A soil disintegration tester with two-way cooperative measurement

Abstract

The utility model discloses a kind of soil body disintegration test instruments of two-way collaborative measurement, belong to soil body disintegration technical field, its purpose is to solve the technical problem of the weight measurement error caused by weighing instrument in prior art greatly influence disintegration test result. It includes shell, disintegration test area is set in shell, motor installation area located in disintegration test area upper;Disintegration test area is provided with bottom weighing instrument, water tank placed on bottom weighing instrument, camera is set on the lateral wall of disintegration test area along the circumference of water tank;Motor installation area is provided with top weighing instrument, servo motor is set on top weighing instrument, the output shaft of servo motor is wound with lifting rope, the end of lifting rope is connected with mesh box for placing soil sample;The output shaft of servo motor rotates, mesh box is placed into water tank or mesh box is pulled out of water tank by lifting rope.

Description

Technical Field

[0001] This utility model belongs to the field of soil disintegration technology, and relates to soil disintegration testing instruments, and more particularly to a two-way collaborative measurement soil disintegration testing instrument. Background Technology

[0002] In the field of geotechnical engineering, soil disintegration instruments are frequently used to test the disintegration of cohesive soils in water, whether in teaching, research, or engineering construction. A soil disintegration instrument typically includes a float and a screen. The soil to be disintegrated is placed on the screen, which is then submerged below the water surface inside the float. The disintegration process is periodically sampled and recorded (see the specifications for geotechnical testing in hydraulic engineering SL237-008-1999 and geotechnical testing in railway engineering TB10102-2004 for details).

[0003] In existing technologies, most methods involve setting graduations on the pontoon and calculating the disintegration rate and volume of the soil by recording the graduations during disintegration tests. However, this type of disintegration apparatus has certain limitations, mainly including: inconvenient operation, low degree of automation, inaccurate data, and a waste of manpower and time.

[0004] To this end, utility model patent application number 202023195638.5 discloses a portable integrated intelligent soil disintegration device, which includes a water tank, a float and a camera. One end of the float is a weighing end, and a gravity sensor is set on the weighing end. A soil sample is hung on the gravity sensor, and the gravity sensor is also connected to a gravity sensor display screen, which is set on the side wall of the float. The camera is supported on the ground by a camera bracket, and the camera's field of view includes the entire water tank. After the water tank is filled with liquid, the float and the soil sample are immersed in the liquid in the water tank. The working principle of the disintegration apparatus is as follows: 1) The float 1 and the mesh box 8 are placed in the water tank 14, and the gravity value g0 is measured by the gravity sensor; 2) The soil sample is placed in the mesh box 8 and then placed in the water tank 14 as a whole, and the gravity value gt is measured by the gravity sensor; 3) As time t changes, the soil sample wets and disintegrates, and the total amount of soil sample on the mesh box 8 decreases, and the gravity value gm is measured by the gravity sensor; 4) The camera records the entire test process, and the gravity value is transmitted to the computer in real time. The computer plots and calculates the disintegration rate Vt=Gt / t at any time t, and the disintegration amount Gt=(gt-gm) / (gt-g0) at any time, and plots the Vt-t and Gt-t curves in real time.

[0005] Similar to the utility model patent with application number 202023195638.5, the existing technology has the following drawbacks when using an electronic scale at the top to weigh the test soil sample: 1. The top is basically a strain gauge electronic balance. Although it is small in size, it is subject to electronic drift, especially for weighing measurements of weight changes. The large creep characteristic of the strain gauge electronic balance also leads to a large weight measurement error; 2. Since there is only one electronic balance at the top, the experimenter will only know that the experiment is over, but cannot directly know whether the weight measured during the experiment is accurate; 3. Since there is only one electronic balance at the top, the data measured by the electronic balance cannot be corrected during the experiment, and the weight measurement error cannot be reduced. Based on the above points, existing technologies using weighing instruments such as electronic scales to measure the weight of soil samples in disintegration tests suffer from significant errors. These errors are also carried over into the calculation of disintegration amount and disintegration rate, leading to substantial inaccuracies in the resulting disintegration amount-time curves and disintegration rate-time curves, thus affecting the conclusions of the disintegration test. Therefore, it is necessary to provide a new disintegration testing instrument to reduce the measurement error of the actual disintegration amount of the test soil sample, improve the accuracy of the soil sample disintegration amount-time curves and disintegration rate-time curves, and ultimately enhance the accuracy of the disintegration test results. Utility Model Content

