Variable head permeability test data automatic acquisition device

Abstract

The invention discloses an automatic data acquisition device for a variable water head permeability test. The automatic data acquisition device for the variable water head permeability test comprises a water supply device (1), a pressure measuring device (2) connected with a water outlet end of the water supply device (1), and a data acquisition and processing device (3) electrically connected with the pressure measuring device (2), the variable water head penetration test data automatic acquisition device has the following advantages: the data accuracy is improved: an automatic acquisition system can accurately acquire parameters such as water head pressure, penetrating fluid temperature and the like in real time through a photoelectric and temperature control technology, and performs data processing, so that personal errors, instrument errors and environmental errors are reduced, and the test precision is improved. And the equipment is simple in composition, low in cost, convenient to operate and easy to widely apply.

Description

Technical Field

[0001] The invention relates to the technical fields of civil engineering, water conservancy engineering and environmental geotechnical engineering, and in particular to an automatic data acquisition device for variable water head penetration test. Background Art

[0002] Permeability is the phenomenon of liquid movement in porous media, and the quantitative indicator that expresses this phenomenon is the permeability coefficient. The determination of permeability coefficient is widely used in water conservancy engineering, civil engineering, environmental geotechnical engineering and other fields. At present, the domestic permeability coefficient is mainly determined by constant head and variable head permeameters. The constant head permeameter is mainly used to test the permeability coefficient of non-cohesive soil with a large permeability coefficient, and the variable head permeameter is used to test the permeability coefficient of cohesive soil with a small permeability coefficient (such as TST-55 type). The latter is composed of upper and lower covers, sample tubes, sealing rubber rings, ring knives, upper and lower permeable stones. The entire test system consists of a head pipe, a hose, a permeation container, etc. According to the amount of seepage water or head changes, the temperature of the permeate and the permeation time, the permeability coefficient is obtained according to Darcy's law. However, since the water level change, permeate temperature, permeation time and other parameters of the head pipe need to be manually read during the test, and the permeability coefficient calculation and other work are performed, the test results are greatly affected by human factors, the error is large, and manual supervision is required, which is tedious labor. Summary of the invention

[0003] The purpose of the invention is to provide an automatic data collection device for a variable water head permeability test, which solves the problems mentioned in the background technology.

[0004] The present invention is implemented as follows: an automatic data acquisition device for a variable head permeability test, the automatic data acquisition device for a variable head permeability test comprising: a water supply device, a pressure measuring device connected to the water outlet of the water supply device, and a data acquisition processing device electrically connected to the pressure measuring device. The automatic acquisition system uses photoelectric and temperature control technologies to accurately collect parameters such as head pressure and permeate temperature in real time and perform data processing, thereby reducing human errors and improving test accuracy.

[0005] A further technical solution of the present invention is: the pressure measuring device includes: a transparent water head tube, a TST-55 variable water head permeameter connected to the water outlet end of the transparent water head tube, a sealed water container connected to the water outlet end of the TST-55 variable water head permeameter, and an industrial camera placed directly in front of the transparent water head tube. The height of the water column in the water head tube can be clearly photographed by the industrial camera through the transparent water head tube, and it is connected to the data acquisition instrument through a data cable; the three temperature sensors are respectively inserted into the liquid in the covered water supply bottle, the water head tube and the sealed water container, and are respectively connected to the data acquisition instrument through data cables.

[0006] A further technical solution of the present invention is that the transparent water head pipe is arranged on the first high-precision electronic scale, the TST-55 variable head permeameter is placed on the second high-precision electronic scale, and the sealed water container is placed on the third high-precision electronic scale. The first precision electronic scale, the second high-precision electronic scale, and the third high-precision electronic scale are all electrically connected to the data acquisition and processing device.

[0007] A further technical solution of the present invention is that the water supply device includes a fixed platform and a covered water supply bottle placed on the fixed platform. The covered water supply bottle is overall cylindrical and includes a box body, a water outlet pipe, a water inlet, and a sensor reserved hole. A scale is provided on the box body. One end of the water outlet pipe is connected to the lower side of the covered water supply bottle, and the other end is divided into two lines to connect to the water inlet of the water head pipe.

