CN114894606A - Device and method for testing creep property of geosynthetic material - Google Patents
Device and method for testing creep property of geosynthetic material Download PDFInfo
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- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
- G01N3/10—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces generated by pneumatic or hydraulic pressure
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- G01N2203/0071—Creep
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Abstract
The invention provides a device for testing the creep property of a geosynthetic material, which comprises: the device comprises a shell, a test box, a vertical loading device, a horizontal loading device, a clamp and a control system; the test box comprises a pair of adjustable side walls, and a test port with adjustable height is arranged on each adjustable side wall; the horizontal loading device is installed on the test bed through a support frame, a height adjusting mechanism is arranged between the horizontal loading device and the support frame, and the height adjusting mechanism is used for adjusting the height of the horizontal loading device so that the height of the horizontal loading device is consistent with that of the test port. The invention also provides a testing method based on the testing device for the creep property of the geosynthetic material, and the method realizes the simulation test of the creep property of the geosynthetic material under different soil depth conditions by adjusting the positions of the testing port and the horizontal loading device, so as to obtain more accurate and reliable creep property data, and has important guiding significance for the structural safety of reinforced soil.
Description
Technical Field
The invention belongs to the technical field of geosynthetic material performance tests, and particularly relates to a device and a method for testing the creep performance of a geosynthetic material.
Background
Geosynthetics, which are civil engineering materials, take artificially synthesized polymers (e.g., plastics, chemical fibers, synthetic rubbers) as raw materials to make different types of products, and place them inside or on the surface of the earth to reinforce or protect the earth. Creep of geosynthetics is the phenomenon in which strain increases with time while maintaining a constant stress. When the geosynthetic material is placed in a soil body, the geosynthetic material is subjected to long-term loading of the soil body to form a tensile state, and long-term accumulation of the phenomenon can affect the stability of the soil body. Creep deformation of the geosynthetic material can cause changes in internal stress of the reinforced earth structure, and further long-term stability of the reinforced earth structure is affected, so that the reinforced earth is unstable or generates excessive deformation. Therefore, predicting long-term creep of geosynthetics is very important to the safety of reinforced earth structures.
At this stage, researchers developed some devices for testing the creep properties of geosynthetics to achieve simulated testing of the creep properties of geosynthetics, however, such devices all suffer from a number of problems, including: (1) the vertically arranged clamps are influenced by gravity, so that the measuring result is inaccurate; (2) the weight loading can not meet the requirement of uniform stress of the material; (3) the equipment test is long in time consumption, large in workload, difficult to control in displacement speed adjustment and the like. The existence of the problems causes the creep performance test result to have larger deviation from the actual situation, and accurate and reliable creep performance test data cannot be obtained.
The application number 201710639007.1 discloses a test platform for testing the creep property of a geosynthetic material, which is characterized in that soil is filled in a test box, and then the geosynthetic material to be tested is placed in the soil, so as to test the creep property under the condition of soil constraint/lateral limitation. The device makes the test result more close to the real situation through the simulation to the real environment, has improved the accuracy of test.
However, the above device is only used for testing under the premise of filling a fixed amount of soil in a fixed-form test box, and can only obtain the creep property of the geotechnical material under a certain fixed condition in a limited way, and the device does not have wide applicability. In addition, more researches show that the geosynthetic material has different reinforcement effects under different depth conditions in the soil, and the geosynthetic material can be subjected to different forces to generate different creep phenomena, so that the method has important significance in measuring the creep performance of the geosynthetic material under the soil conditions of different depths.
On the basis, how to improve the creep property testing device of the existing geosynthetic material to enable the creep property testing device to be capable of testing the creep property of the geosynthetic material under different soil depth conditions so as to obtain more accurate and reliable creep property data has important guiding significance for the structural safety assessment and stability analysis of reinforced soil, and is a technical problem which needs to be solved urgently.
Disclosure of Invention
One of the purposes of the invention is to provide a device capable of testing the creep performance of the geosynthetic material under different soil depth conditions.
The invention also aims to provide a test method for simulating the creep property of the geosynthetic material under different soil depth conditions.
