A test device and test method for preparing ring knife samples for geotechnical tests

Abstract

The present invention discloses a test device for preparing ring knife samples in geotechnical tests, wherein a circular hole is provided in the middle of the operating platform, a plurality of limit columns are provided around the circular hole to limit the sliding of the soil sample, a retainer is provided above the circular hole, a ring knife mounting hole for placing the ring knife is provided in the retainer, the ring knife mounting hole is aligned with the circular hole in the middle of the operating platform, and a lower electric push rod is provided below the circular hole; an upper electric push rod and a horizontal electric push rod are provided on the fixed frame, the upper electric push rod is located above the operating platform, and a cross sample cutting knife aligned with the ring knife is provided at the lower end of the upper electric push rod; the horizontal electric push rod is located on one side of the retainer, and a conical flat push knife is screwed on the top of the horizontal electric push rod, and the conical flat push knife is flush with the top of the retainer to remove the residual soil on the upper surface of the ring knife. Compared with the traditional manual sample cutting method, this test device saves manpower and improves work efficiency and sample quality.

Description

Technical Field

[0001] The invention relates to the field of geotechnical engineering investigation and testing, in particular to a test device and a test method for preparing ring cutter samples for indoor geotechnical tests. Technical Background

[0002] Geotechnical engineering investigation requires drilling a certain number of undisturbed soil samples at the project site and sending them to the geotechnical laboratory for testing. Indoor geotechnical test personnel use artificial methods to make standard samples of different sizes from the undisturbed soil samples drilled in the field according to the project requirements for various tests, thereby providing the physical and mechanical properties of the strata required for engineering design and construction. Among them, the main samples are ring cutter samples, that is, a standard steel ring cutter with a diameter of 61.8mm and a height of 2mm is used to manually cut the original soil samples (diameter of 108mm, height of about 3mm) that have been divided into standard samples for use in tests such as density tests, consolidation tests, and direct shear tests. The traditional ring knife sample production has the following disadvantages: 1. A large number of ring knife samples need to be produced for indoor tests. When manual cutting is used, the production process is time-consuming and labor-intensive. 2. The quality of the ring knife samples directly determines the accuracy of the test data. It is difficult to control the cutting rate and shaking of the original soil samples by manual sample preparation, and the cutting level of different test personnel is also uneven, so the quality of the final samples is difficult to guarantee. 3. The surface flatness of the ring knife samples needs to be manually cut flat with a soil cutter or steel wire, which is not only time-consuming and labor-intensive, but also inefficient, and the flatness is also poor. 4. In the process of making ring knife samples, the excess soil outside the ring knife needs to be removed, which is generally done manually. It is time-consuming and inefficient during operation, and it is also easy to disturb the sample. 5. When making hard plastic soil samples, due to the high hardness of the soil samples, it is necessary to use a lot of force to press down the ring knife when manually cutting. If the force is uneven when pressing down, it is easy to cause irregularity and disturbance of the sample. This process is not only labor-intensive, but also the quality of the sample is poor.

[0003] In summary, the traditional method of preparing ring knife samples for geotechnical tests is not only time-consuming and laborious, but also difficult to control the quality of samples because of the manual cutting of samples. In order to improve the quality of preparing ring knife samples, improve work efficiency, and save labor costs, this device is specially invented. Summary of the invention

[0004] The purpose of the present invention is to provide a test device for preparing ring knife samples in geotechnical tests, which is easy to use, can save labor, improve work efficiency and sample production quality, and is aimed at the shortcomings existing in the traditional ring knife preparation process.

[0005] In order to achieve the above-mentioned purpose, the technical solution of the present invention is a test device for preparing ring knife samples in geotechnical tests, including a fixing frame and an operating platform, characterized in that a circular hole is provided in the middle of the operating platform, and a plurality of limit columns are arranged around the circular hole to limit the sliding of the soil sample, and a retainer is arranged above the circular hole, and a ring knife mounting hole for placing the ring knife is provided in the retainer, and the ring knife mounting hole is aligned up and down with the circular hole in the middle of the operating platform, and a lower electric push rod is arranged below the circular hole; an upper electric push rod and a horizontal electric push rod are provided on the fixing frame, the upper electric push rod is located above the operating platform, and a cross cutting knife aligned up and down with the ring knife is provided at the lower end of the upper electric push rod; the horizontal electric push rod is located on one side of the retainer, and a conical flat push knife is screwed on the top of the horizontal electric push rod, and the conical flat push knife is flush with the top of the retainer and is used to remove excess soil on the upper surface of the ring knife.