[0008] A further technical solution of the present invention is that a scale plate is provided on the side wall of the transparent water head pipe, a rubber stopper is provided at the top of the transparent water head pipe. The transparent water head pipe includes a first water inlet pipe and a second water inlet pipe. A manual water valve is provided on the first water inlet pipe, and an automatic water valve is provided on the second water inlet pipe. One is controlled by the manual water valve, and the other is controlled by the automatic water valve. The automatic water valve can control the on-off of the water flow. After closing the manual water valve, the on-off of the water flow is controlled by the automatic control system. When the water level in the water head pipe drops to the scale corresponding to the water sensor, the water valve opens to let water in; when the water level in the water head pipe rises to the scale corresponding to the water sensor, the water valve closes to stop the water inlet.

[0009] A further technical solution of the present invention is that an exhaust pipe is provided on the TST-55 variable head permeameter.

[0010] A further technical solution of the present invention is that the water outlet of the TST-55 variable head permeameter is flush with the 0 scale line of the transparent water head pipe.

[0011] A further technical solution of the present invention is that temperature sensors electrically connected to the data acquisition and processing device are provided in the covered water supply bottle, the transparent water head pipe, and the sealed water container.

[0012] A further technical solution of the present invention is that the data acquisition and processing device includes a data acquisition instrument and a computer electrically connected to the data acquisition instrument. The data acquisition instrument can collect the mass change data transmitted by the high-precision electronic scale, the temperature change data transmitted by the temperature sensor, and the moisture change data transmitted by the moisture sensor, and transmit them to the relevant database and analysis software of the computer through a USB data cable. The computer can save and analyze the mass change data, temperature change data, and moisture change data through relevant software and programs, and then accurately control the on-off of the automatic water valve (13), and accurately calculate the permeability coefficient of the specimen, and draw the change curve of the permeability coefficient with time.

[0013] Advantages of the present invention: The automatic data acquisition device for variable head permeability test of the present invention has the following advantages: Improving data accuracy: The automatic acquisition system can accurately collect parameters such as head pressure and permeate temperature in real time through optoelectronic and temperature control technologies, and perform data processing, thereby reducing human errors and improving test accuracy. Moreover, this device introduces a gravity test system, which calculates the height change of the head tube through mass change, and is less affected by the test environment, reducing instrument errors and environmental errors.

[0014] Reducing manual labor: The automatic acquisition system can achieve unattended testing, reducing cumbersome manual operations and labor intensity.

[0015] Improving efficiency: The automated data acquisition and processing system can collect, store, and process data in real time, and display it in the form of visual charts, improving work efficiency and saving labor and time costs.

[0016] Simple structure and easy to promote: On the premise of achieving the test objectives, the present invention has a simple device structure, relatively low cost, and convenient operation, making it easy to be widely applied.

[0017] Strong adaptability: The variable head permeameter is applicable to the determination of the permeability of different types of soil, such as hard cemented soil and loose soil layers.

[0018] This method greatly improves the accuracy of test data and has strong practicality in actual engineering. Description of the drawings

[0019] Figure 1 is the overall structural schematic diagram of an automatic data acquisition device for variable head permeability test provided by the present invention;

[0020] Figure 2 is the working flow chart of the data acquisition system of an automatic data acquisition device for variable head permeability test provided by the present invention;

[0021] Figure 3 is the working principle diagram of the data processing of an automatic data acquisition device for variable head permeability test provided by the present invention. Specific embodiments

[0022] The following specific examples illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0023] It should be noted that the structures, proportions, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those familiar with this technology to understand and read, and are not used to limit the conditions for the implementation of the present invention. Therefore, they do not have substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle", and "one" cited in this specification are only for the convenience of clear narration and are not used to limit the scope for the implementation of the present invention. The change or adjustment of their relative relationships, without substantial change in the technical content, should also be regarded as the scope within which the present invention can be implemented.

