Static load test device and static load test method for water pile foundation

Abstract

The invention discloses an overwater pile foundation static load test device and a static load test method, and relates to the related technical field of pile foundation tests.The overwater pile foundation static load test device comprises a first pile embracing piece and a second pile embracing piece, and the first pile embracing piece and the second pile embracing piece rotate with the center part as the axis; an X-shaped four-point enclasping structure is formed through the first pile embracing piece and the second pile embracing piece; stress blocks are arranged on the opposite sides of the tops of the first pile holding piece and the second pile holding piece; the bottom cylinders are fixed to the two ends of the bottom of the I-shaped beam, and the first pile embracing pieces or the second pile embracing pieces are connected with the bottom cylinders through hanging pieces; the locking cylinder is installed at the bottom of the bottom cylinder through a lifting assembly and is coaxially arranged with the locking cylinder, and the locking cylinder is matched with the first pile holding piece, the second pile holding piece and the stress block; a three-stage constraint structure of four-point clasping of the X-shaped double-pile clasping piece, radial self-locking of the locking barrel and clamping of the stress block is adopted, the pile clasping piece can be completely prevented from opening and sliding under the test heavy load, and stable counterforce transmission of the auxiliary pile is guaranteed.

Description

Technical Field

[0001] This invention relates to the technical field of pile foundation testing, specifically to a static load testing device and method for underwater pile foundations. Background Technology

[0002] In marine and water-related engineering projects such as offshore wind power, floating photovoltaic power, and cross-sea bridges, pile foundations are the core load-bearing components that ensure structural safety. Their load-bearing capacity needs to be accurately verified through static load tests, which is a crucial step in evaluating pile foundation performance and ensuring project quality. Static load tests on offshore pile foundations rely on auxiliary piles to provide reaction force. The pile clamping and locking device, as the core component connecting the test equipment and the auxiliary piles, directly determines the test accuracy and operational efficiency in terms of its reliability, adaptability, and safety.

[0003] Existing static load testing devices for underwater pile foundations generally suffer from technical defects, making it difficult to meet the demands of complex underwater working conditions. The existing technology, represented by a static load testing device for vertical compressive strength of a single underwater pile (authorization announcement number CN217651869U), and similar devices all exhibit the following prominent problems: Existing devices mostly employ a two-point clamping or single-locking structure, lacking a graded constraint design. This device uses a simple support and pad, without a dedicated pile clamping and locking mechanism. Under heavy loads during testing, the clamping components are prone to opening and slipping relative to the auxiliary pile, leading to unstable reaction force transmission and distorted test data. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a static load testing device and method for underwater pile foundations, which solves the problem that the pile clamping member may open and slip relative to the auxiliary pile when heavy loads are applied during the test.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a static load testing device for underwater pile foundations, comprising an I-beam located above the test pile and jacks located between the I-beam and the test pile. The two ends of the I-beam are fixed to the upper ends of an auxiliary pile via a clamping mechanism, the clamping mechanism comprising: The No. 1 and No. 2 pile clamps rotate around the central part as an axis, forming four X-shaped clamping surfaces; force-bearing blocks are provided on opposite sides of the top of the No. 1 and No. 2 pile clamps. The bottom cylinder is fixed to both ends of the bottom of the I-beam, and the No. 1 or No. 2 pile clamp is connected to the bottom cylinder through a suspension component. The locking cylinder is installed at the bottom of the bottom cylinder via a lifting assembly and is coaxially arranged with the locking cylinder. The locking cylinder cooperates with the No. 1 pile clamp, the No. 2 pile clamp, and the force-bearing block. The auxiliary pile is gripped by the relative rotation of the No. 1 and No. 2 pile gripping components, and the No. 1 and No. 2 pile gripping components are locked by the rising of the locking cylinder.

[0006] Furthermore, the clamping surface is configured in a split manner, including two main frames on both sides and multiple movable parts located within the two main frames and installed radially via connectors; The connector is made of an elastic material.