[0006] Furthermore, one end of the retainer is connected to the operating platform by a hinge shaft, and the other end is provided with a buckle hole. The operating platform is provided with a fixing buckle that cooperates with the buckle hole and is used to fix the retainer.

[0007] Furthermore, the fixing buckle includes a shell fixed on the operating platform, and a spring and a pin are arranged in the shell. When in use, the pin is pulled outward to make the pin fall out of the retainer buckle hole, and when the pin is released, the spring is reset to make the pin insert into the retainer buckle hole.

[0008] Furthermore, the cross sample cutting knife is composed of four blades distributed in a cross, which can be used to smoothly push the ring knife to cut into the soil sample, and can flatten the surface of the ring knife sample embedded with the soil sample when rotating.

[0009] Furthermore, a control cabinet is provided under the operating table, and the control cabinet is equipped with an operating panel. The operating panel is set at an inclination angle of 30-60° with the horizontal plane, and a control switch and a reset switch of the electric push rod are embedded on the operating panel.

[0010] Furthermore, the operating platform is provided with fixing frame holes for connecting and fixing the fixing frame.

[0011] Furthermore, a test method for preparing a ring cutter sample in a geotechnical test is characterized in that the method comprises the following steps:

[0012] A. Place the original soil sample between the limit columns on the operating platform, cover it with the retainer, and fix the sample on the operating platform;

[0013] B. Then put the ring knife into the round hole of the retainer, start the upper electric push rod to push the cross cutting knife downward at a uniform speed to steadily press the ring knife in the retainer into the soil sample below until it contacts the operating platform;

[0014] C. The upper electric push rod stops pressing down and then rotates, driving the cross cutting knife to scrape the remaining soil on the top surface of the ring knife;

[0015] D. The upper electric push rod moves upward to reset, and then the lower electric push rod starts to push the ring cutter sample with the soil sample embedded upward until the top surface of the ring cutter is flush with the top surface of the retainer;

[0016] E. Then the horizontal electric push rod equipped with a flat push knife is started, and the excess soil on the upper surface of the ring knife sample is pushed out of the ring knife through the flat push knife, and the surface of the ring knife sample is flattened, and then reset;

[0017] F. Then the lower electric push rod starts to move upward again, pushes the entire ring knife sample out of the retainer and stops;

[0018] G. Press the reset switch, and all electric push rods return to the starting position. Then remove the remaining soil and repeat the above steps to prepare the next ring knife sample.

[0019] This test device uses an electric push rod, a cross cutting knife, a flat push knife and a retainer to automatically cut samples, automatically flatten and automatically remove excess soil outside the ring knife. Compared with the traditional manual cutting method, it saves manpower, improves work efficiency and sample quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1-1 A front view of a device for preparing ring knife samples for geotechnical testing;

[0021] Figure 2-1 A side view of a device for preparing ring knife samples for geotechnical testing;

[0022] Figure 3 - Schematic diagram of the cross cutting knife;

[0023] Figure 4 - Schematic diagram of a tapered push knife;

[0024] Figure 5 -Top view of the operating platform;

[0025] Figure 6 -Schematic diagram of the retainer;

[0026] Figure 7 -Operating platform + retainer + original soil sample map.

[0027] The figure includes: 1-upper electric push rod; 2-fixed frame; 3-cross cutting knife; 4-retainer; 5-hinge shaft; 6-fixed buckle; 7-latch; 8-operating platform; 9-limit column; 10-spring; 11-lower electric push rod; 12-soil sample; 13-control cabinet; 14-control switch; 15-reset switch; 16-circular hole of operating platform; 17-hole of fixed frame; 18-circular hole of retainer; 19-latch hole; 20-horizontal electric push rod; 21-conical flat push knife. DETAILED DESCRIPTION

[0028] The present invention will be further described below in conjunction with the accompanying drawings.