[0024] Example 1: Figures 1-3Shows a variable-head permeability test data automatic acquisition device, which includes: a water supply device 1, a piezometric device 2 connected to the water outlet end of the water supply device 1, and a data acquisition and processing device 3 electrically connected to the piezometric device 2. The automatic acquisition system can accurately collect parameters such as head pressure and permeate temperature in real time through optoelectronic and temperature control technologies, and perform data processing, thereby reducing human errors and improving test accuracy; the piezometric device 2 includes: a transparent water head tube 21, a TST-55 variable-head permeameter 23 connected to the water outlet end of the transparent water head tube 22, a sealed water storage container 25 connected to the water outlet end of the TST-55 variable-head permeameter, and an industrial camera 27 placed directly in front of the transparent water head tube 21. By using the industrial camera to photograph the transparent water head tube, the height of the water column in the water head tube can be clearly photographed, and it is connected to the data collector through a data line; the three temperature sensors are respectively inserted into the liquids in the covered water supply bottle, the water head tube and the sealed water storage container, and are respectively connected to the data collector through data lines; the transparent water head tube 21 is arranged on the first high-precision electronic scale 22, the TST-55 variable-head permeameter 23 is placed on the second high-precision electronic scale 24, and the sealed water storage container 25 is placed on the third high-precision electronic scale 26. The first-precision electronic scale 22, the second high-precision electronic scale 24, and the third high-precision electronic scale 26 are all electrically connected to the data acquisition and processing device 3; the water supply device includes: a fixed platform 11 and a covered water supply bottle 12 placed on the fixed platform 11. The covered water supply bottle is generally cylindrical and includes a box body, a water outlet pipe, a water inlet, and a sensor reserved hole. A scale is provided on the box body.One end of the water outlet pipe is connected to the lower side of the covered water supply bottle, and the other end is divided into two lines and connected to the water inlet of the water head pipe; the transparent water head pipe 21 is fixed on the scale plate 211, and a rubber plug is provided at the top of the transparent water head pipe 21. The transparent water head pipe 21 includes: a first water inlet pipe and a second water inlet pipe. A manual water valve is provided on the first water inlet pipe, and an automatic water valve is provided on the second water inlet pipe. One is controlled by the manual water valve, and the other is controlled by the automatic water valve; the automatic water valve can control the on-off of the water flow. After closing the manual water valve, the on-off of the water flow is controlled by the automatic control system. When the water level in the water head pipe drops to the scale corresponding to the water level sensor, the water valve opens to let water in; when the water level in the water head pipe rises to the scale corresponding to the water level sensor, the water valve closes to stop the water inlet; an exhaust pipe 231 is provided on the TST-55 variable head permeameter 23; the water outlet of the TST-55 variable head permeameter 23 is flush with the 0 scale line of the transparent water head pipe 21; temperature sensors electrically connected to the data acquisition and processing device 3 are provided in the covered water supply bottle 12, the transparent water head pipe 21, and the sealed water container 25; the data acquisition and processing device 3 includes: a data acquisition instrument 31 and a computer 32 electrically connected to the data acquisition instrument 31. The data acquisition instrument can collect the mass change data transmitted by the high-precision electronic scale, the temperature change data transmitted by the temperature sensor, and the water content change data transmitted by the water content sensor, and transmit them to the relevant database and analysis software of the computer through the USB data cable. The computer can save and analyze the mass change data, temperature change data, and water content change data through relevant software and programs, and then accurately control the opening and closing of the automatic water valve 13, and accurately calculate the permeability coefficient of the specimen and draw the change curve of the permeability coefficient with time; the automatic data acquisition device for variable head permeability test of the present invention has the following advantages: improving data accuracy: the automatic acquisition system can accurately collect parameters such as water head pressure and permeate temperature in real time through optoelectronic and temperature control technologies, and perform data processing, thereby reducing human errors and improving test accuracy. And this device introduces a gravity test system, and calculates the height change of the water head pipe through the mass change, which is less affected by the test environment and can reduce instrument errors and environmental errors.

