Test piece permeability coefficient measuring device

Abstract

The utility model relates to the technical field of test piece water permeability measurement, and discloses a test piece permeability coefficient measuring device, which comprises a water tank, a water inlet pipe, a water outlet pipe and a water outlet pipe, the test piece box is fixedly connected to the base, and the test piece box is communicated with the water tank; the measuring assembly is fixedly connected to the base, the measuring assembly is communicated with the test piece box, and water flow permeated by the test piece box passes through the measuring assembly to measure the permeability coefficient. The measuring assembly is arranged in the device, the section water head height can be rapidly measured through the measuring assembly, and the permeability coefficient of the test piece can be obtained by substituting the section water head height into a triangular weir flow measuring formula and a Darcy formula.

Description

Technical Field

[0001] The utility model relates to the technical field of test piece water permeability measurement, and more specifically, to a test piece permeability coefficient measurement device. Background Art

[0002] Since the 21st century, with the development of national economic construction and the country's strong investment in infrastructure construction, my country's engineering construction is in a golden period of vigorous development. The civil engineering industry is developing rapidly. At the same time, my country's research in the civil engineering industry has gradually deepened. There are many large and small problems in the research experiments on geotechnical and concrete. Among these problems, the permeability of concrete and geotechnical specimens has always been the focus of researchers. The permeability coefficient of the specimen is one of the key data of the research. Therefore, the measured permeability coefficient of the specimen has a very significant impact on the accuracy of the experimental results.

[0003] Currently, in order to measure the permeability coefficient of a specimen in the laboratory, the mass of water that passes through the specimen over a period of time must first be measured, and then converted into flow rate to calculate the permeability coefficient. However, the problem with this method is that during the experimental operation, the mass of the measured water will definitely be lost, which will inevitably lead to a large error, further resulting in a certain gap between the measured permeability coefficient value and the true value. In addition, this method is very troublesome and not easy to operate.

[0004] Therefore, how to enable the specimen permeability coefficient measuring device to accurately and quickly measure the specimen permeability coefficient becomes a problem that needs to be solved. Utility Model Content

[0005] The purpose of the utility model is to provide a test piece permeability coefficient measuring device to solve the problems existing in the prior art. The device is provided with a measuring component, which can quickly measure the cross-sectional water head height. The test piece permeability coefficient can be obtained by substituting the triangular weir flow measurement formula and Darcy's formula into the measuring component.

[0006] To achieve the above-mentioned purpose, the present invention provides the following solution: The present invention provides a test piece permeability coefficient measuring device, comprising: a water tank, which is installed on a base and is used to provide a water source; a test piece box, which is fixedly connected to the base and is connected to the water tank; a measuring assembly, which is fixedly connected to the base and is connected to the test piece box, and the water that has penetrated the test piece box flows through the measuring assembly to measure the permeability coefficient.

[0007] Furthermore, the measuring assembly includes: a mold; a groove, the groove is opened on the mold, one end of the groove is a closed end, and the other end is a connecting end, and the groove is connected to the specimen box; a plurality of fixing brackets, one end of the plurality of fixing brackets is fixed to the bottom of the mold, and the other end is fixed to the base.

[0008] Furthermore, a scale is provided on the side of the communication end.

[0009] Furthermore, a first opening is provided at the bottom of the test box, and a second opening is provided at the top of the test box away from the first opening. The first opening is connected to the water tank, and the second opening is connected to the groove.

[0010] Furthermore, the second opening is connected to a water pipe, and the other end of the water pipe is connected to the groove.

[0011] Furthermore, a drainage hole is provided at the bottom of the water tank, and a water pipe is connected to the drainage hole, and the other end of the water pipe is connected to the first opening.

[0012] Furthermore, a bracket is fixed on the base, and the water tank is fixed below the bracket by a steel wire.

[0013] The utility model discloses the following technical effects:

[0014] The device is provided with a water tank, a test box and a measuring component. The water in the water tank flows into the test box for penetration and is then measured by the measuring component. The water head height data can be quickly read through the measuring component. The water head height data is substituted into the triangular weir flow measurement formula and the Darcy formula to obtain the test piece permeability coefficient. This simplifies the steps required to calculate the seepage time in conventional test methods, eliminates experimental errors caused by manual reading time and the quality of non-penetrated water, and makes the experimental results more accurate. Compared with previous permeability coefficient test devices, this test device has the characteristics of easy operation, high precision and high practical application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. 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 any creative work.

