Underwater combined steel pipe pile cutting process

Abstract

The application discloses a cutting process for underwater combined steel pipe piles, which comprises the following steps: embedding foundation bolts for fixing a cutting assembly on a bottom plate in front of a dock opening; fixing an operating platform and a pile body adjacent to a combined steel pipe pile to be cut by using fasteners to form an integrated structure; laying an assembly part between the combined steel pipe pile to be cut and an adjacent steel pipe pile through the foundation bolts; laying a diamond wire saw on the assembly part along a guide assembly; when laying the diamond wire saw, the diamond wire saw is laid in a direction of first vertical and then horizontal, and the diamond wire saw forms a fastening ring for fixing the combined steel pipe pile to be cut in the horizontal direction; the diamond wire saw is directed towards the operating platform through a turning assembly along both sides of the fastening ring to form a cutting path; and the cutting part is controlled to cut along a cutting surface in a mode of first horizontal cutting and then vertical adjustment. The application realizes the cutting of the combined pile through the guide assembly.

Description

Technical Field

[0001] This invention belongs to the field of underwater composite steel pipe pile cutting technology, specifically relating to an underwater composite steel pipe pile cutting process. Background Technology

[0002] The combined steel pipe piles and cast-in-place piles on axis F at the dock entrance are the retaining pile system to be cut. The retaining pile system uses steel pipe piles (φ1219@1470mm), and the bottom of the pile body is anchored by rock-socketed cast-in-place piles. On the sea side of the combined steel pipe piles, high-pressure jet grouting piles (φ900@600mm) and bedrock construction water-stop curtain together with the retaining piles form a water-stopping system. Since the cutting elevation of the retaining piles is -14.0m, the retaining pile combination system cut by wire saw at this elevation needs to simultaneously cut steel pipe piles, cast-in-place piles, high-pressure jet grouting piles, and sea mud attached to the body, which are composed of different materials.

[0003] In existing technologies, underwater operations are carried out by divers fixing the piles one by one and observing them at any time during the cutting process. Since divers are a specialized profession, the operation time is long, the cost is high, and the safety risks are also great. Summary of the Invention

[0004] Based on the above analysis, this invention proposes an underwater composite steel pipe pile cutting process, which solves the problems of long working hours for divers, the need for real-time monitoring, and high construction costs in the prior art.

[0005] To achieve the above effects, the present invention is implemented through the following technical solution.

[0006] A cutting process for underwater composite steel pipe piles includes the following steps:

[0007] Anchor bolts for fixing the cutting components are pre-embedded on the bottom plate at the front edge of the dock.

[0008] Fasteners are used to fix the operating platform and the adjacent piles of the combined steel pipe piles to be cut into an integrated structure.

[0009] Using the anchor bolts, an assembly part is laid on the guide component at the bottom of the operating platform between the combined steel pipe pile to be cut and the adjacent steel pipe pile;

[0010] A diamond wire saw is laid along the guide assembly on the assembly section;

[0011] When laying diamond wire saws, they are laid in a direction that is first vertical and then horizontal. Along the horizontal direction, the diamond wire saws form a fastening ring to fix the steel pipe pile to be cut. Along both sides of the fastening ring, the diamond wire saws are oriented toward the operating platform through the steering component to form a cutting path.

[0012] Control the cutting part and cut along the cutting surface by first cutting horizontally and then adjusting vertically.

[0013] In this technical solution, a diamond wire saw is used to form a fastening ring. When divers are working, they only need to ensure a stable connection at the bottom, and then the upper part can be directly fixed with multiple combination piles. This allows for the simultaneous cutting of multiple combination piles during the later cutting process, so that multiple cuts can be made with only one fixing.

[0014] In this technical solution, the operating platform is fixed based on adjacent steel pipe piles. During the cutting process, the operating platforms are close together and have good stability. Especially for the cutting of longer steel pipe piles, it is necessary to fully consider the overall assembly stability of the operating platform as the cutting progresses. This technical solution overcomes the above problems.

