Dry-wet cycle test system and method for soil sample crack evolution test

Abstract

The invention relates to the technical field of geotechnical engineering, in particular to a dry-wet cycle test system and method for a soil sample crack evolution test, a plurality of samples are placed on a sample support according to test requirements, and in the test process, a camera above a test box is used for recording crack evolution conditions of the samples. According to the dry-wet cycle requirement, when the water content needs to be increased, a humidifier is used for discharging water vapor into the test box; when the moisture content needs to be reduced, the humidifier is closed, the electric heating wire is started, the ventilation fan is turned on, the temperature in the test box is increased, and moisture evaporation is accelerated; meanwhile, an electronic scale is adopted to measure the mass change of the sample in real time, the moisture content change in the dry-wet cycle process is calculated through computer software of a corresponding processing terminal according to the dry soil mass and the original moisture content of the sample, the test result is recorded in a computer through the computer software, and the image collection of a camera is combined to determine the moisture content of the sample. Images and data are automatically processed through computer software, and the crack change condition of the soil sample is automatically analyzed.

Description

Technical Field

[0001] The invention relates to the technical field of geotechnical engineering, and in particular to a dry-wet cycle test system and method for a soil sample crack evolution test. Background Art

[0002] In the traditional soil crack test under dry-wet cycle conditions, the dry-wet cycle of the sample needs to be carried out in a dry-wet cycle test chamber. When the sample is photographed and weighed, it needs to be moved out of the dry-wet cycle test chamber and moved to the electronic scale and camera equipment. Frequent movement can easily disturb or even damage the sample, affecting the accuracy of the test results. As the number of samples increases, the probability of disturbance and damage also increases. In addition, the amount of data that needs to be processed in the soil crack evolution test is huge, including a large amount of sample image data and temperature, humidity, and quality data, which requires a lot of manpower to process. Summary of the invention

[0003] The purpose of the present invention is to provide a dry-wet cycle test system and method for soil sample crack evolution test, aiming to solve the problems that the disturbance damage caused by frequent movement of samples in traditional soil sample crack evolution test affects the test results and the large amount of manpower required to process a large amount of test data.

[0004] To achieve the above object, the present invention provides a dry-wet cycle test method for soil sample crack evolution test, comprising the following steps:

[0005] Step 1: After the sample is prepared, place it on the sample holder of the test chamber;

[0006] Step 2: Use the equipment in the test chamber to collect images and weight data of the sample, and record the test temperature and humidity data;

[0007] Step 3: Start the humidifier or heating wire according to the dry-wet cycle requirements, and turn on or off the ventilation fan according to the test requirements;

[0008] Step 4: After the test, remove the sample from the test chamber, and the software processes the test image and test data and outputs an integrated data table.

[0009] Optionally, during the execution of step 3, when the moisture content needs to be increased, use a humidifier to discharge water vapor into the test chamber; when the moisture content needs to be reduced, turn off the humidifier, start the heating wire, turn on the ventilation fan, increase the temperature in the test chamber, and accelerate the evaporation of water; when simulating a hot and humid environment, turn on the humidifier and the heating wire at the same time.

[0010] Optionally, the process of processing the test image in step 4 includes the following steps:

[0011] Step 4.1.1: Acquire the sample image and transmit it to the processing terminal;

[0012] Step 4.1.2: Crop the sample image according to the set cropping area, keep only the sample, remove the redundant background, and save it in png format;

[0013] Step 4.1.3: Binarize the preprocessed sample image to convert the sample image from a color image to a black and white image;

[0014] Step 4.1.4: Perform corrosion operation on the binarized image to remove small connections in the image and eliminate the interference of miscellaneous items in the image;

[0015] Step 4.1.5: Calculate the number of black and white pixels in the image and their proportion to the total pixels in the image, and calculate the actual crack area based on this proportion and the actual area of ​​the sample;

[0016] Step 4.1.6: Output the sample image, the sample binarized and etched image, the sample area, the crack area, the proportion of the crack area to the test surface, and the image shooting time information.

[0017] Optionally, the process of processing the test data in step 4 includes the following steps:

[0018] Step 4.2.1: Obtain the temperature and humidity data during the test;

[0019] Step 4.2.2: Obtain sample quality data;

[0020] Step 4.2.3: Based on the initial mass and initial moisture content of the sample after preparation, combined with the mass data of the sample obtained by the electronic balance, calculate the moisture content of the sample at the moment. The calculation formula is:

[0021]

[0022] Among them, ω 初 is the initial moisture content; ω 现 is the current moisture content; m 初 is the initial sample mass; m 现 is the current sample mass;

[0023] Step 4.2.4: Draw the temperature and humidity change curves, draw the moisture content change curve over time, integrate them in a table and output them.

