Hoisting and transporting installation method of large box culvert hoisting device

Abstract

The application relates to a hoisting and transporting installation method of a large box culvert hoisting device, and relates to the technical field of large box culvert prefabrication, transporting and installation, in particular to a hoisting and transporting installation method of a large box culvert hoisting device for land prefabrication and water installation. The box culvert body is provided with two symmetrical through holes on the bottom plate, and the lower lifting cable is fixed on the hoisting frame after penetrating through the through holes; the through holes are located between the two layers of steel mesh sheets on the bottom plate of the box culvert body, the center of the through holes is horizontally arranged at a distance of one fourth of the length of the box culvert body from the two ends of the box culvert body, the two ends of the through holes are semicircular, and the through holes are reserved with the thickness of the steel reinforcement protective layer; the upper lifting cable is arranged at the top of the four corners of the hoisting frame. The application has the advantages of facilitating the hoisting of the large box culvert, not needing the assistance of divers under water, being capable of prefabricating double-layer or multi-layer box culverts, being simple in operation, being convenient to use, improving the construction efficiency and saving the construction cost.

Description

Technical Field

[0001] This invention relates to the field of prefabrication, transportation and installation technology of large box culverts, and in particular to a method for lifting, transporting and installing a large box culvert hoisting device that is prefabricated on land and installed on water. Background Technology

[0002] After the prefabrication of large box culverts, they need to be hoisted to the construction site's water area for installation. The box culvert transportation and installation process is generally on the critical path of the overall project schedule. Using conventional methods, this process takes 5-7 hours and requires waiting for high tide. Underwater assistance from divers is needed during installation, and specific shoreline structures are required for transportation. Therefore, this process often becomes a bottleneck restricting the overall project schedule. Currently, there are three methods for transporting and installing large prefabricated box culverts both domestically and internationally: the crane vessel lifting method, the airbag floating method, and a combined lifting and floating method. These three methods are mature technologies and have made significant contributions to the field of hydraulic engineering construction both domestically and internationally. However, in actual construction, the drawbacks of these methods, such as low installation efficiency, high construction costs, and significant safety hazards, have also become apparent.

[0003] The crane vessel top-mounted method involves embedding lifting rings on the top of the box culvert. Due to the significant weight of large box culverts (up to 460 tons per unit), the diameter of the round steel for the prefabricated lifting rings needs to be at least 12cm. Furthermore, the fabrication, installation, and reinforcement of the lifting rings are complex. Insufficient embedding depth necessitates additional reinforcement measures such as welding the hook to the reinforcing bars, welding steel plates to the ends, and installing mesh reinforcement and stirrups above the hook. Moreover, it requires diver assistance for installation and underwater hook removal, which is slow and dangerous. After installation, the lifting rings are exposed to seawater, making them susceptible to corrosion and reducing the durability of the box culvert concrete.

[0004] The combined airbag floating method and the ceiling floating method require the construction of a dedicated ramp or a vertical bank, which is custom-designed for construction and expensive. When using the ramp for transport, it needs to be moved into the water at the lowest tide and can only be floated and towed at high tide, resulting in low efficiency. During installation, the airbag is deflated and sits on the bottom, making the position difficult to control. In addition, it still requires the assistance of divers, resulting in low efficiency, poor accuracy and high danger.

[0005] Therefore, it is necessary to develop an advanced and convenient method for lifting, transporting, and installing large box culverts, so as to open up a new path for lifting, transporting, and installing large box culverts. Summary of the Invention

[0006] The purpose of this invention is to provide a method for lifting, transporting, and installing a large box culvert hoisting device, so as to facilitate the hoisting of large box culverts, eliminate the need for underwater measurement and positioning by divers and for unhooking operations, enable the prefabrication of double or multi-layer box culverts, simplify operation, facilitate use, improve construction efficiency, and save construction costs.

[0007] The large box culvert hoisting device provided by this invention includes a box culvert body and upper hoisting cables. The bottom plate of the box culvert body is provided with two symmetrical through holes. The lower hoisting cable passes through the through holes and is fixed to the hoisting frame. The through holes are located between two layers of steel mesh on the bottom plate of the box culvert body. The horizontal distance between the center of the through hole and the two ends of the box culvert body is one-quarter of the length of the box culvert body. The two ends of the through hole are semi-circular. The through hole is 50mm away from the steel reinforcement of the bottom plate of the box culvert body. The dimensions of the through hole are 750mm in length and 140mm in height, which is to allow for the thickness of the steel reinforcement protective layer. Upper hoisting cables are provided at the top of the four corners of the hoisting frame.

[0008] Furthermore, the hoisting frame has two pairs of coarse positioning markers at its four corners, and precise positioning markers at its front and rear ends. The bottom of the hoisting frame has a double-locking shackle for releasing hooks. A total station prism or GPS receiver is installed on the top of the precise positioning markers. A lower sling is installed on the double-locking shackle for releasing hooks.

[0009] Furthermore, a reinforcing rod is provided in the middle of the hoisting frame, and support rods are provided at the four corners of the hoisting frame and on both sides of the reinforcing rod; a precision positioning marker is provided at the front end and rear end of the reinforcing rod.

