LU101322B1 - Test device for mechanical properties of interface between pile and soil - Google Patents
Test device for mechanical properties of interface between pile and soil Download PDFInfo
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- LU101322B1 LU101322B1 LU101322A LU101322A LU101322B1 LU 101322 B1 LU101322 B1 LU 101322B1 LU 101322 A LU101322 A LU 101322A LU 101322 A LU101322 A LU 101322A LU 101322 B1 LU101322 B1 LU 101322B1
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- pile
- adjustment shaft
- plate
- mechanical properties
- soil
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D33/00—Testing foundations or foundation structures
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Paleontology (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
- Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
Abstract
The present disclosure relates to the technical field of civil engineering, in particular to a test device for mechanical properties of a pile-soil contact surface. The upper ends of the two columns are fixedly connected with a top beam, and the support plate fixedly installed between the two columns is arranged below the top beam. A bottom plate provided between the two columns is fixedly installed under the support plate, and a film box is embedded between the support plate and the bottom plate. The film box includes a circular rubber film cylinder, a bottom supporting board and a cover plate. A vertical loading device for applying vertical pressure to the pile is provided at the middle of the top beam. The present disclosure can realize different experimental comparisons, by pushing the inserted bar down and fixing, pushing the bump out from the outer ring surface of the adjustment shaft via the connecting rod, thereby correspondingly increasing the diameter of the winding of the lower tensile band, so that the lower tensile band is wound more when it is rotated one turn, so as to provide greater side thrust. By changing the test method and then conducting comparative analysis, the test data is objective and accurate.
Description
SUNPT19054LU 22.07.2019 - TEST DEVICE FOR MECHANICAL PROPERTIES OF INTERFACE BETWEEN Hu101822
[0001] The present disclosure relates to the technical field of civil engineering, in particular to a test device for mechanical properties of an interface between pile and soil.
[0002] As a main form of foundation, pile foundation is widely used in foundation engineering with the accumulation of practical engineering experience and theoretical research of pile foundation engineering. The calculation formula of the pile side friction resistance given in the existing pile foundation code is mainly based on the empirical formula given the field test data. In many practical projects, the deviation of the measured side frictional resistance value is large. It is necessary to study the friction performance of pile-soil contact surface of different types of pile foundations in combination with model tests, and provide theoretical basis for pile foundation design in practical engineering.
[0003] Chinese patent application CN106769478A discloses a pile-soil contact surface test device, which comprises a circular model box, a loading plate, a counterforce beam and a servo loading motor. The device is to improve a conventional shear test device, and the column pile is placed in the soil. The lower part of the soil and the peripheral side are closed, and the upper part of the soil is pressed, and then the soil applies pressure to the pile side. However, the test device does not consider the horizontal ground pressure of the pile-soil contact surface will increased along with the depth of the pile, and the change of horizontal ground pressure will have an impact on the test results. Therefore, the frictional properties between the pile-soil contact surface simulated by the above test device and the actual pile-soil contact surface are different. _—————————————————— SS
SUNPT19054LU 22.07.2019 SUMMARY OF THE DISCLOSURE LU101322
[0004] In order to make up for the deficiencies of the prior art, the test device for the mechanical properties of the pile-soil contact surface proposed by the present disclosure can solve the problem that the existing test device does not have the simulation function when the pressure of the pile-soil contact surface increases as the depth of the pile increases.
