A secondary floating casting type immersed tube structure and secondary floating casting method

Abstract

The present invention relates to a secondary floating cast type submerged tube structure and a secondary floating cast method. A secondary floating cast type submerged tube structure comprises a top plate, a bottom plate and a wall body, wherein the top plate comprises a first cast layer and a layer to be cast, and the layer to be cast is located above the first cast layer. The cast first cast layer can cooperate with the bottom plate and the wall body to form a stable structure, which can remain stable during floating transportation, that is, the uncast layer to be cast will not affect the safety of floating transportation; by reserving the uncast layer to be cast, the secondary floating cast type submerged tube structure is lighter than the complete submerged tube structure, requires a shallower draft during floating transportation, is easier to float, and improves the safety of floating transportation, and can reduce the excavation and deepening of the river below the floating line, which can save engineering investment, and after the secondary floating casting of the layer to be cast, a complete top plate is formed, which can ensure the quality and safety of the submerged tubes used in the foundation pit.

Description

Technical Field

[0001] The present invention relates to the technical field of immersed tubes, in particular to a secondary floating casting type immersed tube structure and a secondary floating casting method. Background Art

[0002] Currently, immersed tube construction projects both domestically and internationally can be broadly categorized into three structural types: early steel-shell immersed tubes (single-layer / double-layer), the widely used reinforced concrete-reinforce ... Summary of the Invention

[0003] The purpose of the present invention is to provide a secondary floating cast type submerged tube structure and a secondary floating casting method to address the problems in the prior art of difficulty in floating submerged tubes and low floating safety factor when the water depth for floating submerged tubes is difficult to meet.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A secondary floating cast-type immersed tube structure comprises a top plate, a bottom plate and a wall, wherein the top plate comprises a first cast layer and a layer to be cast, and the layer to be cast is located above the first cast layer.

[0006] With the secondary floating cast-in-place submerged tube structure described in this solution, a portion of the top plate of the submerged tube structure is cast to form a first cast layer, and a portion is reserved above the first cast layer as a layer to be cast that is not cast before floating. The cast first cast layer can cooperate with the bottom plate and wall to form a stable structure that can remain stable during floating, that is, the uncast layer to be cast will not affect the safety of floating. After the secondary floating cast-in-place submerged tube structure is floated, if the secondary floating cast-in-place submerged tube structure is first floated to a storage area next to the foundation pit, the layer to be cast of the secondary floating cast-in-place submerged tube structure is subjected to secondary floating casting in the storage area to form a complete top plate structure, so that the submerged tube structure is complete and will not affect the safety of use in the foundation pit. The first cast layer can serve as a casting bottom template for the layer to be cast, facilitating the secondary floating casting of the first cast layer on the water.

[0007] Moreover, because the top plate of the secondary floating cast-in-place immersed tube structure has an uncast layer to be cast, the secondary floating cast-in-place immersed tube structure is lighter than a complete immersed tube structure, and the secondary floating cast-in-place immersed tube structure requires a shallower draft during floating transportation, making the floating transportation of the secondary floating cast-in-place immersed tube structure easier and improving the safety of floating transportation; and it can reduce the excavation and deepening of the river below the floating route, thereby saving project investment.

[0008] Preferably, the layer to be cast is located in the middle of the horizontal plane of the top plate, and the layer to be cast is symmetrical about the longitudinal center axis of the top plate, which facilitates the balance of the secondary floating cast-in-place immersed tube structure on the water and facilitates balance control during floating transportation.

[0009] Preferably, the layer to be cast is surrounded by a second cast layer, and the width of the second cast layer on both sides of the top plate accounts for more than 10% of the width of the top plate; the thickness of the first cast layer accounts for more than 30% of the thickness of the top plate.

