Construction method for ballast concrete in buoyancy tank

Abstract

The invention relates to the technical field of overwater construction, and provides a construction method for ballast concrete in a buoyancy tank, which comprises the following steps: S1, dividing the buoyancy tank into a plurality of pouring areas along the length direction of the buoyancy tank; s2, ballast concrete is poured into all the pouring areas, the pouring sequence is from the middle of the buoyancy tank to the two ends of the buoyancy tank, one pouring area is poured every n pouring areas during pouring, and n is larger than or equal to 1; s3, the step S2 is repeated until concrete pouring is completed in all the pouring areas; and S4, a prefabricated balancing weight is installed in the buoyancy tank, and the prefabricated balancing weight is used for adjusting the draft depth and posture balance of the buoyancy tank. The technical problems that in the prior art, ballast concrete in the buoyancy tank is poured in a cast-in-place mode, consequently, the buoyancy tank is prone to being unbalanced in stress, and the posture is unstable can be solved.

Description

Technical Field

[0001] The invention relates to the technical field of water construction, and in particular to a construction method of ballast concrete in a pontoon. Background Art

[0002] A pontoon is a water-retaining structure commonly used in water construction. It can block the water flow on one side, thereby creating dry construction conditions on the other side. A pontoon is generally a steel box structure, comprising a mid-tank, a ballast tank and a water pump. The mid-tank remains dry for storing equipment or as a working space, the ballast tank is used for filling or draining water, and the water pump is used to control the flow of water in and out of the ballast tank, thereby controlling the draft and attitude of the pontoon. However, since the unit weight of water does not meet the requirements for sitting on the bottom, only filling the ballast tank with water cannot stabilize the draft and attitude of the pontoon. During construction, it is often necessary to pour heavy aggregate ballast concrete on the bottom of the pontoon to increase the deadweight of the pontoon so as to meet the requirements for sitting on the bottom, so that the pontoon has sufficient draft and reduces the probability of the pontoon capsizing.

[0003] However, in the actual construction process, due to the low construction accuracy of cast-in-place ballast concrete, it is easy for the pontoon to become unstable due to unbalanced forces at various locations, resulting in various problems such as the pontoon's posture being unable to remain horizontal, unstable draft depth, and even capsizing. Summary of the invention

[0004] The purpose of the present invention is to overcome the technical problem in the prior art of using a cast-in-place method to cast ballast concrete in a pontoon, which causes the pontoon to be easily subjected to unbalanced forces and become unstable, and to provide a construction method for ballast concrete in a pontoon.

[0005] In a first aspect, the present invention provides a method for constructing ballast concrete in a pontoon, comprising the following steps:

[0006] S1, dividing the pontoon into a plurality of casting areas along the length direction of the pontoon;

[0007] S2. Pour ballast concrete into each pouring area. The pouring order is from the middle of the pontoon to both ends of the pontoon. During pouring, pour one pouring area every n pouring areas, where n≥1;

[0008] S3, repeat step S2 until all casting areas are cast;

[0009] When pouring ballast concrete, this scheme selects the pouring sequence from the middle to the two ends, that is, the pouring area located in the middle of the pontoon is poured first, and then the pouring areas located at the two ends of the pontoon are poured. The distance from the center of gravity of the ballast concrete poured first to the centroid of the pontoon is shorter, which can reduce the moment generated by the gravity of the ballast concrete on the pontoon, thereby being more conducive to maintaining the stability of the pontoon when the weight of the pontoon is small at the beginning of the pouring operation; and as the pouring operation gradually develops toward the two ends of the pontoon, the distance from the center of gravity of the ballast concrete poured later to the centroid of the pontoon gradually increases, so that the moment generated by the gravity of the ballast concrete poured later on the pontoon increases, but at this time the weight of the pontoon has also increased, so the influence of the moment generated by the gravity of the ballast concrete on the posture of the pontoon can still be suppressed. At the same time, pouring from the middle to the two ends is also conducive to balancing the moments generated by the ballast concrete at the left and right ends, thereby maintaining a constant posture of the pontoon.

[0010] At the same time, after the pouring of the ballast concrete is completed, this scheme installs additional prefabricated ballast weights in the pontoon. The prefabricated ballast weights can achieve better construction quality through better construction conditions in the factory, such as more accurate weight control and centroid measurement, so that the magnitude of the torque generated by the prefabricated ballast weights on the pontoon can be more accurately controlled by, for example, adjusting the installation position and installation quantity of the prefabricated ballast weights, and thus the posture of the pontoon can be more accurately adjusted so that the posture of the pontoon can reach the expected angle, such as horizontal.

