Counter-force device for static load test of cast-in-place pile
By designing reaction devices for pile structures, beam structures, and centering limiting components, the problem of centering control in static load tests of cast-in-place piles was solved, achieving precise centering of the reaction device and system stability, thus improving the accuracy and efficiency of the test.
Patent Information
- Application Number
- CN202423182292.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-23
- Publication Date
- 2026-01-27
- Estimated Expiration
- 2034-12-23
AI Technical Summary
The existing reaction devices for static load tests of cast-in-place piles have difficulties in centering control, leading to inaccurate test data and system instability.
A reaction device comprising a pile structure, a beam structure, a hydraulic jack, and a centering and limiting component was designed. Precise centering is achieved through angle steel, adjusting bolts, and limiting locking rods. Combined with a standard sand layer, stress concentration and eccentric force are reduced, thereby improving system stability.
It achieves precise alignment of the reaction device, improves the stability and accuracy of the test, and can simultaneously detect the compressive and tensile properties of the cast-in-place pile, thereby improving the test efficiency and accuracy.
Smart Images
Figure CN223838140U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of reaction device technology, and in particular to a reaction device for static load testing of cast-in-place piles. Background Technology
[0002] In construction engineering, static testing of foundation piles requires addressing the source of reaction forces. Currently, there are three main types of reaction devices commonly used in static load tests of filled piles both domestically and internationally: surcharge reaction devices, anchor pile reaction devices, and ground anchor reaction devices.
[0003] During the installation of the surcharge reaction device, it is necessary to ensure that the reaction point is located at the center of the pile head. There is a problem with centering. The uniformity of the counterweight loading process needs to be controlled, otherwise it may lead to eccentric instability or distortion of test data.
[0004] Traditional anchor pile reaction devices are difficult to align with the load during installation, and are prone to hydraulic over-pressure at the beginning of the test, which can affect the settlement of the test pile and potentially the accuracy of the test results.
[0005] Ground anchor reaction devices are only suitable for small-tonnage tests, and they also have the problems of centering and hydraulic pressure overshoot.
[0006] Therefore, the applicant has researched and developed a reaction device for static load testing of cast-in-place piles. Utility Model Content
[0007] This invention proposes a reaction device for static load testing of cast-in-place piles to solve the problem of difficulty in controlling the centering of existing reaction devices.
[0008] This utility model achieves the above objectives through the following technical solutions:
[0009] This utility model provides a reaction device for static load testing of cast-in-place piles, comprising:
[0010] A pile structure, comprising compression piles and reaction piles;
[0011] The beam structure includes a main beam and a secondary beam. Two secondary beams are respectively erected at both ends of the top surface of the main beam. The reaction piles are respectively arranged below the two ends of the secondary beams. The reaction piles are anchored to the ends of the secondary beams through an anchoring structure.
[0012] A hydraulic jack, wherein the jack rod is mounted on the bottom surface of the main beam, and the anti-compression pile is mounted on the bottom of the hydraulic jack;
[0013] The centering limiting assembly includes angle steel, adjusting bolts, a first limiting locking rod, a second limiting locking rod, and limiting fixing bolts. Angle steel is provided at each of the four intersection points of the secondary beam and the main beam. The lower part of one side plate of each of the four angle steels is connected to the main beam via limiting fixing bolts. The upper part of the other side plate of each of the four angle steels is connected to the secondary beam via adjusting bolts. The lower part of one side plate of the front and rear angle steels is locked and connected via limiting locking rods passing through the main beam. The upper part of one side plate of the front and rear angle steels is locked and connected via limiting locking rods passing through the secondary beam.
[0014] Furthermore, a pad is provided between the top surface of the compression pile and the bottom surface of the hydraulic jack, and a first coupling sand layer is provided between the pad and the bottom surface of the hydraulic jack. The first coupling sand layer is a standard sand layer.
[0015] Furthermore, a second coupling sand layer is provided between the two ends of the top surface of the main beam and the secondary beam, and the second coupling sand layer is a standard sand layer.
[0016] The coupling contact between the first coupling sand layer and the second coupling sand layer can effectively reduce stress concentration or eccentric force during the test, while avoiding pressure overshoot, reducing the impact of system deviation on the test results, and improving the stability and reliability of the system.
[0017] Specifically, one side plate of the angle steel is connected to the secondary beam by a bolt structure.
[0018] Furthermore, a main beam reinforcing plate is provided between the top rod of the hydraulic jack and the bottom surface of the main beam.