[0010] The second cast layer ensures the structural strength of both ends and both sides of the top plate of the secondary floating cast submerged tube structure, and ensures the safe floating of the secondary floating cast submerged tube structure. The width of the second cast layer on both sides of the top plate accounts for more than 10% of the width of the top plate, which can ensure the connection strength between the top plate and the side wall. The thickness of the first cast layer accounts for more than 30% of the thickness of the top plate, which can ensure the amount of concrete of the layer to be cast during the secondary floating casting and ensure the safety of casting. And the second cast layer on all sides can be used as a side form for the later casting of the layer to be cast.

[0011] Preferably, a first weight-reducing component is provided in the reinforced concrete of the bottom plate and the wall, and the first weight-reducing component has a cavity that can be used for pouring concrete. Under the premise of ensuring floating safety, the first weight-reducing component is provided in the bottom plate and the wall, which can further reduce the deadweight of the secondary floating cast-in-place immersed tube structure, so that the secondary floating cast-in-place immersed tube structure requires a shallower draft during floating, making floating easier and improving the safety of floating.

[0012] and / or,

[0013] The second cast layers at both ends of the roof are equipped with second weight-reducing components, each containing a cavity for pouring concrete. The second weight-reducing components, installed within the second cast layers at both ends of the roof, further reduce the weight of the secondary floating cast-in-place immersed tube structure, enabling it to operate in shallower waters, making it easier and safer to float.

[0014] Preferably, when the first weight-reducing component is provided, the first weight-reducing component comprises a first embedded steel pipe transversely arranged in the bottom plate and a second embedded steel pipe vertically arranged in the wall, and the second embedded steel pipe is connected to the first embedded steel pipe;

[0015] When the second weight-reducing component is provided, the second weight-reducing component includes a third embedded steel pipe transversely arranged in the second cast layer, and the third embedded steel pipe has an upward communication port.

[0016] By using the above-mentioned first weight-reducing component, the base plate and the wall are well connected, and the wall and base plate can be greatly utilized to achieve weight reduction. When using the above-mentioned second weight-reducing component, the second cast layer can be used to set up a third embedded steel pipe, which can further achieve weight reduction without affecting the floating of the secondary floating cast-type submerged tube structure and the subsequent secondary floating casting. The third embedded steel pipe has an upward connecting port, which is always above the water surface during floating transportation, which can prevent water from entering the third embedded steel pipe; it is more convenient to pour concrete in the later stage, and the molding quality of the concrete poured into the third embedded steel pipe can be guaranteed.

[0017] Preferably, the wall body includes side walls on both sides and two middle walls in the middle, the side walls are provided with the second embedded steel pipe, and at least one of the middle walls is provided with the second embedded steel pipe, and the upper end of the second embedded steel pipe located in the middle wall extends upward from the top surface of the first cast layer or the top surface of the top plate;

[0018] The second pre-buried steel pipes of the second cast layer, which are located on the side wall and whose longitudinal positions correspond to the two ends of the top plate, extend vertically upward from the top surface of the top plate.

[0019] The second pre-buried steel pipe extends vertically upward from the top surface of the first cast layer or the top plate, and can be used for pouring and venting, preventing water from entering the pre-buried steel pipe. This also facilitates later concrete pouring and ensures the quality of the concrete poured into the pre-buried steel pipe, as well as the quality of the first weight-reducing component, resulting in better quality of the final immersed tube. The top ends of the second pre-buried steel pipes on both sides serve as pouring ports; the top end of the second pre-buried steel pipe located in the center wall serves as an exhaust port, ensuring pouring quality and better control of balance during pouring, making pouring safer.

[0020] Preferably, the upper end of the second embedded steel pipe located on the side wall and whose longitudinal position corresponds to the layer to be cast is connected to a fourth embedded steel pipe, and the fourth embedded steel pipe is transversely arranged in the second cast layer on both sides of the top plate, and the fourth embedded steel pipe is connected to the layer to be cast.

[0021] Installing fourth pre-buried steel pipes within the second cast layer on both sides of the roof further reduces the weight of the secondary floating cast-in-place structure by lightening the second cast layer, allowing the structure to operate at a shallower draft during transportation. Furthermore, the fourth pre-buried steel pipes connect to the corresponding second pre-buried steel pipes in the side walls and the corresponding first pre-buried steel pipes in the bottom slab, ensuring a stronger connection between the second cast layers on both sides of the bottom slab, side walls, and roof. This helps ensure the strength of the corners and overall strength of the secondary floating cast-in-place structure, and enhances safety during transportation and secondary floating casting.