[0011] This solution further selects to pour the ballast concrete at intervals in step S2, that is, skip pouring, which can prevent the ballast concrete from being poured too concentratedly, resulting in unbalanced force and deformation of the pontoon.

[0012] Preferably, the prefabricated ballast weight is located in the middle cabin of the pontoon.

[0013] Since water will not enter the middle cabin, this solution chooses to set the prefabricated ballast blocks in the middle cabin, which can avoid the water flow directly scouring and overlooking the prefabricated ballast blocks, causing damage to the prefabricated ballast blocks; at the same time, the dry environment in the middle cabin can also facilitate the installation and adjustment of the prefabricated ballast blocks.

[0014] Preferably, the number of prefabricated ballast weight blocks is at least two, and the prefabricated ballast weight blocks are distributed at both ends of the middle cabin along the length direction of the pontoon.

[0015] This scheme chooses to set the prefabricated ballast blocks at both ends of the middle cabin. While keeping the prefabricated ballast blocks in the middle cabin, it can maximize the distance from the center of gravity of the prefabricated ballast blocks to the centroid of the pontoon, that is, the lever arm of the gravity of the prefabricated ballast blocks, thereby obtaining a better pontoon attitude adjustment torque when the weight of the prefabricated ballast blocks is the same.

[0016] Preferably, step S2 further comprises the following step: adjusting the draft and posture balance of the pontoon by adjusting the thickness of the ballast concrete in each casting area.

[0017] This solution can adjust the posture of the pontoon when the prefabricated ballast weight is not installed; for example, if the draft depth on the left side of the pontoon increases, the pouring thickness of the ballast concrete on the right side of the pontoon can be increased; if the draft depth on the right side of the pontoon increases, the pouring thickness of the ballast concrete on the left side of the pontoon can be increased.

[0018] Preferably, the thickness of the ballast concrete in the middle of the pontoon is greater than the thickness of the ballast concrete at both ends of the pontoon.

[0019] Since the closer to the two ends of the pontoon, the greater the moment arm of the center of gravity of the ballast concrete, and the closer to the center of the pontoon, the smaller the moment arm of the center of gravity of the ballast concrete, this scheme recommends that the thickness of the prefabricated ballast weight block is larger in the middle and smaller at both ends, so that the ballast concrete is concentrated in the middle of the pontoon. This can reduce the influence of the ballast concrete on the posture of the pontoon while keeping the total mass of the ballast concrete unchanged, thereby reducing the amplitude of the change in the posture of the pontoon caused by uneven ballast concrete pouring and improving the stability of the pontoon during the ballast concrete pouring process.

[0020] Preferably, the following step is further included before step S2: a material discharge structure is provided on the pontoon every m pouring areas, m≥1, and the material discharge structure is used to transport the ballast concrete to the corresponding pouring area.

[0021] Since the pouring areas are close to each other, workers can easily transfer ballast concrete in adjacent pouring areas by means such as manual shoveling and chutes. The scheme sets up unloading structures at intervals, which can reduce the number of unloading structures, thereby reducing the modification and damage to the pontoon; and reduce the frequency of adjusting the position of the concrete delivery pipeline during subsequent pouring operations, thereby improving construction efficiency.

[0022] Preferably, the distance between the discharge port of the material discharge structure and the bottom of the casting area is less than or equal to 2 m.

[0023] This solution can avoid the situation where the ballasted concrete segregates due to excessive free fall.

[0024] Preferably, step S2 further comprises the following step: reserving an installation groove on the ballast concrete in at least one casting area, the installation groove being used for installing a prefabricated counterweight block.

[0025] This solution forms a mounting groove for the prefabricated counterweight block by ballasting concrete, which can reduce the modification and damage to the pontoon, thereby improving construction efficiency and reducing construction costs.

[0026] Preferably, in step S2, ballast concrete is poured through the ventilation duct of the pontoon.

[0027] This solution uses the existing structure on the pontoon to cast ballast concrete, which can reduce the modification and damage to the pontoon, thereby improving construction efficiency and reducing construction costs.

[0028] Preferably, in step S2, the ballast concrete is poured in layers along the height direction, and the thickness of each layer of ballast concrete is less than or equal to 20 cm.