[0010] Furthermore, the construction of the through-hole includes the following steps:

[0011] S1, make a hole in the outer formwork of the bottom plate of the box culvert body. The vertical position of the hole is between the two layers of steel mesh of the bottom plate of the box culvert body. The horizontal distance between the center of the hole and the two ends of the box culvert body is one-quarter of the length of the box culvert body. The two ends of the hole are semi-circular.

[0012] S2. After the bottom slab reinforcement of the box culvert body is tied, the outer wall reinforcement of the bottom slab is cut off when it encounters the through hole. The lifting hole reinforcement is set near the opening of the outer formwork, and the reinforcement modeling and reinforcement stress calculation meet the lifting requirements.

[0013] S3, the concrete pouring of the box culvert body bottom slab is carried out in layers. The first layer is poured to the height of the bottom surface of the through hole forming device, and the through hole forming device is installed. Then the flat airbag is inflated until the flat airbag is completely filled into the through hole. Then the second layer of concrete is poured. The third layer is poured to the top elevation of the box culvert bottom slab. After the bottom slab has slightly solidified, the side walls and partition walls are poured.

[0014] S4. After the concrete reaches the demolding strength, deflate the flat airbag, remove the outer formwork of the box culvert, and then pull out the through hole forming device to form the through hole in the bottom plate of the box culvert.

[0015] Furthermore, the through-hole forming device includes a flat airbag and a rectangular steel pipe arranged above and below it, with a protective sleeve on the outside of the rectangular steel pipe; the protective sleeve is made of the same material as the flat airbag, and after the flat airbag is inflated, the protective sleeve fits tightly against the steel plate at the opening of the outer mold to prevent grout leakage.

[0016] Furthermore, the reinforcing bars for the lifting holes include U-shaped bars, straight bars, straight bars on the side walls of the box culvert, and longitudinal bars on the side walls of the box culvert. The U-shaped bars are arranged around the opening of the outer formwork, and the straight bars are vertically positioned above the U-shaped bars. The straight bars on the side walls of the box culvert are perpendicular to the straight bars in the lifting holes and are positioned on the side walls of the box culvert. The longitudinal bars on the side walls of the box culvert are parallel to the straight bars in the lifting holes and are positioned on the side walls of the box culvert, with the longitudinal bars and straight bars being perpendicular to each other.

[0017] Furthermore, in step S3 of the construction of the through-hole, the concrete pouring of the box culvert body's bottom slab is carried out in layers. The first layer is poured to the height of the bottom surface of the through-hole forming device. After vibration, the through-hole forming device is installed. The through-hole forming device includes a flat airbag and a layer of rectangular steel pipes above and below it. A sheath is provided on the outside of the rectangular steel pipes. The sheath is made of the same material as the flat airbag. After the flat airbag is inflated, the sheath fits tightly against the steel plate at the opening of the outer formwork. The rectangular steel pipes are evenly distributed, and then the flat airbag is inflated. The inflation pressure is controlled at 0.025-0.03MPa until the flat airbag is completely filled into the through-hole. Then, the second layer of concrete is poured, and the displacement of the flat airbag is observed when it is poured to the height of the top surface of the through-hole forming device. If displacement occurs, it is adjusted. The third layer is poured to the top elevation of the box culvert bottom slab. After the bottom slab has slightly solidified, the side walls and partition walls are poured.

[0018] The lifting, transporting, and installation method for the large box culvert hoisting device provided by this invention includes the following steps:

[0019] Step 1, hooking process: The lifting frame is positioned directly above the box culvert body. The crane ship winch is used to pass the lower sling through the through hole. The crane ship's auxiliary hook lifts the lower sling to the release double shackle and suspends it on the release double shackle.

[0020] Step 2, Lifting and Transportation: The crane vessel lifts the box culvert body off the shore and sails it to the waters where it will be installed;

[0021] Step 3, Water docking: After arriving at the installation area, the box culvert body is submerged in the water. Coarse positioning is performed using a rough positioning marker to quickly move the box culvert body to the installation position. Then, the total station prism or GPS receiver at the top of the precise positioning marker is observed to direct fine adjustments. Once the requirements are met, the culvert body is placed on the bottom.

[0022] Step 4, Automatic Unhooking: On the water, the lower shackle pin of the double shackle is released, the crane vessel lifts the hook, and the lower sling is pulled out from the through hole, thus completing the unhooking process.

[0023] Furthermore, in step 1, the hooking process is as follows: the crane vessel is positioned vertically on the shoreline of the prefabrication yard for the box culvert body, the upper sling is suspended on the main hook of the crane vessel, the lifting frame is positioned directly above the box culvert body, a thin steel wire rope is used as the guide rope, one end of the thin steel wire rope is connected to the lower sling, and the other end of the thin steel wire rope passes through the lifting hole and connects to the winch of the crane vessel. The winch is started, and the winch of the crane vessel passes the lower sling through the through hole. The auxiliary hook of the crane vessel lifts the lower sling to the unhooking double shackle and suspends it on the unhooking double shackle for hooking.

[0024] Furthermore, in step 2, after the hooking is completed, the crane vessel slowly loads the load until it is 0.5m off the ground to observe whether the lifting frame, upper sling, and lower sling are normal. Then the crane vessel weighs anchor and lifts the box culvert body off the shore and sails to the waters where it will be installed. In step 3, the outer side of the rough positioning marker is covered with a light-emitting sticker to facilitate rough positioning at night.