[0029] like Figure 1 and Figure 2 The front view and side view of the test device are shown. The test device is connected to an upper electric push rod 1, a horizontal electric push rod 20 and an operating platform 8 through a fixing frame 2; the operating platform 8 is placed on a control cabinet 13, a circular hole the size of a ring knife is provided in the middle of the operating platform, a retainer 4 is provided above the circular hole, a ring knife mounting hole for placing the ring knife is provided in the retainer 4, and a ring knife can be installed in the ring knife mounting hole, a lower electric push rod 11 is provided below the operating platform, an upper electric push rod 1 is provided on the operating platform 8, a cross sample cutting knife 3 is screwed to the lower end of the upper electric push rod 1, and the ring knife 3 is on the same vertical plane as the lower electric push rod, and the ring knife can be cut by pressing the upper electric push rod 1 and the cross sample cutting knife 3 down, and the residual soil outside the ring knife can be removed when the lower electric push rod pushes the ring knife out of the ring knife mounting hole of the retainer, and the cross sample cutting knife 3 can be controlled to rotate to remove the residual soil above the soil sample; a control switch 14 and a reset switch 15 are provided on the control cabinet 13 for controlling the operation and resetting of the electric push rod. The operating platform 8 is provided with a hinge shaft 5, four limit columns 9 and a fixing buckle; the four limit columns are symmetrically embedded in the operating platform, and the middle of the limit column 9 is used to place the soil sample 12. After the retainer 4 is covered on the top, the sliding of the original soil sample can be limited; one end of the retainer 4 is connected to the operating platform 8 by the hinge shaft 5, and the other end is provided with a buckle hole, which cooperates with the fixing buckle fixed on the operating platform 8. The fixing buckle includes a shell, and a spring 10 and a pin 7 are provided in the shell. The pin is used to insert into the buckle hole of the retainer 4 to fix the retainer 4; the horizontal electric push rod 20 equipped with a conical flat push knife 21 is fixed on one side of the fixed frame 2, and the conical flat push knife 21 and the retainer 4 are in the same plane. During operation, the excess soil on the upper surface of the ring knife sample can be flattened and pushed away.

[0030] Figure 3 The cross cutting knife 3 is shown as having a diameter of 62.0 mm. The upper end is provided with a swivel interface which can be swivel-connected to the lower part of the upper electric push rod 1, and the lower end is composed of a cross-shaped blade. When descending, the ring knife can be steadily pressed into the original soil sample, and the remaining soil on the surface of the ring knife can be scraped flat when rotating.

[0031] Figure 4 Shown is a conical flat push knife 21, one end of which is provided with an optional interface that can be screwed onto the horizontal electric push rod 20, and the other end is a conical blade, the width of which is consistent with the diameter of the ring knife and is flush with the top surface of the retainer 4. When moving, it can flatten the surface of the ring knife sample and push away the excess soil on the upper part of the sample surface.

[0032] Figure 5The figure shows a top view of the operating platform, on which the operating platform 8 is provided with a fixing frame hole 17, a limiting column 9, a hinge shaft 5, an operating platform circular hole 16 and a fixing buckle 6. The fixing frame hole 17 is used for the fixing frame 2 to connect and fix the operating platform 8; there are four limiting columns 9 symmetrically embedded around the operating platform circular hole 16, with a spacing of 120.0 mm, to limit the sliding of the original soil sample; the hinge shaft 5 is used to connect the retainer; the operating platform circular hole 16 has a diameter of 62.0 mm, and has a built-in lower electric push rod 11 for pushing the ring cutter.

[0033] Figure 6 The figure shows a schematic diagram of a retainer, in which a retainer circular hole 18 with a diameter of 62.0 mm is provided in the middle of the retainer 4 for placing a ring cutter, and when the ring cutter embedded in the soil sample passes through the circular hole, the remaining soil outside the ring cutter can be removed; one end of the retainer 4 is connected to the operating platform 8 by a hinge shaft 5, and the other end is provided with a pin hole 19, and the retainer can be fixed on the operating platform 8 by inserting the pin 7, and at the same time, the original soil sample at the bottom can be fixed to prevent it from moving up and down.

[0034] Figure 7 The figure shows a schematic diagram of the operating platform, retainer and original soil sample. The limiting column 9, retainer 4 and fixing buckle 6 on the operating platform 8 can fix the original soil sample with a diameter of 108 mm on the operating platform for making ring knife samples.