The technical scheme adopted by the invention for realizing one of the purposes is as follows: providing a device for testing the creep property of a geosynthetic material, comprising: the device comprises a shell, a test box, a vertical loading device, a horizontal loading device, a clamp, a temperature control assembly and a control system;
the test box is arranged on a test bed at the bottom of the shell; the test box comprises a pair of fixed side walls and a pair of adjustable side walls, and a test port with adjustable height is arranged on each adjustable side wall;
the vertical loading device is positioned above the test box, and the fixed end of the vertical loading device is arranged on a transverse frame at the top of the shell; the movable end of the vertical loading device is used for applying vertical pressure to soil in the test box;
the horizontal loading devices are positioned on two sides of a pair of adjustable side walls of the test box and are installed on the test bed through support frames; the movable end of the horizontal loading device is connected with a clamp, and the clamp is provided with a clamping jaw for clamping a geosynthetic material sample;
a height adjusting mechanism is arranged between the horizontal loading device and the supporting frame; the height adjusting mechanism is used for adjusting the height of the horizontal loading device, so that the height of the horizontal loading device is consistent with that of the test port;
the control system comprises a power supply, a displacement sensor, a tension sensor, a temperature regulator, a display screen and a control panel.
On the basis of the technical scheme, the adjustable side wall of the test box comprises an adjusting frame, a top fixing plate, a bottom fixing plate and a plurality of sliding plates;
sliding rails for the sliding plate to move are arranged on two sides of the adjusting frame; the test port is formed between adjacent sliding plates, between the sliding plate and the top fixed plate, or between the sliding plate and the bottom fixed plate by moving the sliding plates.
On the basis of the technical scheme, the test port is located at 1/4-3/4 of the height of the test box.
On the basis of the technical scheme, the fixed side wall of the test box is made of a high-strength transparent material, and the edge of the fixed side wall adjacent to the adjustable side wall is provided with a scale.
On the basis of the technical scheme, the vertical loading device is a hydraulic servo loading device and comprises a loading plate positioned at the bottom of the movable end, and the loading plate is used for applying vertical pressure to soil in the test box.
On the basis of the technical scheme, the horizontal loading device comprises a horizontal hydraulic servo device, the horizontal loading device is used for providing a preloading tension for the geosynthetic material sample, and the tension rate provided by the horizontal loading device is 0.1-50 mm/min.
On the basis of the technical scheme, the height adjusting mechanism is an electric servo telescopic rod, the fixed end of the height adjusting mechanism is installed on the top plate of the supporting frame, and the movable end of the height adjusting mechanism is connected with the horizontal loading device.
On the basis of the technical scheme, the temperature control assembly comprises a temperature control box covered outside the test box, and the temperature adjusting range in the temperature control box is-20-99 ℃.
The second technical scheme adopted for achieving the purpose of the invention is as follows: the invention provides a method for testing the creep property of a geosynthetic material, which is based on one of the purposes of the invention, and comprises the following steps:
s1, adjusting the position of the test port on the pair of adjustable side walls and the height of the horizontal loading device to enable the two to be on the same horizontal line;
s2, laying a first layer of soil to be flush with the horizontal loading device;
s3, transversely placing the geosynthetic material sample in a test box filled with soil, and clamping two ends of the geosynthetic material sample by using a clamping jaw of a clamp;
s4, laying a second layer of soil to be flush with the top of the fixed side wall;
s5, adjusting the temperature control assembly to set a test temperature, starting the vertical loading device, and applying a preset pressure to the soil in the test box;
and S6, acquiring data at regular intervals until the time required by the test is reached, and ending the test.
On the basis of the above technical solution, before the step S5, the method further includes the following steps: and applying a preloading tension to the geosynthetic material sample by using a horizontal loading device to enable the geosynthetic material sample to generate 1% of tensile strength preload, recording a tension value by using a tension sensor, and recording corresponding displacement by using a displacement sensor.
Compared with the prior art, the invention has the beneficial effects that:
(1) the invention provides a device for testing the creep property of a geosynthetic material. The horizontal loading devices arranged on two sides of the pair of adjustable side walls are connected with the supporting frame through the height adjusting mechanism, the vertical height of the horizontal loading devices can be adjusted by controlling the height adjusting mechanism, the height of the horizontal loading devices is kept consistent with that of the test port, geosynthetic material samples are placed according to the position of the test port, different amounts of soil are filled, and then the test of the creep performance of the geosynthetic material is realized under the conditions of different soil depths.
