Reducing sample cutting instrument for preparing soil body sample for geotechnical tensile test

Abstract

The utility model discloses a variable diameter sample cutting instrument for preparing a soil body sample for geotechnical tensile test, which comprises a bottom plate, the top surface of the bottom plate is respectively provided with a clamp guide rail and a cutting guide rail, the clamp guide rail is provided with a first moving seat matched with the clamp guide rail, the first moving seat is rotatably connected with a moving clamp, and the moving clamp is rotatably connected with the cutting guide rail. A fixing base is welded to the right side of the top surface of the bottom plate, a fixing clamp is rotationally connected to the fixing base, and a first belt wheel is installed on a rotating shaft of the fixing clamp. According to the variable-diameter sample cutting instrument for preparing the soil body sample for the geotechnical tensile test, an electric mode and a manual mode can be freely switched, the size control precision is high, the instrument can be controlled by adopting a sample preparation program, different cutting tools can be adopted to be matched with different cutting modes, soil bodies of different structures can be cut, and the working efficiency is improved. The device is suitable for different types of tensile tests, is convenient to operate, can adopt different cutting rates, and can cut soil bodies with different structures.

Description

Technical Field

[0001] The utility model relates to the technical field of soil sample diameter-changing cutting, in particular to a soil sample diameter-changing cutting instrument used for preparing soil samples for geotechnical tensile tests. Background Art

[0002] The conventional method of making soil samples in tensile tests is to fill the layers in parallel, which has three shortcomings. First, the bonding force between the contact surfaces of each layer is weak and easy to pull apart. Second, the lower layer is compacted in layers during filling, and the compaction work and compaction degree are large, resulting in uneven distribution of soil strength. Third, the shrinkage trend of the sample near the two ends is restricted under the action of tension. In addition to tension, it is also affected by shear force. It is a complex stress area, not a strict tensile state. Therefore, the sample is first damaged at the end when it is tensile. Due to the influence of the sample's own weight, the sample's damage surface is mostly at the upper end. Therefore, the data measured by this method cannot represent the true tensile strength of the sample.

[0003] Traditional variable diameter cutting instruments all use manual soil cutting discs. Their structure is that a rotating disc is installed on the upper and lower parts of a fixed frame. When preparing samples, the soil sample is placed between the two discs and clamped, and then the fixed soil sample disc is rotated. The sample preparer needs to use a soil cutting knife or a wire saw to perform manual cutting or cutting at a constant speed. There are the following problems in the sample preparation process:

[0004] (1) The soil cutting type is single, and cylindrical soil samples can be cut, but variable diameter soil samples cannot be cut;

[0005] (2) The manual cutting accuracy is not high, which may cause problems such as inconsistent upper and lower diameters of the soil sample, non-round soil samples, and soil fractures, which may easily cause the sample to fail;

[0006] (3) Since the structures of different types of soil are different, soil cutting at a constant speed will inevitably increase the disturbance of the soil sample;

[0007] (4) When the water content of the soil is low, the loess is hard or hard plastic. When using a soil cutter to cut the soil, it is difficult to cut it with little force. If too much force is used, it is easy to cause the soil sample to break (or partially fall off). When the water content of the soil is high, the loess is in a plastic state and its strength is greatly reduced. When cutting the soil, if the force is uneven, it is easy to cause the soil sample to twist or partially cut excessively.

[0008] Reference may be made to CN 107941586 A: Clay is filled in three layers along the axial direction of a cylindrical soil sample in a mold, and each filled layer is compacted. At the same time, reinforcing ribs are inserted at the ends of each layer of the soil sample to strengthen the strength of the end of the layer, so that the contact surface of the soil sample layers is parallel to the direction of the applied tension. The method of the present invention achieves the goal of obtaining the true value of the tensile strength of the soil sample by strengthening the strength of the sample end and eliminating the strength defects of the sample in the tensile direction.

[0009] CN 2935121 Y: The invention is composed of a fixed frame, a soil cutting disc with a fixed needle, a soil cutting disc connecting vertical shaft, a cutting frame guide shaft, a cutting frame positioning shaft, a cutting frame support platform, and a cutting frame. The cutting frame can be rotated and is easy to load and unload. When cutting soil samples, a wire saw or a soil cutting knife is used to closely contact the two vertical columns of the cutting frame, and the soil sample is carefully cut from top to bottom, and the cutting frame is rotated while cutting until the soil sample is cut to a specified diameter. Utility Model Content

[0010] The utility model aims to solve the problems in the prior art by providing a variable diameter cutting instrument for preparing soil samples for geotechnical tensile tests.