[0015] In this technical solution, by fixing the operating platform and adjacent steel pipe piles as a whole, a stable support assembly is formed. In the height direction, it has a certain restraint, which improves stability. The addition of guiding components and assembly parts makes the entire diamond wire saw assembly more robust.

[0016] As a further improvement of the present invention, the method of fixing the operating platform and the adjacent pile body of the combined steel pipe pile to be cut using fasteners is as follows: the limiting frame formed by the guide components at the bottom of the operating platform is sleeved on the adjacent steel pipe pile of the combined steel pipe pile to be cut, and the two are fixedly welded using underwater welding technology.

[0017] In this technical solution, the forming of the limiting frame is equivalent to enclosing the adjacent steel pipe piles, achieving all-round fixation, etc., so that divers can also carry out underwater construction operations when they go into the water. Compared with the previous multiple welding, the present invention only requires welding the limiting frame, and the working time is short.

[0018] As a further improvement of the present invention, it also includes the assembly of the operating platform with the adjacent pile body. Specifically, at the bottom of the operating platform, the distance between the operating platform and the adjacent pile body of the steel pipe pile to be cut is adjusted, and the operating platform is fixed at a set height by means of a buckle.

[0019] In this invention, due to processes such as tides, the entire cutting assembly is easily eroded by tides, affecting the construction progress. Therefore, it is necessary to increase the length of the bottom support connecting pipe by using clips to raise the operating platform and avoid contact with water.

[0020] In this technical solution, the platform guide wheels and brackets are specifically fixed to the adjacent pile bodies of the assembled steel pipe piles to be cut using an underwater welding process.

[0021] As a further improvement of the present invention, it also includes the setting of cutting auxiliary lines, specifically: opening a hole along the locking position of the combined steel pipe pile to be cut, and chiseling the hole to the position to be cut, and setting a cutting auxiliary line in the chiseled hole from the opening to the position to be cut.

[0022] In this technical solution, a hole is made at the locking position of the combined pile, and the hole is chiseled to the position to be cut. A cutting auxiliary line is set in the chiseled hole from the opening to the position to be cut to ensure the stability of the pipe pile in the height direction.

[0023] As a further improvement of the present invention, the guiding component includes a first guide wheel and a second guide wheel located below the first guide wheel. The first guide wheel forms a first guide trajectory from vertical to horizontal in the direction from the second guide wheel, and the second guide wheel forms a second guide trajectory from horizontal to vertical in the direction from the first guide wheel.

[0024] In this technical solution, the guide component simultaneously achieves multiple functions, such as horizontal to vertical or vertical to horizontal, and can thus be used in multiple locations. Specifically, in this technical solution, the guide component includes a vertical wheel and two horizontal wheels, with a guide gap formed between the horizontal wheels to guide the wheel to the vertical wheel.

[0025] As a further improvement of the present invention, along the cutting surface, the guide assembly consists of at least two sets, located on both sides of the steel pipe composite pile to be cut.

[0026] In this technical solution, two guide wheel sets are added, which have a certain clamping function, making the two sides of the composite pile to be cut more stable. As the cutting degree of the diamond wire saw is adjusted, the length and tension of the diamond wire saw are adjusted simultaneously along the two guide wheel sets, resulting in good symmetry and stable cutting.

[0027] As a further improvement of the present invention, when laying diamond wire saws, starting from the operating platform, the saw is first laid vertically along the direction of the second guide track of the guide component, and after passing the assembly part, it is laid horizontally along the direction of the second guide track of the guide component.

[0028] In this technical solution, the cutting trajectory on the operating platform is set from horizontal to vertical and then back to horizontal. The two horizontal directions form a cutting height, and the vertical direction ensures the stability of the height, which is more efficient. At the same time, a single guide component can realize different guide paths, which is cost-effective.

