Testing instrument for testing compression modulus of composite foundation in laboratory

Abstract

The utility model discloses a testing instrument for testing the compression modulus of a composite foundation in a laboratory, which belongs to the technical field of instrument measurement and comprises a supporting bottom plate, an earth pressure box is fixedly connected to the upper surface of the supporting bottom plate, and a bearing frame is fixedly connected to the upper surface of the supporting bottom plate and located above the earth pressure box; after the test is finished, the fixation of the U-shaped moving plate can be canceled by simultaneously pulling two pulling discs outwards, then the U-shaped moving plate is shifted downwards to reset the two inclined blocks, and meanwhile, two inserting rods II are pulled out of the interiors of two positioning round holes II, so that the fixation of the moving plate can be completely relieved; and finally, an operator can open the movable plate to conveniently take out the undisturbed soil in the soil pressure box, so that the problem that the undisturbed soil is difficult to take out is effectively solved, the test efficiency is improved, and the possibility that the soil pressure box is damaged due to difficult soil taking is reduced.

Description

Technical Field

[0001] This utility model relates to the field of instrument measurement technology, and in particular to a testing instrument for testing the compression modulus of composite foundations in a laboratory. Background Technology

[0002] In engineering construction, we often encounter special foundations with low bearing capacity, excessive compressibility, or permeability that cannot meet design requirements. These are generally soft foundations. Composite foundations are usually used to treat soft foundations by replacing the soft soil layer or installing materials such as steel bars. They can be divided into two parts: the base and the reinforcement. Composite foundations are widely used to reduce settlement, improve bearing capacity, and save construction costs.

[0003] The prior art (publication number: CN217901408U) discloses a testing instrument for testing the compression modulus of composite foundations in a laboratory. This technology includes a bearing frame, an earth pressure cell, a pressure transmission plate, a dial gauge, a jack, strain gauges, a first permeable stone, a second permeable stone, and a composite foundation. The earth pressure cell includes a bottom and side walls. The bottom of the earth pressure cell is provided with the first permeable stone, the composite foundation is provided above the first permeable stone, the second permeable stone is provided above the composite foundation, and a pressure transmission plate is provided above the second permeable stone. The bearing frame is provided around the earth pressure cell. The bearing frame has a door-shaped structure. The door-shaped structure includes a transverse connecting part and longitudinal support parts connected to both ends of the transverse connecting part. A jack and a dial gauge are connected between the transverse connecting part and the pressure transmission plate. Multiple strain gauges are provided on the composite foundation near the side wall of the earth pressure cell. This application allows for multiple tests in the laboratory without the need for on-site undisturbed soil testing, greatly facilitating the testing process.

[0004] In the aforementioned technology, when conducting undisturbed soil tests on the construction site in the laboratory, the undisturbed soil inside the earth pressure cell is difficult to remove after the test is completed. This requires operators to spend a lot of time and effort to handle, which seriously slows down the entire test progress and affects the project schedule. Utility Model Content

[0005] Purpose of the utility model: The purpose of this utility model is to provide a solution to the problem that the original soil inside the earth pressure cell is difficult to remove after the original soil test is completed in the laboratory at the construction site.

[0006] Technical solution: A testing instrument for testing the compression modulus of composite foundations in a laboratory, comprising a supporting base plate, an earth pressure cell fixedly connected to the upper surface of the supporting base plate, a bearing frame fixedly connected to the upper surface of the supporting base plate and above the earth pressure cell, a jack fixedly connected to the lower surface of the bearing frame, a mounting plate fixedly connected to the lower surface of the jack, a pressure transmission plate provided on the lower surface of the mounting plate, the mounting plate and the pressure transmission plate being detachably connected by bolts, a dial indicator provided on the lower surface of the bearing frame and to the right of the jack, and multiple strain gauges provided on the inner wall of the earth pressure cell;

[0007] The front surface of the earth pressure box is rotatably connected to a movable plate via a hinge. A U-shaped movable plate is provided in front of the movable plate. Vertical plates are fixedly connected to the left and right sides of the earth pressure box. Sliding vertical grooves are provided on the opposite sides of the two vertical plates. Movable blocks are slidably connected to the upper part of the interior of the two sliding vertical grooves. The opposite sides of the two movable blocks are fixedly connected to the U-shaped movable plate. Multiple positioning holes are provided on the opposite sides of the interior of the two sliding vertical grooves. Sliding plates are slidably connected to the interior of the two movable blocks. Insertion rods are fixedly connected to the opposite sides of the two sliding plates. The opposite ends of the two insertion rods extend into the interior of the two positioning holes above.