[0022] Preferably, the layer to be poured is a groove opening upwards to facilitate pouring.

[0023] A secondary floating casting method comprises the following steps:

[0024] S1. Manufacturing the secondary floating cast-in-place immersed tube structure;

[0025] S2. Floating the secondary floating cast-in-place immersed tube structure to a storage area near the foundation trench;

[0026] S3. Anchoring the secondary floating cast-in-place immersed tube structure in the storage area by dropping anchor;

[0027] S4. Concrete is poured into the to-be-cast layer of the secondary floating cast-in-place immersed tube structure by pumping concrete to form a complete top plate.

[0028] The secondary floating casting method of the present invention, by reserving an uncast layer to be cast, makes the secondary floating cast submerged tube structure lighter than a complete submerged tube structure, and makes the secondary floating cast submerged tube structure require a shallower draft when floating to the storage area near the foundation pit, making the floating of the secondary floating cast submerged tube structure easier and improving the safety of floating, and can reduce the excavation and deepening of the river below the floating line, which can save project investment, and form a complete top plate after the secondary floating casting of the layer to be cast, which can ensure the quality and safety of the submerged tubes used in the foundation pit.

[0029] Preferably, in step S4, the concrete pumping can be completed by adopting method a or method b;

[0030] Method a: using a pump ship to pump concrete, the pump ship is anchored on the side of the secondary floating cast-in-place immersed tube structure, the pump ship is provided with a sky pump, the sky pump has a first pump pipe, and the first pump pipe is used to pump concrete;

[0031] Method b: Lay a second pump pipe from the shore to the layer to be poured.

[0032] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0033] 1. The secondary floating cast-in-place immersed tube structure of the present invention, by reserving an uncast layer to be cast, makes the secondary floating cast-in-place immersed tube structure lighter than a complete immersed tube structure, and makes the secondary floating cast-in-place immersed tube structure require a shallower draft during floating transportation, making the secondary floating cast-in-place immersed tube structure easier to float and improving the safety of floating transportation. It can also reduce the excavation and deepening of the river below the floating route, saving project investment. After the secondary floating casting of the layer to be cast, a complete top plate is formed, which can ensure the quality and safety of the immersed tubes used in the foundation pit.

[0034] 2. The secondary floating cast-in-place submerged tube structure described in the present invention is provided with a first weight-reducing component in the bottom plate and the wall, under the premise of ensuring the safety of floating transportation, which can further reduce the self-weight of the secondary floating cast-in-place submerged tube structure, so that the secondary floating cast-in-place submerged tube structure requires a shallower draft during floating transportation, which makes floating easier and improves the safety of floating transportation; a second weight-reducing component is provided in the second cast layer at both ends of the top plate, which can further reduce the self-weight of the secondary floating cast-in-place submerged tube structure, so that the secondary floating cast-in-place submerged tube structure requires a shallower draft during floating transportation, which makes floating easier and improves the safety of floating transportation.

[0035] 3. The secondary floating casting method of the present invention makes floating easier and improves the safety of floating, and can reduce the excavation and deepening of the river below the floating line, thereby saving project investment. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic structural diagram of the secondary floating cast-in-place immersed tube structure of the present invention;

[0037] Figure 2 yes Figure 1 Schematic diagram of the layout of the embedded steel pipe at AA in the middle;

[0038] Figure 3 yes Figure 1 Schematic diagram of the layout of the embedded steel pipe at the middle BB;

[0039] Figure 4 yes Figure 1 Schematic diagram of the layout of the embedded steel pipes at the CC;

[0040] Figure 5 yes Figure 1 Schematic diagram of the layout of the embedded steel pipes at the middle DD;

[0041] Figure 6 yes Figure 5 A partial enlarged schematic diagram of the middle circle;

[0042] Figure 7 yes Figure 1 Schematic diagram of the layout of the embedded steel pipes at EE;

[0043] Figure 8 yes Figure 1 Schematic diagram of the layout of the embedded steel pipes at the middle FF;

[0044] Figure 9 It is method a pumping concrete;

[0045] Figure 10 It is method b to pump concrete.