[0016] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0017] Figure 2 It is a structural diagram of the measuring component in the present utility model;

[0018] Figure 3 This is a structural diagram of the test piece box in the utility model;

[0019] Figure 4 This is a schematic structural diagram of the water tank in the utility model;

[0020] Among them, 1. Base; 2. Bracket; 3. Water tank; 3.1. Drain hole; 4. Water pipe; 5. Test piece box; 5.1. First opening; 5.2. Second opening; 6. Measuring component; 6.1. Groove; 6.2. Connecting end; 6.3. Closed end; 6.4. Scale; 6.5. Fixing bracket; 7. Steel wire. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0022] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0023] like Figures 1-4 As shown, the utility model provides a test piece permeability coefficient measuring device, comprising: a water tank 3, which is mounted on a base 1 and is used to provide a water source, a water pump being installed in the water tank, and a pipe being connected to the water pump for controlling the flow of water in the water tank; a test piece box 5, which is fixedly connected to the base 1 and is communicated with the water tank 3; a measuring assembly 6, which is fixedly connected to the base 1 and is communicated with the test piece box 5, and the water flow after permeating the test piece box 5 passes through the measuring assembly 6 to measure the permeability coefficient.

[0024] A bracket 2 is welded and fixed on the base 1, and a water tank 3 is fixed below the bracket 2 by four steel wires 7. The water tank 3 is suspended in the air and filled with water to provide a constant water source to simulate the process of natural precipitation or groundwater seepage. A drainage hole 3.1 is opened at the bottom of the water tank 3, and the drainage hole 3.1 is connected to the specimen box 5 through a water pipe 4. The water in the water tank 3 flows into the specimen box 5 through the pipe.

[0025] A test box 5 is fixed to the base 1. This box is used to simulate the infiltration process under natural conditions. During use, a test specimen is placed in the box. A first opening 5.1 is defined at the bottom of the box, located on the lower left side. A pipe connects to the first opening 5.1, connecting the box 5 to the water tank 3 via the first opening 5.1, the pipe, and the drainage hole 3.1. After water enters the box 5, it permeates the specimen and flows through the gaps and cracks within it. This process can reflect the permeability characteristics of the soil or rock. A second opening 5.2 is defined at the top of the box, located on the upper right side. This second opening 5.2 serves as an overflow, maintaining a constant water head. The second opening 5.2 is connected to a pipe, the other end of which is connected to the measurement assembly 6.

[0026] The measuring assembly 6 includes a mold, a groove 6.1 and several fixing frames 6.5. The mold is a rectangular mold, and a fixing frame 6.5 is fixed under the mold. Four fixing frames 6.5 are provided, distributed at the four corners under the mold. The fixing frames 6.5 are welded and fixed to the base 1. The mold is fixed to the base 1 through the fixing frames 6.5. A groove 6.1 is provided on the mold. The groove 6.1 is a right-angled triangle groove 6.1. One end of the groove 6.1 is a closed end 6.3 to prevent water flowing into the groove 6.1 from flowing out directly, and the other end is a connecting end 6.2. A scale 6.4 is provided on the side of the connecting end 6.2 to facilitate reading the liquid level height in the groove 6.1.

[0027] Connecting end 6.2 is detachably connected to a baffle plate, which is used to adjust and control the flow rate and flow rate of the water flow, maintaining a certain liquid level within groove 6.1. This allows for more accurate measurement of flow rate and permeability coefficient, and prevents water from flowing out of groove 6.1, ensuring that the water flow forms a stable head height within the groove, thereby ensuring measurement accuracy. The baffle plate controls the path of water inflow and outflow. During the experiment, after water enters groove 6.1, due to the presence of the baffle plate, the water does not flow directly out of connecting end 6.2, but instead forms a stable liquid level within groove 6.1. This baffle plate at connecting end 6.2 ensures a stable water flow within groove 6.1, facilitating accurate measurement of water flow rate and permeability coefficient. Therefore, the baffle plate is provided to better control the water flow and ensure the accuracy and reliability of the experimental results. The detachable structure is convenient for adjustment and maintenance according to actual conditions. The detachable structure is a conventional structure. In this embodiment, a fixed groove is used to insert the acrylic transparent baffle or a snap is used for detachable connection. The baffle can be easily removed for cleaning and adjustment without affecting the overall structure and function of the device.

[0028] During the experiment, we can use a right-angled triangle thin-walled weir to measure the permeation flow of the specimen. When the flow rate to be measured is small, a right-angled triangle thin-walled weir is generally used, so that the measurement result is more accurate. The use of a triangular weir device to measure flow has a reliable theoretical basis, is easy to use, and is accurate. It is a very classic method. This experiment relies on the measurement method of a right-angled triangle thin-walled weir.