(2) According to the method for testing the creep property of the geosynthetic material, provided by the invention, the testing box with the height-adjustable testing port is utilized, and the height-adjustable horizontal loading device is matched, so that the position of the geosynthetic material in the testing box is adjusted, the tensile creep or the tensile creep fracture of the geosynthetic material under different soil depths is simulated more truly, and an effective way is provided for further researching the creep property of the geosynthetic material. In addition, through comparing the creep performance data of the geosynthetics under different depth conditions, the most suitable soil depth condition of the geosynthetics can be found out, and the method has important guiding significance for soil reinforcement operation in actual engineering.
Drawings
Fig. 1 is a schematic overall structure diagram of a device for testing creep performance of a geosynthetic material according to an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of a test box according to an embodiment of the present invention;
FIG. 3 is a top view of a test chamber provided by an embodiment of the present invention;
FIG. 4 is a schematic structural diagram of a fixing sidewall according to an embodiment of the present invention;
FIG. 5 is a schematic view of a clamp jaw configuration of a clamp provided in accordance with an embodiment of the present invention;
fig. 6 is a side view of a support stand according to an embodiment of the present invention.
Wherein, 1-shell; 11-test stand; 12-a support frame; 2-a test box; 21-fixed side wall; 212-scale; 22-adjustable side walls; 221-a conditioning frame; 222-a top fixing plate; 223-bottom fixation plate; 224-a sliding plate; 23-a test port; 3-a vertical loading device; 31-a loading plate; 4-horizontal loading means; 41-height adjusting mechanism; 5, clamping; 51-a jaw; 6-a temperature control component; 61-temperature control box.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.
The present invention is further illustrated by the following examples, which are not to be construed as limiting the invention.
Example 1
Referring to fig. 1, the present embodiment provides a device for testing the creep property of a geosynthetic material, which includes: the device comprises a shell 1, a test box 2, a vertical loading device 3, a horizontal loading device 4, a clamp 5, a temperature control assembly 6 and a control system;
the test box 2 is arranged on the test bed 11 at the bottom of the shell 1, the test box 2 comprises a pair of fixed side walls 21 and a pair of adjustable side walls 22, and the adjustable side walls 22 are provided with test ports 23 with adjustable heights; the vertical loading device 3 is positioned above the test box 2, the fixed end of the vertical loading device is installed on a transverse frame at the top of the shell 1, and the movable end of the vertical loading device is used for applying vertical pressure to soil in the test box 2; the horizontal loading devices 4 are positioned at two sides of a pair of adjustable side walls 22 of the test box 2 and are arranged on the test bed 11 through a support frame 12; the movable end of the horizontal loading device 4 is connected with a clamp 5, and the clamp 5 is provided with a clamping jaw 51 for clamping a geosynthetic material sample; a height adjusting mechanism 41 is also arranged between the horizontal loading device 4 and the support frame 12; the height adjusting mechanism 41 is used for adjusting the height of the horizontal loading device 4, so that the height of the horizontal loading device 4 is consistent with that of the test port 23.
The control system comprises a power supply, a displacement sensor, a tension sensor, a temperature regulator, a display screen and a control panel. In the present embodiment, the displacement sensor and the tension sensor are respectively disposed on two sides of the position of the horizontal loading device 4 close to the supporting frame 12. Wherein the tension sensor is used to measure tension loaded on the geosynthetic material and the displacement sensor is used to measure elongation of the geosynthetic material. The temperature regulator is used for regulating the test temperature of the temperature control component 6, and the control panel is used for regulating horizontal and vertical tension and pressure. And the signal output end of an industrial personal computer of the control system is connected with a display screen, and the display screen displays the vertical loading pressure, the horizontal loading tension and the elongation of the geosynthetic material.
According to the testing device for the creep property of the geosynthetic material, the height of the testing port 23 and the height of the horizontal loading device 4 are adjustable, and testers can adjust the position of the opening of the testing port 23 and the height of the horizontal loading device 4 according to the testing requirements of the geosynthetic material sample, so that the soil below and above the testing port can be filled, and the purpose that the geosynthetic material is placed in the soil environment with different heights of the testing box and simulation testing is performed is achieved. The testing device can simulate the creep dynamics of the geosynthetic material under different soil depths, and compared with the past testing device, the testing result of the testing device is closer to the actual engineering condition.