[0006] The purpose of this invention is to provide a soil disintegration test instrument with bidirectional collaborative measurement, in order to solve the technical problems of large weight measurement errors and low accuracy of disintegration test results caused by setting only a weighing instrument at the top in the prior art.

[0007] To achieve the above objectives, this utility model specifically adopts the following technical solution: A two-way collaborative measurement soil disintegration test instrument includes a shell, a disintegration test area and a motor mounting area located above the disintegration test area; a bottom weighing instrument, a water tank placed on the bottom weighing instrument, and a camera arranged around the circumference of the water tank on the side wall of the disintegration test area are arranged in the disintegration test area; a top weighing instrument and a servo motor are arranged in the motor mounting area, and a suspension rope is wound around the output shaft of the servo motor, with a mesh box for placing soil samples connected to the end of the suspension rope; The output shaft of the servo motor rotates, and the mesh box is placed into the water tank or lifted out of the water tank by a suspension rope.

[0008] Furthermore, an equipment placement area is provided below the disintegration test area inside the shell, and heat dissipation holes are provided on the bottom and / or side walls of the equipment placement area.

[0009] Furthermore, an interface is provided at the bottom of the side wall of the housing.

[0010] Furthermore, casters are installed at the four corners of the bottom surface of the housing.

[0011] The beneficial effects of this utility model are as follows: In this invention, by setting a small strain gauge electronic balance at the top and a large electromagnetic force electronic balance with a high measuring range at the bottom, two advantages are achieved: First, by comparing the changes in the readings of the two weighing instruments during the test, a preliminary judgment can be made on whether there are any abnormalities in the weighing data, thus avoiding erroneous weighing data from entering the subsequent disintegration amount calculation and curve plotting process. Second, the creep of the weighing instruments can be corrected based on the data measured by the two weighing instruments, reducing the impact of weighing errors on the disintegration test results.

[0012] This disintegration apparatus, by setting up two weighing instruments at the top and bottom, can reduce the measurement error of the actual disintegration amount of the test soil sample and improve the accuracy of the disintegration test results. Attached Figure Description

[0013] Figure 1 This is a structural schematic diagram of the present invention (the lifting rope and mesh box are not shown). Figure 2 This is a structural schematic diagram of the present invention (the lifting rope and mesh box are not shown). Figure 3 This is a cross-sectional view of the present invention; Figure 4 This is a schematic diagram showing the positions of the servo motor and the water tank in this utility model; The attached figures are labeled as follows: 1-Shell, 2-Water tank, 3-Bottom weighing instrument, 4-Camera, 5-Interface, 6-Universal wheel, 7-Servo motor, 8-Top weighing instrument, 9-Mesh box, 10-Heat dissipation hole, 11-Motor mounting area, 12-Disintegration test area, 13-Equipment placement area. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.

[0015] Therefore, all other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0016] Example 1 This embodiment provides a soil disintegration testing apparatus with bidirectional collaborative measurement, used for conducting disintegration tests on test soil samples. This bidirectional collaborative measurement refers to setting up weighing instruments at both the upper and lower positions, weighing from both directions to achieve bidirectional collaborative measurement for disintegration monitoring. Figure 1-3 As shown, the soil disintegration test apparatus includes a shell 1, which is a frame structure. Two partitions are located in the middle of the shell 1, dividing the internal space of the shell 1 from top to bottom into a motor mounting area 11, a disintegration test area 12, and an equipment placement area 13. The motor mounting area 11 is used to place and fix the servo motor 7. The disintegration test area 12 is used to place disintegration test equipment such as the water tank 2 and the mesh box 9. The equipment placement area 13 is used to place the motor's servo controller, computer host, power supply, switch, router, and various external interfaces (such as power switch interface, USB interface, and Ethernet cable interface *2).