[0011] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a variable diameter cutting instrument for preparing soil samples for geotechnical tensile test, comprising a base plate, a clamp guide rail and a cutting guide rail are respectively installed on the top surface of the base plate, and a first movable seat matching therewith is installed on the clamp guide rail, and a movable clamp is rotatably connected to the first movable seat, a fixed seat is welded on the right side of the top surface of the base plate, and a fixed clamp is rotatably connected to the fixed seat, and a first pulley is installed on the rotating shaft of the fixed clamp, a motor is fixedly installed on one side of the top surface of the base plate by bolts, a second movable seat matching therewith is arranged on the cutting guide rail, and a fixed platform is arranged on the second movable seat, and a cutting knife is installed on the fixed platform, and a stepping handwheel and a stepping electronic ruler are also installed on one side of the fixed platform.

[0012] As a preferred technical solution of the utility model, a second pulley is installed at the output end of the motor, and the second pulley installed at the output end of the motor is connected to the first pulley installed on the rotating shaft of the fixing fixture through a transmission belt.

[0013] As a preferred technical solution of the present invention, a transmission is placed on the top of the base plate, and the transmission is electrically connected to the motor.

[0014] As a preferred technical solution of the utility model, the cutting knife is connected to a stepping hand wheel, and the cutting knife moves back and forth through the stepping hand wheel, and the moving distance of the cutting knife is determined by a stepping electronic ruler.

[0015] As a preferred technical solution of the utility model, a switch is installed on one side of the bottom plate, and the switch can control the motor.

[0016] As a preferred technical solution of the present utility model, a rotating hand wheel is installed at one end of the rotating shaft of the fixing fixture.

[0017] As a preferred technical solution of the present utility model, a guide rail ruler is provided on the fixture guide rail.

[0018] Compared with the prior art, the utility model provides a variable diameter cutting instrument for preparing soil samples for geotechnical tensile test, which has the following beneficial effects:

[0019] (1) The electric and manual modes can be switched freely to reduce the disturbance of soil samples during a single cutting process;

[0020] (2) High dimensional control accuracy. The measurement system is used for dimensional control. The accuracy of the stepping electronic ruler is <0.01mm, so the dimensional control of the soil sample is relatively strict;

[0021] (3) The instrument can be controlled by a sample preparation program. When preparing samples, different cutting tools can be used in combination with different cutting methods to cut soils with different structures.

[0022] (4) Applicable to different types of tensile tests, such as triaxial tensile test, transverse direct tensile test, and vertical direct tensile test;

[0023] (5) Easy to operate, different cutting rates can be used, and soils with different structures can be cut. The instrument can be controlled to complete the cutting process by simply calling the corresponding speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0025] Figure 2 This is a schematic diagram of the structure of the stepping electronic ruler of the utility model.

[0026] Figure numerals: 1. cutting tool; 2. motor; 3. transmission; 4. rotating hand wheel; 5. stepping hand wheel; 6. stepping electronic ruler; 7. fixed fixture; 8. fixture guide rail; 9. cutting guide rail; 10. switch; 11. base plate; 12. fixed table; 13. guide rail ruler; 14. mobile fixture. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] See also Figure 1-Figure 2, In this embodiment: A variable diameter cutting instrument for preparing soil samples for geotechnical tensile test, comprising a base plate 11, a fixture guide rail 8 and a cutting guide rail 9 are respectively installed on the top surface of the base plate 11, and a first moving seat matching therewith is installed on the fixture guide rail 8, and a moving fixture 7 is rotatably connected to the first moving seat, and the moving fixture 7 moves through the fixture guide rail 8, a fixed seat is welded on the right side of the top surface of the base plate 11, and a fixed fixture 14 is rotatably connected to the fixed seat, and a first pulley is installed on the rotating shaft of the fixed fixture 14, a motor 2 is fixedly installed on one side of the top surface of the base plate 11 by bolts, a second moving seat matching therewith is provided on the cutting guide rail 9, and a fixed platform 12 is provided on the second moving seat, and a cutting knife 1 is installed on the fixed platform 12, and the cutting knife 1 moves through the cutting guide rail 9, and a stepping handwheel 5 and a stepping electronic ruler 6 are also installed on one side of the fixed platform 12, and the cutting knife 1 determines the moving distance through the stepping electronic ruler 6.