[0025] The lifting, transportation, and installation method for the large box culvert hoisting device provided by this invention has the following beneficial effects:

[0026] 1. This invention utilizes a through-hole forming device to create a smooth-edged through-hole in the bottom plate of the box culvert body, replacing the top lifting ring of the box culvert body. This saves on the customization, processing, and mechanical installation processes required for the top lifting ring of the box culvert using the ceiling method, and avoids the problem of corrosion and damage to the concrete caused by the lifting ring being exposed to water. Simultaneously, it enables double-layer or multi-layer prefabrication of box culverts, simplifying the process and reducing construction costs.

[0027] 2. The through-hole forming device of the present invention can ensure that the main load-bearing reinforcement and overall strength of the box culvert body are not damaged in the gap between the upper and lower layers of steel mesh on the bottom plate of the box culvert body, and can also ensure that the corners of the through hole are smooth and do not damage the lower suspension cable. In addition, the flat airbag can be reused, which can save costs.

[0028] 3. This invention innovates the underwater installation process for large box culverts. The hoisting frame is equipped with coarse and precise positioning markers, and water-based positioning is adopted, improving underwater positioning to water-based positioning. It eliminates the need for tide-based measurement technology and underwater measurement and positioning by divers, enabling precise installation around the clock. It solves the industry problems of long tide-based installation time, long underwater line laying and unhooking time, and long measurement and positioning time for large box culverts constructed on land. It achieves safety innovation and reduces safety risks.

[0029] 4. This invention utilizes the winch of a crane vessel to quickly pass the lower sling through the through-hole. After the box culvert enters the water, the crane vessel lifts the hook, and the lower sling is pulled out through the through-hole. For the first time, it achieves automatic unhooking without the need for underwater unhooking by divers, thus improving work efficiency.

[0030] 5. This invention uses a flat rubber airbag as a core mold to form a through-hole. Inflating it completes the mold support, and deflating it and removing it completes the mold disassembly. It is quick to support and disassemble, and easy to construct. It solves the problem of difficulty in supporting and disassembling molds when using steel plates or wooden boards as core molds. The technology is advanced, the process is simple, and the installation efficiency is improved.

[0031] This invention eliminates the need for non-recoverable large-scale construction measures such as the top lifting ring of the box culvert using a crane vessel or the special inclined ramp of the airbag floating method. The through-hole and lifting frame structures are simple, combining rigidity and flexibility, thus reducing construction costs. Precise installation is possible without waiting for tides, and automatic detachment occurs when the hook is removed from the water, solving the construction problems of long waiting times for tides, long measurement and positioning times, long underwater line laying times, and long underwater detachment times associated with conventional processes. Therefore, this invention offers the advantages of facilitating the lifting of large box culverts, eliminating the need for underwater detachment operations by divers, enabling the prefabrication of double or multi-layer box culverts, simplifying operation, facilitating use, improving construction efficiency, and saving construction costs. Attached Figure Description

[0032] The accompanying drawings disclose specific embodiments of the present invention, wherein,

[0033] Figure 1 This is a schematic diagram of the structure of the present invention;

[0034] Figure 2 This is a schematic diagram of the through-hole forming device of the present invention;

[0035] Figure 3 This is a structural cross-sectional view of the through-hole forming device of the present invention;

[0036] Figure 4 This is a schematic diagram of the reinforcing steel bar for lifting holes according to the present invention;

[0037] Figure 5 This is a side view of the reinforcing steel bar in the lifting hole of the present invention;

[0038] Figure 6 This is the stress design calculation diagram of the reinforcing steel bars of the box culvert body and the reinforcing steel bars of the lifting holes according to the present invention;

[0039] Figure 7 This is the concrete stress design verification diagram of the box culvert body under lifting state according to the present invention;

[0040] Figure 8 This is the design calculation diagram of concrete deformation of the box culvert body under lifting state according to the present invention;

[0041] Figure 9 This is a diagram showing the usage state of the present invention;

[0042] Reference numerals: 1. Box culvert body; 2. Through-hole; 3. Through-hole forming device; 31. Flat airbag; 32. Rectangular steel pipe; 33. Sheath pipe; 4. Lifting hole reinforcing steel; 41. Lifting hole U-shaped reinforcement; 42. Lifting hole straight reinforcement; 43. Box culvert side wall straight reinforcement; 44. Box culvert side wall longitudinal reinforcement; 5. Upper lifting sling; 6. Lifting frame; 61. Reinforcing rod; 62. Support rod; 63. Coarse positioning marker; 64. Precise positioning marker; 65. Total station prism or GPS receiver; 7. Lower lifting sling; 8. Unhooking double shackle; 9. Crane boat. Detailed Implementation

[0043] like Figure 1-5 As shown, the large box culvert hoisting device provided by the present invention includes a box culvert body 1 and an upper hoisting cable 5. The bottom plate of the box culvert body 1 is provided with two symmetrical through holes 2. The lower hoisting cable 7 passes through the through holes 2 and is fixed to the hoisting frame 6. The through holes 2 are located between two layers of steel mesh on the bottom plate of the box culvert body 1. The horizontal distance between the center of the through holes 2 and the two ends of the box culvert body 1 is one-quarter of the length of the box culvert body 1. The two ends of the through holes 2 are semi-circular. The through holes 2 are 50mm away from the steel reinforcement of the bottom plate of the box culvert body 1. The dimensions are 750mm in length and 140mm in height, which is to reserve the thickness of the steel reinforcement protective layer. The upper hoisting cable 5 is provided at the top of the four corners of the hoisting frame 6.