[0017] The back panel of the motor mounting area 11 is removable. A top weighing instrument 8 is installed on the bottom plate (i.e., the upper partition) of the motor mounting area 11, and a servo motor 7 is mounted on the top weighing instrument 8 (this servo motor 7 does not refer to an adjustable height, but rather that it can move the test soil sample up and down). A suspension rope is wound around the output shaft of the servo motor 7, and this rope can pass through a through hole in the bottom plate of the motor mounting area 11 (unlabeled, but from...). Figure 2 , Figure 3 It can be seen that the position of the through hole extends into the disintegration test area 12.

[0018] The front side of the disintegration test area 12 is not equipped with a front panel, meaning the front side of the disintegration test area 12 is open. A bottom weighing device 3 is installed on the bottom plate (i.e., the partition of the second layer) of the disintegration test area 12, and a water tank 2 is installed on the bottom weighing device 3. The water tank 2 can be cylindrical or cuboid in shape. Cameras 4 are installed on the side walls of the disintegration test area 12. At least two cameras 4 are installed, arranged around the circumference of the water tank 2, with each camera 4 pointing towards the water tank 2, for photographing the area of ​​the water tank 2. A corresponding supplementary light can be installed at the position of each camera 4 to provide light and illumination for the camera 4. In addition, after the suspension rope is extended into the disintegration test area 12, the end of the suspension rope is connected to the mesh box 9, and the test soil sample can be placed in the mesh box 9; the servo motor 7 works and drives the mesh box 9 to descend and sink completely into the water tank 2 containing the test liquid. The test soil sample gradually disintegrates under the action of the test liquid in the water tank 2; after the disintegration is completed or the test time is reached, the servo motor 7 works again and lifts the mesh box 9 upward, raising the mesh box 9 and the test soil sample above the water tank 2, and stopping the disintegration.

[0019] The top weighing instrument 8 and the bottom weighing instrument 3 employ electronic scales based on different principles. If the top weighing instrument 8 is a strain gauge electronic balance, then the bottom weighing instrument 3 is an electromagnetic force electronic balance; conversely, if the top weighing instrument 8 is an electromagnetic force electronic balance, then the bottom weighing instrument 3 is a strain gauge electronic balance. In this embodiment, the top weighing instrument 8 uses a small strain gauge electronic balance, while the bottom weighing instrument 3 uses a large electromagnetic force electronic balance with a high weighing range.

[0020] The back panel of the equipment placement area 13 is removable. Heat dissipation holes 10 are provided on the bottom and / or side walls of the equipment placement area 13, allowing heat generated by the equipment placed within the area to be dissipated outwards. Furthermore, the housing 1 corresponding to the equipment placement area 13 (i.e., the bottom of the side wall of the housing 1) is provided with interfaces 5. Multiple interfaces 5 can be provided, including a power switch interface, a USB interface, and two Ethernet cable interfaces (used to distinguish between the internal network and the external network).

[0021] The four corners of the bottom surface of the shell 1 are equipped with casters 6, which can be used to move the soil disintegration test instrument conveniently and quickly.

[0022] In addition, the test instrument is not equipped with a monitor, but instead has an independent all-in-one computer outside the instrument. Other computers can also access the computer host of the disintegration instrument through the local area network to view the system screen and data in real time. The specific connections between the various hardware components within the testing instrument are as follows: 1. Servo motor 7 is electrically connected to the servo controller, which in turn is electrically connected to the computer host of the disintegration instrument via a 232-to-USB converter; 2. Top weighing device 8 is electrically connected to the computer host of the disintegration instrument via a 485-to-USB converter; 3. Bottom weighing device 3 is electrically connected to the computer host of the disintegration instrument via a 232-to-USB converter; 4. Cameras (two perspectives, left and right) record changes in the sample from both high and level angles, and are connected to a switch via a network cable. The switch is then connected to the computer host of the disintegration instrument to establish device connectivity; 5. Supplemental lighting is directly connected to the power supply and is physically switched on and off via a switch button; 6. Two Ethernet ports on the exterior of the casing are connected to the LAN and WAN ports of a router, respectively. Depending on the actual situation, the disintegration instrument can be connected to either an internal or external network. The router, switch, and computer host then form a local area network.

