Method of construction of precast pile cap structure for platformless underwater construction

Abstract

The present application relates to the technical field of high-pile beam slab wharf construction, and discloses a construction method of a prefabricated pile cap structure for platform-free underwater construction, the underwater prefabricated pile cap comprising: a pile cap body, a pile foundation structure is arranged at the bottom of the pile cap body, the pile cap body is connected with the pile foundation structure through concrete grouting, a hoop mechanism is sleeved on the surface of the pile foundation structure close to the top, the top of the hoop mechanism is attached to the pile cap body, and a corrugated pipe is arranged in the pile cap body to form a grouting space integrally. The construction method comprises the following steps: S1, starting pile sinking, and processing the pile foundation structure and the pile core cage; S2, hoisting the pile cap body on the top of the pile foundation structure, and leveling; S3, setting the corresponding hoop mechanism according to the inclination of the pile foundation structure, and pressing and attaching it below the pile cap body; and S4, underwater grouting construction.

Description

Technical Field

[0001] This invention relates to the field of high-pile beam-slab wharf construction technology, specifically to a construction method for a precast pile cap structure used in platform-less underwater construction. Background Technology

[0002] High-pile wharves are one of the three major structural forms in wharf construction and are widely used in my country. They utilize the load-bearing capacity of piles driven into the foundation to transfer the load-bearing capacity of the superstructure to the depths of the foundation. Then, pile caps need to be installed on the top of the piles to support the wharf itself. Therefore, the construction of pile caps for high-pile wharves has important application value in marine engineering construction.

[0003] The construction of pile cap structures for high-pile beam-slab wharves can be divided into cast-in-place construction and precast pile cap construction methods. In the existing technology, regardless of whether the pile cap construction is cast-in-place or precast, a construction platform needs to be erected as a support and load-bearing system for the pile beams during the construction process. Erecting a platform at the end of the columnar pile beams is quite difficult and affects construction efficiency. In addition, in order to ensure construction quality, construction on the water surface is also required, so the construction is greatly affected by the water level. For the pile cap structure of the wharf close to the water surface, the construction conditions are quite harsh. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a construction method for precast pile cap structures used in platform-free underwater construction, thus solving the problems mentioned in the background.

[0005] This invention provides the following technical solution: a construction method for a precast pile cap structure for platform-free underwater construction. The precast pile cap structure for platform-free underwater construction includes: a pile cap body; a pile foundation structure is provided at the bottom of the pile cap body; the pile cap body is connected to the pile foundation structure by concrete grouting; a clamping mechanism is sleeved on the surface of the pile foundation structure near the top; the top of the clamping mechanism is attached to the pile cap body; a grouting space is integrally formed inside the pile cap body through a corrugated pipe; two grouting holes are opened at the top of the pile cap body, and the two grouting holes lead into the grouting space; a water outlet is opened on the side of the pile cap body; the inner wall of the water outlet penetrates the corrugated pipe to connect the grouting space with the outside; a load-bearing mechanism is provided inside the pile cap body; the top structure of the load-bearing mechanism penetrates the pile cap body and is screwed to it; the bottom structure of the load-bearing mechanism overlaps with the top of the pile foundation structure; and a pile core cage is integrally provided at the top of the pile foundation structure.

[0006] The portion of the pile core cage extending beyond the top of the pile foundation structure is vertically inserted into the grouting space inside the pile cap body.

[0007] The top of the clamping mechanism is horizontally positioned, and the middle part of the clamping mechanism is attached to the surface of the pile foundation structure.

[0008] Its characteristic is that the construction method includes:

[0009] Step S1: Begin pile driving and process the pile foundation structure and pile core cage.

[0010] Step S2: Hoist the pile cap body onto the top of the pile foundation structure and perform leveling.

[0011] Step S3: Set up the corresponding clamping mechanism according to the inclination of the pile foundation structure and press it onto the bottom of the pile cap body;

[0012] Step S4: Perform underwater grouting.

[0013] Preferably, step S1, starting pile driving and processing the pile foundation structure and pile core cage, includes:

[0014] Step S11: Perform pile driving operation according to design requirements;

[0015] Step S12: After pile driving, measure the pile position deviation, slope, torsion angle and elevation.