[0044] Example 1:

[0045] like Figure 9 As shown, in use, the present invention first positions the lifting frame 6 directly above the culvert body 1. The winch of the crane vessel is used to pass the lower sling 7 through the through-hole 2, and the auxiliary hook of the crane vessel 9 lifts the lower sling 7 onto the lifting frame 6. Then, the crane vessel 9 lifts the culvert body 1 off the shore and sails to the installation area. Finally, upon reaching the installation area and after the culvert body 1 enters the water, the crane vessel 9 lifts the hook, and the lower sling 7 is pulled out through the through-hole 2, thus completing the unhooking process. This invention utilizes the crane vessel winch to quickly pass the lower sling 7 through the through-hole 2. After the culvert enters the water, the crane vessel lifts the hook, and the lower sling 7 is pulled out through the through-hole. For the first time, it achieves automatic unhooking without the need for underwater unhooking by divers; unhooking on the surface is automatic, improving efficiency. Simultaneously, this invention uses a through-hole forming device to create a smooth-edged through-hole in the bottom plate of the culvert body, replacing the top lifting ring of the culvert body. This allows for the prefabrication of double or multi-layer culverts, and the process is simple, reducing construction costs. Example 2:

[0046] like Figure 1As shown, two pairs of coarse positioning markers 63 are set at the top of the four corners of the lifting frame 6, and precise positioning markers 64 are set at the front and rear ends of the lifting frame 6. A release double shackle 8 is set at the bottom of the lifting frame 6; a total station prism or GPS receiver 65 is set at the top of the precise positioning markers 64; and a lower sling 7 is set on the release double shackle 8. After the crane vessel 9 lifts the box culvert body 1 to the installation water area, the crane vessel 9 slowly lifts the hook until the box culvert body 1 enters the water, until the two pairs of coarse positioning markers 63 are basically level with the line of sight of the crane vessel 9 commander. The crane vessel 9 commander uses the coarse positioning markers 63 to perform coarse positioning, so as to quickly move the box culvert body 1 to the installation position. The outer side of the coarse positioning markers 63 is covered with luminous stickers to facilitate coarse positioning at night; then the total station prism or GPS receiver 65 at the top of the precise positioning markers 64 is observed, and fine adjustment is directed. After fine adjustment is completed and the requirements are met, the hook is lifted and placed on the bottom. The lower locking pin of the double locking ring 8 is manually released on water. The crane vessel lifts the hook, and the lower sling 7 can be pulled out from the through hole 2, thus completing the unhooking process.

[0047] This invention innovates the underwater installation process for large box culverts. The hoisting frame is equipped with coarse and precise positioning markers, and the positioning is done on the water. This improves the underwater positioning process by making it a water-based one, eliminating the need for tide-based measurement technology and underwater measurement and positioning operations by divers. It enables precise installation around the clock, solving the industry problems of long tide-based, underwater line laying and unhooking, and measurement and positioning time for large box culverts built on land. This invention achieves safety innovation and reduces safety risks. Example 3:

[0048] like Figure 1 As shown, a reinforcing rod 61 is installed in the middle of the lifting frame 6, and support rods 62 are installed at the four corners of the lifting frame 6 and on both sides of the reinforcing rod 61; precision positioning markers 64 are installed at the front and rear ends of the reinforcing rod 61. The reinforcing rod 61 and support rods 62 can enhance the supporting force and stability of the lifting frame 6, making it easier for the crane vessel 9 to be lifted, transported, and installed via the lifting frame 6, thus improving safety. Example 4:

[0049] like Figure 2-3 As shown, the construction of the through-hole 2 of the present invention includes the following steps:

[0050] S1, make a hole in the outer formwork of the bottom plate of the box culvert body 1. The vertical position of the hole is between the two layers of steel mesh in the bottom plate of the box culvert body 1. The horizontal distance between the center of the hole and the two ends of the box culvert body 1 is one-quarter of the length of the box culvert body 1. The two ends of the hole are semi-circular.

[0051] S2, After the bottom slab reinforcement of the box culvert body 1 is tied, the outer wall reinforcement of the bottom slab is interrupted when it encounters the through hole. A lifting hole reinforcement 4 is installed near the opening of the outer formwork, and as follows... Figure 6-8As shown, this invention takes a 460t three-hole box culvert as an example and provides reinforcing steel bars for the lifting holes. In actual construction, the reinforcing steel bars are set according to the weight and size of the box culvert; the steel bar modeling and calculation are performed to meet the lifting requirements.

