Liquid-plastic limit testing device for fine-grained soil

Abstract

The utility model discloses a fine-grained soil liquid-plastic limit test device, which belongs to the technical field of fine-grained soil liquid-plastic limit, and comprises a bottom plate, the bottom plate is fixedly connected with a mixing cylinder through a support column, a rotating shaft is rotatably arranged in the mixing cylinder, the lower end of the mixing cylinder is funnel-shaped, a spiral auger matched with the mixing cylinder is fixedly arranged at the lower end of the rotating shaft, and the lower end of the spiral auger is fixedly connected with the bottom plate. And the two sides of the rotating shaft above the spiral auger are fixedly connected with scraping plates attached to the inclined side wall of the mixing cylinder. According to the fine-grained soil liquid plastic limit testing device, during preparation, soil below is turned over to the upper portion through the spiral auger, stirring of a soil sample is achieved through cooperation of the spiral auger and the rotating scraper blade, and during filling, the spiral auger rotates reversely, and the soil in the mixing cylinder is evenly filled to the communicating pipe and the measuring tank downwards. And compared with the existing device, the problem that the pasty soil sample possibly stays at the discharge port and is difficult to discharge by virtue of self gravity is avoided. The working efficiency is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of liquid and plastic limits of fine-grained soil, in particular to a testing device for the liquid and plastic limits of fine-grained soil. Background Art

[0002] Engineering construction in my country has long been managed under administrative fragmentation, and there are some differences in the geotechnical testing regulations of the relevant specifications, procedures, and standards of each industry. In recent years, with the increase in construction projects and the regulation of national management mechanisms, cross-industry project undertakings have become commonplace. The China Democratic National Construction Association's survey units undertake survey projects in the municipal and highway industries. If the quantitative evaluation of the roadbed wet and dry types according to the China Democratic National Construction Association standards is significantly different from the actual situation, often with a difference of 1-2 levels, the roadbed that does not require treatment will need to be treated according to the quantitative evaluation conclusions, which indirectly increases the roadbed treatment fee. Fine-grained soil from different sites and locations is tested according to different standards. Through statistical analysis, a conversion formula between indicators is established to solve work problems in production, reduce unnecessary repetitive testing work, and make up for the lack of research work in this area. At the same time, it can also indirectly reduce the cost of survey projects and the test cycle.

[0003] Existing fine-grained soil liquid and plastic limit test devices mostly rely on manual filling when placing the prepared soil into the measuring tank, and the steps are relatively cumbersome. A few solutions rely on mechanical filling, such as a fine-grained soil liquid and plastic limit test device shown in the authorization publication number CN218470714U, which includes a base plate, a support rod, a mixing mechanism, a measuring cup, and a calibration mechanism. When the above patent is in use, the mixing rod is moved upward to drive the mixing plug to move upward so that the discharge port is opened, thereby realizing the discharge of the soil sample. However, during the liquid and plastic limit test, the water content of the soil needs to be repeatedly adjusted to reach the water content close to the liquid limit, the intermediate state and the plastic limit in turn, and adjusted into a uniform paste. The paste-like soil sample may stay at the discharge port, and it is difficult to discharge it by its own gravity. This affects the efficiency of the experiment.

[0004] To this end, we proposed a fine-grained soil liquid-plastic limit test device to solve the above problems. Utility Model Content

[0005] The utility model aims to solve the problems of troublesome material loading and unsatisfactory effect in the prior art, and proposes a liquid-plastic limit test device for fine-grained soil.

[0006] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0007] A fine-grained soil liquid-plastic limit test device comprises a base plate, the base plate being fixedly connected to a mixing drum via a support column, a rotating shaft being provided inside the mixing drum for rotation, the lower end of the mixing drum being funnel-shaped, a spiral auger being fixedly provided at the lower end of the rotating shaft for cooperating with the mixing drum, and scrapers being fixedly connected to both sides of the rotating shaft above the spiral auger for contacting the inclined side walls of the mixing drum;

[0008] It also includes a measuring tank placed on the bottom plate, and the measuring tank is located directly below the mixing drum;

[0009] A mounting frame is provided between the mixing cylinder and the measuring tank for horizontal sliding, and a connecting pipe and a measuring assembly are provided on both sides of the mounting frame.

[0010] Preferably, the upper end of the spiral auger is higher than the lower end of the scraper, and the lower end of the spiral auger is not lower than the bottom end of the mixing drum.

[0011] Preferably, the outer side of the spiral auger is in contact with the side wall of the mixing cylinder.

[0012] Preferably, the upper end of the connecting pipe cooperates with the lower end of the mixing cylinder, and the lower end cooperates with the upper end of the measuring tank.