[0029] Water in the water tank 3 flows into the test box 5 through the pipe and the first opening 5.1 and passes through the test piece to simulate the infiltration process. The water that has infiltrated flows through the second opening 5.2 and the pipe and drips into the groove 6.1. The flow rate is determined by measuring the height of the water flow. When the water flows out of the groove 6.1, the water level H can be read from the scale 6.4 on the side of the triangular weir connecting end 6.2. According to the triangular weir flow rate determination formula: Where C0 is the triangular weir flow coefficient, which is generally 1.4, and then the flow is calculated, and then according to Darcy's formula but

[0030] Right now Where H0 is the seepage head difference, that is, the height difference between the water tank and the groove, which can be obtained by measuring the water level difference between the water tank and the groove. L is the length of the seepage path, and H is the head height of the triangular weir. The head height is read by the scale and the relevant data is substituted into The permeability coefficient of the specimen can be directly obtained.

[0031] The experimental data obtained by using the measurement method of the traditional device and the measurement method of the device in this application for different specimens are as follows:

[0032]

[0033] According to the data in the table, for the traditional experimental method of measuring the permeability coefficient, as the permeability coefficient of the specimen increases, the standard deviation of its permeability coefficient also gradually increases. The reason is that the traditional experimental method obtains the permeability flow by testing the permeable water mass, and when the specimen has a large permeability coefficient, the experimenter must read the water mass at the end of the test time. The large flow rate will lead to inaccurate readings, thereby generating a large error, which is manifested as the standard deviation increasing with the increase of the permeability coefficient of the specimen. In contrast, the standard deviation of the permeability coefficient measured by the test device proposed in this embodiment is basically stable in a range (0.022-0.043) as the permeability coefficient of the specimen increases. The reason is that this method is less affected by the change of the permeability coefficient of the specimen itself. Secondly, the standard deviation of the permeability coefficient measured by the test device proposed in this embodiment is smaller than the standard deviation of the permeability coefficient measured by the traditional experimental method, indicating that the numerical value measured by this method is more accurate. Therefore, it can be considered that the device for accurately measuring the permeability coefficient of a specimen proposed in this utility model is more accurate than the traditional device in measuring the permeability coefficient, and is not affected by the factors of the specimen itself.

[0034] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention.

[0035] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements to the technical solutions of the present invention made by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A test piece permeability coefficient measuring device, characterized in that: include: A water tank (3), the water tank (3) being mounted on the base (1) and being used to provide a water source; A test box (5), the test box (5) is fixed to the base (1), and the test box (5) is connected to the water tank (3); A measuring component (6) is fixedly connected to the base (1), the measuring component (6) is connected to the test box (5), and the water flow after permeating the test box (5) passes through the measuring component (6) to measure the permeability coefficient.

2. The test piece permeability coefficient measuring device according to claim 1, characterized in that: The measuring component (6) comprises: mold; A groove (6.1), the groove (6.1) is provided on the mold, one end of the groove (6.1) is a closed end (6.3), the other end is a connecting end (6.2), and the groove (6.1) is connected to the test piece box (5); A plurality of fixing frames (6.5), one end of each of the fixing frames (6.5) is fixedly connected to the bottom of the mold, and the other end is fixedly connected to the base (1).

3. The test piece permeability coefficient measuring device according to claim 2, characterized in that: A scale (6.4) is provided on the side of the communication end (6.2).

4. The test piece permeability coefficient measuring device according to claim 2, characterized in that: The test box (5) is provided with a first opening (5.1) at the bottom, and a second opening (5.2) is provided at the top of the test box (5) on a side facing away from the first opening (5.1); the first opening (5.1) is connected to the water tank (3), and the second opening (5.2) is connected to the groove (6.1).

5. The test piece permeability coefficient measuring device according to claim 4, characterized in that: The second opening (5.2) is connected to a water pipe (4), and the other end of the water pipe (4) is connected to the groove (6.1).

6. The test piece permeability coefficient measuring device according to claim 4, characterized in that: A drainage hole (3.1) is provided at the bottom of the water tank (3), a water pipe (4) is connected to the drainage hole (3.1), and the other end of the water pipe (4) is connected to the first opening (5.1).

7. The test piece permeability coefficient measuring device according to claim 1, characterized in that: A bracket (2) is fixed on the base (1), and the water tank (3) is fixed below the bracket (2) via a steel wire (7).

Images