[0052] S3, the concrete pouring of the bottom slab of the box culvert body 1 is carried out in layers. The first layer is poured to the height of the bottom surface of the through hole forming device 3, and the through hole forming device 3 is installed. Then the flat airbag is inflated until the flat airbag is completely filled into the through hole. Then the second layer of concrete is poured to the height of the top surface of the through hole forming device 3. The third layer is poured to the top elevation of the bottom slab of the box culvert. After the bottom slab has slightly solidified, the side walls and partition walls are poured.

[0053] S4. After the concrete reaches the demolding strength, deflate the flat airbag, remove the outer formwork of the box culvert, and then pull out the through hole forming device to form the through hole 2 in the bottom plate of the box culvert.

[0054] The aforementioned through-hole forming device 3 includes a flat airbag 31 and a rectangular steel pipe 32 arranged above and below it. A sheath 33 is provided on the outside of the rectangular steel pipe 32. The sheath 33 and the flat airbag 31 are made of the same material. After the flat airbag 31 is inflated, the sheath 33, supported by the rectangular steel pipe 32, forms a rigid plane that tightly fits against the strip-shaped pads on the reinforcing mesh at the opening of the through-hole duct 2 of the outer formwork of the large box culvert 1, forming a uniform reinforcing steel protective layer thickness and preventing the reinforcing steel protective layer from being wavy. The sheath 33 is elastic and can fit tightly against the opening of the outer formwork of the bottom plate to prevent grout leakage.

[0055] The through-hole forming device of the present invention, in the gap between the upper and lower layers of steel mesh on the bottom plate of the box culvert body, can ensure that the main load-bearing reinforcement and overall strength of the box culvert body are not damaged, and can also ensure that the corners of the through hole are smooth and do not damage the upper suspension cable. In addition, the flat airbag can be reused, which can save costs.

[0056] The aforementioned reinforcing bars 4 for lifting holes include lifting hole U-shaped bars 41, lifting hole straight bars 42, box culvert sidewall straight bars 43, and box culvert sidewall longitudinal bars 44. The lifting hole U-shaped bars 41 are wrapped around the opening position of the outer formwork, and the lifting hole straight bars 42 are vertically arranged above the lifting hole U-shaped bars 41. The box culvert sidewall straight bars 43 are arranged perpendicularly to the lifting hole straight bars 42 on the box culvert sidewall. The box culvert sidewall longitudinal bars 44 are arranged parallel to the lifting hole straight bars 42 on the box culvert sidewall, and the box culvert sidewall longitudinal bars 44 and the box culvert sidewall straight bars 43 are arranged perpendicular to each other. Example 5:

[0057] like Figure 2-3 As shown, the construction of the through-hole 2 of the present invention includes the following steps:

[0058] S1. An opening is made between the two layers of steel mesh on the bottom plate of the box culvert body 1. The opening is 750mm long and 140mm high. The bottom of the opening is 50mm away from the steel reinforcement on the bottom plate of the box culvert body 1, which is to reserve the thickness of the steel reinforcement protective layer. The horizontal distance between the center of the opening and the two ends of the box culvert body 1 is one-quarter of the length of the box culvert body 1. The two ends of the opening are semi-circular.

[0059] S2, after the bottom slab reinforcement of the box culvert body 1 is tied, the outer wall reinforcement of the bottom slab is cut off at the through-hole, and a protective layer thickness of 50mm is reserved; at the same time, lifting hole reinforcing bars 4 are set near the opening of the outer formwork; the lifting hole reinforcing bars 4 include lifting hole U-shaped bars 41, lifting hole straight bars 42, box culvert side wall straight bars 43 and box culvert side wall longitudinal bars 44. The lifting hole U-shaped bars 41 are wrapped around the opening of the outer formwork, and the lifting hole straight bars 42 are set vertically above the lifting hole U-shaped bars 41; the box culvert side wall straight bars 43 are set vertically on the box culvert side wall, and the box culvert side wall longitudinal bars 44 are set parallel to the lifting hole straight bars 42 on the box culvert side wall. Furthermore, the longitudinal reinforcement 44 and the straight reinforcement 43 of the box culvert sidewall are set perpendicular to each other; in specific implementation, the lifting hole reinforcing bars 4 are set according to the weight and size of the box culvert body 1. Taking a 460t three-hole box culvert as an example, the lifting hole U-shaped reinforcement 41 is a U-shaped reinforcement, using rib steel with a diameter of 22mm, 1800mm long, and 200mm high; the lifting hole straight reinforcement 42 is a straight reinforcement, using rib steel with a diameter of 18mm and a length of 1080mm; the box culvert sidewall straight reinforcement 43 is a straight reinforcement, using rib steel with a diameter of 18mm and a length of 1800mm; the box culvert sidewall longitudinal reinforcement 44 is a straight reinforcement, using rib steel with a diameter of 22mm and a length of 540mm. Figure 6-8 As shown, this invention uses a 460t three-span box culvert as an example, with reinforcing steel bars for the lifting holes. In actual construction, the reinforcing steel bars are set according to the weight and dimensions of the box culvert. The reinforcing steel bars for the lifting holes are modeled and their stress calculated to meet the lifting requirements.