[0029] As a further improvement of the present invention, there are several assembly parts, and along the height direction, the diamond wire saw is staggered along the assembly parts and covers the guide component.

[0030] In this technical solution, stability in the height direction is fully considered, and the misalignment setting makes the diamond wire saw inevitably form a winding structure, especially the S-shaped misalignment, which then winds around the adjacent steel pipe pile or the guide component, thus improving the overall stability.

[0031] As a further improvement of the present invention, the height difference between adjacent assembly parts along the height direction is less than or equal to 4m.

[0032] In this technical solution, in order to fully consider stability, the height difference of the assembly part is not less than 4m, that is, the turning will occur within 4m, so that the diamond wire saw has a certain winding in the horizontal direction. When the diamond wire saw is under force, it will not be deflected to other positions and cause safety risks.

[0033] As a further improvement of the present invention, the composite steel pipe pile to be cut includes a steel pipe pile, a rock-socketed cast-in-place pile inside the steel pipe pile, a cast-in-place pile on the sea side closely attached to the steel pipe pile, and a high-pressure jet grouting pile. The steel pipe pile, the cast-in-place pile, and the high-pressure jet grouting pile form a triangular interface. During cutting, the high-pressure jet grouting pile is cut first, followed by the steel pipe pile and / or the cast-in-place pile.

[0034] In this technical solution, due to the strong force of the diamond wire saw, the outermost high-pressure jet grouting pile can be cut first among multiple steel pipe piles. Then, as the horizontal direction is adjusted, the steel pipe piles will be cut simultaneously when the cast-in-place piles are cut to a certain extent. Furthermore, as the position of the combined piles is adjusted, there may be simultaneous cutting or cutting without distinguishing the order. Attached Figure Description

[0035] Figure 1 A flowchart of an underwater composite steel pipe pile cutting process provided by the present invention;

[0036] Figure 2 The flowchart illustrates the application of an underwater composite steel pipe pile cutting process provided by this invention. Detailed Implementation

[0037] The structure and working principle of the present invention will be further described in detail below with reference to the accompanying drawings.

[0038] To make the objectives and technical solutions of this invention clearer and easier to understand, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0039] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more. In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0040] The underwater composite steel pipe pile cutting process in this embodiment is as follows:

[0041] A cutting process for underwater composite steel pipe piles includes the following steps:

[0042] Anchor bolts for fixing the cutting components are pre-embedded on the bottom plate at the front edge of the dock.

[0043] Fasteners are used to fix the operating platform and the adjacent piles of the combined steel pipe piles to be cut into an integrated structure.

[0044] Using the anchor bolts, an assembly part is laid on the guide component at the bottom of the operating platform between the combined steel pipe pile to be cut and the adjacent steel pipe pile;

[0045] A diamond wire saw is laid along the guide assembly on the assembly section;

[0046] When laying diamond wire saws, they are laid in a direction that is first vertical and then horizontal. Along the horizontal direction, the diamond wire saws form a fastening ring to fix the steel pipe pile to be cut. Along both sides of the fastening ring, the diamond wire saws are oriented toward the operating platform through the steering component to form a cutting path.

[0047] Control the cutting part and cut along the cutting surface by first cutting horizontally and then adjusting vertically.

[0048] In this invention, the anchor bolts are pre-embedded in the bottom plate at the front edge of the dock before the water is released, according to the cutting arrangement.

[0049] To achieve more stable cutting, fasteners are used to fix the operating platform and the adjacent piles of the combined steel pipe piles to be cut. Specifically, a limiting frame, composed of guide components at the bottom of the operating platform, is fitted onto the adjacent steel pipe piles of the combined steel pipe piles to be cut, and underwater welding is used to achieve a fixed weld between the two. Compared to simple welding, the limiting frame of this invention directly achieves a fixed fit, resulting in a more stable connection.