[0007] Furthermore, both the No. 1 and No. 2 pile clamps are provided with anti-slip teeth that are equidistantly arranged on opposite sides; The anti-slip teeth are wedge-shaped or conical.

[0008] Furthermore, the bottom of the locking cylinder is provided with a base plate integrally formed therewith, and pin holes are provided on both the first and second pile clamping components. Through holes are provided in the I-beam, bottom cylinder, and bottom support plate. Locking components are inserted into the pin holes, I-beam, bottom cylinder, locking cylinder, and through holes. The locking components are U-shaped.

[0009] Furthermore, the lifting assembly includes multiple tie rods that pass through the I-beam and the bottom cylinder and are rotatably connected to the I-beam and the bottom cylinder, and the locking cylinder has a threaded hole that engages with the tie rod.

[0010] Furthermore, triggering components can be detachably and slidably installed on the I-beam and the bottom cylinder, and the triggering components cooperate with the No. 1 pile clamping component and the No. 2 pile clamping component; The distance between the upper sides of the No. 1 and No. 2 pile clamps is less than the distance between the lower sides. The triggering element includes an I-beam plate, with four pressure plates fixed at the bottom of the I-beam plate.

[0011] Furthermore, slots are provided at both ends of the top of the I-beam.

[0012] Furthermore, the force-bearing block is arranged in an isosceles trapezoidal shape, with its narrow face facing the center of the auxiliary pile.

[0013] Furthermore, the distance between the top two sides of the No. 1 and No. 2 pile clamps and the distance between the bottom two sides is 2cm.

[0014] The present invention also provides a method for static load testing of underwater pile foundations, using the aforementioned underwater pile foundation static load testing device, comprising the following steps: Step 1: Use lifting equipment and steel cables to lift the I-beam, align the jacks with the test pile, and align the bottom cylinder with the auxiliary piles on both sides of the test pile. Lower the I-beam until the jacks reach the top of the test pile and the bottom cylinder reaches the top of the auxiliary piles. The No. 1 and No. 2 pile clamps open and fit into the outside of the test pile under the action of gravity. Step 2: Drive the No. 1 and No. 2 pile-holding components to rotate relative to each other by external force or triggering device to form four clamping surfaces for the test pile; Step 3: Drive the locking cylinder to rise through the lifting assembly to apply radial constraints to the No. 1 and No. 2 pile clamping components to achieve self-locking. Insert the locking component for further reinforcement to ensure that the No. 1 and No. 2 pile clamping components remain in a tight clamping state. Step 4: Apply axial pressure to the top of the test pile using jacks. The reaction force is transmitted to the auxiliary pile through the I-beam, and the settlement of the test pile is detected by testing equipment. Step 5: After the test is completed, loosen the No. 1 and No. 2 pile clamps, and then lift the I-beam away.

[0015] The present invention has the following beneficial effects: I. The static load test device for underwater pile foundations adopts a three-level constraint structure with four clamping surfaces of X-shaped double-clamping pile members, radial self-locking of the locking cylinder, and clamping of the force-bearing block. It can completely prevent the clamping pile members from opening and slipping under heavy load test, and ensure the stable transmission of the auxiliary pile reaction force. It solves the problem of unreliable clamping in the static load test of underwater pile foundations from a structural point of view.

[0016] II. The static load test device for underwater pile foundations has elastic connectors and self-adaptive moving parts inside the pile clamping component. It can automatically conform to the slight unevenness of the pile surface, increase the clamping contact area, disperse the force, avoid stress concentration, and maintain the clamping pressure for a long time, thus greatly improving the clamping life for different pile surfaces.

[0017] Third, this static load test device for underwater pile foundations, through the interference fit of wedge-shaped / conical anti-slip teeth and locking cylinder, forms a micro-anchoring interlocking structure at the interface of the pile foundation clamping component, which significantly improves the anti-slip static friction force, and can achieve strong constraint without significant damage to the pile body, taking into account both clamping strength and pile integrity.