[0060] S3, the concrete pouring of the bottom slab of the box culvert body 1 is carried out in layers. The first layer is poured to the height of the bottom surface of the through-hole forming device 3. After vibration, the through-hole forming device 3 is installed. The through-hole forming device 3 includes a flat airbag 31 and a layer of rectangular steel pipes 32 above and below it. A sheath 33 is set on the outside of the rectangular steel pipes 32. The sheath 33 and the flat airbag 31 are made of the same material. After the flat airbag 31 is inflated, the sheath 33 is tightly fitted to the steel plate of the outer formwork opening. The rectangular steel pipes 32 are evenly distributed, and then the flat airbag 31 is inflated. The inflation pressure is controlled at 0.025-0.03MPa until the flat airbag 31 is completely filled into the through hole. Then the second layer of concrete is poured. The flat airbag 31 is observed to be displaced when it is poured to the height of the top surface of the through-hole forming device 3. If displacement occurs, it is adjusted. The third layer is poured to the top elevation of the bottom slab of the box culvert. After the bottom slab has slightly solidified, the side walls and partition walls are poured.

[0061] S4. After the concrete reaches the demolding strength, deflate the flat airbag, remove the outer formwork of the box culvert, and then pull out the through hole forming device to form the through hole 2 in the bottom plate of the box culvert. Example 6:

[0062] like Figure 9 As shown, the method for lifting, transporting, and installing a large box culvert hoisting device includes the following steps:

[0063] Step 1, hooking process: The upper sling 5 is suspended on the main hook of the crane vessel 9, the lifting frame 6 is positioned directly above the box culvert body 1, the crane vessel winch is used to pass the lower sling 7 through the through hole 2, the auxiliary hook of the crane vessel 9 lifts the lower sling 7 to the unhooking double shackle 8 and suspends it on the unhooking double shackle 8 of the lifting frame 6.

[0064] Step 2, Lifting and Transportation: The crane vessel 9 lifts the box culvert body 1 off the shore and sails it to the waters where it will be installed;

[0065] Step 3, Water docking: After arriving at the installation area, the box culvert body 1 is submerged in the water. Coarse positioning is performed using the coarse positioning marker 63 to quickly move the box culvert body 1 to the installation position. Then, the total station prism or GPS receiver 65 on the top of the precise positioning marker 64 is observed to direct fine adjustments. Once the requirements are met, the culvert body is placed on the bottom.

[0066] Step 4, Automatic Unhooking: On the water, the lower locking pin of the double locking ring 8 is released, the crane vessel 9 lifts the hook, and the lower sling 7 is pulled out from the through hole 2, thus completing the unhooking.

[0067] This invention innovates the underwater installation process for large box culverts. The hoisting frame is equipped with coarse and precise positioning markers, and the positioning is done on the water. This improves the underwater positioning process by replacing the traditional underwater positioning with a water-based one. It eliminates the need for tide-based measurement technology and underwater measurement and positioning by divers, enabling precise installation around the clock. This invention solves the industry problems of long tide-based installation time, long underwater line laying and unhooking time, and long measurement and positioning time for large box culverts built on land. It achieves safety innovation and reduces safety risks.

[0068] This invention boasts advanced technology, simplified procedures, and improved installation efficiency. It utilizes a crane vessel's winch to quickly thread the lower sling 7 through the through-hole 2. After the box culvert enters the water, the crane vessel lifts the hook, and the lower sling is pulled out through the through-hole. This is the first time that underwater unhooking operations by divers are eliminated; the hook can be automatically released from the water, significantly improving efficiency. Furthermore, this invention uses a through-hole forming device to create a smoothly rounded through-hole in the bottom plate of the box culvert body, replacing the top lifting ring of the box culvert body. This allows for the prefabrication of double- or multi-layer box culverts, and the simple process reduces construction costs. Example 7:

[0069] like Figure 9 As shown, the method for lifting, transporting, and installing a large box culvert hoisting device includes the following steps:

[0070] Step 1, hooking process: The 700t crane vessel 9 is positioned on the shore of the prefabrication yard of the vertical box culvert body 1. The upper sling 5 is suspended on the main hook of the crane vessel 9. The lifting frame 6 is positioned directly above the box culvert body 1. A thin steel wire rope is used as the guide rope. One end of the thin steel wire rope is connected to the lower sling 7. The other end of the thin steel wire rope passes through the lifting hole and connects to the winch of the crane vessel 9. The winch is started. The winch of the crane vessel passes the lower sling 7 through the through hole 2. The auxiliary hook of the crane vessel 9 lifts the lower sling 7 to the unhooking double shackle 8 and suspends it on the unhooking double shackle 8 of the lifting frame 6 for hooking.

[0071] Step 2, Lifting and Transportation: After the hook is completed, the crane vessel 9 slowly loads the load until it is 0.5m off the ground. Observe whether the lifting frame 6, the upper sling 5 and the lower sling are normal. Then the crane vessel 9 weighs anchor and lifts the box culvert body 1 off the shore and sails to the water area to be installed.

[0072] Step 3, Water Docking: After arriving at the installation area, the crane vessel 9 slowly hooks the box culvert body 1 into the water from the sea level until the two pairs of coarse positioning markers 63 are roughly level with the line of sight of the crane vessel 9 commander. The crane vessel 9 commander uses the coarse positioning markers 63 to perform coarse positioning, so as to quickly move the box culvert body 1 to the installation position. The outer side of the coarse positioning markers 63 is covered with light-emitting stickers to facilitate coarse positioning at night. Then, the total station prism or GPS receiver 65 on the top of the precision positioning markers 64 is observed, and fine adjustment is directed. After fine adjustment is completed and the requirements are met, the crane vessel is hooked and placed on the bottom.