[0029] This scheme recommends casting ballasted concrete in layers, which can improve the heat dissipation efficiency of the ballasted concrete and reduce the hydration heat peak, thereby reducing temperature cracks in the ballasted concrete and improving construction quality.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The present invention provides a construction method for ballast concrete in a pontoon. The ballast concrete is poured from the middle of the pontoon to both ends of the pontoon in a skipping manner, thereby suppressing the influence of the deadweight of the ballast concrete on the posture stability of the pontoon during the entire process of pouring the ballast concrete, thereby ensuring the posture stability of the pontoon during the pouring operation, and also suppressing the deformation of the pontoon caused by the unbalanced force inside the pontoon. After the pouring of the ballast concrete is completed, the present scheme is also assisted by prefabricated counterweight blocks to adjust the posture of the pontoon, thereby achieving precise adjustment of the posture of the pontoon. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the main cross-sectional structure of a pontoon used in a construction method of ballast concrete in a pontoon of the present invention;

[0033] Figure 2 It is a schematic diagram of the top view of the structure of a pontoon used in a construction method of ballast concrete in a pontoon of the present invention;

[0034] Figure 3 It is a top view schematic diagram of a pouring area division method adopted in a construction method of ballast concrete in a pontoon of the present invention;

[0035] Figure 4 This is a schematic diagram of the main view of the pouring area division method used in the construction method of ballast concrete in a pontoon of the present invention. Figure 1 ;

[0036] Figure 5 This is a schematic diagram of the main view of the pouring area division method used in the construction method of ballast concrete in a pontoon of the present invention. Figure 2 ;

[0037] Icons: 1- pontoon; 11- mid-tank; 12- ballast tank; 13- ventilation duct; 2- ballast concrete; 21- installation groove; 3- prefabricated ballast weight. DETAILED DESCRIPTION

[0038] The present invention is further described in detail below in conjunction with test examples and specific implementation methods. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0039] Unless otherwise specified, in the description of the specific embodiments of the present invention, the terms indicating the orientation or position relationship such as "up", "down", "left", "right", "center", "inside", "outside", etc. are all expressions based on the orientation or position relationship shown in the drawings, or the orientation or position relationship when the invented product / equipment / device is usually used. These terms of orientation or position relationship are only for the convenience of describing the scheme of the present invention or simplifying the description in the specific embodiments, so as to facilitate the technicians to quickly understand the scheme, rather than indicating or implying that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific position relationship, and therefore cannot be understood as a limitation on the present invention.

[0040] In addition, if the terms "horizontal", "vertical", "overhanging", "parallel" and the like appear, it does not mean that the corresponding devices / components / elements are required to be absolutely horizontal or vertical or overhanging or parallel, but may be slightly tilted or have deviations. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but may be slightly tilted. Alternatively, it can be simplified to mean that the corresponding devices / components / elements are set in directions such as "horizontal", "vertical", "overhanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably an error / deviation within ±8%, more preferably an error / deviation within ±6%, more preferably an error / deviation within ±5%, and more preferably an error / deviation within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the scheme of the present invention.

[0041] In addition, the expressions “first”, “second”, “third”, etc. that appear in the terms are merely descriptions used to distinguish the same or similar components and should not be understood as emphasizing or implying the relative importance of specific components.

[0042] In addition, in the description of the embodiments of the present invention, "several", "plurality" and "a number" represent at least 2. It can be any number such as 2, 3, 4, 5, 6, 7, 8, 9, and even more than 9.

[0043] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / restricted, the terms "set", "install", "connect", "connected", "provided with", "laid", and "arranged" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, and can be welding, riveting, bolting, threading, and other commonly used connection means in the field. This connection can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the internal connection of two elements.

[0044] Example 1

[0045] like Figures 1 to 5 As shown, a construction method of ballast concrete in a pontoon comprises the following steps:

[0046] S1, dividing the pontoon 1 into a plurality of casting areas along the length direction of the pontoon 1;

[0047] S2, pouring ballast concrete 2 into each pouring area, the pouring order is from the middle of the pontoon 1 to the two ends of the pontoon 1, and pouring one pouring area every n pouring areas, n ≥ 1;

[0048] S3, repeat step S2 until the pouring of ballasted concrete is completed in all pouring areas;

[0049] S4. Install a prefabricated ballast block 3, such as a metal block or a concrete block, in the pontoon 1. The prefabricated ballast block 3 is used to adjust the draft depth and posture balance of the pontoon 1.

