Pile foundation vertical compression resistance static load test device
By designing a static load test device for vertical compressive strength of pile foundations with load-bearing connecting blocks, telescopic connecting beams, and load-bearing mechanisms, the safety and cost issues of existing devices have been solved, and efficient and safe test data acquisition without the need for precast concrete blocks has been achieved.
Patent Information
- Application Number
- CN202520423981.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-12
- Publication Date
- 2026-02-10
- Estimated Expiration
- 2035-03-12
AI Technical Summary
Existing vertical static load testing devices for pile foundations have low safety and high testing costs, especially when using precast concrete blocks, which pose safety hazards and high costs.
A static load test device for vertical compressive strength of pile foundation was designed, which includes a load-bearing connecting block, a telescopic connecting beam, a loading box and a bearing mechanism. The force balance is achieved by adjusting the jack and push-pull device between the load-bearing connecting block and the bearing mechanism, and the test pile is protected by rubber pads and hoops to avoid direct contact and crushing.
The elimination of the need to purchase or manufacture precast concrete blocks reduces testing costs, improves the accuracy and safety of test data, ensures that the test pile is always in a state of stress balance, and prevents deformation and crushing.
Smart Images
Figure CN223893434U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of static load testing technology for pile foundations, specifically a static load testing device for vertical compressive strength of pile foundations. Background Technology
[0002] The static load test for pile foundations is a test method used to determine the vertical compressive bearing capacity of a single pile. Its main purpose is to observe the settlement of the pile by applying axial pressure in stages, thereby determining whether the pile's bearing capacity meets design requirements. This test method is not only applicable to bridge engineering but also widely used in the pile foundation testing of various types of buildings. Loading methods for static load tests include the surcharge method, the anchor pile method, and the self-balancing method.
[0003] The surcharge method typically employs a surcharge reaction beam device. A load-bearing platform is constructed using steel beams at the top of the pile, and counterweights are stacked on top. Jacks placed at the pile head gradually lift the load-bearing platform, thereby applying force to the pile body. The counterweights are generally precast concrete blocks. These blocks need to be hoisted onto the load-bearing platform one by one using a crane. During hoisting, the load-bearing platform may tilt due to unbalanced forces, causing the precast concrete blocks to overturn and creating a safety hazard. Furthermore, the purchase and transportation costs of precast concrete blocks are relatively high. Manufacturing precast concrete blocks also requires significant labor and materials, and the large quantity required for production adds considerable time. Utility Model Content
[0004] This invention proposes a static load test device for vertical compressive strength of pile foundations, which solves the problems of low safety and high test cost of current static load test devices for vertical compressive strength of pile foundations.
[0005] To achieve the above objectives, this utility model proposes a static load test device for vertical compressive strength of pile foundations, comprising a load-bearing connecting block, a telescopic connecting beam, a loading box, and a bearing mechanism fixed to the upper end of the test pile.
[0006] The connecting beams are provided in multiple sets, with two beams in each set, and the loading boxes are provided in multiple sets. The multiple sets of connecting beams are evenly arranged around the load-bearing connecting block. One end of the connecting beam is fixed to the side of the load-bearing connecting block, and the loading box is fixed to the other end of the connecting beam.
[0007] The load-bearing connecting block is located above the load-bearing mechanism, and a lifting device is installed between the load-bearing connecting block and the load-bearing mechanism.
[0008] Preferably, the connecting beam includes a main beam and a secondary beam. The main beam is a tubular structure and is fixed to the side of the load-bearing connecting block. One end of the secondary beam slides within the main beam.
[0009] Preferably, the secondary beam includes a bottom support, a vertical part, and a horizontal part. One end of the horizontal part slides within the main beam, the upper end of the vertical part is fixed to the other end of the horizontal part, the bottom support is fixed to the lower end of the vertical part, and the loading box is fixed to the bottom support.
[0010] Preferably, push-pull plates are fixed on the two horizontal parts of the secondary beams in the same group, and multiple reinforcing plates are provided at the connection between the push-pull plates and the horizontal parts;
[0011] A push-pull device is installed between the push-pull plate and the load-bearing connecting block.