[0019] Furthermore, both the compression pile and the reaction pile are equipped with a large-range dial gauge.
[0020] Furthermore, concrete supports are respectively placed at both ends of the bottom surface of the main beam.
[0021] Specifically, the anchoring structure includes an anchor plate, an anchor cable, and an anchor bolt. The anchor plate is disposed on the top surface of the end of the secondary beam. The upper end of the anchor cable passes through the end of the secondary beam and is connected to the anchor plate through the anchor bolt. The lower end of the anchor cable is connected to the reaction pile.
[0022] Specifically, the anchor cable includes a tensile anchor bolt, a butt bolt, and an anchor bar connected in sequence from top to bottom. The tensile anchor bolt is connected to the anchor plate through the anchor bolt, and the anchor bar is connected to the reaction pile.
[0023] Furthermore, the hydraulic jack is connected to an oil pressure gauge.
[0024] The beneficial effects of this utility model are as follows:
[0025] This utility model discloses a reaction device for static load testing of cast-in-place piles. The device has a simple structure and is easy to use. It can precisely control the installation alignment by adjusting the bolts, thereby solving the load alignment problem, improving the stability and reliability of the system, and realizing the simultaneous testing of the compressive and tensile properties of the cast-in-place piles, greatly improving the efficiency and accuracy of the test. Attached Figure Description
[0026] Figure 1 This is a top view of a reaction device for a static load test of a cast-in-place pile according to an embodiment of this utility model;
[0027] Figure 2 This is an elevation view of a reaction device for a static load test of a cast-in-place pile according to an embodiment of this utility model;
[0028] Figure 3 This is a side view of a reaction device for a static load test of a cast-in-place pile according to an embodiment of this utility model;
[0029] Figure 4 This is a schematic diagram of the connection structure between the secondary beam and the reaction pile in an embodiment of this utility model;
[0030] Figure 5 This is a schematic diagram of the coupling contact between the compression pile and the pad in an embodiment of this utility model;
[0031] Figure 6 This is a schematic diagram of the coupling contact between the main beam and the secondary beam in an embodiment of this utility model;
[0032] Figure 7 This is a schematic diagram of the centering and limiting component installation in an embodiment of this utility model (view along the secondary beam direction).
[0033] Figure 8 This is a schematic diagram of the installation of the centering and limiting component in an embodiment of this utility model (view along the main beam direction).
[0034] Figure 9 This is a perspective view of a reaction device for a static load test of a cast-in-place pile according to an embodiment of this utility model.
[0035] The numbers in the attached diagram are as follows: 1. Compression pile; 2. Reaction pile; 3. Main beam; 4. Secondary beam; 5. Hydraulic jack; 6. Pad plate; 7. Main beam reinforcing plate; 8. Square anchor plate; 9. Large range dial indicator; 10. Concrete support; 11. Foundation ground; 12. Anchor bolt; 13. Tensile anchor bolt; 14. Butt bolt; 15. Anchor bar; 16. Limiting angle steel; 17. Adjusting bolt; 18. First coupling sand layer; 19. Second coupling sand layer; 20. Limiting fixing bolt; 21. Limiting locking tie rod. Detailed Implementation
[0036] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0037] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0038] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0039] In the description of this utility model, it should be understood that the terms "upper", "lower", "inner", "outer", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the utility model product is usually placed in during use, or the orientation or positional relationship that is commonly understood by those skilled in the art. They are only used to facilitate the description of this utility model and to simplify the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0040] Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.
[0041] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, terms such as "set" and "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0042] The specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings.
[0043] like Figure 1-4 and Figure 9As shown, a reaction device for a static load test of a cast-in-place pile includes:
[0044] A pile structure, comprising compression piles 1 and reaction piles 2;
[0045] The beam structure includes a main beam 3 and a secondary beam 4. The two secondary beams 4 are respectively erected at both ends of the top surface of the main beam 3. The reaction piles 2 are respectively arranged below the two ends of the secondary beams 4. The reaction piles 2 are anchored to the ends of the secondary beams 4 through an anchoring structure.