[0073] Step 4, Automatic Unhooking: Manually detach the lower shackle pin of the double shackle 8 on the water. The crane vessel lifts the hook, and the lower sling 7 can be pulled out from the through hole 2, thus completing the unhooking.

[0074] Taking the relocation of the drainage outlet of the Phase II 2×1000MW supercritical coal-fired power generating unit project of Fujian Shishi Hongshan Thermal Power Plant as an example, this project prefabricated a total of 36 large drainage box culverts. Considering the hydrological and meteorological conditions, the efficiency of box culvert transportation and installation using conventional technology is 1 culvert / day. By applying the lifting, transportation and installation method of the large box culvert hoisting device of this invention, the efficiency of box culvert transportation and installation is increased to 3 culverts / day, the construction period is shortened by 24 days, and the hoisting process of a single large box culvert is shortened from 5-7 hours of conventional technology to 3.6 hours, achieving the expected goals of high efficiency, safety and low cost.

[0075] In the drainage outlet relocation project of the Fujian Shishi Hongshan Thermal Power Plant Phase II 2×1000MW supercritical coal-fired power generating unit project, which we undertook, we completed the transportation and installation of 36 large prefabricated box culverts with high quality and efficiency. Taking the drainage outlet relocation project of the Fujian Shishi Hongshan Thermal Power Plant Phase II 2×1000MW supercritical coal-fired power generating unit project as an example, the construction cost comparison between this invention and the crane ship ceiling method is as follows:

[0076] Cost Comparison Calculation Table

[0077]

[0078] This invention is applicable to the rapid installation of prefabricated large single-hole, double-hole, and triple-hole drainage box culverts on land, as well as the rapid installation of other similar components on water under the same working conditions.

[0079] This invention eliminates the need for non-recoverable large-scale construction measures such as the top lifting ring of the box culvert using a crane vessel or the special inclined ramp for airbag floating. The through-hole and lifting frame of this invention feature a simple, rigid-flexible structure, reducing construction costs. It allows for precise installation without waiting for tides, and automatic detachment via underwater unhooking, solving the construction problems of long installation times due to tides, long measurement and positioning times, long underwater line laying times, and long underwater unhooking times in conventional processes. In practice, it demonstrates the characteristics of simple operation, speed, economy, safety, and reliability, showing significant advancements in improving construction progress and possessing strong practical significance for promoting the advancement of large box culvert transportation and installation technology.

Claims

1. A method for lifting, transporting, and installing a large box culvert hoisting device, the large box culvert hoisting device comprising the box culvert body (1) and upper hoisting cables (5), characterized in that, The bottom plate of the box culvert body (1) is provided with two symmetrical through holes (2). The lower sling (7) passes through the through holes (2) and is fixed on the hoisting frame (6). The through holes (2) are located between the two layers of steel mesh on the bottom plate of the box culvert body (1). The horizontal distance between the center of the through holes (2) and the two ends of the box culvert body (1) is one-quarter of the length of the box culvert body (1). The two ends of the through holes (2) are semi-circular. The through holes (2) are reserved for the thickness of the steel reinforcement protective layer. The top of the four corners of the hoisting frame (6) is provided with upper slings (5). The four corners of the hoisting frame (6) are provided with two pairs of rough positioning markers (63). The front and rear ends of the hoisting frame (6) are provided with precise positioning markers (64). The bottom of the hoisting frame (6) is provided with a release double shackle (8). The top of the precise positioning marker (64) is provided with a total station prism or GPS receiver (65). The release double shackle (8) is provided with a lower sling (7). The construction of the through-hole (2) includes the following steps: S1, make a hole in the outer formwork of the bottom plate of the box culvert body (1). The vertical position of the hole is between the two layers of steel mesh in the bottom plate of the box culvert body (1). The horizontal distance between the center of the hole and the two ends of the box culvert body (1) is one-quarter of the length of the box culvert body (1). The two ends of the hole are semi-circular. S2, After the bottom plate reinforcement of the box culvert body (1) is tied, the outer wall reinforcement of the bottom plate is cut off when it encounters the through hole (2). The lifting hole reinforcement (4) is set near the opening of the outer formwork, and the reinforcement stress is calculated to meet the hoisting requirements after reinforcement modeling; S3, the concrete pouring of the bottom slab of the box culvert body (1) is carried out in layers. The first layer is poured to the bottom height of the through hole forming device (3) and the through hole forming device (3) is installed. Then the flat airbag is inflated until the flat airbag is completely filled to the through hole. Then the second layer of concrete is poured. The third layer is poured to the top elevation of the bottom slab of the box culvert. After the bottom slab has slightly solidified, the side walls and partition walls are poured. S4. After the concrete reaches the demolding strength, deflate the flat airbag, remove the outer formwork of the box culvert, and then pull out the bottom plate channel of the box culvert using the through hole forming device (3) to form the through hole (2). The method for lifting, transporting, and installing the large box culvert hoisting device includes the following steps: Step 1, hooking process: The hoisting frame (6) is positioned directly above the box culvert body (1). The hoisting vessel winch is used to pass the lower sling (7) through the through hole (2). The auxiliary hook of the hoisting vessel (9) lifts the lower sling (7) to the unhooking double shackle (8) and suspends it on the unhooking double shackle (8). Step 2, lifting and transportation: The crane vessel (9) lifts the box culvert body (1) off the shore and sails to the waters where it is to be installed; Step 3, Water docking: After arriving at the installation area, the box culvert body (1) is submerged in the water. Coarse positioning is performed using the coarse positioning marker (63) to quickly move the box culvert body (1) to the installation position. Then, the total station prism or GPS receiver (65) on the top of the precise positioning marker (64) is observed to direct fine adjustments. After meeting the requirements, the hook is placed on the bottom. Step 4, Automatic Unhooking: The lower shackle pin of the double shackle (8) is released on the water, the crane (9) lifts the hook, and the lower sling (7) is pulled out from the through hole (2), thus completing the unhooking.