[0023] When using the aforementioned soil disintegration testing apparatus to conduct soil disintegration tests on test soil samples, the specific test steps are as follows: Step 1: Weigh the experimental sample; The initial weight of the soil sample is obtained by measuring its weight and volume. Initial volume ; Based on the initial weight of the test soil sample Initial volume The density of the test soil sample was calculated. .

[0024] Density of the test soil sample The calculation formula is: .

[0025] Step 2: Weigh the initial weight; Start the servo motor 7 and immerse the mesh box 9 in the water tank 2 (the mesh box 9 does not touch the bottom of the water tank 2 and is completely submerged in water). After the readings on the bottom weighing instrument 3 and the top weighing instrument 8 stabilize, measure the gravity value through the bottom weighing instrument 3. The gravity value was measured by the top weighing instrument 8. .

[0026] Step 3: Measurement of water evaporation; After initial weighing, the amount of water evaporated is measured. (Water Evaporation Measurement) During the hour, the readings of the bottom weighing instrument 3 were taken multiple times. Reading of the top weighing instrument 8 The mass-time curve of water evaporation was obtained. The creep coefficient of the top weighing instrument 8 Creep coefficient of bottom weighing instrument 3 .

[0027] During the moisture evaporation measurement, the data obtained from multiple measurements can be fitted to the readings of the bottom weighing instrument 3. Regarding the curve of change over time, and the reading of the top weighing instrument 8. The curve showing how the time changes.

[0028] As is well known, under constant environmental conditions (temperature, humidity, air pressure, area), the rate of water evaporation is... It is not constant. Its characteristics are: 1. Evaporative cooling: Evaporation (evaporation rate) The latent heat of vaporization (i.e., weight loss per unit time) is required, which leads to a decrease in water temperature. decline.

[0029] 2. Dynamic balance: water temperature From the initial temperature It gradually approaches an equilibrium temperature, namely the wet-bulb temperature. .

[0030] 3. Rate change: Evaporation rate Depends on water temperature Therefore, evaporation rate It will also asymptotically approach a slower, constant (steady-state) rate from a relatively fast initial rate. .

[0031] By integrating the above physical process (the solution to the first-order differential equation), the true weight of the tested soil sample can be obtained. Functional model: ; in, , , All represent weighting coefficients. This indicates the rate at which the system reaches wet-bulb temperature under current environmental conditions.

[0032] Using computer systems / programs (e.g.) Python, MATLAB The nonlinear least multiplication method (etc.) is used to combine the data points (t, etc.) measured during the water evaporation determination process. By fitting the above function model, the parameters can be obtained. , , , Of the four parameters obtained from the fitting, the parameter... The physical meaning is steady-state array rate This allows us to obtain the subsequent evaporation weight-time curve. .

[0033] In this step, the true weight obtained from the above fitting is given. The readings obtained by the bottom weighing instrument 3 are actually inaccurate. Therefore, the true error and true weight loss of the two weighing instruments can be calculated point by point.

[0034] True quality loss The calculation formula is: ; Calculate the true error of the bottom weighing instrument 3 point by point. The true error of the top weighing instrument 8 The specific calculation formula is as follows: ; ; According to the fitted curve , (Fitted to the simplest linear function), thus obtaining the creep coefficient. , (This creep coefficient can be used to correct the measured values ​​of the relevant weighing instruments when calculating the disintegration amount later.) in, This represents the weight of the sample at time t.

[0035] Step 4: Disintegration test; Start the servo motor 7 to lift the mesh box 9 out of the water tank 2; place the test soil sample in the center of the mesh box 9; start the servo motor 7 to immerse the mesh box 9 into the water tank 2 filled with water and completely submerge the test soil sample (the bottom of the mesh box 9 does not touch the bottom of the water tank 2).