[0016] Step S13: For inclined piles, according to the designed elevation, the surveyor will cooperate to use an underwater chainsaw to cut the pile head to ensure it is flat.

[0017] Step S14: Process the pile core cage so that its exposed part is arranged vertically.

[0018] Preferably, step S2, which involves hoisting the pile cap body onto the top of the pile foundation structure and performing leveling treatment, includes:

[0019] Step S21: Hoist the pile cap body and insert it into the pile foundation structure.

[0020] Step S22: Use a load-bearing mechanism to support the pile cap body on top of the pile foundation structure;

[0021] Step S23: After the pile cap body is placed and stabilized, the load-bearing mechanism is adjusted according to the specifications of the pile and the pile driving deviation and elevation to make the pile cap body set horizontally.

[0022] Preferably, step S3, which involves setting a corresponding clamping mechanism according to the inclination of the pile foundation structure and pressing it against the underside of the pile cap body, includes:

[0023] Step S31: Make the corresponding clamping mechanism according to the slope of each pile;

[0024] Step S32: The two halves of the clamping mechanism are bolted together and clamped onto the pile foundation structure.

[0025] Step S33: Use the top of the clamping mechanism to press tightly against the bottom of the pile cap body, and at the same time fix the clamping mechanism to the pile foundation structure.

[0026] Preferably, step S4, underwater grouting construction, includes:

[0027] Step S41: Using a guide tube, insert it from the grouting hole to the bottom of the grouting space, leaving a 10cm gap for grouting;

[0028] Step S42: As grouting proceeds, the water in the grouting space is gradually drained from the water outlet as the grouting material fills the outlet. After the grouting material is gradually poured to the elevation of the water outlet, the water outlet is plugged with a wooden plug.

[0029] Step S43: During the grouting process, ensure that the lower end of the guide pipe is always buried in the grout. As the grouting volume increases or decreases, gradually raise the guide pipe until the grouting space is completely filled, and then seal the grouting hole.

[0030] Preferably, the clamping mechanism includes a first clamp plate and a second clamp plate, which are two steel structures joined together. The sides of both the first and second clamp plates are welded with reinforcing plates and clamping plates. The first and second clamp plates are attached together by clamping plates and fixed with bolts. A lifting control ring is rotatably provided at the outer edge of the top of the first and second clamp plates. A lifting mechanism is screwed to the inner wall of the lifting control ring. A sponge is provided on the top of the lifting mechanism, and the sponge is attached to the bottom of the pile cap body.

[0031] Preferably, the lifting mechanism includes a first support piece and a second support piece, which are combined to form a ring structure. The bottom of both the first and second support pieces is welded with a limiting post. The bottom end of the limiting post passes through the first and second hoops and slides with them. A slot is provided at the joint of the second support piece, and an insert is integrally provided at the joint of the first support piece. The insert is inserted into the inside of the slot.

[0032] Preferably, the top of the first hoop and the second hoop are outwardly extending annular platforms, and a groove is provided at the bottom of the annular platform near the outer edge. The lifting ring slides in contact with the inner wall of the groove, and the lifting ring is two hoop rings connected together by bolts.

[0033] Preferably, the load-bearing mechanism includes an I-beam, which overlaps the top of the pile foundation structure. Two supports are provided on the I-beam, and a sliding rod and a screw block are sequentially connected to the top of the supports. A limiting plate is slidably attached to the surface of the sliding rod, and the limiting plate is welded into the pile core cage. An inner screw cylinder is screwed to the outer edge of the top of the screw block, and a rotating rod is integrally provided at the top of the inner screw cylinder. The top of the rotating rod passes through the pile cap body and is provided with an adjusting cap.

[0034] Preferably, the surface of the I-beam is provided with a strip groove and a spiral groove, and the two supports are respectively slidably connected to the inner wall of the strip groove and spirally connected to the inner wall of the spiral groove.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] 1. The construction method for precast pile cap structures used in platform-less underwater construction involves adding corrugated pipes and load-bearing mechanisms inside the pile cap body. The load-bearing mechanism contacts the top of the pile foundation structure inside the pile cap body, thus providing support. This eliminates the need for an external construction platform, significantly reducing construction steps and lowering the requirements for building high-pile wharves. Furthermore, during construction, the position of the load-bearing mechanism can be adjusted according to the specifications of the pile foundation structure and the pile driving deviation and elevation, allowing for fine-tuning of the pile cap body, reducing post-construction errors, and improving the quality of high-pile wharf construction.