[0005] The technical solution adopted by the present disclosure to solve the technical problem is as below: A test device for mechanical properties of a pile-soil contact surface provided by the present disclosure includes two columns. Upper ends of the two columns are together fixedly connected with a top beam, and the support plate fixedly installed between the two columns is arranged below the top beam. A bottom plate provided between the two columns is fixedly installed under the support plate, and a film box is embedded between the support plate and the bottom plate. The film box includes a circular rubber film cylinder, a bottom supporting board and a cover plate. The bottom supporting board is coaxially embedded in the middle of the bottom plate, the bottom supporting board is disposed at the lower end of the rubber film cylinder. The cover plate is used for sealing the upper port of the rubber film cylinder; the cover plate passes through the support plate and is fixedly connected to the top beam through a set of mounting posts. A vertical loading device is arranged in the middle of the top beam, the vertical loading device is used for applying vertical pressure. The pile-soil is placed in the rubber film cylinder, and a set of horizontal pressure sensors are embedded in the pile-soil;
[0006] At least a set of thrust devices are arranged on the outer periphery of the rubber film cylinder, the thrust device comprises an elastic film. Each elastic film is curved and tangent to the outer circle of the rubber film cylinder. The elastic film is provided with an adjustment shaft at each end. A slider is disposed at each of two ends of the adjustment shaft. The support plate and the bottom plate are provided with a sliding slot corresponding to the slider, and the two adjustment shafts conduct the separation movement driven by the driving device. == ——7————— SSS
SUNPT19054LU 22.07.2019
[0007] Preferably, the driving device comprises two vertical plates symmetrically mounted". 01322 on the bottom of the bottom plate. A screw is rotatably mounted between two of the vertical plates, and one end of the screw passes through one of the vertical plates and is fixedly connected to the first motor at the end. The first motor is fixedly connected with the vertical plate. The screw is oppositely disposed with a left-hand thread and a right-hand thread, wherein the slider at the lower end of one of the adjustment shafts is threaded on the left-hand thread, and the slider at the lower end of the other adjustment shaft is threaded on the right-hand thread.
[0008] Preferably, the adjustment shaft is rotatably connected to the slider. A toothed plate is disposed on one side of the sliding slot. The adjusting shaft is coaxially fixedly installed with a gear, and the gear meshes with the toothed plate.
[0009] Preferably, the elastic film is divided into an upper tensile band and a lower tensile band. The outer ring of the adjustment shaft is provided with a bump, and the bump is disposed corresponding to the lower tensile band.
[0010] Preferably, the bump is slidably installed inside the adjustment shaft. The bump is pushed out the outer ring surface of the adjustment shaft by a control device.
[0011] Preferably, the control device comprises a inserted bar, and a slot is provided inside the adjustment shaft, the inserted bar is slidably coupled in the slot, and a connecting rod is hingedly connected to the middle of the inserted bar, and the other end of the connecting rod is hingedly connected to the bump.
[0012] The advantageous effects of the present disclosure are as follows:
[0013] The present disclosure can realize different experimental comparisons, by pushing the inserted bar down and fixing, pushing the bump out from the outer ring surface of the adjustment shaft by the connecting rod, thereby correspondingly increasing the diameter of the winding of the lower tensile band, so that the lower tensile band is wound more when it is rotated one turn, so as to provide greater side thrust. By changing the test method and then conducting _—_—m _————
SUNPT19054LU 22.07.2019 comparative analysis, the test data is objective and accurate. (0101322
[0014] The present disclosure will now be further described with reference to the accompanying drawings.
[0015] Figure 1 is a schematic view of the structure of the present disclosure;
[0016] Figure 2 is a front view of the present disclosure;
[0017] Figure 3 is a cross-sectional view taken along line A-A of Figure 2;
[0018] Figure 4 is a partial enlarged view of part E in Figure 3;
[0019] Figure 5 is a cross-sectional view taken along line B-B of Figure 3;
[0020] Figure 6 is a diagram showing the connection relationship between the adjustment shaft and the lower tensile band of the present disclosure;
[0021] Figure 7 is a cross-sectional view taken along line C-C of Figure 6;
[0022] In order to make the technical means, creative features, achievement goals and effects achieved by the present disclosure easy to understand, the present disclosure will be further described below in conjunction with specific embodiments.
[0023] As shown in Figure 1 to Figure 7, a test device for mechanical properties of a pile-soil contact surface provided by the present disclosure, including two columns 15. The upper ends of the two columns 15 are fixedly connected with a top beam 11, and the support plate 12 fixedly installed between the two columns 15 is arranged below the top beam 11. A bottom plate 13 provided between the two columns 15 is fixedly installed under the support plate 12, and a film box 3 is embedded between the support plate 12 and the bottom plate 13. The film box 3 includes a circular rubber film cylinder 31, a bottom supporting board 32 and a cover plate
33. The bottom supporting board 32 is embedded in the middle of the bottom plate 13, the _—
SUNPT19054LU 22.07.2019 bottom supporting board 32 is disposed at the lower end of the rubber film cylinder 31 for 101322 blocking the lower port of the rubber film cylinder 31. The cover plate 33 is used for sealing the upper port of the rubber film cylinder 31. The cover plate 33 passes through the support plate 12 and is fixedly connected to the top beam 11 through a set of mounting posts 14. The rubber film cylinder 31 is disposed on the radially outer side of the pile 22, and when the pile column 22 is inserted into the film box 3, the rubber film cylinder 31 and the pile column 22 have a receiving cavity for accommodating the pile-soil. The pile-soil is placed in the receiving cavity, and a set of horizontal pressure sensors are embedded in the pile-soil.