[0036] Timing begins after the mesh box 9 is fully immersed, and the gravity values ​​measured by the bottom weighing instrument 3 and the top weighing instrument 8 at time t are recorded. , The disintegration video captured by camera 4 is obtained (camera 4 is used to capture the video of the entire disintegration test process).

[0037] Step 5: Generate experimental results; The disintegration test is completed when the predetermined test end time is reached or when the test soil sample has completely disintegrated. Based on the gravity values ​​measured by the bottom weighing instrument 3 and the top weighing instrument 8, calculate the disintegration amount at time t, and generate a trend chart of disintegration amount change and a trend chart of disintegration rate change. Select disintegration photos of different disintegration stages from the disintegration video captured by camera 4.

[0038] When calculating the disintegration amount at time t based on the gravity values ​​measured by the weighing instruments, the gravity values ​​measured by the bottom weighing instrument 3 and the top weighing instrument 8 at time t are... , The correction algorithm is as follows: First, based on the creep coefficient and the mass-time curve of water evaporation. Calculate the correction values ​​for the bottom weighing instrument 3 and the top weighing instrument 8: ; ; Based on the readings of the bottom weighing instrument 3 and the top weighing instrument 8, the disintegration amount of the test soil sample at time t can be calculated respectively: ; ; in, This represents the amount of disintegration measured by the corrected top weighing instrument 8 at time t. This represents the amount of disintegration measured by the bottom weighing instrument 3 at time t. This represents the correction value of the top weighing instrument 8 at time t. This represents the correction value of the bottom weighing instrument 3 at time t. This indicates the density of the water in tank 2.

[0039] If the difference in the disintegration amounts of the bottom weighing instrument 3 and the top weighing instrument 8 at time t is within 5%, then the average of their squares is taken as the final disintegration amount used to plot the disintegration curve. That is: like ,but ; Otherwise, if the data from the two sources differ significantly, a warning message will be issued and the data will be displayed; and the data measured at time t will be invalid, and the corresponding measurement value will not be selected to plot the trend chart of the disintegration amount (i.e., when plotting the corresponding trend chart, the data at time t will not be adopted).

[0040] The main innovation of this soil disintegration testing apparatus lies in its instrument structure. After measuring relevant data using a weighing instrument, the apparatus uses related software to obtain the final disintegration amount-time curve and disintegration rate-time curve of the test soil sample. This software program is an intelligent analysis and control system for disintegration experiments, which has been registered for computer software copyright by the inventor (software name: Intelligent Analysis and Control System for Disintegration Experiments V1.0, registration number: 2025SR1284452).

Claims

1. A soil disintegration test apparatus for bidirectional collaborative measurement, characterized in that: The device includes a housing (1), a disintegration test area (12) and a motor mounting area (11) located above the disintegration test area (12). The disintegration test area (12) is equipped with a bottom weighing instrument (3), a water tank (2) placed on the bottom weighing instrument (3), and a camera (4) arranged around the side wall of the disintegration test area (12) along the circumference of the water tank (2). The motor mounting area (11) is equipped with a top weighing instrument (8) and a servo motor (7) installed on the top weighing instrument (8). A suspension rope is wound around the output shaft of the servo motor (7), and the end of the suspension rope is connected to a mesh box (9) for placing soil samples. The output shaft of the servo motor (7) rotates, and the mesh box (9) is placed into the water tank (2) by the suspension rope or the mesh box (9) is lifted up from the water tank (2).

2. The soil disintegration test apparatus for bidirectional collaborative measurement as described in claim 1, characterized in that: Inside the shell (1), below the disintegration test area (12), there is also an equipment placement area (13), and the bottom and / or side wall of the equipment placement area (13) are provided with heat dissipation holes (10).

3. The soil disintegration test apparatus for bidirectional collaborative measurement as described in claim 1, characterized in that: An interface (5) is provided at the bottom of the side wall of the housing (1).

4. The soil disintegration test apparatus for bidirectional collaborative measurement as described in claim 1, characterized in that: Universal wheels (6) are installed at the four corners of the bottom surface of the housing (1).

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