One-dimensional dead load consolidation test device
By designing a one-dimensional constant load subconsolidation test device, the problem of soil rebound in the nuclear magnetic resonance test was solved, and continuous test of soil samples under one-dimensional load was realized, real pore structure information was obtained, and predictive model establishment of soft clay subconsolidation deformation was supported.
Patent Information
- Application Number
- CN202422190500.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-06
- Publication Date
- 2025-07-18
- Estimated Expiration
- 2034-09-06
AI Technical Summary
The prior art cannot conduct nuclear magnetic resonance tests under the condition of maintaining one-dimensional load of soil, causing soil to rebound, affecting the accuracy of test results, and lack of consolidation devices suitable for nuclear magnetic resonance.
A one-dimensional constant load subconsolidation test device is designed, including a cylinder, a block, a limiting rod and a fixing ring. Polytetrafluoroethylene material is used to ensure that the soil sample does not rebound under load, and water is discharged through the drainage holes, so as to achieve continuous progress of soil sample consolidation and nuclear magnetic resonance test.
The soil sample has not been unloaded during subconsolidation and nuclear magnetic resonance tests, and more scientific pore structure information is obtained, which is convenient for scientific research and engineering applications.
Smart Images
Figure CN223122909U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of geotechnical engineering, and particularly relates to a one-dimensional constant-load secondary consolidation test device. Background Technique
[0002] The secondary consolidation deformation of soft clay is an important factor in the post-construction deformation of buildings, posing a great threat to the structural safety of buildings and not yet being properly solved. Revealing the evolution law of the microscopic pore structure during the secondary consolidation process of soil is the basis for establishing a prediction model for the secondary consolidation deformation of soft clay, and nuclear magnetic resonance test is considered an effective method for monitoring the pore evolution during the secondary consolidation process of soil. However, due to the particularity of the nuclear magnetic resonance test system, the conventional consolidation device cannot be directly used for nuclear magnetic resonance test, and the vertical consolidation load of the soil needs to be removed during the nuclear magnetic resonance test, which will cause the soil to rebound and affect the accuracy of the test results. Currently, there is still a lack of a device that can keep the soil under one-dimensional load for nuclear magnetic resonance test.
[0003] Therefore, the utility model designs a device that can keep the soil under vertical one-dimensional load for nuclear magnetic resonance test, ensuring that there is no unloading phenomenon during the whole process of secondary consolidation of soft clay and nuclear magnetic resonance test, and more accurately obtaining the evolution law of the pore structure during the secondary consolidation process of soft clay, providing an experimental basis for the calculation of the secondary consolidation deformation of soft clay. The utility model has important value for the development of secondary consolidation of soft clay and the design of treatment of post-construction deformation of buildings. Summary of the Invention
[0004] The utility model provides a one-dimensional constant-load secondary consolidation test device, which is simple in material, easy to obtain, low in cost, convenient to operate and easy to master. The specific scheme is as follows:
[0005] The one-dimensional constant-load secondary consolidation test device includes a cylinder with both ends open. A bottom plate is provided at the bottom end of the cylinder. A pressing block is slidably arranged in the cylinder. The top surface of the pressing block is horizontally connected with a limiting rod, and both ends of the limiting rod extend outwards to the outside of the pressing block. Limiting grooves suitable for the two ends of the limiting rod to slide are vertically opened on both sides of the cylinder. External threads are provided on the outer periphery of the upper part of the cylinder, and a fixing ring located above the limiting rod is sleeved on the external threads. A plurality of drainage holes are spacedly opened on both the pressing block and the bottom plate.
[0006] Further, there are two limiting rods at the top of the pressing block, and they are arranged perpendicular to each other. Limiting grooves suitable for the limiting rods to slide are vertically opened on the side wall of the cylinder.
[0007] Further, the limiting rod is of a rectangular structure.
[0008] Furthermore, the bottom plate is detachably arranged at the bottom end of the cylinder.