[0013] Preferably, a baffle is provided on the side of the connecting pipe facing away from the measuring assembly, and the top surface of the baffle is flush with the top surface of the measuring tank.

[0014] Preferably, a side of the baffle away from the measuring component is fixedly connected to a limit plate.

[0015] Preferably, a protrusion is fixedly connected to the upper end of the communicating tube on the side facing the limiting plate, and a limiting groove cooperating with the protrusion is formed on the outer side wall of the mixing cylinder facing the limiting plate.

[0016] In summary, the technical effects and advantages of this utility model are as follows: During preparation, the spiral auger flips the soil from the bottom to the top, and the rotating scraper stirs the soil sample. During filling, the spiral auger reverses and evenly loads the soil in the mixing drum downward to the connecting pipe and measuring tank. Compared with existing devices, this avoids the problem of paste-like soil samples being retained at the discharge port, making it difficult to discharge by gravity, thereby improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of the utility model;

[0018] Figure 2 This is a schematic diagram of the structure of the protrusion of the utility model;

[0019] Figure 3 This is a front cross-sectional view of the measuring assembly of the present invention when in use.

[0020] In the figure: 1. Base plate; 2. Support column; 3. Mixing drum; 4. Rotating shaft; 5. Auger; 6. Scraper; 7. Measuring tank; 8. Mounting frame; 9. Connecting pipe; 10. Measuring assembly; 11. Baffle; 12. Limit plate; 13. Bump; 14. Limit groove. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0022] Reference Figure 1-3 , a fine-grained soil liquid plastic limit test device, including a base plate 1, the base plate 1 is fixedly connected to a mixing drum 3 through a support column 2. A feeding port for soil samples and water to enter is provided on the top surface of the mixing drum 3. A rotating shaft 4 is provided inside the mixing drum 3, and the lower end of the mixing drum 3 is funnel-shaped. A spiral auger 5 that cooperates with the mixing drum 3 is fixedly provided at the lower end of the rotating shaft 4, and scrapers 6 that fit the inclined side walls of the mixing drum 3 are fixedly connected on both sides of the rotating shaft 4 above the spiral auger 5. The power source of the rotating shaft 4 can be manpower or electricity, and both are existing technical solutions. The solution of using a motor to drive the rotating shaft 4 to rotate will be explained later.

[0023] The mixing drum 3 further comprises a measuring tank 7 placed on the bottom plate 1 , and the measuring tank 7 is located directly below the mixing drum 3 .

[0024] A mounting bracket 8 is provided between the mixing drum 3 and the measuring tank 7 for horizontal sliding. Figure 1-3 A slide rail is fixedly connected between the two support columns 2 shown, and the mounting frame 8 should be slidably connected to the slide rail, thereby sliding horizontally relative to the mixing drum 3. A connecting pipe 9 and a measuring assembly 10 are respectively provided on both sides of the mounting frame 8. The measuring assembly 10 is a prior art and includes a cone and a distance measuring assembly for measuring the distance the cone moves. An adjustment platform can also be provided on the base plate 1 to drive the measuring tank 7 up and down to ensure that the top of the measuring tank 7 is flush with the bottom of the connecting pipe 9. Since the measuring assembly 10 and the adjustment platform are relatively common in the field of liquid limit and plastic limit determination, they will not be described in detail.

[0025] During use, this fine-grained soil liquid plastic limit test device rotates forward as the shaft 4 rotates, causing the auger 5 and scraper 6 to stir and condition the soil sample. Once completed, the shaft 4 rotates in the reverse direction, causing the auger 5 to rotate and transfer the soil sample from the mixing drum 3 through the connecting pipe 9 and into the measuring tank 7. Once both the connecting pipe 9 and the measuring tank 7 are filled, the auger 5 continues to rotate, compacting the soil sample in the measuring tank 7. This results in more accurate measurements.

[0026] After filling is complete, the rotating shaft 4 rotates forward, and the auger 5 flips the soil sample at the bottom of the mixing drum 3 upward to avoid affecting subsequent measurements. The mounting bracket 8 is then moved leftward, and the connecting pipe 9 moves and scrapes the soil sample in the measuring tank 7. Once the measuring assembly 10 is above the measuring tank 7, the liquid and plastic limit test of the soil sample in the measuring tank 7 can begin.

[0027] The upper end of the auger 5 is higher than the lower end of the scraper 6. This allows the auger 5 to turn over as much soil as possible, increasing the mixing speed. The lower end of the auger 5 is not lower than the bottom end of the mixing drum 3. This prevents the connecting tube 9 from colliding with the auger 5 during movement. At the same time, the lower end of the auger 5 is kept as close to the lower end of the mixing drum 3 as possible. This ensures that when the auger 5 rotates, the soil sample at the bottom of the mixing drum 3 is turned upward as much as possible, preventing the soil sample from falling out when the connecting tube 9 moves.