[0018] IV. The static load test device for underwater pile foundation adopts a multi-rod synchronous meshing drive to lift and lower the locking cylinder. A single point drive can drive multiple bolts to rotate synchronously. The drive is labor-saving, simple in structure, and low in cost. The locking or unlocking action is precise and controllable, which greatly improves the efficiency of the installation, disassembly and debugging of the underwater test device.

[0019] V. This static load test device for water-based pile foundations, through the U-shaped locking component that penetrates multiple components for rigid locking and the isosceles trapezoidal self-centering force block, not only achieves redundant locking in the clamped state to prevent accidental slippage, but also has self-centering and anti-vibration loosening capabilities, significantly improving the safety of operations at high altitudes and in complex working conditions on water.

[0020] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 for Figure 1A structural diagram from another direction; Figure 3 This is a structural schematic diagram of another state of the present invention; Figure 4 for Figure 3 Enlarged view of the local structure at point A; Figure 5 This is a schematic diagram showing the cooperation between the trigger and locking components and the first and second pile-holding components in this invention. Figure 6 This is a schematic diagram of the structure of the No. 1 and No. 2 pile clamping components in this invention; Figure 7 for Figure 6 Enlarged view of the local structure at point B; Figure 8 This is a schematic diagram of the connector structure in this invention; Figure 9 This is a schematic diagram showing the cooperation between the No. 1 and No. 2 pile clamping components and the locking cylinder in this invention; Figure 10 This is a cross-sectional view of the locking cylinder in this invention; Figure 11 This is a schematic diagram of the bottom cylinder of the present invention; Figure 12 This is a top view of the No. 1 and No. 2 pile clamping components in this invention.

[0022] In the diagram: 1. I-beam; 101. Through groove; 102. Groove opening; 103. Hook and hanger; 2. Bottom cylinder; 3. Locking cylinder; 301. Screw hole; 302. Bottom support plate; 303. Through hole; 4. No. 1 pile clamping component; 401. No. 2 pile clamping component; 402. Suspension component; 403. Pin hole; 404. Moving component; 405. Clamping part; 406. Load-bearing block; 407. Anti-slip teeth; 408. Connecting component; 5. Auxiliary pile; 6. Triggering component; 7. Locking component; 8. Jack; 9. Tie rod. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] In the description of this invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inner", "around", etc., which indicate orientation or positional relationship, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting this invention.

[0025] The following is based on Figures 1-12 This invention describes the static load testing device for underwater pile foundations provided in an embodiment of the invention.

[0026] like Figures 1-12 As shown, this embodiment of the invention provides a technical solution: a static load testing device for underwater pile foundations, including an I-beam 1 located above the test pile and jacks 8 located between the I-beam 1 and the test pile. Both ends of the I-beam 1 are fixed to the upper ends of an auxiliary pile 5 by a clamping mechanism. The clamping mechanism includes: The No. 1 pile clamping component 4 and the No. 2 pile clamping component 401 rotate around the central part as an axis, forming four X-shaped clamping surfaces; a force-bearing block 406 is provided on the opposite side of the top of the No. 1 pile clamping component 4 and the No. 2 pile clamping component 401. The bottom cylinder 2, which is fixed to both ends of the bottom of the I-beam 1, is connected to the bottom cylinder 2 by either the No. 4 or No. 2 pile clamping component 401 through the suspension component 402. The locking cylinder 3 is installed at the bottom of the bottom cylinder 2 via a lifting assembly and is coaxially arranged with the locking cylinder 3. The locking cylinder 3 cooperates with the first pile clamp 4, the second pile clamp 401, and the force-bearing block 406. The auxiliary pile 5 is gripped by the relative rotation of the first pile gripper 4 and the second pile gripper 401, and the first pile gripper 4 and the second pile gripper 401 are locked by the rising of the locking cylinder 3.