[0009] Furthermore, the cylinder body, the fixing ring, the pressing block, the limiting rod and the bottom plate are all made of polytetrafluoroethylene material.
[0010] The beneficial effects of the present utility model are as follows:
[0011] The one-dimensional constant-load secondary consolidation test device of the present utility model has the characteristics of simple and easily available materials, low cost, convenient operation, etc. This device is also easy to master, can ensure that there is no unloading phenomenon during the secondary consolidation and nuclear magnetic resonance test processes of the soil sample, obtain more scientific information on the pore structure of the soil sample, and is convenient for scientific research and engineering application. Description of the Drawings
[0012] Figure 1 is the front view of the present utility model.
[0013] Figure 2 is the front sectional view of the present utility model.
[0014] Figure 3 is the top view of the present utility model.
[0015] Description of the reference numerals: fixing ring 1, limiting rod 2, external thread 3, cylinder body 4, bottom plate 5, drainage hole 6, soil sample 7, pressing block 8. Detailed Embodiment
[0016] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments.
[0017] Refer to Figures 1-3 , the one-dimensional constant-load secondary consolidation test device includes a cylinder body 4 with both ends open. A bottom plate 5 is provided at the bottom end of the cylinder body 4. A pressing block 8 is slidably arranged in the cylinder body 4. The circumference of the pressing block 8 is in close contact with the wall of the cylinder body 4. A limiting rod 2 is horizontally connected to the top surface of the pressing block 8 and both ends thereof extend outward to the outside of the pressing block 8. Limiting grooves adapted for the sliding of both ends of the limiting rod 2 are vertically opened on both sides of the cylinder body 4. Both ends of the limiting rod 2 are flush with the outside of the limiting grooves. An external thread 3 is provided on the outer circumference of the upper part of the cylinder body 4. A fixing ring 1 located above the limiting rod 2 is sleeved on the external thread 3. When conducting the test, the pressing block 8 can be limited and fixed by the fixing ring 1. A plurality of drainage holes 6 are spaced apart on both the pressing block 8 and the bottom plate 5, facilitating the drainage of water during the secondary consolidation process of the soil sample 7 during the test.
[0018] There are two limiting rods 2 at the top of the pressing block 8 and they are arranged perpendicular to each other. Limiting grooves adapted for the sliding of the limiting rods 2 are vertically opened on the side wall of the cylinder body 4, facilitating the stability when the pressing block 8 moves downward.
[0019] The limiting rod 2 has a rectangular structure. Setting the limiting rod 2 to a rectangular structure can further ensure that it remains stable when the pressing block 8 moves downward during the test.
[0020] Preferably, the bottom plate 5 is detachably arranged at the bottom end of the cylinder body 4.
[0021] The cylinder body 4, the fixing ring 1, the pressing block 8, the limiting rod 2 and the bottom plate 5 are all made of polytetrafluoroethylene material. The manufactured parts are all thickened to ensure sufficient strength and stiffness to prevent the lateral deformation of the soil sample 7. Using polytetrafluoroethylene material can avoid affecting the magnetic field of the nuclear magnetic resonance system.
[0022] Working principle: During the one-dimensional constant load secondary consolidation test, first, tighten the bottom plate 5 to the bottom end of the cylinder body 4. Then, place the saturated soil sample 7 on the bottom plate 5 inside the cylinder body 4 and place the pressing block 8 on top of the soil sample 7. When placing the pressing block 8, the limiting rods 2 thereon are respectively placed in the corresponding limiting grooves. Then, tighten the fixing ring 1 to clamp the soil sample 7 with the pressing block. Then, place this device on a conventional consolidometer to conduct the secondary consolidation test. When conducting the nuclear magnetic resonance test on the soil sample 7, tighten the fixing ring 1. The soil sample 7 is clamped by the bottom plate 5 and the pressing block 8. At this time, the soil sample 7 will not rebound even if the consolidation load is removed. Thus, the nuclear magnetic resonance test of the soil sample 7 under the action of one-dimensional constant load can be carried out to obtain the pore change data during the secondary consolidation process of the soil sample 7. This device has simple and easily available materials, low cost, convenient operation, and is easy to master. It can ensure that there is no unloading phenomenon during the secondary consolidation and nuclear magnetic resonance test processes of the soil sample, obtain more scientific soil sample pore structure information, and facilitate scientific research and engineering applications. The specific test steps are as follows:
[0023] Step 1: Refer to Figure 1 and Figure 2 , screw the bottom plate 5 and the cylinder body 4 together. Then, place the saturated soil sample 7 on the bottom plate 5 and cover it with the pressing block 8. Then, screw the fixing ring 1 along the external thread 3 on the outside of the cylinder body 4 to limit and fix the limiting rod 2. Thus, the specimen installation is completed.