2. The method for lifting, transporting, and installing the large box culvert hoisting device according to claim 1, characterized in that, A reinforcing rod (61) is provided in the middle of the hoisting frame (6), and support rods (62) are provided at the four corners of the hoisting frame (6) and on both sides of the reinforcing rod (61); a precision positioning marker (64) is provided at the front end and rear end of the reinforcing rod (61).

3. The method for lifting, transporting, and installing the large box culvert hoisting device according to claim 1, characterized in that, The through-hole forming device (3) includes a flat airbag (31) and a rectangular steel pipe (32) arranged above and below it. A sheath (33) is provided on the outside of the rectangular steel pipe (32). The sheath (33) and the flat airbag (31) are made of the same material. After the flat airbag (31) is inflated, the sheath (33) is tightly fitted with the steel plate at the opening of the outer mold to prevent grout leakage.

4. The method for lifting, transporting, and installing the large box culvert hoisting device according to claim 1, characterized in that, The lifting hole reinforcing bars (4) include lifting hole U-shaped bars (41), lifting hole straight bars (42), box culvert side wall straight bars (43) and box culvert side wall longitudinal bars (44). The lifting hole U-shaped bars (41) are wrapped around the opening position of the outer formwork, and the lifting hole straight bars (42) are vertically arranged above the lifting hole U-shaped bars (41). The box culvert side wall straight bars (43) are arranged perpendicular to the lifting hole straight bars (42) on the box culvert side wall. The box culvert side wall longitudinal bars (44) are arranged parallel to the lifting hole straight bars (42) on the box culvert side wall, and the box culvert side wall longitudinal bars (44) and the box culvert side wall straight bars (43) are arranged perpendicular to each other.

5. The method for lifting, transporting, and installing the large box culvert hoisting device according to claim 1, characterized in that, In S3 of the construction of the through-hole (2), the concrete pouring of the bottom slab of the box culvert body (1) is carried out in layers. The first layer is poured to the height of the bottom surface of the through-hole forming device (3). After vibration, the through-hole forming device (3) is installed. The through-hole forming device (3) includes a flat airbag (31) and a rectangular steel pipe (32) set above and below it. The outer side of the rectangular steel pipe (32) is provided with a sheath (33). The sheath (33) and the flat airbag (31) are made of the same material. After the flat airbag (31) is inflated, the sheath... The tube (33) is tightly fitted with the steel plate at the opening of the outer mold; and the rectangular steel tube (32) is evenly arranged, and then the flat airbag (31) is inflated. The inflation pressure is controlled at 0.025-0.03MPa until the flat airbag (31) is completely filled into the through hole; then the second layer of concrete is poured, and the flat airbag (31) is observed to be displaced when the top surface of the through hole forming device (3) is reached. If displacement occurs, it is adjusted; the third layer is poured to the top elevation of the box culvert bottom plate; after the bottom plate has slightly solidified, the side walls and partition walls are poured.

6. The method for lifting, transporting, and installing the large box culvert hoisting device according to claim 1, characterized in that, In step 1, the hooking process is as follows: the crane ship (9) is positioned vertically on the shore of the prefabrication yard of the box culvert body (1), the upper sling (5) is suspended on the main hook of the crane ship (9), the lifting frame (6) is positioned directly above the box culvert body (1), a thin steel wire rope is used as the guide rope, one end of the thin steel wire rope is connected to the lower sling (7), and the other end of the thin steel wire rope passes through the lifting hole and is connected to the winch of the crane ship (9). The winch is started, and the winch of the crane ship passes the lower sling (7) through the through hole (2). The auxiliary hook of the crane ship (9) lifts the lower sling (7) to the unhooking double shackle (8) and hangs it on the unhooking double shackle (8) for hooking.

7. The method for lifting, transporting, and installing the large box culvert hoisting device according to claim 1, characterized in that, In step 2, after the hooking is completed, the crane vessel (9) slowly loads the load until it is 0.5m off the ground to observe whether the lifting frame (6), upper sling (5) and lower sling (7) are normal. Then the crane vessel (9) weighs anchor and lifts the box culvert body (1) off the shore and sails to the water area to be installed. In step 3, the outer side of the rough positioning marker (63) is covered with a light-emitting sticker to facilitate rough positioning at night.

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