[0012] Preferably, the lower surface of the main beam is provided with a connecting column, and the lower end of the connecting column is fixed to the ground by a plurality of fixing rods.
[0013] Preferably, the bearing mechanism includes a bearing plate, an adjusting plate, and a pile top retaining ring;
[0014] The pile top protective ring is fixed to the lower surface of the bearing plate, the adjusting plate slides on the upper surface of the bearing plate, the jack slides on the upper surface of the adjusting plate, and the sliding direction of the jack is perpendicular to the sliding direction of the adjusting plate.
[0015] The bearing plate abuts against the upper end of the test pile, and the pile top protective ring is fitted over the outside of the test pile body.
[0016] Preferably, the lower surface of the bearing plate is provided with a rubber pad, which is disposed inside the pile top protective ring and abuts against the upper end of the test pile.
[0017] Preferably, the peripheral side of the pile top protective ring is provided with multiple connecting plates.
[0018] Preferably, the test pile has a hoop on its circumferential side, the hoop is located below the bearing mechanism, the hoop has a plurality of slots on its circumferential side, the slots correspond to the positions of the connecting plate, and the lower end of the connecting plate is inserted into the slot.
[0019] Preferably, the lower surface of the load-bearing connecting block is provided with a force transmission plate, the force transmission plate is frustoconical, the small end face of the force transmission plate faces downward, and the output end of the lifting device abuts against the small end face of the force transmission plate.
[0020] This utility model has the following beneficial effects:
[0021] 1. When using this test device to conduct static load tests on vertical compressive strength of pile foundations, there is no need to purchase or rent precast concrete blocks, nor is it necessary to manufacture precast concrete blocks, thus saving test costs. If the test device experiences a force imbalance, it can be adjusted by reducing or increasing the weight of the soil or gravel in one of the loading boxes. The push-pull device can also be activated, which pushes the push-pull plate, causing the secondary beam to extend or retract. In this way, the test device can be made to reach a state of force balance by adjusting the length of the connecting beam, thereby improving the accuracy of the test data and being more convenient.
[0022] 2. The adjusting plate can slide on the bearing plate, and the jacking device can slide on the adjusting plate. Moreover, the sliding direction of the jacking device is perpendicular to the sliding direction of the adjusting plate. This makes it easy to adjust the position of the jacking device on the bearing plate. By adjusting the position of the jacking device on the bearing plate, the axis of the jacking device can be further aligned with the axis of the test pile, thereby further improving the accuracy of the test data.
[0023] 3. Since the upper surface of the test pile is uneven, setting up a rubber pad can prevent the upper surface of the test pile from directly contacting the lower surface of the bearing plate, thus preventing deformation of the bearing plate.
[0024] 4. The hoop can protect the test pile and prevent it from being crushed, which would affect the progress of the test;
[0025] 5. Multiple connecting plates can disperse the pressure on the bearing plate and transfer it to the hoop. The hoop can then evenly transfer the dispersed pressure to the test pile, keeping the test pile in a state of stress balance. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the overall structure of the pile foundation vertical compressive static load test device described in this utility model;
[0027] Figure 2 This is a schematic diagram of the connecting beam in the pile foundation vertical compressive static load test device described in this utility model;
[0028] Figure 3 This is a schematic diagram of the bearing mechanism in the pile foundation vertical compressive static load test device of this utility model;
[0029] Figure 4 This is a schematic diagram showing the connection between the bearing mechanism and the load-bearing connecting block in the pile foundation vertical compressive static load test device of this utility model;
[0030] Figure 5 This is a schematic diagram showing the connection between the bearing mechanism and the semi-hoop in the vertical compressive static load test device for pile foundations described in this utility model.