[0024] The present invention also proposes a dry-wet cycle test system for soil sample crack evolution test, and a dry-wet cycle test method for the soil sample crack evolution test, comprising a test box, a sample holder, a camera, a humidifier, a heating wire, an electronic scale, a data transmitter and a processing terminal, wherein the sample holder, the camera, the humidifier, the heating wire and the electronic scale are all arranged in the test box, and the camera, the humidifier, the heating wire, the electronic scale, the data transmitter and the processing terminal are electrically connected;

[0025] A plurality of sample holders are horizontally arranged in the test box, an electronic scale is arranged below each sample holder, a camera is correspondingly arranged above each sample holder, and a glass partition is arranged between the sample holder and the camera.

[0026] Among them, the sample holder includes an upper cover plate and a lower support. The top surface of the upper cover plate is set in a square shape, and a hollow cylinder is set in the center of the bottom surface of the upper cover plate. The lower support is set as a cross base, and a vertical support column is connected to the center of the cross base. The size of the support column is adapted to the hole opened in the hollow cylinder.

[0027] The test box is configured as a sealed space, with a ventilation fan disposed on the side thereof, and the ventilation fan is located in the space between the sample holder and the glass partition.

[0028] The present invention provides a dry-wet cycle test system and method for soil sample crack evolution test. According to the test requirements, multiple samples are placed on a sample holder, and during the test, a camera above the test box is used to record the crack evolution of the sample. According to the requirements of the dry-wet cycle, when the moisture content needs to be increased, a humidifier is used to discharge water vapor into the test box; when the moisture content needs to be reduced, the humidifier is turned off, the heating wire is started, the ventilation fan is turned on, the temperature in the test box is increased, and the evaporation of water is accelerated; at the same time, an electronic scale is used to measure the mass change of the sample in real time, and the computer software of the corresponding processing terminal is used to calculate the moisture content change during the dry-wet cycle based on the dry soil mass and the original moisture content of the sample. The test results are recorded in the computer through the computer software, and the image and data are automatically processed by the computer software in combination with the image collection of the camera, and the crack change of the soil sample is automatically analyzed, so as to realize intelligent testing and reduce the manpower input of test personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 The present invention is a structural schematic diagram of a dry-wet cycle test system for soil sample crack evolution test.

[0031] Figure 2 It is a schematic structural diagram of the sample holder of the present invention.

[0032] Figure 3 is a top view of the sample holder of the present invention.

[0033] Figure 4 1 is a bottom view of the sample holder of the present invention.

[0034] Figure 5 It is a top view of the upper layer of the test box of the present invention.

[0035] Figure 6 It is a schematic top view from the glass partition downward in the test box of the present invention.

[0036] Figure 7 The present invention is a schematic flow chart of a dry-wet cycle test method for soil sample crack evolution test.

[0037] 1-test box, 2-sample holder, 21-upper cover, 22-lower support, 3-camera, 4-humidifier, 5-heating wire, 6-electronic scale, 7-data transmitter, 8-processing terminal, 9-data cable, 10-glass partition, 11-ventilation fan, 12-temperature and humidity sensor. DETAILED DESCRIPTION

[0038] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0039] See also Figures 1 to 6 The present invention provides a dry-wet cycle test system for soil sample crack evolution test, comprising a test box 1, a sample holder 2, a camera 3, a humidifier 4, a heating wire 5, an electronic scale 6, a data transmitter 7 and a processing terminal 8, wherein the sample holder 2, the camera 3, the humidifier 4, the heating wire 5, and the electronic scale 6 are all arranged in the test box 1, and the camera 3, the humidifier 4, the heating wire 5, the electronic scale 6, the data transmitter 7 and the processing terminal 8 are electrically connected;

[0040] Specifically, the camera 3 , the humidifier 4 , the heating wire 5 , the electronic scale 6 and the data transmitter 7 are connected via a data line 9 to transmit corresponding information data.

[0041] A plurality of sample holders 2 are horizontally arranged in the test box 1 , an electronic scale 6 is disposed below each sample holder 2 , a camera 3 is correspondingly disposed above each sample holder 2 , and a glass partition 10 is disposed between the sample holder 2 and the camera 3 .

[0042] The sample holder 2 includes an upper cover plate 21 and a lower support 22. The top surface of the upper cover plate 21 is arranged in a square shape. A hollow cylinder is arranged at the center of the bottom surface of the upper cover plate 21. The lower support 22 is arranged as a cross base. A vertical support column is connected to the center of the cross base. The size of the support column is adapted to the hole opened in the hollow cylinder.