[0025] Reducing manual labor: The automatic acquisition system can realize unattended testing, reduce cumbersome manual operations, and reduce labor intensity.

[0026] Improving efficiency: The automated data acquisition and processing system can collect, store, and process data in real time and display it in the form of visual charts, improving work efficiency and saving labor costs and time costs.

[0027] Simple structure and easy to promote: On the premise of achieving the test objectives, the present invention has a simple device structure, relatively low cost, and convenient operation, and is easy to be widely applied.

[0028] Strong adaptability: The variable head permeameter is applicable to the determination of the permeability of different types of soil, such as hard cemented soil and loose soil layers.

[0029] This method greatly improves the accuracy of test data and has strong practicability in actual engineering.

[0030] The specific operation steps are as follows:

[0031] Load the soil sample into the TST-55 type variable head permeameter and seal it.

[0032] Start the computer and data acquisition device, open the manual water valves 14, 213 and 232, let the water flow fill the water head pipe and the permeameter, discharge the air in the sample and the instrument until there is stable water flowing out of the exhaust port 231, and then close the manual water valves 14 and 232.

[0033] At this time, the water flow is controlled by the moisture sensor and the automatic water valve. When the water level is 10 cm below the scale where the moisture sensor is located, the inlet water valve is automatically opened until the water level fills to the specified scale of 100 cm or 200 cm, then close the inlet water valve, and record the overall mass of the water head pipe and the plate at this moment, that is, the reading of the first high-precision electronic scale. At the same time, save the photo of the water column height of the water head pipe taken by the industrial camera 26 at this moment.

[0034] Saturate the soil sample. When the reading of the second high-precision electronic scale is basically stable, that is, when the weight of the permeameter is basically unchanged, and there is stable and continuous water flow out of the outlet, it is considered that the sample in the sampling cylinder ring knife is completely saturated. At this time, start collecting the mass change data of the first and third high-precision electronic scales at the set time interval △t, transmit it to the data acquisition instrument through the data line. At the same time, take photos of the water column height of the water head pipe at the start and end moments of this period through the industrial camera, and transmit it to the data acquisition instrument through the data line.

[0035] Record the inlet water temperature, the water temperature in the water head pipe, and the outlet water temperature of the temperature probe at the start and end of each time period respectively, and calculate the average value, which are used as the temperature measurement values t1 and t2 at the start and end of this time period respectively, and transmit them to the data acquisition instrument through the data line.

[0036] Collect information such as mass, temperature change, and pictures taken by the industrial camera through the data acquisition instrument, and transmit it to the computer software for data analysis. Combining artificial intelligence and image recognition technology, the scale value and height change value of the water column in the water head pipe can be automatically recognized.

[0037] Compare the mass changes of the first and third high-precision electronic scales. If the difference between the two is greater than 0.5 g, this set of data is discarded. If the difference between the two is less than 0.5 g, take the average value of the mass changes of the first and third high-precision electronic scales in each test period as the seepage quantity Q.

[0038] By reading the change in the readings of a high-precision electronic scale, the mass change of the water permeate in the piezometer tube can be obtained. According to the calculated inlet volume V of the variable-head permeameter is obtained, and then according to Δh is calculated, and further the height change of the water in the piezometer tube is obtained as △h = h2 - h1. Analyze the pictures taken by the industrial camera, and combine image recognition technology to obtain the change in the height of the water column in the piezometer tube. Compare and analyze it with the calculated △h. If the difference is greater than 0.1 cm, this set of data is discarded.

[0039] According to Darcy's law:

[0040]

[0041] In the formula: K t —— The permeability coefficient of the specimen at water temperature t °C, cm / s;

[0042] A—— The cross-sectional area of water permeation, cm 2 ;

[0043] Q—— The permeation amount, that is, the permeation water volume within time t, cm 3 / s;

[0044]

[0045] △t—— The time difference, s;

[0046] △t = t2 - t1

[0047] t1—— The start time of a certain test, s;

[0048] t2—— The end time of the same test, s;

[0049] i—— The hydraulic gradient, that is, the ratio of the head difference to the seepage path;

[0050]

[0051] △h—— The head difference in the piezometer tube height, cm;

[0052] △h = h2 - h1

[0053] h1—— The head height at time t1, cm;

[0054] h2—— The head height at time t2, cm;

[0055] L— The height of the specimen, cm.