[0046] Icons: 11-top plate; 12-bottom plate; 13-side wall; 14-middle wall; 111-first cast layer; 112-second cast layer; 113-layer to be cast; 21-first embedded steel pipe; 22-second embedded steel pipe; 23-third embedded steel pipe; 24-fourth embedded steel pipe; 25-connecting steel pipe; 26-pouring port; 27-exhaust port; 3-pump boat; 31-sky pump; 32-first pump pipe; 33-first anchor chain; 34-first anchor block; 35-second anchor chain; 36-second anchor block; 4-second pump pipe; 5-protective pier; 51-groove. DETAILED DESCRIPTION

[0047] The present invention will be described in detail below with reference to the accompanying drawings.

[0048] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0049] Example 1

[0050] This embodiment provides a secondary floating cast-in-place immersed tube structure. Figure 1 and Figure 2 , including a top plate 11, a bottom plate 12 and a wall body, the wall body includes side walls 13 located on both sides and two middle walls 14 located in the middle, the top plate 11 includes a first cast layer 111 and a layer to be cast 113, and the layer to be cast 113 is located above the first cast layer 111.

[0051] With the secondary floating cast submerged tube structure described in this solution, a portion of the top plate 11 of the submerged tube structure is cast to form a first cast layer 111, and a portion is reserved above the first cast layer 111 as a to-be-cast layer 113 that is not cast before floating. The cast first cast layer 111 can cooperate with the bottom plate 12 and the wall to form a stable structure that can remain stable during floating. That is, the uncast to-be-cast layer 113 will not affect floating safety. After the secondary floating cast submerged tube structure is floated, the secondary floating cast submerged tube structure can be first floated to a storage area next to the foundation pit, and the to-be-cast layer 113 of the secondary floating cast submerged tube structure is cast in the storage area to form a complete top plate 11 structure. This ensures that the submerged tube structure is complete and does not affect its safety in the foundation pit. The first cast layer 111 can also serve as a bottom formwork for casting the to-be-cast layer 113, facilitating the secondary floating casting of the first cast layer 111 on water.

[0052] like Figure 1 As shown, Figure 1 The up and down direction is the horizontal direction of the immersed tube. Figure 1 The left and right directions are the longitudinal direction of the submerged tube. The layer to be cast 113 is located in the middle of the horizontal plane of the top plate 11, and the layer to be cast 113 is symmetrical about the longitudinal center axis of the top plate 11, which is convenient for the balance of the secondary floating cast submerged tube structure on the water and the balance control during floating transportation. And the layer to be cast 113 is surrounded by a second cast layer 112, and the second cast layer 112 on all sides can be used as a side mold for the later casting of the layer to be cast 113; and the second cast layer 112 ensures the structural strength of the two ends and both sides of the top plate 11 of the secondary floating cast submerged tube structure, and ensures the safety of the floating transportation of the secondary floating cast submerged tube structure. In this embodiment, the layer to be cast 113 is an upwardly open groove, which is convenient for casting. The width of the second cast layer 112 located on both sides of the top plate 11 accounts for more than 10% of the width of the top plate 11, which can ensure the connection strength between the top plate 11 and the side wall 13; such as Figure 2 As shown, the ratio of the thickness of the first poured layer 111 to the thickness of the top plate 11 is greater than 30%, which can ensure the amount of concrete of the layer to be poured 113 during the secondary floating pouring and ensure the pouring safety.

[0053] In this embodiment, because the top plate 11 of the secondary floating cast-in-place immersed tube structure includes an uncast precast layer 113, the secondary floating cast-in-place immersed tube structure is lighter than a complete immersed tube structure. This allows for a shallower draft during floating, making floating easier and safer. Furthermore, it reduces the need for excavation and deepening of the river below the floating route, saving project investment. This embodiment is applicable to both standard-interface immersed tubes and variable-section immersed tubes.