[0043] The test box 1 is configured as a sealed space, and a ventilation fan 11 is disposed on the side thereof. The ventilation fan 11 is located in the space between the sample holder 2 and the glass partition 10 .

[0044] Furthermore, a temperature and humidity sensor 12 is provided in the test box 1 , and the temperature and humidity sensor 12 collects temperature and humidity data inside the test box 1 , so as to facilitate the processing terminal 8 to control environmental parameters.

[0045] The following is a further description of the dry-wet cycle test method for soil sample crack evolution test:

[0046] See also Figure 7 The present invention provides a dry-wet cycle test method for soil sample crack evolution test, comprising the following steps:

[0047] S1: After the sample is prepared, place it on the sample holder of the test chamber;

[0048] S2: Use the equipment in the test chamber to collect images and weight data of the samples, and record the test temperature and humidity data;

[0049] S3: Start the humidifier or heating wire according to the dry-wet cycle requirements, and turn on or off the ventilation fan according to the test requirements;

[0050] S4: After the test, the sample is taken out of the test chamber, and the software processes the test image and test data and integrates the data table output.

[0051] Specifically, during the execution of step S3, when the moisture content needs to be increased, a humidifier is used to discharge water vapor into the test chamber; when the moisture content needs to be reduced, the humidifier is turned off, the heating wire is started, the ventilation fan is turned on, the temperature in the test chamber is increased, and the evaporation of water is accelerated; when simulating a hot and humid environment, the humidifier and the heating wire are turned on at the same time.

[0052] The process of processing the test image in step S4 includes the following steps:

[0053] ① Take the sample image through the camera on the test box, and transmit the image to the processing terminal (computer) through the data cable;

[0054] ② The software crops the sample image according to the set cropping area, retains only the sample, removes the redundant background, and saves it in png format;

[0055] ③ Binarize the sample image and convert the sample image from a color image to a black and white image;

[0056] ④Perform corrosion operation on the binarized image to remove small connections in the image and eliminate the interference of miscellaneous items in the image;

[0057] ⑤ Calculate the number of black and white pixels in the image and their proportion to the total pixels of the image, and calculate the actual crack area based on this proportion and the actual area of ​​the sample;

[0058] ⑥ Output the sample image, the sample binarized and etched image, as well as information such as the sample area, crack area, the proportion of the crack area to the test surface, and the image shooting time.

[0059] The process of processing the test data in step S4 includes the following steps:

[0060] ① Obtain the temperature and humidity data during the test through the temperature and humidity sensors on the test chamber;

[0061] ② Obtain sample mass data through the electronic balance on the test box;

[0062] ③ According to the initial mass and initial moisture content of the sample after preparation, combined with the mass data of the sample obtained by the electronic balance, calculate the moisture content of the sample at the moment. The calculation formula is:

[0063]

[0064] Where: 初 ——initial moisture content, %; ω 现 ——Current moisture content, %; m 初 ——initial sample mass, g; m 现 ——Current sample mass, g.

[0065] ④ Draw the temperature and humidity change curves, draw the moisture content change curve over time, integrate them in a table and output them.

[0066] The specific test process is as follows:

[0067] After the sample is made, it is placed on the sample holder. Multiple samples can be placed at one time for testing according to the needs. During the test, the camera above the test chamber is used to record the evolution of the cracks in the sample. According to the requirements of the dry-wet cycle, when the moisture content needs to be increased, use a humidifier to discharge water vapor into the test chamber; when the moisture content needs to be reduced, turn off the humidifier, start the heating wire, turn on the ventilation fan, increase the temperature in the test chamber, and accelerate the evaporation of water; the humidifier and the heating wire can also be turned on at the same time to simulate a hot and humid environment.

[0068] During the test, the electronic scale measures the changes in sample mass in real time. Through the corresponding computer software, the changes in moisture content during the dry-wet cycle are calculated based on the dry soil mass and original moisture content of the sample. The test results are recorded in the computer through computer software. Combined with the image collection of the camera, the computer software automatically processes the images and data, and automatically analyzes the changes in soil sample cracks, realizing intelligent testing and reducing the manpower input of test personnel.

[0069] In the traditional soil crack test under dry-wet cycle conditions, the samples need to be dry-wet cycled in a dry-wet cycle test chamber. When photographing and weighing the samples, they need to be moved out of the dry-wet cycle test chamber and moved to the electronic scale and camera equipment. The samples are easily disturbed or even damaged during the movement. The probability of being disturbed and damaged increases as the number of samples increases. In addition, the amount of soil crack evolution images and test data is large, requiring a lot of manpower to process.