[0050] In this invention, in order to reduce the underwater operations of divers, the steel pipe pile to be cut is a composite pile. At the bottom of the operating platform, the distance between the operating platform and the adjacent piles of the composite steel pipe pile to be cut is adjusted, and the operating platform is fixed at a set height using a snap-fit ​​method.

[0051] Drill holes along the locking position of the composite pile and chisel the holes to the position to be cut, and set cutting auxiliary lines in the chisel holes from the opening to the position to be cut.

[0052] During horizontal cutting, the cutting component is a diamond wire saw, which is set along the horizontal plane. The diamond wire saw connects the assembly parts formed by adjacent guide wheels to form a closed cavity.

[0053] Because the distance between the pile and the cutting assembly is relatively large, in order to ensure vertical stability, the spacing between the guide wheels along the height direction of the steel pipe pile to be cut must not exceed 4m. In this embodiment, the vertical spacing between the guide wheels is set between 4m and 5m and should not be too large to ensure the smoothness of the wire saw cutting.

[0054] To achieve reversal, the reversing component in this invention specifically consists of a vertical pulley and two horizontally placed pulleys. The central axes of the vertical pulley of the steering wheel and the vertical guide wheel need to be on the same cross section (i.e., the Y-section). While ensuring the reversal, adjustments can be made left and right in the X-section direction as needed to make the wire saw S-shaped in the vertical plane, reducing the swing amplitude of the wire saw. The centers of the two horizontally placed pulleys and the center of the vertical pulley are on a straight line, and the distance between them must not be greater than the diameter of the diamond wire saw, nor should they contact each other to avoid generating resistance that affects the cutting efficiency.

[0055] When the cutting process of this invention is applied to the demolition of combined steel pipe piles in a dry dock, the specific details are as follows:

[0056] Project Introduction

[0057] Because the dock was built within an old shipyard, and due to the influence of surrounding concrete structures and existing underground pipelines, the dock construction could only be carried out by using retaining structures for support before excavation, and large-slope excavation was not permitted. The deep foundation pit at the dock entrance on the sea side uses composite steel pipe piles (φ1219@1470mm), with rock-socketed cast-in-place piles anchored at the bottom of the piles. Drilled rock-socketed cast-in-place piles (φ1200mm@1400mm) are used as retaining piles on both sides of the pit and the shore side. Behind the retaining piles, high-pressure jet grouting piles (φ900@600mm) and a bedrock-constructed water-stop curtain, together with the retaining piles, form a water-stopping system.

[0058] During the cutting process, the analysis showed that the assembly and maintenance unit to be disassembled was located at the dock entrance. A pump room and a north wing wall were located on the left side of the dock entrance, and a south wing wall was located on the right side of the dock entrance.

[0059] The main construction process is shown in the appendix. Figure 2 As shown, it specifically includes the following:

[0060] The bottom plate structure at the front edge of the dock is completed, and the wire cutting equipment is pre-embedded in the bottom plate at the front edge. Wire cutting holes are opened at the locking points of the combined steel pipe piles.

[0061] The dock structure is complete, and the revetment has been dismantled.

[0062] The dock was drained, and the combined steel pipe piles were dredged on the seaside to the designed seabed elevation.

[0063] The cutting equipment was installed and in place, and the combined steel pipe piles and cast-in-place piles were cut horizontally in sections.

[0064] In this embodiment, the preparatory work before the cutting process is as follows:

[0065] After the dock front edge bottom plate is completed, preparations for the dismantling of the combined steel pipe piles begin. This includes: pre-embedding anchor bolts for fixing the wire cutting equipment on the dock front edge bottom plate; drilling holes at the cutting elevation on the joint of the combined steel pipe piles; placing reinforcing bars in the wire cutting holes to facilitate the threading of the cutting wire; cleaning the soil and other filling materials inside the steel pipe piles; and installing the wire cutting operation platform on the top of the combined steel pipe piles.

