Simple and practical device for measuring low-saturation hydraulic conductivity of soil by using variable head method
By designing a simple variable head method measurement device including sample ring, scale tube and assembly seat, the high cost, complex production and soil disturbance problems of existing devices when measuring soil with low water conductivity and expansive soil, the high-precision water conductivity measurement of low-cost and simple structure is achieved.
Patent Information
- Application Number
- CN202420964350.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-07
- Publication Date
- 2025-03-25
- Estimated Expiration
- 2034-05-07
AI Technical Summary
When measuring soils with low water conductivity and expansive soils, the existing variable head method measurement device has problems such as high cost, complex production and disturbance to the soil surface, which affects the measurement results.
A simple and practical device is designed, including a sample ring, a scale tube and an assembly seat. By setting up an expansion gap and a water leakage network, a simple head measurement device is formed to avoid disturbances to the soil surface and is suitable for the determination of expansive soil.
It realizes low-cost, simple structure, and is particularly suitable for the determination of expansive soil, avoids disturbances to the soil surface and improves the measurement accuracy.
Smart Images
Figure CN222671649U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of soil physics, in particular to a simple and practical device for measuring low saturated water conductivity of soil by a variable water head method. Background Art
[0002] The constant water head method is difficult to meet the measurement needs of soils with low hydraulic conductivity, and the existing variable water head method measurement devices generally have problems such as high cost and complex production, which limits the widespread use of laboratories. At the same time, the existing variable water head method measurement devices have the problem of disturbing the surface soil for measuring expansive soils, and even have to remove the expansive part, which affects the measurement of saturated hydraulic conductivity. Utility Model Content
[0003] In order to solve the above technical problems, the utility model provides a simple and practical device for measuring the low saturated hydraulic conductivity of soil by a variable water head method, which is not only low in cost but also can effectively avoid disturbance to the upper layer of the soil, and is particularly suitable for measuring the saturated hydraulic conductivity of expansive soil.
[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:
[0005] The invention discloses a simple and practical device for measuring low saturated hydraulic conductivity of soil by a variable water head method, comprising a sample ring, a graduated tube and an assembly seat. The assembly seat has an assembly cavity with two ends through, a sealing plug is arranged on the top of the assembly cavity for assembling the graduated tube, a limiting groove is arranged on the bottom of the assembly cavity, the sample ring is detachably placed in the limiting groove, and an expansion gap is arranged between the sample ring and the sealing plug, a water seepage net is arranged on the bottom of the sample ring, and a supporting leg is arranged on the bottom of the assembly seat.
[0006] Preferably, a rubber ring is provided between the sample ring and the bottom of the limiting groove.
[0007] Preferably, the rubber ring is arranged on the sample ring.
[0008] Preferably, it also includes a tightening mechanism, which includes an assembly platform provided on the supporting legs and located below the sample ring, and a tightening rod that rests on the water seepage net is screwed on the assembly platform.
[0009] Preferably, a rotatable tightening plate is provided at one end of the tightening rod that contacts the water seepage screen.
[0010] Preferably, the water seepage net comprises a fixed ring sleeved on the sample ring, two filter screens are arranged from top to bottom in the fixed ring, and there is an escape gap between the two filter screens, and the filter screen away from the sample ring cooperates with the tightening plate.
[0011] Compared with the prior art, the utility model has the following beneficial effects:
[0012] The sample ring, sealing plug, graduated tube, assembly seat and water seepage net arranged in the utility model cooperate with each other to form a simple device for measuring soil saturated hydraulic conductivity by using a variable water head method. The device has a simple structure and is easy to use. An expansion gap is formed by optimizing the layout, thereby overcoming the drawback of the existing instrument in disturbing the surface layer during the measurement of expansive soil. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a schematic diagram of the cross-sectional structure of the utility model;
[0014] Figure 2 It is a structural schematic diagram of the assembly seat of the utility model;
[0015] Figure 3 It is a structural schematic diagram of the water seepage leakage net of the utility model.