[0027] In this embodiment of the invention, a plurality of hooks 103 are fixed on the I-beam 1, and steel cables are installed on the hooks 103. The lifting equipment lifts the I-beam 1 through the steel cables and places the I-beam 1 in a designated position.

[0028] During the test, the jack 8 is placed above the auxiliary pile 5 to be tested, and then the bottom cylinder 2 is placed above the auxiliary pile 5. Subsequently, the I-beam 1 is lowered so that the jack 8 abuts against the top of the pile to be tested, and the bottom cylinder 2 abuts against the top of the auxiliary pile 5. At this time, the first pile clamp 4 and the second pile clamp 401 automatically open and fit into the outer circumference of the test pile under the action of gravity. Then, the first pile clamp 4 and the second pile clamp 401 are driven by external force to rotate relative to each other at the pivot point so as to clamp the test pile tightly through the first pile clamp 4 and the second pile clamp 401.

[0029] After clamping is completed, the lifting assembly drives the locking cylinder 3 to rise. The inner wall of the locking cylinder 3 applies radial constraint to the outer walls of the first pile clamping member 4 and the second pile clamping member 401, achieving mechanical self-locking. This keeps the first pile clamping member 4 and the second pile clamping member 401 in a clamped state, ensuring no displacement of the pile body during the test. When the locking cylinder 3 rises to the end of its stroke, it abuts against the bottom of the force-bearing block 406. The locking cylinder 3 and the bottom cylinder 2 clamp the force-bearing block 406 of the first pile clamping member 4 and the second pile clamping member 401, further restricting the second pile clamping member 401 and the first pile clamping member 4 from opening during the test.

[0030] During the application of heavy loads, since the I-beam 1 is fixed to the auxiliary pile 5 by the clamping and locking structure, the axial pressure is applied to the top of the test pile when the jack 8 exerts force, while the reaction force is evenly transmitted to the foundation through the auxiliary pile 5.

[0031] The clamping surface is configured in a split manner, including two main frames on both sides and multiple movable parts 404 located within the two main frames and installed radially via connectors 408; The connector 408 is made of an elastic material.

[0032] In this embodiment of the invention, when the No. 2 pile clamping member 401 and the No. 1 pile clamping member 4 clamp the test pile, the radial movement of the movable member 404 relative to the auxiliary pile 5 can increase the contact area between the clamping part 405 of the No. 1 pile clamping member 4 and the No. 2 pile clamping member 401 and the auxiliary pile 5, thereby improving the clamping force and the coefficient of friction; the connector 408 made of elastic material deforms when compressed, so that the movable member 404 can adapt to the slight unevenness of the pile surface, ensuring uniform force transmission and no stress concentration.

[0033] The connector 408 can be made of rubber, which has excellent elastic recovery and wear resistance, and can maintain the contact pressure between the movable part 404 and the pile body for a long time. During repeated tightening and loosening cycles, the deformation of the connector 408 is stable and its fatigue life is long. Of course, other materials can also be used, and this invention does not impose specific limitations.

[0034] Both the No. 4 and No. 401 pile clamps are provided with anti-slip teeth 407 arranged at equal intervals on opposite sides. The anti-slip teeth 407 are wedge-shaped or conical.

[0035] In this embodiment of the invention, the wedge-shaped or conical anti-slip teeth 407 embed themselves into tiny depressions along the radial direction of the pile body during the pile gripping process, enhancing the micro-interlocking effect and significantly improving static friction and anti-slip capability.

[0036] The outer sides of the No. 1 pile clamp 4 and the No. 2 pile clamp 401 are arc-shaped and fit the inner wall of the locking cylinder 3. When the locking cylinder 3 is fitted outside the No. 1 pile clamp 4 and the No. 2 pile clamp 401, the two are interference fit to ensure that the pile clamps do not slide relative to each other under axial load; the arc-shaped outer contour fits tightly with the inner wall of the auxiliary pile 5.