[0037] 2. The construction method for the precast pile cap structure used in platform-free underwater construction utilizes a clamping mechanism to seal the joint between the bottom of the pile cap body and the pile foundation structure, allowing the grouting space formed inside the pile cap body to be filled by inserting a pipe into the grouting hole and injecting concrete into the grouting space. This method combines the construction advantages of precast pile caps and cast-in-place pile caps and is applicable to construction below the water level, unaffected by the water level. Attached Figure Description

[0038] Figure 1 This is a flowchart of the construction method for the precast pile cap structure used in platformless underwater construction according to the present invention.

[0039] Figure 2 This is a detailed flowchart of the method in step S1 of the present invention;

[0040] Figure 3 This is a detailed flowchart of step S2 of the present invention;

[0041] Figure 4 This is a detailed flowchart of step S3 of the present invention;

[0042] Figure 5 This is a detailed flowchart of step S4 of the present invention;

[0043] Figure 6 This is a schematic diagram of the overall structure of the present invention;

[0044] Figure 7 This is a schematic diagram of the structure of the present invention from a bottom view;

[0045] Figure 8 This is a schematic diagram of the disassembled structure of the present invention;

[0046] Figure 9 This is a side sectional view of the clamping mechanism of the present invention;

[0047] Figure 10 This is a schematic diagram of the disassembled structure of the clamping mechanism of the present invention;

[0048] Figure 11 This is a schematic diagram of the side section structure of the pile cap body of the present invention;

[0049] Figure 12 This is a side sectional view of the load-bearing mechanism of the present invention.

[0050] In the diagram: 1. Pile cap body; 2. Pile foundation structure; 3. Clamping mechanism; 31. First clamp plate; 32. Second clamp plate; 33. Reinforcing plate; 34. Tightening plate; 35. Control ring; 36. Lifting mechanism; 361. First support plate; 362. Second support plate; 363. Limiting post; 364. Slot; 365. Insert block; 37. Sponge; 4. Water outlet; 5. Grouting hole; 6. Load-bearing mechanism; 61. I-beam; 62. Bracket; 63. Limiting plate; 64. Sliding rod; 65. Threaded block; 66. Inner threaded cylinder; 67. Rotating rod; 68. Adjusting cap; 7. Corrugated pipe; 8. Pile core cage. Detailed Implementation

[0051] 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.

[0052] Please see Figure 1-12 A construction method for a precast pile cap structure for platform-free underwater construction. The precast pile cap structure for platform-free underwater construction includes: a pile cap body 1, a pile foundation structure 2 at the bottom of the pile cap body 1, the pile cap body 1 being connected to the pile foundation structure 2 by concrete grouting, a clamping mechanism 3 being sleeved on the surface of the pile foundation structure 2 near the top, the top of the clamping mechanism 3 being attached to the pile cap body 1, a grouting space integrally formed inside the pile cap body 1 by setting a corrugated pipe 7, two grouting holes 5 being opened at the top of the pile cap body 1 and the two grouting holes 5 being connected to the grouting space, a water outlet hole 4 being opened on the side of the pile cap body 1, the inner wall of the water outlet hole 4 penetrating the corrugated pipe 7 to connect the grouting space to the outside, a load-bearing mechanism 6 being set inside the pile cap body 1, the top structure of the load-bearing mechanism 6 penetrating the pile cap body 1 and being screwed to it, the bottom structure of the load-bearing mechanism 6 overlapping with the top of the pile foundation structure 2, and a pile core cage 8 integrally set at the top of the pile foundation structure 2.

[0053] The portion of the pile core cage 8 extending beyond the top of the pile foundation structure 2 is vertically inserted into the grouting space inside the pile cap body 1;

[0054] The top of the clamping mechanism 3 is horizontally positioned, and the middle part of the clamping mechanism 3 is attached to the surface of the pile foundation structure 2.