[0008] Furthermore, multiple support legs are fixedly connected to the lower surface of the support base plate.

[0009] Furthermore, permeable stones are fixedly connected to the lower inner surface of the earth pressure box and the lower surface of the pressure transmission plate.

[0010] Furthermore, a pull rod is fixedly connected to the center of the opposite sides of the two sliding plates, and the opposite ends of the two pull rods extend to the left and right sides of the U-shaped moving plate, and a pull disc is fixedly connected to each of them. Two springs are fixedly connected between the opposite sides of the two sliding plates and the interior of the two moving blocks, respectively.

[0011] Furthermore, the movable plate has symmetrically integrally formed extrusion chambers inside, and piston plates are slidably connected inside each of the two extrusion chambers. An inclined block is fixedly connected to the front surface of each of the two piston plates, and the front ends of each inclined block contact the rear surface of the U-shaped movable plate. Two springs are fixedly connected between the rear surfaces of the two piston plates and the two extrusion chambers, respectively. Sliding chambers are integrally formed inside the movable plate and on opposite sides of the two extrusion chambers. Piston plates are slidably connected inside the two sliding chambers, and plug-in rods are fixedly connected to opposite sides of the two piston plates. Positioning holes are provided on the left and right sides of the inner wall of the earth pressure box. The opposite ends of the two plug-in rods extend into the interiors of the two positioning holes, respectively. Air delivery grooves are provided between the interiors of the two sliding chambers and the two extrusion chambers, respectively.

[0012] Furthermore, a sealing gasket is fixedly connected between the outer wall of the movable plate and the inner wall of the earth pressure box.

[0013] Furthermore, a handle is fixedly connected to the front surface of the movable plate and above the U-shaped movable plate, and the lower surface of the handle is in contact with the upper surface of the U-shaped movable plate.

[0014] Beneficial effects:

[0015] After the test is completed, the fixation of the U-shaped moving plate can be released by simultaneously pulling the two pulling discs outward. Then, the two inclined blocks can be reset by pushing the U-shaped moving plate downward. At the same time, the two plug rods can be pulled out of the two positioning holes. At this point, the fixation of the moving plate can be completely released. Finally, the operator can open the moving plate to easily remove the undisturbed soil inside the earth pressure cell. This effectively solves the problem of the difficulty in removing the undisturbed soil, improves the test efficiency, and reduces the possibility of damage to the earth pressure cell due to the difficulty in removing soil. Attached Figure Description

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

[0017] Figure 2 This is a partial top view of the cross-section of the vertical plate and the movable block of this utility model;

[0018] Figure 3 This is a partial top view of the cross-section of the earth pressure box and the movable plate of this utility model;

[0019] Figure 4 This is a partial internal structural diagram of the earth pressure box of this utility model;

[0020] Figure 5 This is the utility model Figure 1A magnified structural diagram of point A in the middle.

[0021] In the diagram: 1. Support base plate; 2. Earth pressure box; 3. Bearing frame; 4. Jack; 5. Mounting plate; 6. Pressure transmission plate; 7. Dial gauge; 8. Movable plate; 9. U-shaped moving plate; 10. Vertical plate; 11. Sliding vertical groove; 12. Moving block; 13. Positioning hole one; 14. Sliding plate; 15. Connecting rod one; 16. Support leg; 17. Permeable stone; 18. Strain gauge; 19. Tie rod; 20. Pulling disc; 21. Spring one; 22. Extrusion chamber; 23. Piston plate one; 24. Inclined block; 25. Spring two; 26. Sliding chamber; 27. Piston plate two; 28. Connecting rod two; 29. ​​Positioning hole two; 30. Air supply groove; 31. Sealing gasket; 32. Handle. Detailed Implementation

[0022] To make the technical solution of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] Example 1

[0024] like Figure 1 As shown, multiple support legs 16 are fixedly connected to the lower surface of the support base plate 1;

[0025] During the composite foundation compression modulus test, multiple support legs 16 support the weight of the entire instrument and sample, thus ensuring the stability of the instrument during the test.