[0037] Since the No. 2 pile clamping component 401 and the No. 1 pile clamping component 4 are interference fit with the locking cylinder 3, the anti-slip teeth 407 can apply directional extrusion force to the pile surface, forming a slight biting and embedding on the pile surface, thereby forming a micro-anchoring structure at the pile-pile clamping component interface, further suppressing relative slippage.

[0038] The bottom of the locking cylinder 3 is provided with an integrally formed bottom support plate 302, and the first pile clamping component 4 and the second pile clamping component 401 are both provided with pin holes 403. Through holes 303 are provided on the I-beam 1, the bottom cylinder 2, and the bottom support plate 302. Locking parts 7 are inserted into the pin hole 403, the I-beam 1, the bottom cylinder 2, the locking cylinder 3, and the through holes 303. The locking parts 7 are arranged in a U-shape.

[0039] In this embodiment of the invention, the pin holes 403 on the second pile clamping member 401 and the first pile clamping member 4 are coaxial after the auxiliary pile 5 is clamped; the through holes 303 on the I-beam 1, the bottom cylinder 2, and the locking cylinder 3 are coaxially arranged. The locking element 7 passes sequentially through the I-beam 1, the bottom cylinder 2, the pin hole 403, and the through hole 303, achieving synchronous locking of multiple components through rigid constraint. This allows for precise application of axial preload to the first pile clamping element 4 and the second pile clamping element 401. Even after the locking cylinder 3 disengages, the first pile clamping element 4 and the second pile clamping element 401 maintain a stable clamping state, effectively preventing accidental slippage of the pile. The U-shaped pin locking element 7 has self-locking protrusions at both ends, which, after being embedded in the groove at the end of the through hole 303, form a one-way anti-slip structure.

[0040] Among them, the bottom support plate 302 not only provides structural support for the locking cylinder 3, but also disperses the concentrated downward load of the locking cylinder 3 through its horizontal bearing surface, avoiding excessive local stress that could lead to micro-deformation of the pile body.

[0041] It should also be noted that the I-beam 1 has a through groove 101, which is used for the installation of the locking component 7.

[0042] The lifting assembly includes multiple tie rods 9 that pass through the I-beam 1 and the bottom cylinder 2 and are rotatably connected to the I-beam 1 and the bottom cylinder 2. The locking cylinder 3 has a screw hole 301 that is threaded to the tie rod 9.

[0043] In this embodiment of the invention, the pull rod 9 is driven to rotate by a related tool, and the threaded engagement between the pull rod 9 and the screw hole 301 drives the locking cylinder 3 to rise or fall vertically. like Figures 1-3 As shown, when the locking cylinder 3 is at its highest position, the pull rod 9 is partially extended from the bottom of the locking cylinder 3; when the locking cylinder 3 is at its lowest position, the pull rod 9 only partially engages with the screw hole 301 of the locking cylinder 3. When the locking cylinder 3 is at its highest position, it locks the first pile clamping member 4 and the second pile clamping member 401; when it is at its lowest position, it releases the locking of the first pile clamping member 4 and the second pile clamping member 401, allowing them to rotate in opposite directions and releasing the clamping of the auxiliary pile 5.

[0044] This driving method has the advantages of being simple to drive, requiring little effort, and having low cost.

[0045] The I-beam 1 and the bottom cylinder 2 are also detachably and slidably equipped with triggering components 6, which cooperate with the first pile clamping component 4 and the second pile clamping component 401. The distance between the upper sides of pile clamp 4 and pile clamp 401 is less than the distance between the lower sides. The triggering component 6 includes an I-beam plate, with four pressure plates fixed to the bottom of the I-beam plate. As the pressure plates slide along the I-beam beam 1 with the I-beam plate, they precisely press against the upper outer slope of the first pile clamping component 4 and the second pile clamping component 401.

[0046] In this embodiment of the invention, by pressing the trigger 6 with external force, the trigger 6 is made to stand upright and descend, so that the trigger 6 (pressure plate) presses the lower part of the first pile clamping member 4 and the second pile clamping member 401, thereby causing the first pile clamping member 4 and the second pile clamping member 401 to rotate relative to each other, thus achieving the clamping of the auxiliary pile 5; as Figure 5 As shown.