[0056] Based on Darcy's law, the permeability coefficient of the specimen at water temperature t °C can be obtained.

[0057] The permeability coefficient at standard temperature can be calculated by the following formula:

[0058]

[0059] K 20 —— The permeability coefficient of the specimen at a standard water temperature of 20°C, in cm / s, calculated to two significant figures;

[0060] η t —— The dynamic viscosity coefficient of water at t°C, in kPa·s;

[0061] η 20 —— The dynamic viscosity coefficient of water at 20°C, in kPa·s;

[0062] —— The viscosity coefficient ratio.

[0063] According to the obtained permeability coefficient, a curve of the permeability coefficient changing with time can be plotted. When the permeability coefficient tends to be stable, stop data acquisition and close the inlet water valve.

[0064] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An automatic data acquisition device for variable head permeability test, characterized in that, The automatic data acquisition device for the variable-head permeability test includes: a water supply device (1), a piezometric device (2) connected to the water outlet end of the water supply device (1), and a data acquisition and processing device (3) electrically connected to the piezometric device (2).

2. The automatic data acquisition device for variable head permeability test according to claim 1, characterized in that, The piezometric device (2) includes: a transparent water head tube (21), a TST-55 variable-head permeameter (23) connected to the water outlet end of the transparent water head tube (21), a sealed water storage container (25) connected to the water outlet end of the TST-55 variable-head permeameter, and an industrial camera (27) placed directly in front of the transparent water head tube (21). The industrial camera (27) is electrically connected to the data acquisition and processing device (3).

3. The automatic data acquisition device for variable-head permeability test according to claim 2, characterized in that, The transparent water head tube (21) is arranged on a first high-precision electronic scale (22), the TST-55 variable-head permeameter (23) is placed on a second high-precision electronic scale (24), the sealed water storage container (25) is placed on a third high-precision electronic scale (26), and the first high-precision electronic scale (22), the second high-precision electronic scale (24), and the third high-precision electronic scale (26) are all electrically connected to the data acquisition and processing device (3).

4. An automatic data acquisition device for variable head permeability test according to claim 3, characterized in that, The water supply device includes: a fixed platform (11) and a covered water supply bottle (12) placed on the fixed platform (11).

5. The automatic data acquisition device for variable-head permeability test according to claim 4, characterized in that, The transparent water head tube (21) is fixed on a scale board (211), a rubber stopper (212) is provided at the top of the transparent water head tube (21), and moisture sensors electrically connected to the data acquisition and processing device (3) are provided at both the upper and lower ends of the side wall of the transparent water head tube (21). The transparent water head tube (21) includes: a first water inlet pipe, a second water inlet pipe, and a water outlet pipe. A manual water valve (14) is provided on the first water inlet pipe, an automatic water valve (13) is provided on the second water inlet pipe, and a manual water valve (213) is provided on the water outlet pipe.

6. The automatic data acquisition device for variable-head permeability test according to claim 5, characterized in that, A vent pipe (231) is provided on the TST-55 variable-head permeameter (23), and a manual water valve (232) is provided on the vent pipe.

7. An automatic data acquisition device for variable-head permeability tests according to claim 6, characterized in that, The water outlet of the TST-55 variable-head permeameter (23) is flush with the 0 scale line of the transparent water head tube (21).

8. The automatic data acquisition device for variable-head permeability test according to claim 7, characterized in that, Temperature sensors electrically connected to the data acquisition and processing device (3) are provided in the covered water supply bottle (12), the transparent water head tube (21), and the sealed water storage container (25).

9. The automatic data acquisition device for variable head permeability test according to claim 8, characterized in that, The data acquisition and processing device (3) includes: a data acquisition instrument (31) and a computer (32) electrically connected to the data acquisition instrument (31).

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