[0026] like Figure 1 and Figure 4 As shown, a testing instrument for testing the compression modulus of composite foundations in a laboratory is provided, including a supporting base plate 1, an earth pressure cell 2 fixedly connected to the upper surface of the supporting base plate 1, a bearing frame 3 fixedly connected to the upper surface of the supporting base plate 1 and above the earth pressure cell 2, a jack 4 fixedly connected to the lower surface of the bearing frame 3, an mounting plate 5 fixedly connected to the lower surface of the jack 4, a pressure transmission plate 6 provided on the lower surface of the mounting plate 5, and the mounting plate 5 and the pressure transmission plate 6 are connected by bolts for disassembly and detachment. A dial gauge 7 is provided on the lower surface of the bearing frame 3 and to the right of the jack 4, and multiple strain gauges 18 are provided on the inner wall of the earth pressure cell 2.

[0027] During use, the composite foundation sample is stored inside the earth pressure cell 2. Then, the jack 4 is activated, causing it to slowly extend. The mounting plate 5 drives the pressure transmission plate 6 downward, applying vertical pressure to the composite foundation sample inside the earth pressure cell 2. As the jack 4 loads, multiple strain gauges 18 inside the earth pressure cell 2 start working, measuring the pressure changes in the earth pressure cell 2 in real time and converting the pressure signal into an electrical signal, which is then transmitted to the data acquisition system. Simultaneously, the dial gauge 7 starts measuring the displacement changes of the pressure transmission plate 6, accurate to the micrometer level. By recording the vertical displacement values ​​of the pressure transmission plate 6 under different loads, the pressure distribution inside the composite foundation can be understood. When the predetermined maximum load is reached or the predetermined loading steps of the test are completed, the jack 4 begins to slowly unload. During the unloading process, the pressure and displacement data continue to be recorded by the strain gauges 18 and the dial gauge 7, and the rebound of the composite foundation sample during the unloading process is observed. After unloading is completed, the pressure and displacement data collected throughout the test are compiled. Based on these data, the compression modulus of the composite foundation can be calculated.

[0028] like Figure 1 and Figure 4 As shown, permeable stones 17 are fixedly connected to the lower inner surface of the earth pressure box 2 and the lower surface of the pressure transmission plate 6.

[0029] In the experiment, when the composite foundation sample is subjected to pressure applied by the jack 4, the water in the sample will migrate under the pressure. The permeable stone 17 at the bottom of the earth pressure cell 2 allows the water in the earth pressure cell 2 to flow with the water in the sample, ensuring the water pressure balance inside and outside the earth pressure cell 2. At the same time, the permeable stone 17 below the pressure plate 6 helps to drain excess water from the sample, making the contact between the pressure plate 6 and the composite foundation sample more in line with the actual working conditions, avoiding uneven pressure transmission due to water accumulation, and thus ensuring the reliability of the test results.

[0030] like Figure 2 and Figure 5 As shown, the front surface of the earth pressure box 2 is rotatably connected to a movable plate 8 via a hinge. A U-shaped movable plate 9 is provided in front of the movable plate 8. Vertical plates 10 are fixedly connected to the left and right sides of the earth pressure box 2. Sliding vertical grooves 11 are provided on the opposite sides of the two vertical plates 10. Movable blocks 12 are slidably connected to the upper part of the interior of the two sliding vertical grooves 11. The opposite sides of the two movable blocks 12 are fixedly connected to the U-shaped movable plate 9. Multiple positioning round holes 13 are provided on the opposite sides of the interior of the two sliding vertical grooves 11. Sliding plates 14 are slidably connected to the interior of the two movable blocks 12. Insertion rods 15 are fixedly connected to the opposite sides of the two sliding plates 14. The opposite ends of the two insertion rods 15 extend into the interior of the two positioning round holes 13 above.