[0024] A vertical loading device is disposed in the middle of the top beam 11 , and the vertical loading device is used for applying vertical pressure to the pile column 22. The vertical loading device includes a servo hydraulic machine 21 fixedly connected in the middle of the top beam 11, and the lower end of the lower pressing rod of the servo hydraulic machine 21 penetrates the top beam 11 and is in contact with the top end of the pile column 22, and the end surface of the lower pressing rod for contacting the pile column 22 is provided with a displacement sensor 23. The displacement sensor 23 is connected with the pressure sensor 24, and the pressure sensor 24 embodied disposed between the displacement sensor 23 and the pile column 22. In this structure, the servo hydraulic machine 21 applies vertical pressure to the pile column 22 via the lower pressing rod, the displacement sensor 23 is used to detect the displacement of the pile column 22, and the pressure sensor 24 is used to detect the pressure applied by the servo hydraulic machine 21 to the pile column 22, which is conventionally test means in the prior art, and here is not described in detail. At least a set of thrust devices are provided on the outer periphery of the rubber film cylinder 31. Four sets of thrust devices can be set evenly distributed in four directions of the outer ring of the rubber film cylinder 31. The thrust device includes an elastic film 41, each of the elastic film 41 is curved and tangent to the outer periphery of the rubber film cylinder 31. The elastic film 41 at each end is provided with an _—
SUNPT19054LU 22.07.2019 adjustment shaft 42. The two ends of the adjustment shaft 42 are respectively provided with FU101822 slider 43. The support plate 12 and the bottom plate 13 are provided with a sliding slot 44 corresponding to the slider 43, and the two adjustment shafts 42 are driven by the driving device to separate from each other. The driving device includes two vertical plates 51 symmetrically mounted on the bottom of the bottom plate 13, and a screw 52 is rotatably installed between the two vertical plates 51. One end of the screw 52 passes through one of the vertical plates 51 and is fixedly installed a first motor 55, and the first motor 55 is fixedly connected to the vertical plate
51. The screw 52 is oppositely disposed with a left-hand thread and a right-hand thread, and the slider 43 of the lower end of the adjustment shaft 42 is threadly connected to the left-handed thread, the slider 43 of the lower end of the other adjustment shaft 42 is threadly connected to the right-handed thread. The rotation of the screw 52 drives the two sliders 43 moving away from each other, so that the elastic film 41 on the adjustment shaft 42 is pulled, and the middle portion of the curved elastic film 41 tends to be straightened, thereby applying a thrust to the rubber film cylinder 31. A set of pressure sensors are evenly distributed in the pile-soil for collecting the horizontal thrust applied in different directions.
[0025] As an embodiment of the present disclosure, the adjustment shaft 42 is rotatably connected to the slider 43. A toothed plate 53 is disposed on one side of the sliding slot 44. A gear 54 is coaxially fixedly mounted on the adjustment shaft 42. The gear 54 meshes with the tooth plate 53. The elastic film 41 is divided into an upper tensile band 411 and a lower tensile band 412, and the outer circumference of the adjustment shaft 42 is provided with a bump 6 which is disposed corresponding to the lower tensile band 412. The bump 6 is slidably installed inside the adjustment shaft 42, the bump 6 is pushed out of the outer ring surface of the adjustment shaft 42 by the control device. The control device includes an inserted bar 7, and the adjustment shaft 42 is internally provided with a slot, the inserted bar 7 is slidably coupled in the slot. A connecting rod 71 is hingedly connected to the middle of the inserted bar 7, and the other
SUNPT19054LU 22.07.2019 end of the connecting rod 71 is hingedly connected to the bump 6, and the inserted bar 7 44107322 moved down to push the bump 6 out from the outer ring surface of adjustment shaft 42 by the connecting rod 71. As the slider 43 moves with the adjustment shaft 42, the tooth plate 53 acts on the gear 54 to drive the adjustment shaft 42 to rotate itself, and the elastic film 41 is wound around the adjustment shaft 42. If the operator simulates different side pressures of the upper and lower layers, then the inserted bar 7 is pressed down and fixed, and the bump 6 is pushed out of the outer ring surface of the adjustment shaft 42 by the connecting rod 71, thereby correspondingly increasing the diameter of the winding of the lower tensile band 412, so that the lower tensile band 412 is wound more when it is rotated one turn, so as to provide greater side thrust. By changing the test method and then conducting comparative analysis, the test data is objective and accurate.