[0031] In the diagram: 1. Test pile; 2. Load-bearing connecting block; 3. Connecting beam; 31. Main beam; 32. Secondary beam; 321. Bottom support; 322. Vertical section; 323. Horizontal section; 324. Diagonal brace; 33. Push-pull plate; 34. Reinforcing plate; 4. Loading box; 5. Push-pull device; 6. Connecting column; 7. Fixing rod; 8. Bearing mechanism; 81. Bearing plate; 82. Adjusting plate; 83. Pile top protective ring; 84. Connecting plate; 85. Rubber pad; 9. Hoop; 91. Slot; 100. Lifting device; 200. Force transmission plate; 300. Displacement sensor. Detailed Implementation
[0032] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments, so that those skilled in the art can implement it based on the description.
[0033] This utility model proposes a static load test device for vertical compressive strength of pile foundations, such as... Figure 1 , Figure 2 and Figure 3 As shown, it includes a load-bearing connecting block 2, a telescopic connecting beam 3, a loading box 4, and a bearing mechanism 8 fixed to the upper end of the test pile 1. The connecting beam 3 is provided in multiple sets, with two beams in each set, and the loading box 4 is provided in multiple sets. The multiple sets of connecting beams 3 are evenly arranged around the load-bearing connecting block 2. One end of the connecting beam 3 is fixed to the side of the load-bearing connecting block 2, and the loading box 4 is fixed to the other end of the connecting beam 3. The load-bearing connecting block 2 is located above the bearing mechanism 8, and a jacking device 100 is installed between the load-bearing connecting block 2 and the bearing mechanism 8.
[0034] like Figure 2 As shown, the connecting beam 3 includes a main beam 31 and a secondary beam 32. The main beam 31 is a tubular structure and is fixed to the side of the load-bearing connecting block 2. One end of the secondary beam 32 slides inside the main beam 31.
[0035] like Figure 2 As shown, the secondary beam 32 includes a bottom support 321, a vertical part 322 and a horizontal part 323. One end of the horizontal part 323 slides inside the main beam 31. The upper end of the vertical part 322 is fixed to the other end of the horizontal part 323. The bottom support 321 is fixed to the lower end of the vertical part 322. The loading box 4 is fixed to the top of the bottom support 321.
[0036] like Figure 2 As shown, a diagonal brace 324 is provided at the connection between the horizontal part 323 and the vertical part 322.
[0037] Setting up diagonal brace 324 can improve the connection stability between horizontal part 323 and vertical part 322.
[0038] like Figure 2 As shown, push-pull plates 33 are fixed on the two horizontal parts 323 of the secondary beam 32 in the same group, and multiple reinforcing plates 34 are provided at the connection between the push-pull plates 33 and the horizontal parts 323.
[0039] like Figure 2 As shown, a push-pull device 5 is installed between the push-pull plate 33 and the load-bearing connecting block 2.
[0040] Both the pusher / puller 5 and the lifter 100 use hydraulic cylinders.
[0041] like Figure 2 As shown, the lower surface of the main beam 31 is provided with a connecting column 6, and the lower end of the connecting column 6 is fixed to the ground by multiple fixing rods 7.
[0042] like Figure 3 As shown, the bearing mechanism 8 includes a bearing plate 81, an adjusting plate 82, and a pile top protective ring 83. The pile top protective ring 83 is fixed to the lower surface of the bearing plate 81, the adjusting plate 82 slides on the upper surface of the bearing plate 81, the jacking device 100 slides on the upper surface of the adjusting plate 82, and the sliding direction of the jacking device 100 is perpendicular to the sliding direction of the adjusting plate 82. The bearing plate 81 abuts against the upper end of the test pile 1, and the pile top protective ring 83 is sleeved on the outside of the pile body of the test pile 1.
[0043] The adjusting plate 82 can slide on the bearing plate 81, and the jacking device 100 can slide on the adjusting plate 82. Moreover, the sliding direction of the jacking device 100 is perpendicular to the sliding direction of the adjusting plate 82. This allows for convenient adjustment of the position of the jacking device 100 on the bearing plate 81. By adjusting the position of the jacking device 100 on the bearing plate 81, the axis of the jacking device 100 can be further aligned with the axis of the test pile 1, thereby further improving the accuracy of the test data.