[0028] To prevent the soil sample from falling directly from the gap between the auger 5 and the mixing drum 3, the outer side of the auger 5 is in contact with the side wall of the mixing drum 3. Since most soil samples are in a paste-like state and have strong adhesion, it is difficult for the soil sample to fall directly from the auger 5 blades when the auger 5 stops.

[0029] The upper end of the connecting pipe 9 cooperates with the lower end of the mixing cylinder 3, and the lower end cooperates with the upper end of the measuring tank 7. The connecting pipe 9 realizes the communication between the mixing cylinder 3 and the measuring tank 7, and avoids the soil sample from escaping as much as possible.

[0030] As connecting tube 9 moves and scrapes the soil sample inside measuring tank 7, it can fall onto base plate 1, making it difficult to clean. To prevent this, a baffle 11 is installed on the side of connecting tube 9 facing away from measuring assembly 10. The top surface of baffle 11 is flush with the top surface of measuring tank 7. This baffle 11 improves the practicality of the device by ensuring that the soil sample inside connecting tube 9 is level.

[0031] To limit the movement of mounting bracket 8, a limit plate 12 is fixedly connected to the side of baffle 11 away from measuring assembly 10. When limit plate 12 is in contact with connecting pipe 9, measuring assembly 10 is directly above measuring tank 7, facilitating testing.

[0032] like Figure 1 As shown, the baffle 11 and the limiting plate 12 can directly use L-shaped plates and be fixed on the support rod.

[0033] A protrusion 13 is fixedly attached to the upper end of the connecting pipe 9, facing the stop plate 12. A retaining groove 14 is formed on the outer wall of the mixing drum 3, facing the stop plate 12, which mates with the protrusion 13. When the retaining groove 14 engages with the protrusion 13, the connecting pipe 9 connects the mixing drum 3 and the measuring tank 7. This prevents excessive movement of the mounting bracket 8, which could cause the connecting pipe 9 to become misaligned with the mixing drum 3.

[0034] The above is only a preferred specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with the technical field within the technical scope disclosed by the present invention can make equivalent replacements or changes based on the technical solution and utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A fine-grained soil liquid-plastic limit test device, comprising a base plate (1), characterized in that: The bottom plate (1) is fixedly connected to a mixing drum (3) via a support column (2); a rotating shaft (4) is provided inside the mixing drum (3) for rotation; the lower end of the mixing drum (3) is funnel-shaped; a spiral auger (5) cooperating with the mixing drum (3) is fixedly provided at the lower end of the rotating shaft (4); scrapers (6) that fit the inclined side walls of the mixing drum (3) are fixedly connected to both sides of the rotating shaft (4) above the spiral auger (5); It also includes a measuring tank (7) placed on the bottom plate (1), and the measuring tank (7) is located directly below the mixing drum (3); A mounting frame (8) is horizontally slidably provided between the mixing cylinder (3) and the measuring tank (7), and a connecting pipe (9) and a measuring assembly (10) are respectively provided on both sides of the mounting frame (8).

2. A fine-grained soil liquid-plastic limit test device according to claim 1, characterized in that: The upper end of the spiral auger (5) is higher than the lower end of the scraper (6), and the lower end of the spiral auger (5) is not lower than the bottom end of the mixing cylinder (3).

3. A fine-grained soil liquid-plastic limit test device according to claim 2, characterized in that: The outer side of the spiral auger (5) is in contact with the side wall of the mixing cylinder (3).

4. The fine-grained soil liquid-plastic limit test device according to claim 1, characterized in that: The upper end of the communicating pipe (9) is matched with the lower end of the mixing cylinder (3), and the lower end is matched with the upper end of the measuring tank (7).

5. The fine-grained soil liquid-plastic limit test device according to claim 1, characterized in that: A baffle (11) is provided on the side of the connecting pipe (9) facing away from the measuring assembly (10), and the top surface of the baffle (11) is flush with the top surface of the measuring tank (7).

6. The fine-grained soil liquid-plastic limit test device according to claim 5, characterized in that: The side of the baffle (11) away from the measuring component (10) is fixedly connected to a limit plate (12).

7. The fine-grained soil liquid-plastic limit test device according to claim 6, characterized in that: The upper end of the connecting pipe (9) on one side facing the limiting plate (12) is fixedly connected with a protrusion (13), and the outer side wall of the mixing cylinder (3) facing the limiting plate (12) is provided with a limiting groove (14) that matches the protrusion (13).

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