[0026] The working principle of the present disclosure is as follows:
[0027] The tester prefabricates the pile column 22, inserts the pile column 22 into the film box 3, and after the pile-soil is loaded into the rubber film cylinder 31 and compacted, the cover plate 33 is sealed the upper port of the rubber film cylinder 31.
[0028] After the cover plate 33 is sealed, the top plate 11 is fixed on the upper end of the mounting column 14, and the servo hydraulic machine 21 is fixedly connected to the middle of the top plate 11, and the lower pressing rod of the servo hydraulic machine 21 is provided with a displacement sensor 23 on the end surface contacting the pile column 22. The pressure sensor 24 is disposed between the displacement sensor 23 and the pile column 22.
[0029] When simulating the same side pressure on one side of the pile column 22, the two sliders 43 are driven away from each other by the rotation of the screw 52, so that the elastic film 41 on the adjustment shaft 42 is pulled, and the middle portion of the curved elastic film 41 tends to be straightened, thereby a thrust is applied to the rubber film cylinder 31.
[0030] When simulating the different side pressures of the upper and lower layers on one nn“
SUNPT19054LU 22.07.2019 side of the pile column 22, the bump 6 is pushed out of the outer ring surface of the adjustment" 01322 shaft 42 through the connecting rod 71 by pressing down and fixing the inserted bar 7, thereby correspondingly making the lower drawing band The diameter of the 412 winding is increased, so that the lower tensile band 412 is wound more when the same rotation is performed, so as to provide a larger side thrust, and the comparison test is performed by changing the test mode, so that the test data is objective and accurate.
[0031] Finally, the servo hydraulic machine 21 is started to apply vertical pressure to the pile column 22, and under the vertical pressure, the pile column 22 moves in the vertical direction, and the pressure and displacement of the pile column 22 are obtained by the pressure sensor 24 and the displacement sensor 23, respectively. And the shear force of the pile-soil contact surface is calculated according to the calculation method of the prior art.
[0032] While the present disclosure has been described by way of specific embodiments, it should be understood by the ordinary skilled person in the art that various modifications and equivalent replacement may be made to the present disclosure without departing from the scope of the present disclosure. In addition, various modifications can be made to the present disclosure according to specific situation or materials, which is not out of the scope of the present disclosure. Therefore, the present disclosure is not limited to the specific embodiments disclosed, but all the embodiments falling within the scope of the appended claims. | _—
Claims (6)
1. A test device for mechanical properties of a pile-soil contact surface, comprising two columns (15); upper ends of the two columns (15) are fixedly connected with a top beam (11) together, and the support plate (12) fixedly installed between the two columns (15) is arranged below the top beam (11); a bottom plate (13) provided between the two columns (15) is fixedly installed under the support plate (12), and a film box (3) is embedded between the support plate (12) and the bottom plate (13); the film box (3) comprises a circular rubber film cylinder (31), a bottom supporting board (32) and a cover plate (33); the bottom supporting board (32) is coaxially embedded in the middle of the bottom plate (13), the bottom supporting board (32) is disposed at the lower end of the rubber film cylinder (31), and the cover plate (33) is used for sealing the upper port of the rubber film cylinder (31); the cover plate (33) passes through the support plate (12) and is fixedly connected to the top beam (11) through a set of mounting posts (14); a vertical loading device is arranged in the middle of the top beam (11), the vertical loading device is used for applying vertical pressure; the pile-soil is placed in the rubber film cylinder (31), and a set of horizontal pressure sensors are embedded in the pile-soil; wherein at least a set of thrust devices are arranged on the outer periphery of the rubber film cylinder (31), the thrust device comprises an elastic film (41), each elastic film (41) is curved and tangent to the outer circle of the rubber film cylinder (31); the elastic film (41) is provided with an adjustment shaft (42) at each end, and a slider (43) is disposed at two ends of the adjustment shaft (42), and the support plate (12) and the bottom plate (13) are provided with a sliding slot (44) corresponding to the slider (43), and the two adjustment shafts (42) conduct the separation movement driven by the driving device.