[0031] After both plug rods 15 are inserted into the corresponding positioning holes 13, the U-shaped moving plate 9 initially locks the movable plate 8. At this time, the position of the movable plate 8 is fixed, and the front of the earth pressure cell 2 is in a relatively closed state, which provides stable conditions for subsequent test operations. At the same time, it can prevent the movable plate 8 from opening accidentally to a certain extent, and ensure the stability of the internal environment of the earth pressure cell 2 during the test.

[0032] like Figure 2 As shown, a pull rod 19 is fixedly connected to the center of the opposite sides of the two sliding plates 14. The opposite ends of the two pull rods 19 extend to the left and right sides of the U-shaped moving plate 9, and a pull disc 20 is fixedly connected to each of them. Two springs 21 are fixedly connected between the opposite sides of the two sliding plates 14 and the interior of the two moving blocks 12, respectively.

[0033] By having the operator simultaneously pull the two pull discs 20 outwards, the two pull rods 19 can be moved, and the two plug rods 15 can be retracted into the two moving blocks 12 through the two pull rods 19. At this time, the fixing of the U-shaped moving plate 9 can be released, and by pulling the U-shaped moving plate 9 downwards, the two sliding vertical grooves 11 can be slid to the bottom of the movable plate 8.

[0034] like Figure 3 As shown, the movable plate 8 has symmetrically integrally formed extrusion chambers 22. Piston plates 23 are slidably connected inside the two extrusion chambers 22. Inclined blocks 24 are fixedly connected to the front surfaces of the two piston plates 23. The front ends of the two inclined blocks 24 are in contact with the rear surfaces of the two U-shaped movable plates 9. Two springs 25 are fixedly connected between the rear surfaces of the two piston plates 23 and the two extrusion chambers 22 respectively. Sliding chambers 26 are integrally formed inside the movable plate 8 and on opposite sides of the two extrusion chambers 22. Piston plates 27 are slidably connected inside the two sliding chambers 26. Insertion rods 28 are fixedly connected to opposite sides of the two piston plates 27. Positioning holes 29 are opened on the left and right sides of the inner wall of the earth pressure box 2. The opposite ends of the two insertion rods 28 extend into the interior of the two positioning holes 29 respectively. Air delivery grooves 30 are opened between the interior of the two sliding chambers 26 and the two extrusion chambers 22 respectively.

[0035] When the U-shaped moving plate 9 is pressing the two inclined blocks 24 from above, the movable plate 8 can be further fixed by the two connecting rods 28 and the two positioning holes 29, preventing the movable plate 8 from opening or closing due to pressure during the test. When the two movable plates 8 are pulled simultaneously to release the fixation of the U-shaped moving plate 9, and the U-shaped moving plate 9 is slid to the bottom of the movable plate 8, the two inclined blocks 24 extend to the front of the movable plate 8 by the rebound of the spring 25. At the same time, the piston plate 23 slides forward inside the compression chamber 22, and the airflow inside the two sliding chambers 26 is delivered to the inside of the two compression chambers 22 through the two air channels 30. Thus, the two connecting rods 28 are pulled out of the inside of the two positioning holes 29 by the two piston plates 27. At this time, the fixation of the movable plate 8 can be completely released, and the operator can take out the composite foundation sample inside the earth pressure box 2. At the same time, the inside of the earth pressure box 2 can be rinsed by spray gun or other objects, which increases the efficiency of the test.

[0036] like Figure 3 As shown, a sealing gasket 31 is fixedly connected between the outer wall of the movable plate 8 and the inner wall of the earth pressure box 2.

[0037] There may be minor processing errors or assembly gaps between the movable plate 8 and the earth pressure cell 2. The sealing gasket 31 can effectively fill these gaps to prevent the composite foundation sample inside the earth pressure cell 2 from leaking to the outside due to pressure, thereby reducing the experimental data.

[0038] like Figure 1 As shown, a handle 32 is fixedly connected to the front surface of the movable plate 8 and above the U-shaped movable plate 9, and the lower surface of the handle 32 is in contact with the upper surface of the U-shaped movable plate 9.

[0039] The handle 32 is designed to facilitate gripping and applying force by the operator, while also limiting the maximum height of the U-shaped moving plate 9, thus improving the accuracy of the device.