[0070] In summary, the present invention has the following beneficial effects:

[0071] (1) The sample can complete the dry-wet cycle process in the test chamber and collect the changes in temperature, humidity, sample mass and crack evolution image information, avoiding disturbance and damage caused by sample movement.

[0072] (2) This system can test multiple samples at one time, realizing batch testing and reducing duplication of work.

[0073] (3) The soil crack evolution test has a large amount of experimental data, such as the changes in temperature, humidity and sample mass, crack evolution image information, etc. The data processing work is arduous. Automatic processing by computer software can greatly reduce the manpower input of test personnel.

[0074] What is disclosed above is only a preferred embodiment of the present invention, and it certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A dry-wet cycle test method for soil sample crack evolution test, characterized in that: The following steps are involved: Step 1: After the sample is prepared, place it on the sample holder of the test chamber; Step 2: Use the equipment in the test chamber to collect images and weight data of the sample, and record the test temperature and humidity data; Step 3: Start the humidifier or heating wire according to the dry-wet cycle requirements, and turn on or off the ventilation fan according to the test requirements; Step 4: After the test, remove the sample from the test chamber, and the software processes the test image and test data and outputs an integrated data table.

2. The dry-wet cycle test method for soil sample crack evolution test according to claim 1, characterized in that: During the execution of step 3, when the moisture content needs to be increased, use a humidifier to discharge water vapor into the test chamber; when the moisture content needs to be reduced, turn off the humidifier, start the heating wire, turn on the ventilation fan, increase the temperature in the test chamber, and accelerate the evaporation of water; when simulating a hot and humid environment, turn on the humidifier and the heating wire at the same time.

3. The dry-wet cycle test method for soil sample crack evolution test according to claim 1, characterized in that: The process of processing the test image in step 4 includes the following steps: Step 4.1.1: Acquire the sample image and transmit it to the processing terminal; Step 4.1.2: Crop the sample image according to the set cropping area, keep only the sample, remove the redundant background, and save it in png format; Step 4.1.3: Binarize the preprocessed sample image to convert the sample image from a color image to a black and white image; Step 4.1.4: Perform corrosion operation on the binarized image to remove small connections in the image and eliminate the interference of miscellaneous items in the image; Step 4.1.5: Calculate the number of black and white pixels in the image and their proportion to the total pixels in the image, and calculate the actual crack area based on this proportion and the actual area of ​​the sample; Step 4.1.6: Output the sample image, the sample binarized and etched image, the sample area, the crack area, the proportion of the crack area to the test surface, and the image shooting time information.

4. The dry-wet cycle test method for soil sample crack evolution test according to claim 1, characterized in that: The process of processing the test data in step 4 includes the following steps: Step 4.2.1: Obtain the temperature and humidity data during the test; Step 4.2.2: Obtain sample quality data; Step 4.2.3: Based on the initial mass and initial moisture content of the sample after preparation, combined with the mass data of the sample obtained by the electronic balance, calculate the moisture content of the sample at the moment. The calculation formula is: Among them, ω 初 is the initial moisture content; ω 现 is the current moisture content; m 初 is the initial sample mass; m 现 is the current sample mass; Step 4.2.4: Draw the temperature and humidity change curves, draw the moisture content change curve over time, integrate them in a table and output them.

5. A dry-wet cycle test system for soil sample crack evolution test, used for the dry-wet cycle test method for soil sample crack evolution test as claimed in any one of claims 1 to 4, characterized in that: It includes a test box, a sample holder, a camera, a humidifier, a heating wire, an electronic scale, a data transmitter and a processing terminal, wherein the sample holder, the camera, the humidifier, the heating wire and the electronic scale are all arranged in the test box, and the camera, the humidifier, the heating wire, the electronic scale, the data transmitter and the processing terminal are electrically connected; A plurality of sample holders are horizontally arranged in the test box, an electronic scale is arranged below each sample holder, a camera is correspondingly arranged above each sample holder, and a glass partition is arranged between the sample holder and the camera.

6. The dry-wet cycle test system for soil sample crack evolution test according to claim 5, characterized in that: The sample holder includes an upper cover plate and a lower support. The top surface of the upper cover plate is arranged in a square shape. A hollow cylinder is arranged at the center of the bottom surface of the upper cover plate. The lower support is arranged as a cross base. A vertical support column is connected to the center of the cross base. The size of the support column is adapted to the hole opened in the hollow cylinder.

7. The dry-wet cycle test system for soil sample crack evolution test according to claim 6, characterized in that: The test box is configured as a sealed space, and a ventilation fan is disposed on the side thereof. The ventilation fan is located in the space between the sample holder and the glass partition.

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