[0054] Example 2

[0055] This embodiment provides a secondary floating cast-in-place immersed tube structure, such as Figure 1-Figure 7 As shown, based on Example 1, a first weight-reducing component is further provided in the reinforced concrete of the bottom plate 12 and the wall. The first weight-reducing component has a cavity that can be used for pouring concrete. Under the premise of ensuring floating safety, the first weight-reducing component is provided in the bottom plate 12 and the wall to further reduce the deadweight of the secondary floating cast-in-place immersed tube structure, so that the secondary floating cast-in-place immersed tube structure requires a shallower draft during floating, making floating easier and improving floating safety.

[0056] and / or,

[0057] The second cast layers 112 at both ends of the roof 11 are equipped with second weight-reducing components, each containing a cavity for pouring concrete. The second weight-reducing components, installed within the second cast layers 112 at both ends of the roof 11, further reduce the weight of the secondary floating cast-in-place immersed tube structure, allowing for a shallower draft during floating, making it easier and safer to float.

[0058] Compared to the reinforced concrete structure of existing immersed tubes, the first and second weight-reducing components are lighter due to their inherent material and the presence of cavities. Replacing portions of the reinforced concrete structure of existing immersed tubes with the first and / or second weight-reducing components can make the tubes lighter and reduce their draft. Furthermore, the cavities of the first and second weight-reducing components aid buoyancy, further reducing the draft of the immersed tubes.

[0059] like Figure 2 、 Figure 3 and Figure 7 As shown, when the first weight-reducing component is provided, the first weight-reducing component includes a first embedded steel pipe 21 horizontally arranged in the bottom plate 12 and a second embedded steel pipe 22 vertically arranged in the wall, and the second embedded steel pipe 22 is connected to the first embedded steel pipe 21; by adopting the above-mentioned first weight-reducing component, the bottom plate 12 and the wall are well connected, and the wall and the bottom plate 12 can be greatly utilized to achieve weight reduction. The side wall 13 is provided with the second embedded steel pipe 22, and at least one of the middle walls 14 is provided with the second embedded steel pipe 22. The upper end of the second embedded steel pipe 22 located in the middle wall 14 extends upward from the top surface of the first cast layer 111 or the top surface of the top plate 11, as shown in FIG. Figure 2 and Figure 7 As shown, Figure 2 The upper end of the second embedded steel pipe 22 of the middle wall 14 extends upward from the top surface of the first cast layer 111. Figure 7The upper end of the second embedded steel pipe 22 of the middle wall 14 extends upward from the top surface of the top plate 11. Figure 1 and Figure 7 As shown, the second embedded steel pipe 22 located in the side wall 13 and corresponding to the second cast layer 112 at both ends of the top plate 11 vertically extends upward from the top surface of the top plate 11.

[0060] The second pre-buried steel pipe 22 extends vertically upward from the top surface of the first cast layer 111 or the top surface of the top plate 11. It can be used for pouring and exhaust, preventing water from entering the pre-buried steel pipe. It is also convenient for later concrete pouring and can ensure the molding quality of the concrete poured into the pre-buried steel pipe, ensure the casting quality of the first weight-reducing component, and improve the quality of the final immersed pipe. The top of the second pre-buried steel pipe 22 on both sides serves as a pouring port 26; the top of the second pre-buried steel pipe 22 located in the middle wall 14 serves as an exhaust port 27, which can ensure the casting quality and better control the balance during pouring, making the pouring safer.