[0029] In this embodiment, a second pulley is installed at the output end of the motor 2, and the second pulley installed at the output end of the motor 2 is connected to the first pulley installed on the rotating shaft of the fixed fixture 14 through a transmission belt. A transmission 3 is placed on the top of the base plate 11, and the transmission 3 is electrically connected to the motor 2. When the fixed fixture 14 rotates, the speed can be adjusted by the transmission 3. The cutting tool 1 is connected to the stepping handwheel 5, and the cutting tool 1 moves back and forth through the stepping handwheel 5. The cutting tool 1 determines the moving distance through the stepping electronic ruler 6. A switch 10 is installed on one side of the base plate 11, and the switch 10 can control the motor 2. A rotating handwheel 4 is installed at one end of the rotating shaft of the fixed fixture 14. The fixed fixture 14 drives the bearing to rotate through the motor 2 and can also drive the bearing to rotate through the rotating handwheel 4. A guide rail ruler 13 is provided on the fixture guide rail 8.

[0030] The working principle and use process of the utility model: the variable diameter cutting instrument for preparing soil samples for geotechnical tensile test, when in use, first adjust the mobile fixture 7, gently place the soil sample between the mobile fixture 7 and the fixed fixture 14, connect the transmission 3 and the motor 2, according to the required soil sample size and the nature of the soil sample, move the guide scale 13 left and right on the cutting guide rail 9 to select a suitable cutting position, then adjust the cutting knife 1 to contact with the soil sample by rotating the stepping hand wheel 5, turn on the switch 10, select the appropriate speed for cutting through the transmission 3, determine the cutting depth through the stepping electronic scale 6, and after the soil cutting diameter reduction is completed, take out the soil sample from the mobile fixture 7 and the fixed fixture 14. If the soil sample breaks when the motor 2 rotates, the connection between the transmission 3 and the motor 2 should be disconnected, and the rotating hand wheel 4 should be used for manual rotation to complete the cutting diameter reduction. In addition, the cutting knife 1 can be freely replaced by disassembling the fixed platform 12, and the mobile fixture 7 and the fixed fixture 14 can be freely replaced according to the size of the soil sample.

[0031] Finally, it should be noted that the above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A variable diameter cutting instrument for preparing soil samples for geotechnical tensile tests, comprising a bottom plate (11), characterized in that: The top surface of the base plate (11) is respectively provided with a fixture guide rail (8) and a cutting guide rail (9), and a first movable seat matching therewith is installed on the fixture guide rail (8), and a movable fixture (7) is rotatably connected to the first movable seat, a fixed seat is welded on the right side of the top surface of the base plate (11), and a fixed fixture (14) is rotatably connected to the fixed seat, and a first pulley is installed on the rotating shaft of the fixed fixture (14), a motor (2) is fixedly installed on one side of the top surface of the base plate (11) by bolts, a second movable seat matching therewith is arranged on the cutting guide rail (9), and a fixed platform (12) is arranged on the second movable seat, and a cutting tool (1) is installed on the fixed platform (12), and a stepping hand wheel (5) and a stepping electronic ruler (6) are also installed on one side of the fixed platform (12).

2. The variable diameter cutting instrument for preparing soil samples for geotechnical tensile testing according to claim 1, characterized in that: A second pulley is installed at the output end of the motor (2), and the second pulley installed at the output end of the motor (2) is connected to the first pulley installed on the rotating shaft of the fixing fixture (14) through a transmission belt.

3. The variable diameter cutting instrument for preparing soil samples for geotechnical tensile testing according to claim 1, characterized in that: A transmission (3) is placed on the top of the base plate (11), and the transmission (3) is electrically connected to the motor (2).

4. The variable diameter cutting instrument for preparing soil samples for geotechnical tensile testing according to claim 1, characterized in that: The cutting knife (1) is connected to a stepping hand wheel (5), and the cutting knife (1) is moved forward and backward by the stepping hand wheel (5), and the moving distance of the cutting knife (1) is determined by a stepping electronic ruler (6).

5. The variable diameter cutting instrument for preparing soil samples for geotechnical tensile testing according to claim 1, characterized in that: A switch (10) is installed on one side of the bottom plate (11), and the switch (10) can control the motor (2).

6. The variable diameter cutting instrument for preparing soil samples for geotechnical tensile tests according to claim 1, characterized in that: A rotating hand wheel (4) is installed at one end of the rotating shaft of the fixing fixture (14).

7. The variable diameter cutting instrument for preparing soil samples for geotechnical tensile tests according to claim 1, characterized in that: The fixture guide rail (8) is provided with a guide rail ruler (13).

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