Referring to fig. 2 and 3, the testing box 2 of the present embodiment is a rectangular parallelepiped structure, the top of which is open, the bottom of which is closed, and the periphery of which is provided with a sidewall, and the sidewall adjacent to the horizontal loading device 4 is an adjustable sidewall 22. The adjustable side wall 22 comprises an adjustment frame 221, a top fixed plate 222, a bottom fixed plate 223 and a plurality of sliding plates 224; sliding rails for the sliding plate 224 to move are arranged on two sides of the adjusting frame 221; the test port 23 is formed between the adjacent sliding plates 224, between the sliding plates 224 and the top fixing plate 222, or between the sliding plates 224 and the bottom fixing plate 223 by moving the sliding plates 224.
In the present embodiment, the distance between the top fixing plate 222 and the bottom fixing plate 223 is an adjustable range of the opening of the test port 23. Preferably, the test port 23 is located at 1/4-3/4 of the height of the test box 2, and the height position and the opening size of the test port 23 can be adjusted by adjusting the position of the slide plate 224 (including moving the upper slide plate 224 downward, moving the lower slide plate 224 upward, or moving the upper and lower slide plates 224 simultaneously). Further, the adjusting frame 221 is provided with a sliding rail, each sliding plate 224 is slidably connected with the sliding rail through a sliding block, and each sliding block is provided with a locking button for locking the position of the sliding plate 224.
Specifically, the number and size of the sliding plates 224 can be flexibly set according to actual test requirements. In the present embodiment, the top fixing plate 222, the bottom fixing plate 223 and the sliding plate 224 have the same size, two sliding rails are respectively disposed on both sides of the adjusting frame 221, and one sliding plate 224 is disposed above and below each sliding rail (i.e., four sliding plates in total). The pair of sliding plates 224 located on the inner side are mainly used for adjusting the height position and the opening size of the test port 23, and the pair of sliding plates 224 located on the outer side play a role in auxiliary supporting, and move the sliding plates to the outer side of the joint of the fixed plate and the sliding plates 224, so that the test box 2 can be reinforced, and the overall stability of the test box 2 in the test process can be further maintained.
Referring to fig. 4, the fixed sidewall 21 of the testing box 2 is made of a high-strength transparent material, and a scale 212 is disposed at an edge of the fixed sidewall 21 adjacent to the adjustable sidewall 22. In this embodiment, the fixed side wall 21 is made of tempered glass, so that a tester can observe the test from the outside of the housing 1 conveniently. The edge of the fixed side wall 21 is provided with a scale 212, and the scale 212 is provided with scales for marking the position of the test port 23, so that the height of the sliding plate 224 can be conveniently adjusted, the opening position of the test port 23 can be controlled, and the accuracy of the simulation test can be further improved.
In the present embodiment, the height of the test cassette is 400mm, the lengths of the top fixing plate 222, the bottom fixing plate 223 and the four sliding plates 224 are all 100mm, the thickness is 10mm, and the scale range of the scale 212 is 1/4-3/4 of the height of the test cassette. In some other embodiments, the dimensions may also be adjusted according to the depth of the soil being tested and the specifications of the geosynthetic material.
Further, the vertical loading device 3 is a hydraulic servo loading device, and includes a loading plate 31 located at the bottom of the movable end, where the loading plate 31 is used to extend into the test box 2 to apply vertical pressure to soil in the test box 2, and to compact a soil body in the test box 2. The size of the load plate 31 is slightly smaller than the size of the top opening of the test chamber 2 to ensure uniform load loading.
The horizontal loading device 4 comprises a horizontal hydraulic servo device, the horizontal loading device 4 is used for providing a preloading tension for the geosynthetic material sample, and the tension rate provided by the horizontal loading device 4 is 0.1-50 mm/min.
Referring to fig. 5, the clamp 5 includes a pair of clamping jaws 51, and the clamping jaws 51 are provided with an upper clamping plate and a lower clamping plate, and the contact surfaces of the upper clamping plate and the lower clamping plate are engaged in a zigzag manner, so as to ensure stable clamping of the sample. The jaw 51 is also provided with an adjustment for adjusting the spacing between the upper and lower jaws to accommodate the testing requirements for samples of different thicknesses.