[0016] Figure symbols: 1. sample ring, 2. graduation tube, 3. assembly seat, 31. assembly cavity, 32. limit groove, 33. support leg, 4. sealing plug, 5. expansion gap, 6. water seepage net, 61. fixing ring, 62. filter screen, 63. avoidance gap, 7. rubber ring, 8. tightening mechanism, 81. assembly table, 82. tightening rod, 83. tightening plate. DETAILED DESCRIPTION
[0017] In order to make the purpose, technical solutions and advantages of the utility model more clearly understood, the utility model is further described in detail below in conjunction with embodiments and drawings. The schematic implementation manner of the utility model and its description are only used to explain the utility model and are not intended to limit the utility model.
[0018] Example 1
[0019] like Figure 1 A simple and practical device for measuring low saturated hydraulic conductivity of soil by a variable water head method is shown, comprising a sample ring 1, a graduated tube 2 and an assembly seat 3. The assembly seat 3 has an assembly cavity 31 with two ends through it. A sealing plug 4 is provided on the top of the assembly cavity 31 for assembling the graduated tube 2. A limiting groove 32 is provided at the bottom of the assembly cavity 31. The sample ring 1 is detachably placed in the limiting groove 32. The setting of an expansion gap 5 allows the soil in the sample ring 1 to expand. A water seepage net 6 is provided at the bottom of the sample ring 1. A supporting leg 33 is provided at the bottom of the assembly seat 3. When measuring the saturated hydraulic conductivity of the soil, the soil to be measured that has been saturated with water is placed in the sample ring 1. The water seepage net 6 allows the water in the soil to be measured to seep out. The saturated hydraulic conductivity of the soil can be calculated by recording the liquid level information of the graduated tube 5 at the start and end of the measurement. The setting of the expansion gap 5 provides space for soil expansion, thereby overcoming the disadvantage of surface disturbance during the measurement of expansive soil.
[0020] As a preferred solution of the above embodiment, a rubber ring 7 is provided between the sample ring 1 and the bottom of the limiting groove 32 to ensure the sealing between the sample ring 1 and the limiting groove 32, thereby improving the measurement quality of the saturated hydraulic conductivity of the soil. Preferably, the rubber ring 7 is provided on the sample ring 1 to facilitate the disassembly and assembly of the rubber ring 7.
[0021] As a preferred solution of the above embodiment, in order to further improve the sealing between the sample ring 1 and the limiting groove 32, a tightening mechanism 8 is also included. The tightening mechanism 8 includes an assembly table 81 provided on the support leg 33 and located below the sample ring 1. A tightening rod 82 resting against the water seepage net 6 is screwed on the assembly table 81. When implemented, the tightening rod 82 is rotated to move toward the direction of the sample ring 1, so that the tightening rod 82 pushes the sample ring 1 to the bottom of the limiting groove 32. At this time, the rubber ring 7 is compressed and deformed, so that it can better fill the gap between the sample ring 1 and the limiting groove 32.
[0022] As a preferred solution of the above embodiment, a rotatable tightening plate 83 is provided at one end of the tightening rod 82 in contact with the water seepage net 6 to reduce the friction between the tightening rod 82 and the water seepage net 6 and avoid damage to the water seepage net 6.
[0023] As a preferred solution of the above embodiment, in order to prevent the tightening plate 83 from pushing the soil in the sample ring 1, the water seepage net 6 includes a fixed ring 61 sleeved on the sample ring 1, and two filter screens 62 are arranged from top to bottom in the fixed ring 61, and an avoidance gap 63 is provided between the two filter screens 62. The filter screen 62 away from the sample ring 1 cooperates with the tightening plate 83. Specifically, the upward force of the tightening plate 83 acts on the filter screen 62 away from the sample ring 1. The setting of the avoidance gap 63 allows the filter screen 62 away from the sample ring 1 to undergo a certain deformation without affecting the filter screen 62 close to the sample ring 1, thereby preventing the soil in the sample ring 1 from being pushed and squeezed, and at the same time ensuring that the water in the sample ring 1 can be discharged freely.