[0066] Before the water is released, an underwater cutting specialist will pre-install anchor bolts for the guide wheels on the bottom plate of the dock chamber according to the cutting layout, thereby reducing the amount of underwater work and speeding up the construction progress.

[0067] During the construction of the civil structure, clay was used for backfilling to prevent personnel and equipment from falling into the steel pipe piles. To prevent the soil from obscuring the divers' vision when cutting and lifting, to prevent accidents caused by falling during the lifting process, and to increase the weight of the composite piles, the soil inside the composite piles was cleaned by water flushing before demolition.

[0068] The application of jet grouting for seepage prevention on the seaside of the composite piles increased the difficulty of installing the underwater wire cutting equipment. Before releasing water, holes were drilled at the interlocking position of the composite pile along the cutting elevation, extending beyond the range of the jet grouting pile body. A steel bar was then inserted to assist in threading and cutting the wire. This minimized underwater operations by divers and improved efficiency.

[0069] Cutting of composite steel pipe piles

[0070] After the dredging vessel cleared the seaside of the composite steel pipe piles to the design elevation, a wire cutting operation platform was installed on the adjacent piles to be cut. Divers descended in groups, installed the wire cutting steering pulleys, and used pre-embedded wire cutting perforated steel bars to install the cutting line. Horizontal cutting of the composite steel pipe piles at the design elevation began. The horizontal cutting was performed on a group basis, consisting of one composite steel pipe pile, one rock-socketed cast-in-place pile, a cast-in-place pile adjacent to the outer side of the steel pipe pile, and a high-pressure jet grouting pile. After circumferential cutting, vertical cutting was performed along both sides of the unit to be demolished until the unit was completely detached from the surrounding structure. During vertical cutting, a crane vessel was positioned to suspend the steel pipe composite pile unit to be demolished, preventing it from suddenly collapsing and injuring divers and operators.

[0071] Divers descend in groups to install the wire cutter steering pulley (i.e., steering assembly), and use pre-embedded wire cutter perforated steel bars to install the cutting line in place, beginning the horizontal cutting of the assembled steel pipe pile at the designed elevation. As the cutting process progresses, the wire saw gradually shortens. During cutting, the equipment operator continuously monitors the tension of the wire saw to prevent it from becoming too loose, which could cause excessive fluctuations and jamming.

[0072] After the circumferential cutting is completed, vertical cuts are made along both sides of the unit to be demolished until the unit to be demolished is completely separated from the surrounding structure.

[0073] The key points of construction in this invention are as follows:

[0074] When installing a cutting and reversing device underwater, the pre-embedded bolts of the cutting and reversing device must be correctly installed before waterproofing. Positioning and drilling are required for pre-embedding, and it must be ensured that the bolts are securely fixed.

[0075] The cutting line is drilled before the water is released. A steel bar is placed underwater in an easily accessible location as a guide. The cutting and drilling range extends from the shore to the steel pipe pile interlocking lock and the outer high-pressure jet spray body on the sea side.

[0076] Before vertically cutting between each lifting unit, ensure that the weight is within the lifting capacity of the crane vessel.

[0077] The underwater combined steel pipe pile cutting process of this invention mainly includes: underwater preparation work → installation of the working platform connecting sleeve → installation of the platform guide frame (i.e., guide component) → installation of the wire saw vertical guide wheel (i.e., assembly part) → installation of the wire saw steering wheel (vertical to horizontal, i.e., steering component) → installation of the diamond wire saw → underwater welding and reinforcement of the guide frame → equipment debugging → start cutting.

[0078] In this invention, the cutting components are set on the operating platform. The operating platform is first assembled on the shore with conventional components and vertical guide wheels, and then fixed on the combined steel pipe pile. The steering wheel is then adjusted and welded underwater according to the cutting angle to complete the assembly of the operating platform.

[0079] The cutting work of this invention is limited mainly by the characteristics of the composite pile body, including composite steel pipe piles containing rock-embedded cast-in-place piles, cast-in-place piles that are closely attached to steel pipe piles in marine surveying, and high-pressure jet grouting piles attached to the pile body. Various pile types are tightly attached, making it impossible to cut them individually.