[0055] The clamping mechanism 3 includes a first clamp 31 and a second clamp 32. The first clamp 31 and the second clamp 32 are two steel structures that are joined together. The sides of the first clamp 31 and the second clamp 32 are welded with reinforcing plates 33 and clamping plates 34. The first clamp 31 and the second clamp 32 are attached together by clamping plates 34 and fixed with bolts. A lifting ring 35 is rotatably provided at the outer edge of the top of the first clamp 31 and the second clamp 32. A lifting mechanism 36 is screwed to the inner wall of the lifting ring 35. A sponge 37 is provided on the top of the lifting mechanism 36. The sponge 37 is attached to the bottom of the pile cap body 1.

[0056] The lifting mechanism 36 includes a first support plate 361 and a second support plate 362. The first support plate 361 and the second support plate 362 are combined to form a ring structure. The bottom of the first support plate 361 and the second support plate 362 are welded with limit posts 363. The bottom end of the limit post 363 passes through the first hoop 31 and the second hoop 32 and slides with them. A slot 364 is provided at the splice of the second support plate 362. An insert block 365 is integrally provided at the splice of the first support plate 361. The insert block 365 is inserted into the inside of the slot 364.

[0057] The top of the first hoop 31 and the second hoop 32 is an outwardly extending annular platform. A groove is provided at the bottom of the annular platform near the outer edge. The lifting ring 35 slides in contact with the inner wall of the groove, and the lifting ring 35 consists of two hoop rings connected by bolts.

[0058] The load-bearing mechanism 6 includes an I-beam 61, which overlaps the top of the pile foundation structure 2. Two supports 62 are installed on the I-beam 61. The top of the supports 62 is connected in sequence to a sliding rod 64 and a screw block 65. A limit plate 63 slides on the surface of the sliding rod 64. The limit plate 63 is welded in the pile core cage 8. An inner screw cylinder 66 is screwed to the outer edge of the top of the screw block 65. A rotating rod 67 is integrally installed at the top of the inner screw cylinder 66. The top of the rotating rod 67 passes through the pile cap body 1 and is equipped with an adjusting cap 68.

[0059] The surface of the I-beam 61 is provided with a strip groove and a spiral groove, and the two supports 62 are respectively slidably connected to the inner wall of the strip groove and spirally connected to the inner wall of the spiral groove.

[0060] like Figure 1-5 As shown, the construction methods include:

[0061] Step S1: Begin driving the piles and process the pile foundation structure 2 and the pile core cage 8.

[0062] Step S2: Hoist the pile cap body 1 onto the top of the pile foundation structure 2 and perform leveling.

[0063] Step S3: Set the corresponding clamping mechanism 3 according to the inclination of the pile foundation structure 2, and press it onto the bottom of the pile cap body 1;

[0064] Step S4: Perform underwater grouting.

[0065] Step S1: Begin pile driving and process the pile foundation structure 2 and pile core cage 8, including:

[0066] Step S11: Perform pile driving operation according to design requirements;

[0067] Step S12: After pile driving, measure the pile position deviation, slope, torsion angle and elevation.

[0068] Step S13: For inclined piles, according to the designed elevation, the surveyor will cooperate to use an underwater chainsaw to cut the pile head to ensure it is flat.

[0069] Step S14: Process the core cage 8 so that its exposed part is arranged vertically.

[0070] Step S2 involves hoisting the pile cap body 1 onto the top of the pile foundation structure 2 and performing leveling treatment, including:

[0071] Step S21: Hoist the pile cap body 1 so that the hoisted pile cap body 1 is inserted into the pile foundation structure 2;

[0072] Step S22: The load-bearing mechanism 6 is attached to the top of the pile foundation structure 2 to support the pile cap body 1.

[0073] Step S23: After the pile cap body 1 is placed and stabilized, the load-bearing mechanism 6 is adjusted according to the specifications of the pile and the pile driving deviation and elevation to make the pile cap body 1 horizontal.

[0074] Step S3, setting the corresponding clamping mechanism 3 according to the inclination of the pile foundation structure 2, and pressing it onto the underside of the pile cap body 1, includes:

[0075] Step S31: Make the corresponding clamping mechanism 3 according to the slope of each pile;

[0076] Step S32: The two halves of the clamping mechanism 3 are bolted together and clamped onto the pile foundation structure 2;

[0077] Step S33: The top of the clamping mechanism 3 is attached tightly to the bottom of the pile cap body 1, and the clamping mechanism 3 is fixed to the pile foundation structure 2.

