A method for non-destructively producing a multi-angle multi-layered layered cylindrical sample

Abstract

The present application belongs to the field of rock mechanics test, and proposes a kind of multi-angle multi-layering layered compaction layered cylindrical sample nondestructive production method: first, the quantitative mixture of first layering is poured into the sample mold, the end of the inclined block is contacted with the quantitative mixture, the other horizontal end is compacted using compactor, and the position of the longest generatrix is recorded on the horizontal end surface of the inclined block;Then the inclined block is taken out, the quantitative mixture of second layering is poured into the mold, the inclined block is rotated to the recording position of the first step generatrix, and then the inclined block and the compactor are used again to compact it;Finally, the inclined block is taken out, the quantitative mixture of third layering is poured above the second layering, the two-end horizontal block and the compactor are used to compact it, and it is left for 20 min, and then demolding is carried out after stabilization.The present application restores the rock-forming process of layered stratum, realizes layered nondestructive production of laboratory sample, and solves the problem of layered sample production difficulty.

Description

Technical Field

[0001] This invention belongs to the field of rock mechanics testing and relates to a method for preparing layered cylindrical specimens. Background Technology

[0002] Layered rocks are extremely common in rock mechanics engineering. However, due to their well-developed bedding and low interlayer strength, they are highly susceptible to splitting failure under external forces. Sampling in the field is difficult, as is processing large rock blocks into test specimens that meet testing standards. This makes obtaining the physical and mechanical parameters of layered rocks challenging. Therefore, there is an urgent need for a method to prepare layered rocks that can highly reproduce the rock compaction process, solving the problem of preparing layered rock specimens, providing a foundation for accurately measuring their relevant mechanical parameters, and guiding safe construction in related rock mechanics engineering projects. Summary of the Invention

[0003] To address the aforementioned challenges, the present invention aims to propose a non-destructive method for fabricating multi-angle, multi-layered, and compacted layered cylindrical specimens. This invention is achieved through the following technical solution:

[0004] First, pour the first layer of quantitative mixture into the mold. Use a pressure block with one end tilted and the other end horizontal to contact the mixture. After compaction with a compactor, record the position with the longest generatrix of the pressure block. Then, remove the tilted pressure block and pour the second layer of quantitative mixture onto the top of the second layer, with the tilted end of the pressure block facing down. Rotate the pressure block to the position of the generatrix of the pressure block recorded in the first step and compact it with a compactor. Finally, remove the tilted pressure block and pour the third layer of quantitative mixture onto the top of the second layer. Compact it with a pressure block with both ends horizontal and a compactor. Maintain the pressure and let it stand for 20 minutes to stabilize before demolding.

[0005] The sample mold consists of two semi-cylinders with arc-shaped flanges that are vertically joined together. After the flanges pass through the bolts on the base, nuts are used to connect the two semi-cylinders and the base. The mold height is 130 mm.

[0006] The angle of the inclined surface of the pressure block, which is inclined at one end and horizontal at the other end, is consistent with the layering angle of the target layered sample, and its range is 0°~90°.

[0007] The length of the longest generatrix of the pressure block, which is inclined at one end and horizontal at the other, is greater than or equal to the height of the mold by 130 mm, which allows the pressure block to be higher than the mold, leaving space for the compactor.

[0008] The inclined end face of the inclined block is facing down, and after being rotated to the position of the block generatrix recorded in the first step, it is compacted using a compactor. This is so that when compacting the second layer, the longest position of the block generatrix is ​​consistent with the position of the first layer, resulting in two parallel layers.

[0009] The phrase "maintain pressure and allow it to stabilize for 20 minutes before demolding" means that after compaction by the compactor, the pressure is maintained for 20 minutes until the layered samples are bonded together before demolding.

[0010] The first layer is horizontal at the bottom and sloping at the top; the second layer is sloping at the bottom and sloping at the top; and the third layer is sloping at the bottom and horizontal at the top. After being compacted by a compactor, the three layers form a complete layered sample.

[0011] The number of the first, second, and third layers is related to the number of strata, and is one layer more than the number of strata.

[0012] The volume of the layered mixture can be quantitatively calculated based on the density of the mixture. The mixture can be a combination of cement, river sand, coal powder, or similar materials with pure water.