[0080] This invention utilizes the interlocking mechanism of combined steel pipe piles to form a single unit. Simultaneously, through conventional underwater welding, the operating platform and adjacent steel pipe piles to be cut are integrated to prevent platform swaying during cutting, which could cause the wire saw to jam.

[0081] In this invention, the cutting process also includes the following steps:

[0082] 1) Due to the large difference between the cutting elevation and the cutting equipment, the length of the wire saw underwater reaches 40m-50m. During the cutting process, the wire saw will swing significantly due to the fluctuation of seawater and the length of the wire saw. To reduce the swing amplitude, the vertical guide wheel spacing is set between 4m-5m and should not be too large to ensure the smoothness of the wire saw cutting.

[0083] In this invention, a vertical guide wheel forms the assembly unit, guiding the diamond wire saw vertically to the seabed cutting elevation. A steering assembly consisting of steering wheels then converts the wire saw to a horizontal orientation. After the diamond wire saw wraps around the composite pile body to be cut, the steering assembly again uses steering wheels to convert the horizontal wire saw to a vertical orientation, and then the vertical guide wheel leads it out to sea level and connects it to the equipment. This cutting process simultaneously cuts composite steel pipe piles, cast-in-place piles, and high-pressure jet grouting piles, greatly improving cutting efficiency.

[0084] 2) To prevent the diamond wire saw from accidentally cutting the guide wheel or steering wheel during cutting, the center lines of the vertical guide wheel and steering wheel need to be installed on the same cross-section (Y-section) according to the direction of the diamond wire saw. Simultaneously, to improve the contact force between the diamond wire saw and the vertical guide wheel, while ensuring the installation center of the vertical guide wheel is on the Y-section, adjustments can be made left or right in the X-section direction as needed. This allows the wire saw to be set in an S-shape under the action of the vertical assembly, reducing the swing amplitude of the wire saw and thus ensuring the integrity of the guide wheel and steering wheel.

[0085] In this invention, in the steering assembly, the centers of the two horizontally placed pulleys and the center of the vertical pulley are on a straight line, and the distance between them must not be greater than the diameter of the diamond wire saw, nor can they contact each other, so as to avoid generating resistance that affects the cutting efficiency.

[0086] 3) To control the cutting elevation, divers manually chisel out a groove 10cm-20cm long and 3cm-5cm deep at the contact point between the diamond wire saw and the pile to be cut. This prevents the wire saw from swinging up and down due to insufficient friction on the contact surface when the equipment starts cutting, which would cause the cutting elevation to not meet the requirements.

[0087] 4) After the wire cutting platform and wire saw are installed, the divers will weld and reinforce the steering wheel and platform guide frame to prevent the wire saw from getting stuck due to platform shaking during cutting.

[0088] 5) During the operation of the cutting equipment, the required length of the underwater wire saw will gradually decrease. The operator must pay attention to the tension of the wire saw at all times to prevent it from falling out of the pulley groove due to being too loose, or from getting stuck due to being too tight.

[0089] 6) The design cutting elevation must be at least 0.5m higher than the seabed elevation. This is to provide underwater working space for divers and improve work efficiency. On the other hand, if the seabed elevation is close to the cutting elevation, when the wire saw is running, the seawater will flow rapidly with the high speed of the wire saw, and the sand and gravel on the seabed will enter the cutting seam, affecting the smoothness of the cutting.

[0090] The cutting process described in this invention can simultaneously cut one steel pipe pile, one cast-in-place pile, and an adjacent high-pressure jet grouting pile within 2.5 days, greatly improving construction efficiency. Furthermore, compared to other traditional processes, this technology significantly reduces safety risks, and the cutting process is unaffected by factors such as the material, shape, and seawater conditions of the structure, thus lowering construction costs and achieving the goal of cost reduction and efficiency improvement. It provides decision-making insights and reference value for similar projects or demolition in complex underwater environments, and has the potential for widespread application.