[0061] like Figure 1-Figure 4 As shown, the upper end of the second embedded steel pipe 22 located on the side wall 13 and corresponding to the longitudinal position of the layer to be cast 113 is connected to a fourth embedded steel pipe 24. The fourth embedded steel pipe 24 is transversely arranged in the second cast layer 112 on both sides of the top plate 11. The fourth embedded steel pipe 24 is connected to the layer to be cast 113. The fourth embedded steel pipe 24 is connected to the pouring port 26 of the layer to be cast 113. After the concrete is poured in the layer to be cast 113, the pouring port 26 can be buried, which can ensure that the submerged pipe structure after the secondary floating casting is not easily damaged and is safer. The fourth embedded steel pipe 24 is arranged in the second cast layer 112 on both sides of the top plate 11. It can further reduce the deadweight of the secondary floating cast submerged pipe structure by reducing the second cast layer 112, so that the secondary floating cast submerged pipe structure requires a shallower draft during floating transportation. Moreover, the fourth embedded steel pipe 24 is connected with the corresponding second embedded steel pipe 22 in the side wall 13 and the corresponding first embedded steel pipe 21 in the bottom plate 12, which can ensure that the second cast layer 112 on both sides of the bottom plate 12, the side wall 13 and the top plate 11 are more strongly connected, which is beneficial to ensure the strength of the corners and the overall strength of the secondary floating cast submerged tube structure, and floating transportation and secondary floating casting are safer.

[0062] And as Figure 2 and Figure 3 As shown, the second embedded steel pipes 22 serving as the exhaust port 27 are staggered in the two middle walls 14 along the longitudinal direction of the immersed tube, which can ensure the strength of the middle wall 14 of the immersed tube while meeting the exhaust requirements and casting balance.

[0063] like Figure 5 and Figure 6As shown, when the second weight-reducing component is installed, it includes a third pre-embedded steel pipe 23 horizontally arranged within the second cast layer 112. The third pre-embedded steel pipe 23 has an upward-facing connection port. Specifically, the third pre-embedded steel pipe 23 is connected via a vertically arranged connecting steel pipe 25. The top end of the connecting steel pipe 25 extends upward through the top surface of the top plate 11 to form a connection port. The connection ports on both sides serve as pouring ports 26, and the connection port in the middle serves as an exhaust port 27. The exhaust port 27 corresponds to the top of the middle wall 14 and can be aligned vertically with the exhaust port 27 of the first weight-reducing component, facilitating pre-embedding. The pouring port 26 of the second weight-reducing component is also aligned vertically with the pouring port 26 of the first weight-reducing component as much as possible, facilitating pre-embedding and subsequent pouring. When using this second weight-reducing component, the third pre-embedded steel pipe 23 can be installed in the second cast layer 112, further reducing weight without affecting the floating operation of the secondary floating cast submerged tube structure and the subsequent secondary floating pouring. The third embedded steel pipe 23 has an upward connecting port, which is always above the water surface during floating, thus preventing water from entering the third embedded steel pipe 23 ; and it is more convenient to pour concrete later, and the molding quality of the concrete poured into the third embedded steel pipe 23 can be guaranteed.

[0064] like Figure 5-Figure 7 As shown, a protective pier 5 is provided on the outer surface of the immersed tube. This pier 5 serves as a collision protection structure for the immersed tube. In this embodiment, the protective pier 5 has a groove 51. At least a portion of the protective pier 5 is positioned corresponding to the communication port, and the communication port is located within the groove 51 of the corresponding protective pier 5. Specifically, at least a portion of the protective pier 5 is adjusted based on the position of the communication port so that the communication port is located within the groove 51 of the corresponding protective pier 5. This allows the protective pier 5 to not only protect the immersed tube from collision but also protect the communication port, ensuring smooth subsequent pouring.

[0065] like Figure 6 As shown, both ends of the third pre-buried steel tube 23 extend to the side walls 13 on either side, further reducing weight. The portion of the third pre-buried steel tube 23 extending to the side walls 13 is angled downward, adapting to the inward tilt of the immersed tube's corners and strengthening the connection between the top plate 11 and the side walls 13, improving the quality of the immersed tube.

