogen peroxide solution and quaternary ammonium salt surfactant solution to obtain pretreated rock cores; The pretreated rock core was placed in a sample box, and an embedding agent was injected using a layered injection method to cover the rock core; the embedding agent included a mixture of epoxy resin and AB glue. The core samples were statically solidified after being injected with the embedding agent to obtain loose rock core specimens in the vadose zone.

2. The manufacturing method according to claim 1, characterized in that, Before the pretreatment, the surface of the collected vadose zone loose rock core is also cleaned.

3. The manufacturing method according to claim 1, characterized in that, The mass concentration of the hydrogen peroxide solution is 3-10%; The pretreatment method of the hydrogen peroxide solution is spraying or impregnation; when spraying, the mass ratio of the rock core to the volume of the hydrogen peroxide solution is 1 kg: 50~100 mL; The hydrogen peroxide solution soaking time is 10-15 minutes.

4. The manufacturing method according to claim 1, characterized in that, The quaternary ammonium salt surfactants include one or more of dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octadecyltrimethylammonium chloride, benzalkonium chloride, dodecyl dimethylbenzylammonium chloride, octadecyl dimethylbenzylammonium chloride, and polyquaternary ammonium salts.

5. The manufacturing method according to claim 1 or 4, characterized in that, The mass concentration of the quaternary ammonium salt surfactant solution is 0.1~0.5%; The pretreatment method of the quaternary ammonium salt surfactant solution is spraying or wetting; when spraying, the mass ratio of the rock core to the volume ratio of the quaternary ammonium salt surfactant solution is 1 kg: 100~200 mL. The immersion time of the quaternary ammonium salt surfactant solution is 15-20 min.

6. The manufacturing method according to claim 1, characterized in that, The method of injecting the embedding agent using the layered infusion method is as follows: Add the first portion of embedding agent to 1 / 3 to 1 / 2 of the core height, allow it to stand to remove bubbles, then add the remaining embedding agent and allow it to stand to solidify.

7. The manufacturing method according to claim 6, characterized in that, The temperature for the static defoaming process is 15~30℃, and the time is 20~40min; The static curing temperature is 15~30℃, and the time is 24~48h.

8. The manufacturing method according to claim 1, characterized in that, The sample box is rectangular in shape and made of wood or acrylic. The bottom of the sample box is sealed.

9. The manufacturing method according to claim 1, characterized in that, The mass ratio of component A to component B in the epoxy resin AB adhesive mixture is 1:2.5~3; The mixing time of component A and component B in the epoxy resin AB adhesive mixture is 3-5 minutes.

10. A core specimen of loose rock in the vadose zone prepared by the method described in any one of claims 1 to 9.

Images