[0040] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A testing instrument for testing the compression modulus of composite foundations in a laboratory, comprising a supporting base plate (1), characterized in that: The upper surface of the supporting base plate (1) is fixedly connected to an earth pressure box (2). The upper surface of the supporting base plate (1) and above the earth pressure box (2) is fixedly connected to a bearing frame (3). The lower surface of the bearing frame (3) is fixedly connected to a jack (4). The lower surface of the jack (4) is fixedly connected to an mounting plate (5). The lower surface of the mounting plate (5) is provided with a pressure transmission plate (6). The mounting plate (5) and the pressure transmission plate (6) are connected by bolts. The lower surface of the bearing frame (3) and to the right of the jack (4) is provided with a dial indicator (7). The inner wall of the earth pressure box (2) is provided with multiple strain gauges (18). The front surface of the earth pressure box (2) is rotatably connected to a movable plate (8) via a hinge. A U-shaped movable plate (9) is provided in front of the movable plate (8). Vertical plates (10) are fixedly connected to the left and right sides of the earth pressure box (2). Sliding vertical grooves (11) are provided on opposite sides of the two vertical plates (10). Moving blocks (12) are slidably connected to the upper part of the two sliding vertical grooves (11). The opposite sides of the two moving blocks (12) are fixedly connected to the U-shaped movable plate (9). Multiple positioning round holes (13) are provided on opposite sides of the two sliding vertical grooves (11). Sliding plates (14) are slidably connected to the inside of the two moving blocks (12). Insertion rods (15) are fixedly connected to the opposite sides of the two sliding plates (14). The opposite ends of the two insertion rods (15) extend into the inside of the two positioning round holes (13) above.

2. The testing instrument for testing the compression modulus of composite foundations in a laboratory according to claim 1, characterized in that: Multiple support legs (16) are fixedly connected to the lower surface of the support base plate (1).

3. The testing instrument for testing the compression modulus of composite foundations in a laboratory according to claim 1, characterized in that: The lower inner surface of the earth pressure box (2) and the lower surface of the pressure transmission plate (6) are both fixedly connected with permeable stones (17).

4. The testing instrument for testing the compression modulus of composite foundations in a laboratory according to claim 1, characterized in that: Pull rods (19) are fixedly connected to the center of the opposite sides of the two sliding plates (14). The opposite ends of the two pull rods (19) extend to the left and right sides of the U-shaped moving plate (9) and are fixedly connected to a pull disc (20). Two springs (21) are fixedly connected between the opposite sides of the two sliding plates (14) and the interior of the two moving blocks (12).

5. The testing instrument for testing the compression modulus of composite foundations in a laboratory according to claim 1, characterized in that: The movable plate (8) has symmetrically integrally formed extrusion chambers (22). Piston plates (23) are slidably connected inside each of the two extrusion chambers (22). An inclined block (24) is fixedly connected to the front surface of each of the two piston plates (23). The front ends of the two inclined blocks (24) are in contact with the rear surface of the U-shaped movable plate (9). Two springs (25) are fixedly connected between the rear surfaces of the two piston plates (23) and the two extrusion chambers (22), respectively. The movable plate (8) is located inside and within the two extrusion chambers (22). Both sides of the two sliding chambers (26) are integrally formed with sliding cavities (26). Piston plates (27) are slidably connected inside the two sliding cavities (26). Insertion rods (28) are fixedly connected to the opposite sides of the two piston plates (27). Positioning holes (29) are provided on the left and right sides of the inner wall of the earth pressure box (2). The opposite ends of the two insertion rods (28) extend into the interior of the two positioning holes (29). Air delivery grooves (30) are provided between the interior of the two sliding cavities (26) and the two extrusion cavities (22).

6. The testing instrument for testing the compression modulus of composite foundations in a laboratory according to claim 1, characterized in that: A sealing gasket (31) is fixedly connected between the outer wall of the movable plate (8) and the inner wall of the earth pressure box (2).

7. The testing instrument for testing the compression modulus of composite foundations in a laboratory according to claim 1, characterized in that: A handle (32) is fixedly connected to the front surface of the movable plate (8) and above the U-shaped movable plate (9), and the lower surface of the handle (32) is in contact with the upper surface of the U-shaped movable plate (9).

Images