[0050] In an optional embodiment, the pontoon 1 may be divided in step S1 by using an actual structure, such as a baffle to divide the space at the bottom of the pontoon 1 into several chambers, or no actual structure may be provided and only a template may be used for temporary division when pouring the ballast concrete 2.

[0051] In an optional embodiment, if Figure 1 As shown, the prefabricated ballast weight 3 is located in the middle tank 11 of the pontoon 1 so as to avoid being washed and corroded by the water flow in the ballast tank 12 .

[0052] In an optional embodiment, the number of the prefabricated ballast weight blocks 3 is at least two, and the prefabricated ballast weight blocks 3 are distributed at both ends of the middle cabin 11 along the length direction of the pontoon 1 .

[0053] In an optional embodiment, when pouring the ballast concrete 2 in step S2, it is also necessary to pour symmetrically relative to the centroid of the pontoon 1, so as to ensure that the forces at both ends of the pontoon 1 are balanced as much as possible; Figures 3 to 5 Taking the floating box 1 with 15 casting areas as an example, each casting area is numbered with Roman numerals Ⅰ to ⅩⅤ. The specific casting sequence can be referred to as follows:

[0054] A. Casting areas numbered VI, VIII, and X;

[0055] B. Casting areas numbered IV and XII;

[0056] C. Casting areas numbered Ⅱ and ⅩⅣ;

[0057] D. Casting areas numbered VII and IX;

[0058] E. Casting areas numbered Ⅴ and ⅩⅠ;

[0059] F. Casting areas numbered Ⅲ and ⅩⅢ;

[0060] G. Casting areas numbered Ⅰ and ⅩⅤ;

[0061] In an optional embodiment, when pouring the ballast concrete 2 in step S2, the draft and posture balance of the pontoon 1 can be adjusted by adjusting the thickness of the ballast concrete 2 in each pouring area. For example, if the draft on the left side of the pontoon 1 increases, the pouring thickness of the ballast concrete 2 on the right side of the pontoon 1 can be increased; if the draft on the right side of the pontoon 1 increases, the pouring thickness of the ballast concrete 2 on the left side of the pontoon 1 can be increased.

[0062] In an optional embodiment, the thickness of the ballast concrete 2 in the middle of the pontoon 1 is greater than the thickness of the ballast concrete 2 at both ends of the pontoon 1. Figure 5 Taking the pontoon 1 including 15 casting areas as an example, the thickness of the ballast concrete 2 in the middle, namely the ballast concrete 2 numbered V to XI, is greater than the thickness of the ballast concrete 2 numbered I to IV and XII to XV.

[0063] In an optional embodiment, the following step is further included before step S2: a material discharge structure is provided at every m pouring areas on the pontoon 1, where m≥1, and the material discharge structure is used to transport the ballast concrete 2 to the corresponding pouring area. The specific form of the material discharge structure includes but is not limited to a material discharge hole, a material discharge pipe, and a material discharge trough.

[0064] In an optional embodiment, a material unloading structure is set every other pouring area, and if the first pouring area is numbered Ⅰ, the material unloading structures are all set in even-numbered pouring areas, that is, pouring areas numbered Ⅱ, Ⅳ, Ⅵ..., so that there are pouring areas on both sides of each material unloading structure, avoiding the situation where the material unloading structure is located at the edge and only one side has a pouring area.

[0065] In an optional embodiment, the discharge structure includes a discharge hole arranged on the top of the pontoon 1, and a discharge pipe is connected to the discharge hole, and the diameter of the discharge pipe is greater than or equal to 400 mm; a discharge funnel can also be arranged at the discharge hole to assist the ballast concrete 2 to enter the hole.

[0066] In an optional embodiment, the distance between the discharge port of the material discharge structure and the bottom of the casting area is less than or equal to 2 m. For example, if the material discharge structure includes a material discharge pipe, the distance between the bottom of the material discharge pipe and the bottom of the casting area is less than or equal to 2 m.