Referring to fig. 6, the supporting frame 12 is fixed on the testing table 11, the height adjusting mechanism 41 is an electric servo telescopic rod, a fixed end of the electric servo telescopic rod is fixedly connected with the top of the supporting frame 12, and a movable end of the electric servo telescopic rod is connected with the horizontal loading device 4. The height position of the horizontal loading device 4 is adjusted by controlling the extending length of the movable end of the electric servo telescopic rod, so that the height of the clamp 5 connected with the horizontal loading device 4 is kept consistent with that of a sample in the test port 23 (basically on the same horizontal line).
In this embodiment, the testing device is further provided with a temperature control assembly 6, the temperature control assembly 6 comprises a temperature control box 61 covered outside the testing box, and the temperature regulation range in the temperature control box 61 is-20-90 ℃. By adjusting the temperature in the temperature control box 61, simulation tests of creep performance are performed on soil and geosynthetic materials in the test box 2 under different temperature conditions, so that the test conditions are closer to the actual application scene. Preferably, the temperature control box 61 is made of transparent materials, so that the internal test condition of the temperature control box can be observed conveniently.
Furthermore, in order to ensure the accuracy and timeliness of timing, the control system of the testing device of the embodiment further comprises a timing device, the timing device is connected with the control system, the extension of the sample and the time when the sample breaks can be continuously recorded or recorded according to a specified time interval, a specially-assigned person is not required to record any more, and the workload of test operators is reduced. The testing device of the embodiment can also be provided with a power failure protection device and an emergency stop device so as to deal with emergency situations in the testing process and ensure the testing safety.
Example 2
This example provides a testing method based on the device for testing creep performance of geosynthetic material in example 1, which includes the following steps:
s1, adjusting the position of the test port 23 on the pair of adjustable side walls 22 and the height of the horizontal loading device 4 to enable the two to be on the same horizontal line;
s2, laying a first layer of soil to be flush with the horizontal loading device 4;
s3, transversely placing the geosynthetic material sample in the test box 2 filled with soil, and clamping two ends of the geosynthetic material sample by using the clamping jaws 51 of the clamp 5;
s4, laying a second layer of soil to be flush with the top of the fixed side wall 21;
s5, adjusting the temperature control assembly 6 to set a test temperature, starting the vertical loading device 3, and applying a preset pressure to the soil in the test box 2;
and S6, acquiring data at regular intervals until the time required by the test is reached, and ending the test.
Further, before the step S5, the method further includes the following steps: and applying a preloading tension to the geosynthetic material sample by using the horizontal loading device 4 to enable the geosynthetic material sample to generate 1% of tensile strength preloading, recording a tension value through a tension sensor, and recording corresponding displacement through a displacement sensor.
In the operation, through utilizing horizontal loading device 4 to carry out the preloading, make the geosynthetic material produce about 1% tensile strength's preloading to through tension sensor record tension value, through the corresponding displacement of displacement sensor record, thereby start-up test can ensure that each part of test piece contacts well, makes load and deformation relation tend towards stability, improves the degree of accuracy of test result, and ensures that the experiment is gone on smoothly.
In the embodiment, the horizontal loading device 4 is accurate to +/-1%, and the adjustable speed is 0.1-50 mm/min. After applying the horizontal preload, the vertical pressure was gradually increased until the target value was reached after about 1 minute. And continuously collecting the displacement data of the geosynthetic material by using a displacement sensor after the loading process is finished, continuously testing according to the specified testing time, and automatically collecting and recording the relevant data once every 1 minute until the test is finished.
Because the device for testing the creep property of the geosynthetic material adopted by the embodiment has the characteristic that the height of the test port 23 is adjustable, in a specific test, samples of the same batch of geosynthetic material can be placed in soil at different heights for testing the creep property respectively. For example, the creep performance testing data of the geosynthetic material can be placed at positions with scales of 1/4, 1/3, 1/2, 2/3 and 3/4 on the fixed side wall 21 respectively, five groups of data are compared, and the creep performance data under the real soil environment can be calculated according to the simulation test proportion, so that the creep performance change curves of the geosynthetic material under different soil depth conditions can be obtained.
Furthermore, after each test is finished, the horizontal loading device 4 and the clamp 5 are adjusted in the horizontal state, so that the test error is further reduced, and the test precision is improved.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.