[0046] Hydraulic jack 5, the jack rod of the hydraulic jack 5 is mounted on the bottom surface of the main beam 3, and the anti-compression pile 1 is mounted on the bottom of the hydraulic jack 5;
[0047] like Figure 7 , 8 As shown, the centering limiting assembly includes angle steel 16, adjusting bolts 17, a first limiting locking rod 21, a second limiting locking rod 21, and limiting fixing bolts 20. The angle steel 16 is provided at the four intersection points of the secondary beam 4 and the main beam 3. The lower part of one side plate of the four angle steel 16 is connected to the main beam 3 by limiting fixing bolts 20, and the upper part of the other side plate of the four angle steel 16 is connected to the secondary beam 4 by adjusting bolts 17. The lower part of one side plate of the front and rear angle steel 16 is locked and connected by limiting locking rods 21 passing through the main beam 3, and the upper part of one side plate of the front and rear angle steel 16 is locked and connected by limiting locking rods 21 passing through the secondary beam 4. During installation, the angle steel 16 is first fixed on the main beam 3, and then the secondary beam 4 is placed at the intersection of the four limiting angle steels 16 on the main beam 3. Then, the installation position of the secondary beam 4 is precisely adjusted using the adjusting bolt 17. After adjustment, it is locked by the limiting locking rod 21.
[0048] like Figure 5 As shown, in some embodiments, a pad 6 is provided between the top surface of the compression pile 1 and the bottom surface of the hydraulic jack 5, and a first coupling sand layer 18 is provided between the pad 6 and the bottom surface of the hydraulic jack 5. The first coupling sand layer 18 is a standard sand layer.
[0049] like Figure 6 As shown, in some embodiments, a second coupling sand layer 19 is provided between the two ends of the top surface of the main beam 3 and the secondary beam 4, and the second coupling sand layer 19 is a standard sand layer.
[0050] Preferably, the pad 6 is a disc pad. When installing the disc pad, a layer of standard sand with a thickness of about 3-5 mm is laid on the top of the compression pile 1 to ensure coupling contact between the pad 6 and the pile head of the compression pile 1. When installing the secondary beam 4, a layer of standard sand with a thickness of about 3-5 mm is laid on the contact surface where the main beam 3 and the secondary beam 4 intersect to ensure coupling contact between the main beam 3 and the secondary beam 4. This coupling contact can effectively reduce stress concentration or eccentric force during the test, and at the same time avoid pressure overshoot, reduce the impact of system deviation on the test results, and improve the stability and reliability of the system.
[0051] like Figure 2 As shown, in some embodiments, a main beam reinforcing plate 7 is provided between the top rod of the hydraulic jack 5 and the bottom surface of the main beam 3.
[0052] like Figure 2 As shown, in some embodiments, in order to accurately detect strain, both the compression pile and the reaction pile are equipped with a large-range dial gauge 9. The large-range dial gauge 9 is mounted on a standard frame to measure the settlement of the compression pile 1 and the uplift of the reaction pile 2.
[0053] like Figure 2 As shown, in some embodiments, concrete supports 10 are respectively placed at both ends of the bottom surface of the main beam 3 to prevent overturning and falling.
[0054] like Figure 2-4 As shown, in some embodiments, the anchoring structure includes an anchor plate 8, an anchor cable, and an anchor bolt 12. The anchor plate 8 is disposed on the top surface of the end of the secondary beam 4. The upper end of the anchor cable passes through the end of the secondary beam 4 and is connected to the anchor plate 8 through the anchor bolt 12. The lower end of the anchor cable is connected to the reaction pile 2.
[0055] like Figure 4 As shown, in some embodiments, the anchor cable includes a tensile anchor bolt 13, a butt bolt 14, and an anchor bar 15 connected sequentially from top to bottom. The tensile anchor bolt 13 is connected to the anchor plate 8 via the anchor bolt 12, and the anchor bar 15 is connected to the reaction pile 2. The secondary beam 4 is installed on the main beam 3, and the tensile anchor bolt 13 is connected to the secondary beam 4 via the square anchor plate 8 and the anchor bolt 12 to lock the secondary beam 4 in place.
[0056] In some embodiments, the hydraulic jack 5 is preferably connected to a pressure gauge. The pressure gauge is mounted on the hydraulic jack and is used to measure the test load during the test.
[0057] When selecting this reaction system device, the cross-sectional properties and structural stability of the main beam 3 and secondary beam 4 should be verified based on the test load, and the number of anchor bars 15 should be calculated. Sufficient guarantee factors should be considered during the system calculation and verification process to ensure the stability and reliability of the system.
[0058] Before the formal commencement of the single pile vertical static load test, a systematic inspection should be conducted and pre-loading measures should be taken. The operation method is the same as the formal loading method: apply pressure to 15% of the test load using jack 5, hold the pressure for 1 minute, and then release the pressure. After the pressure is released, reset all measuring instruments 9 to zero.