[0024] The specific steps for determining soil saturated hydraulic conductivity are as follows:
[0025] 1. Place the soil sample to be measured in the sample ring 1 and fill it with water to saturate it;
[0026] 2. Place the sample ring 1 in the limiting groove 32. A rubber ring 7 is provided at one end of the sample ring 1 close to the assembly cavity 31 to seal the contact between the sample ring 1 and the assembly cavity 31 to prevent soil and water from leaking out. A water seepage net 6 is provided at one end of the sample ring 1 away from the assembly cavity 31 to allow water in the sample ring 1 to be discharged.
[0027] 3. Insert the graduated tube 2 into the end of the assembly cavity 31 away from the sample ring 1 through the rubber stopper 4, and inject water into the assembly cavity 31 through the graduated tube 2 until the assembly cavity 31 is filled with water and the water in the graduated tube 2 has a certain height, then you can prepare to start the measurement;
[0028] 4. Record the start time of stable infiltration and the height of the graduated tube at the beginning and end;
[0029] 5. Calculate the saturated hydraulic conductivity of soil using the following formula:
[0030]
[0031] Among them, K s is the saturated hydraulic conductivity of the soil, r is the radius of the graduated tube 2, R is the diameter of the soil sample in the sample ring, L is the distance between the bottom of the sample ring and the bottom of the graduated tube, H1 is the initial water head height of the graduated tube, H2 is the water head height of the graduated tube at the end, t1 is the start time of infiltration, and t2 is the end time of infiltration.
[0032] Of course, the present invention may have many other implementation modes. Without departing from the spirit and essence of the present invention, technicians familiar with the field may make various corresponding changes and deformations based on the present invention, but these corresponding changes and deformations should all fall within the scope of protection of the claims attached to the present invention.
Claims
1. A simple and practical device for measuring low saturated hydraulic conductivity of soil by variable water head method, characterized in that: The invention comprises a sample ring (1), a graduated tube (2) and an assembly seat (3); the assembly seat (3) has an assembly cavity (31) with two ends connected therethrough; a sealing plug (4) is provided at the top of the assembly cavity (31) for assembling the graduated tube (2); a limiting groove (32) is provided at the bottom of the assembly cavity (31); the sample ring (1) is detachably placed in the limiting groove (32) and has an expansion gap (5) between the sample ring (1) and the sealing plug (4); a water seepage net (6) is provided at the bottom of the sample ring (1); and a supporting leg (33) is provided at the bottom of the assembly seat (3).
2. The simple and practical device for measuring low saturated hydraulic conductivity of soil by variable water head method according to claim 1 is characterized in that: A rubber ring (7) is provided between the sample ring (1) and the bottom of the limiting groove (32).
3. The simple and practical device for measuring low saturated hydraulic conductivity of soil by variable water head method according to claim 2 is characterized in that: The rubber ring (7) is arranged on the sample ring (1).
4. A simple and practical device for measuring low saturated hydraulic conductivity of soil by variable water head method according to any one of claims 1 to 3, characterized in that: It also includes a tightening mechanism (8), the tightening mechanism (8) including an assembly platform (81) disposed on a support leg (33) and located below the sample ring (1), the assembly platform (81) being screwed with a tightening rod (82) that abuts against the water seepage net (6).
5. The simple and practical device for measuring low saturated hydraulic conductivity of soil by variable water head method according to claim 4, characterized in that: A rotatable tightening plate (83) is provided at one end of the tightening rod (82) that contacts the water seepage net (6).
6. The simple and practical device for measuring low saturated hydraulic conductivity of soil by variable water head method according to claim 5, characterized in that: The water seepage net (6) comprises a fixing ring (61) sleeved on the sample ring (1), two filter screens (62) are arranged from top to bottom in the fixing ring (61), and an escape gap (63) is provided between the two filter screens (62), and the filter screen (62) away from the sample ring (1) cooperates with the tightening plate (83).