Claims (10)
1. A geosynthetic creep performance testing device, comprising: the device comprises a shell (1), a test box (2), a vertical loading device (3), a horizontal loading device (4), a clamp (5), a temperature control assembly (6) and a control system;
the test box (2) is arranged on a test bed (11) at the bottom of the shell (1); the test box (2) comprises a pair of fixed side walls (21) and a pair of adjustable side walls (22), and the adjustable side walls (22) are provided with test ports (23) with adjustable heights;
the vertical loading device (3) is positioned above the test box (2), and the fixed end of the vertical loading device is installed on a transverse frame at the top of the shell (1); the movable end of the vertical loading device (3) is used for applying vertical pressure to soil in the test box (2);
the horizontal loading devices (4) are positioned on two sides of a pair of adjustable side walls (22) of the test box (2) and are arranged on the test bed (11) through a support frame (12); the movable end of the horizontal loading device (4) is connected with a clamp (5), and the clamp (5) is provided with a clamping jaw (51) for clamping a geosynthetic material sample;
a height adjusting mechanism (41) is arranged between the horizontal loading device (4) and the support frame (12); the height adjusting mechanism (41) is used for adjusting the height of the horizontal loading device (4) so that the height of the horizontal loading device (4) is consistent with that of the test port (23);
the control system comprises a power supply, a displacement sensor, a tension sensor, a temperature regulator, a display screen and a control panel.
2. The testing device according to claim 1, characterized in that the adjustable side walls (22) of the test chamber (2) comprise an adjustment frame (221), a top fixing plate (222), a bottom fixing plate (223) and several sliding plates (224);
sliding rails (224) for moving the sliding plate (224) are arranged on two sides of the adjusting frame (221); the test port (23) is formed between adjacent sliding plates (224), between the sliding plates (224) and the top fixing plate (222), or between the sliding plates (224) and the bottom fixing plate (223) by moving the sliding plates (224).
3. A test device as claimed in claim 2, characterized in that the test opening (23) is located 1/4-3/4 of the height of the test chamber (2).
4. The testing device according to claim 1, characterized in that the fixed side wall (21) of the testing box (2) is made of a high-strength transparent material, and a scale (212) is arranged at the edge of the fixed side wall (21) adjacent to the adjustable side wall (22).
5. The testing device according to claim 1, characterized in that the vertical loading means (3) is a hydraulic servo loading means comprising a loading plate (31) at the bottom of the free end, said loading plate (31) being adapted to exert a vertical pressure on the soil inside the test chamber (2).
6. The testing device according to claim 1, wherein the horizontal loading device (4) comprises a horizontal hydraulic servo device, the horizontal loading device (4) is used for providing a preloading tension for the geosynthetic material sample, and the tension rate provided by the horizontal loading device (4) is 0.1-50 mm/min.
7. The testing device according to claim 1, wherein the height adjusting mechanism (41) is an electric servo telescopic rod, the fixed end of the electric servo telescopic rod is installed on the top plate of the supporting frame (12), and the movable end of the electric servo telescopic rod is connected with the horizontal loading device (4).
8. The testing device according to claim 1, wherein the temperature control component (6) comprises a temperature control box (61) covered outside the testing box (2), and the temperature in the temperature control box (61) is adjusted within a range of-20-99 ℃.
9. A method for testing the creep performance of a geosynthetic material based on any of claims 1-8, comprising the steps of:
s1, adjusting the position of the test port (23) on the pair of adjustable side walls (22) and the height of the horizontal loading device (4) to enable the two to be on the same horizontal line;
s2, laying a first layer of soil to be flush with the horizontal loading device (4);
s3, transversely placing the geosynthetic material sample in a test box (2) filled with soil, and clamping two ends of the geosynthetic material sample by using a clamping jaw (51) of a clamp (5);
s4, laying a second layer of soil to be flush with the top of the fixed side wall (21);
s5, adjusting the temperature control assembly (6) to set a test temperature, starting the vertical loading device (3), and applying a preset pressure to the soil in the test box (2);
and S6, acquiring data at regular intervals until the time required by the test is reached, and ending the test.
10. The test method of claim 9, wherein: before the step S5, the method further includes the following steps: and applying a preloading tension to the geosynthetic material sample by using a horizontal loading device (4), so that the geosynthetic material sample generates 1% of tensile strength preload, recording a tension value by using a tension sensor, and recording corresponding displacement by using a displacement sensor.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN116296764A (en) * | 2023-05-16 | 2023-06-23 | 常州萨伟利铸造技术有限公司 | Self-hardening sand creep property measuring equipment |
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