[0066] When making a secondary floating cast-in-place immersed tube structure, the bottom plate 12 and the wall are cast together, and the top plate 11 is tied after the bottom plate 12 and the wall formwork are installed. The immersed tube is first tied with the bottom plate 12 and the wall reinforcement and the first embedded steel pipe 21 and the second embedded steel pipe 22 are buried inside. Then the large cavity of the formwork is entered, and then the top plate 13 reinforcement is tied and the third embedded steel pipe 23 is buried. In order to set the upward connecting port, such as Figure 8As shown, the left-right direction corresponds to the longitudinal direction of the immersed tube. In the sections corresponding to the second cast layers 112 at the longitudinal ends, the first and second weight-reducing components need to be staggered along the longitudinal direction of the immersed tube. Given the limited thickness of the top plate 13 and the space available for the protective layer and reinforcement, staggered placement helps ensure the structural strength of the top plate 11, improving its load-bearing properties and facilitating quality and safety control.

[0067] When manufacturing the above-mentioned secondary floating cast-in-place immersed tube structure, cooling water can be injected into the embedded steel pipe to improve the heat dissipation effect of the concrete and reduce the probability of cracks appearing on the concrete surface of the bottom plate, side wall or top plate; and the injected cooling water will not affect the quality of the secondary floating cast cavity in the later stage.

[0068] Example 3

[0069] This embodiment provides a secondary floating casting method, comprising the following steps:

[0070] S1. Producing the secondary floating cast-in-place immersed tube structure described in Example 1;

[0071] S2. Floating the secondary floating cast-in-place immersed tube structure to a storage area near the foundation trench;

[0072] S3. Anchoring the secondary floating cast-in-place immersed tube structure in the storage area by dropping anchor;

[0073] S4. Concrete is poured into the to-be-cast layer 113 of the secondary floating cast-in-place immersed tube structure by pumping concrete to form a complete top plate 11.

[0074] The secondary floating casting method described in this embodiment makes the secondary floating casting type submerged tube structure lighter than the complete submerged tube structure by reserving the uncast layer 113 to be cast, and makes the secondary floating casting type submerged tube structure require a shallower draft when floating to the storage area near the foundation pit, making the secondary floating casting type submerged tube structure easier to float and improving the safety of floating. It can also reduce the excavation and deepening of the river below the floating line, save engineering investment, and pre-embed the water stop strip in the to-be-cast layer and do a good job of joint surface treatment. Then, after the secondary floating casting of the to-be-cast layer, a complete top plate is formed, which can avoid construction joints in the top plate and avoid the risk of water leakage between the concrete cast in the to-be-cast layer and the first cast layer, and can ensure the quality and safety of the submerged tubes used in the foundation pit.

[0075] In step S4, the concrete pumping can be completed by adopting method a or method b;

[0076] Method a: A pump ship 3 is used to pump concrete. The pump ship 3 is anchored on the side of the secondary floating cast-in-place immersed tube structure. The pump ship 3 is provided with a sky pump 31. The sky pump 31 has a first pump pipe 32. The first pump pipe 32 is used to pump concrete. Figure 9 As shown, the pumpboat 3 is anchored to a first anchor block 34 via a first anchor chain 33, located within the underwater rock surface. The secondary floating cast-in-place immersed tube structure is anchored to a second anchor block 36 via a second anchor chain 35, also located within the underwater rock surface. This ensures the stability of the pumpboat 3 and the balance of the secondary floating cast-in-place immersed tube structure during casting. The pumpboat 3 can also move longitudinally along the immersed tube, anchoring at the corresponding longitudinal position of the next immersed tube and performing secondary floating casting at that location.

[0077] Method b: Lay the second pump pipe 4 from the shore to the layer to be poured 113. Figure 10 As shown, the second pump pipe 4 can be arranged on the water surface by providing a buoyancy-aiding structure, thereby reducing the impact and damage of water on the second pump pipe 4.

[0078] When the secondary floating cast-in-place immersed tube structure is the structure in Example 2, it is necessary to first use method a and method b to cast the concrete of the first embedded steel pipe 21, the second embedded steel pipe 22, the third embedded steel pipe 23, etc., and then use the strength after forming to cast the concrete of the layer to be cast 113 to form a complete top plate 11 to ensure casting safety.