2. The test device for mechanical properties of a pile-soil contact surface according to claim 1, wherein the driving device comprises two vertical plates (51) symmetrically mounted on the bottom of the bottom plate (13), a screw (52) is rotatably mounted between two of the vertical —_—m—m————
SUNPT19054LU 22.07.2019 plates (51), and one end of the screw (52) passes through one of the vertical plates (51) and 641071322 fixedly connected to the first motor (55) at the end, the first motor (55) is fixedly connected with the vertical plate (51), the screw (52) is oppositely disposed with a left-hand thread and a right-hand thread, wherein the slider (43) at the lower end of one of the adjustment shafts (42) is threaded on the left-hand thread, and the slider (43) at the lower end of the other adjustment shaft (42) is threaded on the right-hand thread.
3. The test device for mechanical properties of a pile-soil contact surface according to claim 2, wherein the adjustment shaft (42) is rotatably connected to the slider (43), a toothed plate (53) is disposed on one side of the sliding slot (44), and the adjusting shaft (42) is coaxially fixedly installed with a gear (54), and the gear (54) meshes with the toothed plate (53).
4. The test device for mechanical properties of a pile-soil contact surface according to claim 3, wherein the elastic film (41) is divided into an upper tensile band (411) and a lower tensile band (412); the outer ring of the adjustment shaft (42) is provided with a bump (6), and the bump (6) is disposed corresponding to the lower tensile band (412).
5. The test device for mechanical properties of a pile-soil contact surface according to claim 4, wherein the bump (6) is slidably installed inside the adjustment shaft (42), and the bump (6) is pushed out the outer ring surface of the adjustment shaft (42) by a control device.
6. The test device for mechanical properties of a pile-soil contact surface according to claim 5, wherein the control device comprises a inserted bar (7), and a slot is provided inside the adjustment shaft (42), the inserted bar (7) is slidably coupled in the slot, and a connecting rod (71) is hingedly connected to the middle of the inserted bar (7), and the other end of the connecting rod (71) is hingedly connected to the bump (6). a
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| LU101322A LU101322B1 (en) | 2019-07-22 | 2019-07-22 | Test device for mechanical properties of interface between pile and soil |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| LU101322A LU101322B1 (en) | 2019-07-22 | 2019-07-22 | Test device for mechanical properties of interface between pile and soil |
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| Publication Number | Publication Date |
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| LU101322A1 LU101322A1 (en) | 2019-11-29 |
| LU101322B1 true LU101322B1 (en) | 2020-05-05 |
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| LU101322A LU101322B1 (en) | 2019-07-22 | 2019-07-22 | Test device for mechanical properties of interface between pile and soil |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113640133A (en) * | 2021-08-11 | 2021-11-12 | 中国工程物理研究院激光聚变研究中心 | Sealing film mechanical property testing device based on expansion method |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111157367A (en) * | 2020-01-20 | 2020-05-15 | 檀俊坤 | Pile-soil contact surface mechanical property test device |
| CN112695812A (en) * | 2020-12-09 | 2021-04-23 | 山西华晋岩土工程勘察有限公司 | Pile soil composite foundation bearing capacity detection device |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4885941A (en) * | 1988-06-15 | 1989-12-12 | Regents Of The University Of Minnesota | Bi-axial geomaterial test system |
| CN106769478A (en) | 2017-01-23 | 2017-05-31 | 浙江大学 | A kind of pile-soil interface shearing test device |
| CN108444841B (en) * | 2018-06-08 | 2021-01-26 | 中南大学 | Pile-soil contact surface shearing mechanical property test method |
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2019
- 2019-07-22 LU LU101322A patent/LU101322B1/en active IP Right Grant
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113640133A (en) * | 2021-08-11 | 2021-11-12 | 中国工程物理研究院激光聚变研究中心 | Sealing film mechanical property testing device based on expansion method |
| CN113640133B (en) * | 2021-08-11 | 2024-05-07 | 中国工程物理研究院激光聚变研究中心 | Sealing film mechanical property testing device based on expansion method |
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| Publication number | Publication date |
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| LU101322A1 (en) | 2019-11-29 |
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Effective date: 20200505 |