[0047] When the trigger 6 is pulled by an external force, since the first pile clamp 4 and the second pile clamp 401 are both equipped with force-bearing blocks 406 on their upper parts, and the weight of the upper part is greater than that of the lower part, the second pile clamp 401 and the first pile clamp 4 will easily rotate in opposite directions when there is vibration and external force, thus releasing the clamp on the auxiliary pile 5.

[0048] The top two ends of the I-beam 1 are provided with slots 102.

[0049] In this embodiment of the invention, the slot 102 makes it easier to place a hand or tool under the trigger 6 when disassembling the trigger 6, thus making it easier to remove the trigger 6.

[0050] The force-bearing block 406 is arranged in an isosceles trapezoidal shape, with its narrow face facing the center of the auxiliary pile 5.

[0051] In this embodiment of the invention, the force-bearing block 406 is configured as an isosceles trapezoid. The design with the narrow face facing the center of the auxiliary pile 5 allows the force-bearing block 406 to more accurately conform to the curved surface of the pile during rotation, enhancing the guidance and self-centering ability when clamping; at the same time, the trapezoidal structure generates slight elastic deformation when under pressure, improving contact stability and effectively suppressing accidental loosening caused by vibration.

[0052] The difference between the distance between the top two sides of the No. 1 pile clamp 4 and the bottom two sides of the No. 2 pile clamp 401 is 2cm.

[0053] On the other hand, embodiments of the present invention also provide a method for static load testing of underwater pile foundations, using the aforementioned static load testing device for underwater pile foundations, including the following steps: Step 1: Lift the I-beam 1 with the help of the lifting equipment and steel cable, align the jack 8 with the test pile, and align the bottom cylinder 2 with the auxiliary piles 5 on both sides of the test pile. Lower the I-beam 1 until the jack 8 touches the top of the test pile and the bottom cylinder 2 touches the top of the auxiliary piles 5. The No. 1 pile clamp 4 and the No. 2 pile clamp 401 open and fit into the outside of the test pile under the action of gravity. Step 2: Drive the No. 1 pile clamping component 4 and the No. 2 pile clamping component 401 to rotate relative to each other by external force or triggering component 6, so as to form four clamping surfaces for the test pile; Step 3: Drive the locking cylinder 3 to rise through the lifting assembly to implement radial constraint on the No. 1 pile clamping component 4 and the No. 2 pile clamping component 401 to achieve self-locking. Insert the locking component 7 for further reinforcement to ensure that the No. 1 pile clamping component 4 and the No. 2 pile clamping component 401 remain in a tight clamping state. Step 4: Apply axial pressure to the top of the test pile using jack 8. The reaction force is transmitted to the auxiliary pile 5 through I-beam 1, and the settlement of the test pile is detected by the testing equipment. Step 5: After the test is completed, remove the locking component 7, use the lifting assembly to lower the locking cylinder 3 to release the self-locking, release the No. 1 pile clamp 4 and the No. 2 pile clamp 401, and then lift the I-beam 1 away.