[0035] When using this device to prepare the ring knife sample, put the upper electric push rod 1, the lower electric push rod 11 and the horizontal electric push rod 20 in the starting state, then place the original soil sample 12 (diameter 108mm, height about 3mm) in the limit column 9 on the operating platform, cover the retainer 4, insert the spring latch 7, and fix the sample on the operating platform 8. Then put the ring knife into the circular hole 18 of the retainer, press the control switch 14, start the upper electric push rod 1 to move downward at a uniform speed, and use the cross cutting knife 3 to steadily press the ring knife in the retainer 4 into the soil sample 12 below, until the ring knife completely enters the bottom of the soil sample to the top surface of the operating platform 8, the upper electric push rod 1 stops pressing down, and rotates, driving the cross cutting knife 3 to rotate and scrape the remaining soil on the top surface of the ring knife. After rotating 3 times, the upper electric push rod starts to move up and reset, and then the lower electric push rod 11 starts, and the top The sample of the ring knife sample embedded with the soil sample is pushed upward, and stops when the top surface of the ring knife is flush with the top surface of the retainer 4. Then the horizontal electric push rod 20 equipped with the conical flat push knife 21 is started, and the remaining soil on the upper surface of the ring knife sample is pushed to the outside of the ring knife through the conical flat push knife 21, and the sample surface is flattened, and then reset. Then the lower electric push rod 11 is started again, and the entire ring knife sample is pushed out of the retainer 4 and then stops. At this time, the prepared ring knife sample can be picked up, the outer surface of the ring knife can be wiped clean, and weighed for standby use. Press the reset switch 15, and all the electric push rods return to the starting position. After removing the remaining soil, the above steps can be repeated to prepare the next ring knife sample. If there is any abnormality in the entire sample preparation process, the control switch can be pressed to stop the movement of the electric push rod, or the reset switch can be pressed to return the electric push rod to the preset position, which is convenient for clearing the fault.

Claims

1. A test device for preparing ring knife samples in geotechnical tests, comprising a fixing frame and an operating platform, characterized in that A circular hole is provided in the middle of the operating platform, and a plurality of limit columns are arranged around the circular hole to limit the sliding of the soil sample. A retainer is arranged above the circular hole, and a ring knife mounting hole for placing the ring knife is provided in the retainer. The ring knife mounting hole is aligned with the circular hole in the middle of the operating platform up and down, and a lower electric push rod is arranged below the circular hole in the middle of the operating platform to push the ring knife sample upward; an upper electric push rod and a horizontal electric push rod are provided on the fixed frame, and the upper electric push rod is located above the operating platform. A cross sample cutting knife is provided at the lower end of the upper electric push rod, which is aligned with the ring knife up and down, and the ring knife is pressed down by the upper electric push rod and the cross sample cutting knife to cut the sample; the horizontal electric push rod is located on one side of the retainer, and a conical flat push knife is screwed on the top of the horizontal electric push rod. The conical flat push knife is flush with the top of the retainer and is used to remove excess soil on the upper surface of the ring knife. The cross sample cutting knife consists of four blades distributed in a cross. A fixed frame hole is provided on the operating platform for connecting and fixing the fixed frame.

2. The test device for preparing ring cutter samples in geotechnical tests according to claim 1, characterized in that One end of the retainer is connected to the operating platform by a hinge shaft, and the other end is provided with a buckle hole. The operating platform is provided with a fixing buckle that matches the buckle hole and is used to fix the retainer.

3. The test device for preparing ring cutter samples in geotechnical tests according to claim 2, characterized in that The fixing buckle comprises a shell fixed on the operating platform, wherein a spring and a latch are arranged in the shell. When in use, the latch is pulled outwards to make the latch fall out of the retainer buckle hole, and when the latch is released, the spring is reset to make the latch insert into the retainer buckle hole.

4. The test device for preparing ring cutter samples in geotechnical tests according to claim 1, characterized in that A control cabinet is provided under the operating table. The control cabinet is equipped with an operation panel. The operation panel is set at an inclination angle of 30 to 60 degrees with the horizontal plane. The control switch and reset switch of the electric push rod are embedded on the operation panel.

5. The test method of the test device for preparing ring knife samples in geotechnical tests according to claim 1, characterized in that The method comprises the following steps: A. Place the original soil sample between the limit columns on the operating platform, cover it with the retainer, and fix the sample on the operating platform; B. Then put the ring knife into the round hole of the retainer, start the upper electric push rod to push the cross cutting knife downward at a uniform speed to steadily press the ring knife in the retainer into the soil sample below until it contacts the operating platform; C. The upper electric push rod stops pressing down and then rotates, driving the cross cutting knife to scrape the remaining soil on the top surface of the ring knife; D. The upper electric push rod moves upward to reset, and then the lower electric push rod starts to push the ring cutter sample with the soil sample embedded upward until the top surface of the ring cutter is flush with the top surface of the retainer; E. Then the horizontal electric push rod equipped with a conical push knife is started, and the excess soil on the upper surface of the ring knife sample is pushed out of the ring knife through the conical push knife, and the surface of the ring knife sample is flattened, and then reset; F. Then the lower electric push rod starts to move upward again, pushes the entire ring knife sample out of the retainer and stops; G. Press the reset switch, and all electric push rods return to the starting position. Then remove the remaining soil and repeat the above steps to prepare the next ring knife sample.

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