[0013] As can be seen from the technical solution of this invention, a non-destructive method for preparing multi-angle, multi-layered, layered, compacted cylindrical specimens involves pouring a quantitative mixture of the first layer into a mold, compacting it with a block that is horizontal at one end and inclined at the other, recording the position of the longest generatrix of the block, and then removing the block. Next, a quantitative mixture of the second layer is poured onto the first layer, and the longest generatrix of the block, which is horizontal at one end and inclined at the other, is aligned with the initially recorded position, continuing to compact the second layer. Finally, the inclined block is removed, and a quantitative mixture of the third layer is poured onto the second layer, compacted with a block that is horizontal at both ends, and held under pressure for 20 minutes before demolding. This method of preparing layered rock specimens can produce multi-angle, multi-layered rock specimens by changing the angle of the inclined surface of the block and the number of layers. Furthermore, the different layers are naturally bonded through compaction using a compactor, without the use of additional external adhesives, highly replicating the diagenetic process of layered rocks and minimizing the influence of interface effects on the mechanical parameters of layered rocks. In summary, this invention has the advantages of convenient operation and high fidelity, solving the problem of preparing layered rock specimens. Attached Figure Description

[0014] Figure 1 A schematic diagram of a non-destructive fabrication method for multi-angle, multi-layer, layered compaction of layered cylindrical specimens;

[0015] Figure 2 This is a schematic diagram of the compaction of a layered sample;

[0016] Figure 3 This is a schematic diagram of a compactor;

[0017] Figure 4 This is a schematic diagram of the sample mold.

[0018] Among them, 1-sample mold; 2-compactor lower head; 3-inclined compactor block; 4-horizontal compactor block; 5-layered rock sample; 6-reverse jack; 7-handle; 8-compactor; 9-hydraulic valve; 10-compactor upper support plate; 11-compactor threaded support; 12-compactor base; 13-bolt; 14-washer; 15-mold flange; 16-mold base Detailed Implementation

[0019] This invention provides a non-destructive method for fabricating layered cylindrical specimens using multi-angle, multi-layered, and layered compaction. To make the invention's objectives, technical solutions, and effects clearer and more explicit, the following schematic diagrams are used to further illustrate its implementation. It should be understood that the schematic diagrams described herein are merely illustrative and not intended to limit the invention. Specific implementation methods are as follows:

[0020] A non-destructive method for fabricating a multi-angle, multi-layer, layered, compacted, layered cylindrical specimen consists of the following steps: First, the quantitative mixture of the first layer is poured into a mold (1). The inclined surface of a pressure block (3) with one end tilted and the other end horizontal is brought into contact with the mixture. After compaction with a compactor (8), the position of the longest generatrix of the pressure block (3) is recorded. Then, the inclined pressure block (3) is removed, and the quantitative mixture of the second layer is poured onto the top of the second layer. The inclined end face of the inclined pressure block (3) is facing down, and it is rotated to the position of the generatrix of the pressure block (3) recorded in the first step. Then, the compactor (8) is used for compaction. Finally, the inclined pressure block (3) is removed, and the quantitative mixture of the third layer is poured onto the top of the second layer. The pressure is compacted using a pressure block (4) with both ends horizontal and a compactor (8). After the pressure is stabilized for 20 minutes, the specimen is demolded. A schematic diagram of the overall fabrication method of this invention is shown below. Figure 1 .

[0021] The first layer of quantitative mixture is poured into mold (1). The inclined surface of the pressure block (3) with one end inclined and the other end horizontal is in contact with the mixture. After compaction with compactor (8), the position of the longest generatrix of the pressure block (3) is recorded. The height of mold (1) is 130 mm and the diameter is 51 mm. The diameter of the pressure block (3) with one end inclined and the other end horizontal is 50 mm. The length of the longest generatrix is ​​greater than or equal to the height of mold (1) 130 mm. The angle of the inclined surface of the pressure block (3) is consistent with the stratification angle in the sample (5) and the range is 0°~90°.

[0022] After compaction by the compactor (8), record the position of the longest line of the compaction block (3). For easy recording, this position is best located at the connection point of the two semi-cylinders of the mold (1).

[0023] When the compactor (8) is compacting, moving the handle (7) of the compactor (8) up and down can move the lower pressure head (2) of the reverse jack (6) downward until it contacts the horizontal pressure block (4), and then continue to apply pressure to the specified pressure.