[0054] During use (operation), firstly, steel cables are installed through the hooks 103 on the I-beam 1. The I-beam 1 is then lifted and precisely positioned using lifting equipment, so that the jacks 8 at the bottom are aligned with the top of the pile to be tested (test pile). At the same time, the bottom cylinders 2 at both ends of the I-beam 1 are placed on the top of the auxiliary piles 5 on both sides of the test pile. Then, the I-beam 1 is slowly lowered, so that the jacks 8 are tightly against the top of the test pile and the bottom cylinders 2 are stably against the top of the auxiliary piles 5. At this time, the first pile clamp 4 and the second pile clamp 401 automatically open under their own weight and smoothly fit into the outer circumference of the test pile. Next, by pressing the trigger 6, which is detachably and slidably installed on the I-beam 1 and the bottom cylinder 2, the pressure plate of the trigger 6 presses down on the lower part of the two pile clamping parts, driving the No. 1 pile clamping part 4 and the No. 2 pile clamping part 401 to rotate relative to each other around the central axis, forming an X-shaped four-point clamping structure. During the pile clamping process, the movable part 404 on the pile clamping part adapts to the slight unevenness of the pile surface under the action of the elastic connecting part 408, increasing the contact area with the pile body. The wedge-shaped or conical anti-slip teeth 407 are embedded in the slight depressions of the pile body to form a micro-engagement, further improving the clamping force and anti-slip capability. After the clamping is completed, the pull rod 9 in the lifting assembly is rotated. Through the threaded engagement between the pull rod 9 and the screw hole 301 of the locking cylinder 3, the locking cylinder 3 is driven to rise coaxially along the bottom cylinder 2. The inner wall of the locking cylinder 3 is interference-fitted with the arc-shaped outer side of the pile clamping component, which applies radial constraint to the first pile clamping component 4 and the second pile clamping component 401 to achieve mechanical self-locking. At the same time, after the locking cylinder 3 rises to the end of its stroke, it abuts against the bottom of the force receiving block 406 and clamps the force receiving block 406 together with the bottom cylinder 2, further restricting the opening of the pile clamping component. Then, the U-shaped locking component 7 is passed through the I-beam 1, the bottom cylinder 2, the pin hole 403 of the pile clamping component and the coaxial through hole 303 of the locking cylinder 3 in sequence. Through rigid constraint, multiple components are locked synchronously. Even if the locking cylinder 3 is disengaged, it can maintain a stable clamping state and prevent the pile from slipping out unexpectedly. During the heavy load test, since the I-beam 1 is fixed to the auxiliary pile 5 through the pile clamping and locking structure, the jack 8 applies axial pressure to the top of the test pile, and the reaction force generated by the pressure is transmitted to the auxiliary pile 5 through the I-beam 1 and the bottom cylinder 2, and then evenly transmitted to the foundation by the auxiliary pile 5, ensuring that the pile body has no displacement and the force is transmitted evenly during the test, thus completing the static load test of the pile foundation. After the test, the locking part 7 is removed, the pull rod 9 is rotated in the opposite direction to lower the locking cylinder 3 to release the self-locking, and the trigger part 6 is pulled. Taking advantage of the weight of the upper force block 406 of the pile clamping part, the first pile clamping part 4 and the second pile clamping part 401 are rotated in opposite directions to release the clamping on the test pile, thus completing the disassembly of the equipment.

[0055] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0056] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A static load testing device for underwater pile foundations, comprising an I-beam (1) located above the test pile and jacks (8) located between the I-beam (1) and the test pile, characterized in that, The two ends of the I-beam (1) are fixed to the upper end of the auxiliary pile (5) by a clamping mechanism, which includes: The No. 1 pile clamping component (4) and the No. 2 pile clamping component (401) rotate around the central part as an axis, forming four X-shaped clamping surfaces through the No. 1 pile clamping component (4) and the No. 2 pile clamping component (401); a force-bearing block (406) is provided on the opposite side of the top of the No. 1 pile clamping component (4) and the No. 2 pile clamping component (401). The bottom cylinder (2) is fixed to both ends of the bottom of the I-beam (1), and the No. 1 pile clamp (4) or the No. 2 pile clamp (401) is connected to the bottom cylinder (2) through the suspension member (402); The locking cylinder (3) is installed at the bottom of the bottom cylinder (2) through the lifting assembly and is coaxially arranged with the locking cylinder (3). The locking cylinder (3) cooperates with the first pile clamp (4), the second pile clamp (401) and the force block (406). The auxiliary pile (5) is gripped by the relative rotation of the No. 1 pile gripper (4) and the No. 2 pile gripper (401), and the No. 1 pile gripper (4) and the No. 2 pile gripper (401) are locked by the rise of the locking cylinder (3).