[0044] like Figure 4 and Figure 5 As shown, the lower surface of the bearing plate 81 is provided with multiple displacement sensors 300, which are evenly arranged around the pile top protective ring 83.
[0045] The displacement sensor 300 is electrically connected to the static load tester.
[0046] The displacement sensor 300 plays a role in the test by monitoring the minute displacement of the pile foundation and transmitting the corresponding signal changes to the static load tester. After the static load tester detects the relevant signal changes, it processes the signals to display the force and displacement of the pile foundation and ultimately detects the bearing capacity of the pile foundation.
[0047] like Figure 5 As shown, a rubber pad 85 is provided on the lower surface of the bearing plate 81. The rubber pad 85 is set inside the pile top protective ring 83 and abuts against the upper end of the test pile 1.
[0048] Since the upper surface of the test pile 1 is uneven, the rubber pad 85 can prevent the upper surface of the test pile 1 from directly contacting the lower surface of the bearing plate 81, thus preventing the bearing plate 81 from deforming.
[0049] like Figure 3 and Figure 5 As shown, the periphery of the pile top protective ring 83 is provided with multiple connecting plates 84.
[0050] like Figure 3 , Figure 4 and Figure 5 As shown, the test pile 1 has a hoop 9 on its circumferential side. The hoop 9 is located below the bearing mechanism 8. The hoop 9 has multiple slots 91 on its circumferential side. The slots 91 correspond to the positions of the connecting plate 84. The lower end of the connecting plate 84 is inserted into the slot 91.
[0051] The hoop 9 can protect the test pile 1 and prevent it from being crushed, thus affecting the test.
[0052] Multiple connecting plates 84 can disperse the pressure on the bearing plate 81 and transfer it to the hoop 9. The hoop 9 can evenly transfer the dispersed pressure to the test pile 1, so that the test pile 1 is always in a state of force balance.
[0053] like Figure 4 As shown, the lower surface of the load-bearing connecting block 2 is provided with a force transmission plate 200. The force transmission plate 200 is frustoconical, with the small end face of the force transmission plate 200 facing downwards. The output end of the lifting device 100 abuts against the small end face of the force transmission plate 200.
[0054] The force transmission plate 200 is designed in the shape of a frustum, which can disperse the force of the lifting device 100 and transmit it evenly to the load-bearing connecting block 2, thereby further maintaining the force balance of the entire test device.
[0055] Using this invention, the hoop 9 is first fixed to the periphery of the pile body. Then, the bearing mechanism 8 is installed on the upper end of the test pile 1, and the lower end of the connecting plate 84 is inserted into the slot 91. Subsequently, the load-bearing connecting block 2, the connecting beam 3, and the loading box 4 are installed, and the force transmission plate 200 on the lower surface of the load-bearing connecting block 2 is aligned with the test pile 1. The connecting column 6 is fixed to the ground by multiple fixing rods 7. Then, soil or gravel is poured into multiple loading boxes 4. This eliminates the need to purchase or rent precast concrete blocks, and also eliminates the need to manufacture precast concrete blocks, saving on testing costs. If the test device experiences a force imbalance, the weight of the soil or gravel in one of the loading boxes 4 can be reduced or increased. To make adjustments, the push-pull device 5 can be activated, which pushes the push-pull plate 33. The push-pull plate 33 then extends or retracts the secondary beam 32. This allows the test device to reach a state of force balance by adjusting the length of the connecting beam 3, thereby improving the accuracy of the test data. This method is also quite convenient. Finally, the lifting device 100 is installed on the adjusting plate 82. The adjusting plate 82 and the lifting device 100 are then moved to adjust the position of the lifting device 100 on the bearing plate 81, aligning the lifting device 100 with the force transmission plate 200. The lifting device 100 is then activated, causing its output end to press against the force transmission plate 200. Multi-stage loading is then performed according to the test requirements, and the test data is subsequently recorded.