[0059] This invention first designs a composite box girder structure based on the reaction force values and system load combinations required for the experiment. Shear force and bending moment of the beam are obtained through simulation calculations. Then, the maximum stress is obtained through shear force and bending moment analysis and compared with the material's ultimate strength. Deflection is verified based on the material's strength, elastic modulus, and beam cross-sectional dimensional characteristics to obtain the maximum deformation, which is then compared with the material's ultimate deformation to ensure the stability and reliability of the structural design. Based on the distribution of the test load on the reaction piles, the number and configuration of anchor bars are determined by calculating the ultimate tensile force of a single anchor bar.
[0060] The advantages of this invention compared to the prior art are as follows:
[0061] This utility model utilizes a composite box girder and reaction piles to ingeniously and efficiently convert the reaction force provided by the reaction piles into the reaction force required for testing. It can simultaneously measure the compressive bearing capacity of the compression piles and the tensile strength of the reaction piles, enabling comprehensive testing and evaluation of pile foundation performance. It makes full use of site conditions, improves and upgrades existing technologies and reaction device forms, and effectively solves the problems and shortcomings of existing technologies. It shows great advantages in saving costs, improving efficiency, reducing resource consumption, and reducing energy consumption, and is not limited by site conditions or loading tonnage, thus possessing great practical value and economic benefits.
[0062] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.
Claims
1. A reaction device for static load testing of cast-in-place piles, characterized in that, include: A pile structure, comprising compression piles and reaction piles; The beam structure includes a main beam and a secondary beam. Two secondary beams are respectively erected at both ends of the top surface of the main beam. The reaction piles are respectively arranged below the two ends of the secondary beams. The reaction piles are anchored to the ends of the secondary beams through an anchoring structure. A hydraulic jack, wherein the jack rod is mounted on the bottom surface of the main beam, and the anti-compression pile is mounted on the bottom of the hydraulic jack; The centering limiting assembly includes angle steel, adjusting bolts, a first limiting locking rod, a second limiting locking rod, and limiting fixing bolts. Angle steel is provided at each of the four intersection points of the secondary beam and the main beam. The lower part of one side plate of each of the four angle steels is connected to the main beam via limiting fixing bolts. The upper part of the other side plate of each of the four angle steels is connected to the secondary beam via adjusting bolts. The lower part of one side plate of the front and rear angle steels is locked and connected via limiting locking rods passing through the main beam. The upper part of one side plate of the front and rear angle steels is locked and connected via limiting locking rods passing through the secondary beam.
2. The reaction device for static load testing of cast-in-place piles according to claim 1, characterized in that, A pad is provided between the top surface of the anti-compression pile and the bottom surface of the hydraulic jack, and a first coupling sand layer is provided between the pad and the bottom surface of the hydraulic jack. The first coupling sand layer is a standard sand layer.
3. The reaction device for static load testing of cast-in-place piles according to claim 1, characterized in that, A second coupling sand layer is provided between the top two ends of the main beam and the secondary beam, and the second coupling sand layer is a standard sand layer.
4. The reaction device for static load testing of cast-in-place piles according to claim 1, characterized in that, A main beam reinforcing plate is provided between the top rod of the hydraulic jack and the bottom surface of the main beam.
5. The reaction device for static load testing of cast-in-place piles according to claim 1, characterized in that, Both the compression pile and the reaction pile are equipped with a large-scale dial gauge on their top surfaces.
6. The reaction device for static load testing of cast-in-place piles according to claim 1, characterized in that, Concrete supports are provided at both ends of the bottom surface of the main beam.
7. The reaction device for static load testing of cast-in-place piles according to claim 1, characterized in that, The anchoring structure includes an anchor plate, an anchor cable, and an anchor bolt. The anchor plate is disposed on the top surface of the end of the secondary beam. The upper end of the anchor cable passes through the end of the secondary beam and is connected to the anchor plate through the anchor bolt. The lower end of the anchor cable is connected to the reaction pile.
8. The reaction device for static load testing of cast-in-place piles according to claim 7, characterized in that, The anchor cable includes a tensile anchor bolt, a butt bolt, and an anchor bar connected in sequence from top to bottom. The tensile anchor bolt is connected to the anchor plate through the anchor bolt, and the anchor bar is connected to the reaction pile.
9. The reaction device for static load testing of cast-in-place piles according to claim 1, characterized in that, The hydraulic jack is connected to an oil pressure gauge.