2. The static load testing device for underwater pile foundations according to claim 1, characterized in that, The clamping surface is configured in a split manner, including the main frames on both sides and a plurality of movable parts (404) located in the two main frames and installed radially through the connector (408). The connector (408) is made of an elastic material.

3. The static load testing device for underwater pile foundations according to claim 1, characterized in that, The first pile clamp (4) and the second pile clamp (401) are provided with anti-slip teeth (407) arranged at equal intervals on opposite sides. The anti-slip teeth (407) are wedge-shaped or conical.

4. The static load testing device for underwater pile foundations according to claim 1, characterized in that, The bottom of the locking cylinder (3) is provided with a bottom support plate (302) integrally formed therewith, and the first pile clamp (4) and the second pile clamp (401) are both provided with pin holes (403). Through holes (303) are provided on the I-beam (1), bottom cylinder (2), and bottom support plate (302). Locking parts (7) are inserted into the pin hole (403), I-beam (1), bottom cylinder (2), locking cylinder (3), and through holes (303). The locking parts (7) are U-shaped.

5. The static load testing device for underwater pile foundations according to claim 1, characterized in that, The lifting assembly includes multiple pull rods (9) that pass through the I-beam (1) and the bottom cylinder (2) and are rotatably connected to the I-beam (1) and the bottom cylinder (2). The locking cylinder (3) has a screw hole (301) that is threaded to the pull rod (9).

6. The static load testing device for underwater pile foundations according to claim 1, characterized in that, The I-beam (1) and the bottom cylinder (2) are also detachably and slidably equipped with triggering components (6), which cooperate with the first pile clamping component (4) and the second pile clamping component (401); The distance between the upper sides of the No. 1 pile clamp (4) and the No. 2 pile clamp (401) is less than the distance between the lower sides; Among them, the trigger (6) includes an I-beam plate, and four pressure plates are fixed at the bottom of the I-beam plate.

7. The static load testing device for underwater pile foundations according to claim 6, characterized in that, The top two ends of the I-beam (1) are provided with slots (102).

8. The static load testing device for underwater pile foundations according to claim 2, characterized in that, The force-bearing block (406) is arranged in an isosceles trapezoidal shape, with its narrow face facing the center of the auxiliary pile (5).

9. The static load testing device for underwater pile foundations according to claim 6, characterized in that, The difference between the distance between the top two sides of the No. 1 pile clamp (4) and the bottom two sides of the No. 2 pile clamp (401) is 2cm.

10. A method for static load testing of underwater pile foundations, employing the underwater pile foundation static load testing apparatus as described in any one of claims 1-9, characterized in that, Includes the following steps: Step 1: Lift the I-beam (1) with the help of the lifting equipment and steel cable, align the jack (8) with the test pile, and align the bottom cylinder (2) with the auxiliary piles (5) on both sides of the test pile. Lower the I-beam (1) until the jack (8) abuts the top of the test pile and the bottom cylinder (2) abuts the top of the auxiliary pile (5). The No. 1 pile clamp (4) and the No. 2 pile clamp (401) open and fit into the outside of the test pile under the action of gravity. Step 2: Drive the No. 1 pile clamping component (4) and the No. 2 pile clamping component (401) to rotate relative to each other by external force or triggering component (6) to form four clamping surfaces for the test pile; Step 3: Drive the locking cylinder (3) to rise through the lifting assembly, implement radial constraint on the No. 1 pile clamping component (4) and the No. 2 pile clamping component (401) to achieve self-locking, insert the locking component (7) for further reinforcement, and ensure that the No. 1 pile clamping component (4) and the No. 2 pile clamping component (401) remain in a clamped state; Step 4: Apply axial pressure to the top of the test pile using jacks (8), and transmit the reaction force to the auxiliary pile (5) through the I-beam (1). Detect the settlement of the test pile using testing equipment. Step 5: After the test is completed, loosen the No. 1 pile clamp (4) and the No. 2 pile clamp (401), and the lifting equipment can move the I-beam (1).

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