[0056] Although the embodiments of this utility model have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for this utility model. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, this utility model is not limited to the specific details and the illustrations shown and described herein.
Claims
1. A static load test device for vertical compressive strength of pile foundations, characterized in that, It includes a load-bearing connecting block (2), a telescopic connecting beam (3), a loading box (4), and a bearing mechanism (8) fixed to the upper end of the test pile (1); The connecting beam (3) is provided in multiple sets, with two in each set, and the loading box (4) is provided in multiple sets. The multiple sets of connecting beams (3) are evenly arranged around the load-bearing connecting block (2). One end of the connecting beam (3) is fixed to the side of the load-bearing connecting block (2), and the loading box (4) is fixed to the other end of the connecting beam (3). The load-bearing connecting block (2) is located above the bearing mechanism (8), and a lifting device (100) is installed between the load-bearing connecting block (2) and the bearing mechanism (8).
2. The pile foundation vertical compressive static load test device according to claim 1, characterized in that, The connecting beam (3) includes a main beam (31) and a secondary beam (32). The main beam (31) is a tubular structure. The main beam (31) is fixed to the side of the load-bearing connecting block (2). One end of the secondary beam (32) slides inside the main beam (31).
3. The pile foundation vertical compressive static load test device according to claim 2, characterized in that, The secondary beam (32) includes a bottom support (321), a vertical part (322) and a horizontal part (323). One end of the horizontal part (323) slides inside the main beam (31). The upper end of the vertical part (322) is fixed to the other end of the horizontal part (323). The bottom support (321) is fixed to the lower end of the vertical part (322). The loading box (4) is fixed on the bottom support (321).
4. The pile foundation vertical compressive static load test device according to claim 3, characterized in that, Push-pull plates (33) are fixed on the two horizontal parts (323) of the secondary beam (32) in the same group, and multiple reinforcing plates (34) are provided at the connection between the push-pull plates (33) and the horizontal parts (323); A push-pull device (5) is installed between the push-pull plate (33) and the load-bearing connecting block (2).
5. The pile foundation vertical compressive static load test device according to claim 2, characterized in that, The lower surface of the main beam (31) is provided with a connecting column (6), and the lower end of the connecting column (6) is fixed to the ground by multiple fixing rods (7).
6. The pile foundation vertical compressive static load test device according to claim 1, characterized in that, The bearing mechanism (8) includes a bearing plate (81), an adjusting plate (82), and a pile top retaining ring (83); The pile top protective ring (83) is fixed to the lower surface of the bearing plate (81), the adjusting plate (82) slides on the upper surface of the bearing plate (81), the jacking device (100) slides on the upper surface of the adjusting plate (82), and the sliding direction of the jacking device (100) is perpendicular to the sliding direction of the adjusting plate (82). The bearing plate (81) abuts against the upper end of the test pile (1), and the pile top protective ring (83) is fitted over the pile body of the test pile (1).
7. The pile foundation vertical compressive static load test device according to claim 6, characterized in that, The lower surface of the bearing plate (81) is provided with a rubber pad (85), which is located inside the pile top protective ring (83) and abuts against the upper end of the test pile (1).
8. The pile foundation vertical compressive static load test device according to claim 6, characterized in that, The pile top protective ring (83) is provided with multiple connecting plates (84) on its peripheral side.
9. The pile foundation vertical compressive static load test device according to claim 8, characterized in that, The test pile (1) has a hoop (9) on its circumferential side. The hoop (9) is located below the bearing mechanism (8). The hoop (9) has multiple slots (91) on its circumferential side. The slots (91) correspond to the positions of the connecting plate (84). The lower end of the connecting plate (84) is inserted into the slots (91).
10. The pile foundation vertical compressive static load test device according to claim 1, characterized in that, The lower surface of the load-bearing connecting block (2) is provided with a force transmission plate (200), which is frustum-shaped. The small end face of the force transmission plate (200) faces downward, and the output end of the lifting device (100) abuts against the small end face of the force transmission plate (200).