[0091] In this invention, an underwater combined steel pipe pile wire saw cutting system is selected for cutting, consisting of a wire cutting platform, a diamond wire saw, wire saw cutting equipment, and other auxiliary tools. The wire cutting platform consists of an operator's work platform (including safety railings), a platform connecting sleeve, a platform guide frame, vertical guide wheels for the wire saw, and a wire saw steering wheel (vertical to horizontal).

[0092] Using the connecting sleeve of the wire cutting platform, the platform is placed inside the steel pipe pile adjacent to the pile to be cut. The elevation of the operating platform must be higher than the highest tide level to prevent the equipment from being affected by rising seawater. The diver uses the vertical guide wheels installed on the platform's guide frame to pull the diamond wire saw to the cutting elevation, and then uses the steering wheels to turn the wire saw from the vertical direction to the horizontal direction before winding it around the pile to be cut. After connecting it to the cutting equipment and completing the debugging, the operator can begin safe cutting on the platform after the diver leaves the construction area.

[0093] After the combined steel pipe piles, cast-in-place piles and high-pressure jet grouting piles to be dismantled were cut, the divers removed the wire saw and the auxiliary support for fixing the guide wheels. After the crane boat was used to transfer the entire operating platform to the subsequent construction position, the cut combined steel pipe piles and cast-in-place piles were lifted out by crane.

[0094] This invention has the following advantages:

[0095] 1) Low safety risk: The underwater installation and commissioning of the underwater combined steel pipe pile wire saw cutting system are all completed by divers according to conventional underwater operation requirements. During the initial and final stages of equipment operation, divers do not need to supervise or operate underwater. In addition, the operating platform is installed inside the steel pipe pile adjacent to the pile to be cut, and the cutting ends at the locking point of the combined steel pipe pile, without cutting into the platform pile body, thus ensuring the safety of the operators.

[0096] 2) Optimization of Special Operations Personnel Configuration: The underwater work performed by divers includes installing the work platform, installing the wire saw, debugging the equipment, and welding and reinforcing the guide frame and guide wheels. This reduces the workload and difficulty of the diving work. While the wire saw is cutting normally, divers can be assigned to other tasks according to needs and international diving standards, thus optimizing the diver personnel configuration.

[0097] 3) High cutting efficiency: Due to the special nature of the pile structure and pile location design, it is impossible to use a wire saw to cut cast-in-place piles and steel pipe piles separately. If manual chiseling of cast-in-place piles, high-pressure jet grouting piles, and underwater cutting of steel pipe columns are used, a large number of divers are required to complete the task. In contrast, this technology can cut combined steel pipe piles and cast-in-place piles simultaneously underwater, achieving a cutting efficiency of "1+1+1<3", which greatly saves construction time.

[0098] The beneficial effects of this invention are as follows:

[0099] In this invention, an underwater installation cutting and reversing device is provided. Before the waterproof dock is flooded, the pre-embedded bolts of the cutting and reversing device need to be correctly installed. Positioning and drilling are required for pre-embedding, and it must be ensured that the bolts are securely fixed.

[0100] This invention reduces the difficulty of installing the wire cutting equipment underwater. Before releasing water, a hole is drilled at the locking position of the combined steel pipe pile along the cutting elevation, and the hole is chiseled to outside the range of the jet grouting pile body. A reinforcing bar is then inserted to assist in threading and cutting the wire. This minimizes underwater operations for divers and improves efficiency.

[0101] The above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art can still make modifications or equivalent substitutions to the specific implementation schemes of the present invention, and these modifications or equivalent substitutions do not depart from the spirit and scope of the present invention, and are all within the protection scope of the claims of the present invention.