[0078] Step S4, underwater grouting construction includes:

[0079] Step S41: Using a guide tube, insert it from the grouting hole 5 to the bottom of the grouting space, leaving a 10cm gap for grouting;

[0080] Step S42: As grouting proceeds, the water outlet 4 gradually drains the water from the grouting space under the filling of grouting material. After the grouting material is gradually poured to the elevation of the water outlet 4, the water outlet 4 is plugged with a wooden plug.

[0081] Step S43: During the grouting process, ensure that the lower end of the guide pipe is always buried in the grout. As the grouting volume increases or decreases, gradually raise the guide pipe until the grouting space is completely filled, and then seal the grouting hole 5.

[0082] When constructing an underwater high-pile wharf, the deviation, slope, torsion angle, and elevation of the pile foundation structure 2 are first measured. Then, a clamping mechanism 3 with the corresponding inclination is produced. After adjusting the pile core cage 8 to a vertical state, the pile cap body 1 is suspended and installed on the pile foundation structure 2. The clamping mechanism 3 is then clamped onto the pile foundation structure 2 and attached to the bottom of the pile cap body 1. Concrete is then injected into the grouting space through the grouting hole 5 using a pipe. As the concrete increases, the water in the grouting space is discharged through the water outlet hole 4. After grouting is completed, the water outlet hole 4 and the grouting hole 5 are sealed with wooden plugs.

[0083] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A construction method for precast pile cap structures used in platform-free underwater construction, wherein the precast pile cap structures used in platform-free underwater construction include: The pile cap body (1) has a pile foundation structure (2) at its bottom. The pile cap body (1) is connected to the pile foundation structure (2) by concrete grouting. A clamping mechanism (3) is fitted onto the surface of the pile foundation structure (2) near its top. The top of the clamping mechanism (3) is attached to the pile cap body (1). The interior of the pile cap body (1) is integrally formed with a corrugated pipe (7) for grouting. Two grouting holes (5) are opened at the top of the pile cap body (1). The grouting hole (5) leads into the grouting space. The side of the pile cap body (1) is provided with a water outlet (4). The inner wall of the water outlet (4) penetrates the corrugated pipe (7) to connect the grouting space with the outside. The pile cap body (1) is provided with a load-bearing mechanism (6). The structure at the top of the load-bearing mechanism (6) penetrates the pile cap body (1) and is screwed to it. The structure at the bottom of the load-bearing mechanism (6) overlaps with the top of the pile foundation structure (2). The top of the pile foundation structure (2) is integrally provided with a pile core cage (8). The portion of the pile core cage (8) extending beyond the top of the pile foundation structure (2) is vertically inserted into the grouting space inside the pile cap body (1); The top of the clamping mechanism (3) is horizontally positioned, and the middle part of the clamping mechanism (3) is attached to the surface of the pile foundation structure (2). The load-bearing mechanism (6) includes an I-beam (61), which overlaps the top of the pile foundation structure (2). Two supports (62) are provided on the I-beam (61). A sliding rod (64) and a screw block (65) are connected to the top of the supports (62) in sequence. A limiting plate (63) slides on the surface of the sliding rod (64). The limiting plate (63) is welded in the pile core cage (8). An inner screw cylinder (66) is screwed to the outer edge of the top of the screw block (65). A rotating rod (67) is integrally provided at the top of the inner screw cylinder (66). The top of the rotating rod (67) penetrates the pile cap body (1) and is provided with an adjusting cap (68). Its characteristic is that the construction method includes: Step S1: Start driving the piles and process the pile foundation structure (2) and the pile core cage (8); Step S2: Hoist the pile cap body (1) onto the top of the pile foundation structure (2) and perform leveling treatment; Step S3: Set up the corresponding clamping mechanism (3) according to the inclination of the pile foundation structure (2) and press it under the pile cap body (1); Step S4: Perform underwater grouting.

2. The construction method for precast pile cap structures for platform-free underwater construction according to claim 1, characterized in that, Step S1, which involves starting pile driving and processing the pile foundation structure (2) and the pile core cage (8), includes: Step S11: Perform pile driving operation according to design requirements; Step S12: After pile driving, measure the pile position deviation, slope, torsion angle and elevation. Step S13: For inclined piles, according to the designed elevation, the surveyor will cooperate to use an underwater chainsaw to cut the pile head to ensure it is flat. Step S14: Process the core cage (8) so that its exposed part is arranged vertically.