[0024] Step 2: Place this device on a conventional consolidometer, apply a vertical one-dimensional load on the pressing block 8, and conduct the secondary consolidation test of the soil sample 7. During the secondary consolidation process, the water in the soil sample 7 is discharged through the drainage holes 6 on the pressing block 8 and the bottom plate 5.
[0025] Step 3: When reaching the designed consolidation time point, tighten the fixing ring 1 along the external thread 3 on the wall of the cylinder body 4 so that the fixing ring 1 is in close contact with the limiting rod 2, and remove the vertical load on the pressing block 8. At this time, the soil sample 7 is fixed by the load provided by the bottom plate 5, the pressing block 8 and the cylinder body 4, and the soil sample 7 will not show a rebound phenomenon.
[0026] Step 4: Conduct nuclear magnetic resonance tests on the device and the soil sample 7. After the nuclear magnetic resonance tests, place the device back on the conventional consolidometer, apply the next-level load on the pressing block 8, unscrew the fixing ring 1, and continue the secondary consolidation test on the soil sample 7;
[0027] Step 5: Repeat the above Steps 2 to 4, and the secondary consolidation and nuclear magnetic resonance tests of the soil sample 7 under different loads can be completed. It is ensured that there is no unloading during the whole process of secondary consolidation → nuclear magnetic resonance test → secondary consolidation of the soil sample 7, so as to ensure that the collected pore information is true and continuous.
[0028] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention, and any reference signs in the claims should not be regarded as limiting the claims involved.
[0029] In addition, it should be understood that although this specification is described according to the embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. One-dimensional constant-load secondary consolidation test device, characterized in that: It includes a cylinder body (4) with openings at both ends. A bottom plate (5) is provided at the bottom end of the cylinder body (4). A pressing block (8) is slidably arranged in the cylinder body (4). A limiting rod (2) is horizontally connected to the top surface of the pressing block (8) and both ends thereof extend outward to the outside of the pressing block (8). Limiting grooves adapted for the sliding of both ends of the limiting rod (2) are vertically opened downward on both sides of the cylinder body (4). External threads (3) are provided on the outer periphery of the upper part of the cylinder body (4). A fixing ring (1) located above the limiting rod (2) is sleeved on the external threads (3). A plurality of drain holes (6) are spaced apart on both the pressing block (8) and the bottom plate (5).
2. The one-dimensional constant-load secondary consolidation test device according to claim 1, wherein: There are two limiting rods (2) at the top of the pressing block (8), and they are arranged perpendicular to each other. Limiting grooves adapted for the sliding of the limiting rod (2) are vertically opened downward on the side wall of the cylinder body (4).
3. The one-dimensional constant-load secondary consolidation test device according to claim 1, wherein: The limiting rod (2) has a rectangular structure.
4. The one-dimensional constant load secondary consolidation test device according to claim 1, characterized in that: The bottom plate (5) is detachably arranged at the bottom end of the cylinder body (4).
5. The one-dimensional constant-load secondary consolidation test device according to claim 1, characterized in that: The cylinder body (4), the fixing ring (1), the pressing block (8), the limiting rod (2) and the bottom plate (5) are all made of polytetrafluoroethylene material.