[0024] The compactor (8) consists of a handle (7), a reverse jack (6), an upper support plate (10), a threaded support column (11), a base (12), and bolts (13). The upper support plate (10) and the base (12) are connected using the threaded support column (11) and fixed using the bolts (13). Then, the reverse jack (6) is passed through the threaded wedge-shaped hole reserved in the upper support plate (10) of the compactor.

[0025] The inclined end face of the inclined pressure block (3) is facing down and rotated to the position of the generatrix of the pressure block (3) recorded in the first step. At this time, the position of the longest generatrix of the inclined pressure block (3) should also be rotated to the connection point of the two semi-cylinders of the mold (1) when the first layer is compacted. This ensures that the two layered surfaces formed are parallel to each other.

[0026] The mold (1) is composed of two semi-cylinders with flanges (15) and a base (16) connected together, and then connected with gaskets (14), bolts and nuts. The material is stainless steel.

[0027] After maintaining pressure and allowing it to stabilize for 20 minutes, demold. The entire process (see...) Figure 2 The compactor handle (7) needs to be kept still. After the layered rock sample (5) containing stratification stabilizes for 20 minutes, the hydraulic valve (9) of the compactor is opened. After the lower pressure head (2) of the compactor rises and the pressure is released, the pressure block (4) and the mold (1) are taken out together. First, remove the pressure block (4), and then use a wrench to disassemble the two semi-cylinders of the mold (1) to obtain the complete layered rock sample (5).

[0028] The number of layers, bedding angle, and bedding spacing of the layered rock sample (5) can be set according to the test requirements. However, the number of layers should be one more than the number of bedding layers. Under the premise that the final height of the complete sample (5) is 100 mm in line with the test standard, the volume of each layer is calculated based on the density of the mixture.

[0029] The mixture that forms the layered rock sample (5) can be a combination of similar materials such as river sand, cement, coal powder and pure water in a certain proportion.

[0030] The above description is merely a preferred embodiment. The scope of protection of this invention is not limited thereto; any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this invention should be included within the scope of protection of this invention.

Claims

1. A non-destructive method for fabricating multi-angle, multi-layered, layered, compacted, layered cylindrical specimens, characterized in that: First, pour the first layer of quantitative mixture into the mold. Use a pressure block with one end tilted and the other end horizontal to contact the mixture. After compaction with a compactor, record the position with the longest generatrix of the pressure block. Then, remove the tilted pressure block and pour the second layer of quantitative mixture onto the top of the second layer, with the tilted end of the pressure block facing down. Rotate the pressure block to the position of the generatrix of the pressure block recorded in the first step and compact it with a compactor. Finally, remove the tilted pressure block and pour the third layer of quantitative mixture onto the top of the second layer. Compact it with a pressure block with both ends horizontal and a compactor. Maintain the pressure and let it stand for 20 minutes to stabilize before demolding.

2. The method for non-destructive fabrication of a multi-angle, multi-layered, layered, compacted, layered cylindrical specimen according to claim 1, characterized in that: The mold containing the mixture is 130mm high and 51mm in diameter. It consists of two semi-cylinders and a base, and the semi-cylinders and the base are connected by bolts and nuts.

3. The method for non-destructive fabrication of a multi-angle, multi-layered, layered, compacted, layered cylindrical specimen according to claim 1, characterized in that: The angle of the inclined surface of the pressure block, which is inclined at one end and horizontal at the other end, is the same as the angle of the stratification surface. It can be designed according to the desired stratification angle, ranging from 0° to 90°. The longest generatrix length of the pressure block is greater than or equal to the height of the mold by 130mm.

4. The method for non-destructive fabrication of a multi-angle, multi-layered, layered, compacted, layered cylindrical specimen according to claim 1, characterized in that: The number of layers can be adjusted according to the number of strata, but the number of layers should be one more than the number of strata. The volume of each layer mixture should be quantitatively calculated based on its density.

5. The method for non-destructive fabrication of a multi-angle, multi-layered, layered, compacted, layered cylindrical specimen according to claim 1, characterized in that: The mixture can be a combination of cement, river sand, coal powder or other similar materials and pure water, and can be mixed in a certain proportion according to the lithology of the target rock sample.

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