[0079] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A secondary floating cast-in-place immersed tube structure, comprising a top plate (11), a bottom plate (12) and a wall, characterized in that: The top plate (11) comprises a first cast layer (111) and a layer to be cast (113), wherein the layer to be cast (113) is located above the first cast layer (111); the layer to be cast (113) is located in the middle of the horizontal plane of the top plate (11), and the layer to be cast (113) is symmetrical about the longitudinal center axis of the top plate (11); the layer to be cast (113) is surrounded by a second cast layer (112), and the width of the second cast layer (112) located on both sides of the top plate (11) accounts for more than 10% of the width of the top plate (11); the thickness of the first cast layer (111) accounts for more than 30% of the thickness of the top plate (11); The reinforced concrete of the bottom plate (12) and the wall is provided with a first weight-reducing component, the first weight-reducing component having a cavity, which can be used for pouring concrete; the second cast layer (112) located at both ends of the top plate (11) is provided with a second weight-reducing component, the second weight-reducing component having a cavity, which can be used for pouring concrete; in the portion of the second cast layer (112) corresponding to the longitudinal ends of the immersed tube, the first weight-reducing component and the second weight-reducing component are staggered along the longitudinal direction of the immersed tube; The first weight-reducing component comprises a first embedded steel pipe (21) disposed transversely in the bottom plate (12) and a second embedded steel pipe (22) disposed vertically in the wall, wherein the second embedded steel pipe (22) is connected to the first embedded steel pipe (21); The wall body comprises side walls (13) on both sides in the transverse direction and two middle walls (14) in the transverse middle, the side walls (13) being provided with the second embedded steel pipe (22), the upper end of the second embedded steel pipe (22) being located on the side walls (13) and corresponding to the layer to be cast (113) in the longitudinal direction being connected to a fourth embedded steel pipe (24), the fourth embedded steel pipe (24) being transversely arranged in the second cast layer (112) on both sides of the top plate (11), and the fourth embedded steel pipe (24) being connected to the layer to be cast (113); The second weight-reducing component comprises a third embedded steel pipe (23) transversely arranged in the second cast layer (112), and the third embedded steel pipe (23) has an upward communication port; A protective pier (5) is provided on the outer surface of the immersed tube, the protective pier (5) having a groove (51), at least part of the protective pier (5) is provided corresponding to the communication port, and the communication port is located inside the groove (51) corresponding to the protective pier (5).

2. The secondary floating cast-in-place immersed tube structure according to claim 1, characterized in that: At least one of the middle walls (14) is provided with the second embedded steel pipe (22), and the upper end of the second embedded steel pipe (22) located in the middle wall (14) extends upward from the top surface of the first cast layer (111) or the top surface of the top plate (11); The second embedded steel pipe (22) of the second cast layer (112) located on the side wall (13) and having a longitudinal position corresponding to both ends of the top plate (11) extends vertically upward from the top surface of the top plate (11).

3. A secondary floating casting method, characterized in that: The following steps are involved: S1. Producing a secondary floating cast-in-place immersed tube structure as described in any one of claims 1-2; S2. Floating the secondary floating cast-in-place immersed tube structure to a storage area near the foundation trench; S3. Anchoring the secondary floating cast-in-place immersed tube structure in the storage area by dropping anchor; S4, pouring concrete into the to-be-cast layer (113) of the secondary floating cast-in-place immersed tube structure by pumping concrete to form a complete top plate (11).

4. The secondary floating casting method according to claim 3, characterized in that: In step S4, concrete pumping is completed using method a or method b; Mode a: using a pump ship (3) to complete the pumping of concrete, wherein the pump ship (3) is anchored on the side of the secondary floating cast-in-place immersed tube structure, and the pump ship (3) is provided with a sky pump (31), wherein the sky pump (31) has a first pump pipe (32), and the first pump pipe (32) is used for pumping concrete; Mode b: Laying a second pump pipe (4) from the shore to the layer to be poured (113).

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