3. The construction method for precast pile cap structures for platform-free underwater construction according to claim 1, characterized in that, Step S2, which involves hoisting the pile cap body (1) onto the top of the pile foundation structure (2) and performing leveling treatment, includes: Step S21, hoist the pile cap body (1) so that the hoisted pile cap body (1) is inserted into the pile foundation structure (2); Step S22: The load-bearing mechanism (6) is attached to the top of the pile foundation structure (2) to support the pile cap body (1); Step S23: After the pile cap body (1) is placed and stabilized, the load-bearing mechanism (6) is adjusted according to the specifications of the pile and the pile driving deviation and elevation so that the pile cap body (1) is set horizontally.

4. The construction method for precast pile cap structures for platform-free underwater construction according to claim 1, characterized in that, Step S3, which involves setting a corresponding clamping mechanism (3) according to the inclination of the pile foundation structure (2) and pressing it against the bottom of the pile cap body (1), includes: Step S31: Make the corresponding clamping mechanism according to the slope of each pile (3). Step S32, the two halves of the clamping mechanism (3) are bolted together and clamped onto the pile foundation structure (2); Step S33: Use the top of the clamping mechanism (3) to press against the bottom of the pile cap body (1), and fix the clamping mechanism (3) to the pile foundation structure (2).

5. The construction method for precast pile cap structures for platform-free underwater construction according to claim 1, characterized in that, Step S4, underwater grouting construction, includes: Step S41: Using a guide tube, insert it into the bottom of the grouting space from the grouting hole (5), leaving 10cm for grouting; Step S42: As grouting proceeds, the water outlet (4) gradually drains the water in the grouting space under the filling of grouting material. After the grouting material is gradually poured to the elevation of the water outlet (4), the water outlet (4) is plugged with a wooden plug. Step S43: During the grouting process, ensure that the lower end of the guide pipe is always buried in the grout. As the grouting volume increases or decreases, gradually raise the guide pipe until the grouting space is completely filled, and seal the grouting hole (5).

6. The construction method for a precast pile cap structure for platform-free underwater construction according to claim 1, characterized in that, The clamping mechanism (3) includes a first clamp (31) and a second clamp (32). The first clamp (31) and the second clamp (32) are two steel structures that are joined together. The sides of the first clamp (31) and the second clamp (32) are welded with reinforcing plates (33) and clamping plates (34). The first clamp (31) and the second clamp (32) are attached together by clamping plates (34) and fixed with bolts. A lifting ring (35) is rotatably provided at the outer edge of the top of the first clamp (31) and the second clamp (32). A lifting mechanism (36) is screwed to the inner wall of the lifting ring (35). A sponge (37) is provided on the top of the lifting mechanism (36). The sponge (37) is attached to the bottom of the pile cap body (1).

7. The construction method for precast pile cap structures for platform-free underwater construction according to claim 6, characterized in that, The lifting mechanism (36) includes a first support plate (361) and a second support plate (362). The first support plate (361) and the second support plate (362) are combined to form a ring structure. The bottom of the first support plate (361) and the second support plate (362) are welded with a limiting post (363). The bottom end of the limiting post (363) passes through the first hoop (31) and the second hoop (32) and slides with them. The splice of the second support plate (362) is provided with a slot (364). The splice of the first support plate (361) is integrally provided with an insert (365). The insert (365) is inserted into the inside of the slot (364).

8. The construction method for precast pile cap structures for platform-free underwater construction according to claim 6, characterized in that, The top of the first hoop (31) and the second hoop (32) is an outwardly extending annular platform. A groove is provided at the bottom of the annular platform near the outer edge. The control ring (35) slides in contact with the inner wall of the groove. The control ring (35) consists of two hoop rings connected together by bolts.

9. The construction method for a precast pile cap structure for platform-free underwater construction according to claim 1, characterized in that, The surface of the I-beam (61) is provided with a strip groove and a spiral groove, and the two supports (62) are respectively slidably connected to the inner wall of the strip groove and spun to the inner wall of the spiral groove.

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