Claims

1. A cutting process for underwater composite steel pipe piles, characterized in that, Includes the following steps: Anchor bolts for fixing the cutting components are pre-embedded on the bottom plate at the front edge of the dock. Fasteners are used to fix the operating platform and the adjacent steel pipe piles to be cut and assembled into an integrated structure. Using the anchor bolts, an assembly part is laid on the guide component at the bottom of the operating platform between the combined steel pipe pile to be cut and the adjacent steel pipe pile; A diamond wire saw is laid along the guide assembly on the assembly section; When laying diamond wire saws, they are laid in a direction that is first vertical and then horizontal. Along the horizontal direction, the diamond wire saws form a fastening ring to fix the steel pipe pile to be cut. Along both sides of the fastening ring, the diamond wire saws are oriented toward the operating platform through the steering component to form a cutting path. Control the cutting part and cut it along the cutting surface by first cutting horizontally and then adjusting it vertically; During horizontal cutting, the cutting component is a diamond wire saw, which is set along the horizontal plane. The diamond wire saw connects the assembly parts formed by adjacent guide wheels to form a closed cavity. Along the height direction of the steel pipe pile to be cut, the spacing between the guide wheels shall not exceed 4m; After the circumferential cutting is completed, vertical cuts are made along both sides of the unit to be demolished until the unit to be demolished is completely separated from the surrounding structure.

2. The underwater composite steel pipe pile cutting process according to claim 1, characterized in that, The method of fixing the operating platform and the adjacent piles of the combined steel pipe pile to be cut using fasteners is as follows: the limiting frame formed by the guide components at the bottom of the operating platform is fitted onto the adjacent steel pipe pile of the combined steel pipe pile to be cut, and the two are fixedly welded using underwater welding technology.

3. The underwater composite steel pipe pile cutting process according to claim 2, characterized in that, It also includes the assembly of the operating platform with the adjacent piles. Specifically, at the bottom of the operating platform, the distance between the operating platform and the adjacent steel pipe piles to be cut and assembled is adjusted, and the operating platform is fixed at the set height using a snap-fit ​​method.

4. The underwater composite steel pipe pile cutting process according to claim 1, characterized in that, It also includes the setting of cutting auxiliary lines, specifically: drilling a hole along the lock position of the combined steel pipe pile to be cut, and chiseling the hole to the position to be cut, and setting a cutting auxiliary line in the chiseled hole from the opening to the position to be cut.

5. The underwater composite steel pipe pile cutting process according to claim 1, characterized in that, The steering assembly includes a first guide wheel and a second guide wheel located below the first guide wheel. The first guide wheel forms a first guide trajectory from vertical to horizontal in the direction from the second guide wheel, and the second guide wheel forms a second guide trajectory from horizontal to vertical in the direction from the first guide wheel.

6. The underwater composite steel pipe pile cutting process according to claim 1, characterized in that, Along the cutting surface, the steering assembly consists of at least two sets, located on both sides of the steel pipe composite pile to be cut.

7. The underwater composite steel pipe pile cutting process according to claim 5, characterized in that, When laying diamond wire saws, start from the operating platform, first lay them vertically along the direction of the second guide track of the steering assembly, then lay them horizontally along the direction of the first guide track of the steering assembly after passing the assembly section.

8. The underwater composite steel pipe pile cutting process according to claim 1, characterized in that, The assembly part consists of several parts, and along the height direction, the diamond wire saw is arranged in a staggered manner along the assembly part, covering the guide component.

9. The underwater composite steel pipe pile cutting process according to claim 1, characterized in that, The composite steel pipe pile to be cut includes a steel pipe pile, a rock-embedded cast-in-place pile inside the steel pipe pile, a cast-in-place pile on the sea side closely attached to the steel pipe pile, and a high-pressure jet grouting pile. The steel pipe pile, cast-in-place pile, and high-pressure jet grouting pile form a triangular interface. During cutting, the high-pressure jet grouting pile is cut first, followed by the steel pipe pile and / or the cast-in-place pile.

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