[0067] In an optional embodiment, step S2 further includes the following step: reserving an installation groove 21 on the ballast concrete 2 in at least one casting area, and the installation groove 21 is used to install the prefabricated counterweight block 3. Figure 4 Taking the pontoon 1 shown as including 15 casting areas, and the prefabricated ballast blocks 3 are expected to be installed in casting areas numbered IV and XII as an example, the thickness of the ballast concrete 2 in the casting areas numbered IV and XII can be made lower than the thickness of the ballast concrete 2 on both sides thereof, so that the side walls of the ballast concrete 2 in the casting areas numbered III, V, XⅠ, and XⅢ can be used to form the installation groove 21.

[0068] In an optional embodiment, in step S2, ballast concrete 2 is poured through the ventilation duct 13 of the pontoon 1. Figure 1 and Figure 2 As shown, a plurality of ventilation ducts 13 are provided on the top of the pontoon 1, and the ventilation ducts 13 can be used to pour the ballast concrete 2 in the corresponding pouring area, thereby reducing the number of unloading structures and the damage of the unloading structures to the pontoon 1; however, for areas without ventilation ducts 13, it is still necessary to open holes on the top of the pontoon 1 for directly conveying the ballast concrete 2 or installing the unloading structure, and to repair the holes by welding after the ballast concrete 2 is poured.

[0069] In an optional implementation manner, in order to ensure the density of the ballast concrete 2 in each pouring area, a lower hopper may be arranged in advance in each pouring area, and a vibrating rod may be used to vibrate and compact the ballast concrete 2 during pouring.

[0070] In an optional implementation manner, the prefabricated counterweight block 3 is specifically a prefabricated concrete block.

[0071] In an optional implementation manner, the gap between the prefabricated ballast weight block 3 and the ballast concrete 2 needs to be filled to prevent the prefabricated ballast weight block 3 from sliding; dry yellow sand can be used for filling.

[0072] In an optional implementation manner, in step S2, the ballast concrete 2 is poured in layers along the height direction, and the thickness of each layer of the ballast concrete 2 is less than or equal to 20 cm.

[0073] In an optional embodiment, in step S2, the specific gravity of the ballast concrete 2 is greater than or equal to 4.3 t / m 3 .

[0074] The above are only preferred embodiments of the present invention and are 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 protection scope of the present invention.

Claims

1. A method for constructing ballast concrete in a pontoon, characterized in that: The following steps are included: S1, dividing the pontoon (1) into a plurality of casting areas along the length direction of the pontoon (1); S2, pouring ballast concrete (2) into each pouring area, the pouring order is from the middle of the pontoon (1) to the two ends of the pontoon (1), and pouring one pouring area every n pouring areas, n ≥ 1; S3, repeat step S2 until all casting areas are cast; S4. Install a prefabricated counterweight block (3) in the pontoon (1), wherein the prefabricated counterweight block (3) is used to adjust the draft depth and posture balance of the pontoon (1).

2. A method for constructing ballast concrete in a pontoon according to claim 1, characterized in that: The prefabricated counterweight block (3) is located in the middle cabin (11) of the buoyancy box (1).

3. A method for constructing ballast concrete in a pontoon according to claim 2, characterized in that: The number of the prefabricated ballast blocks (3) is at least two, and the prefabricated ballast blocks (3) are distributed at both ends of the middle cabin (11) along the length direction of the buoyancy box (1).

4. The method for constructing ballast concrete in a pontoon according to claim 1, characterized in that: Step S2 also includes the following steps: adjusting the draft and posture balance of the pontoon (1) by adjusting the thickness of the ballast concrete (2) in each casting area.

5. A method for constructing ballast concrete in a pontoon according to claim 4, characterized in that: The thickness of the ballast concrete (2) in the middle of the pontoon (1) is greater than the thickness of the ballast concrete (2) at both ends of the pontoon (1).

6. A method for constructing ballast concrete in a pontoon according to any one of claims 1 to 5, characterized in that: Before step S2, the following step is also included: a material discharge structure is arranged on the pontoon (1) at intervals of m pouring areas, m≥1, and the material discharge structure is used to transport the ballast concrete (2) to the corresponding pouring area.

7. A method for constructing ballast concrete in a pontoon according to claim 6, characterized in that: The distance between the discharge port of the material discharge structure and the bottom of the casting area is less than or equal to 2m.

8. A method for constructing ballast concrete in a pontoon according to any one of claims 1 to 5, characterized in that: Step S2 also includes the following step: reserving an installation groove (21) on the ballast concrete (2) in at least one casting area, wherein the installation groove (21) is used to install the prefabricated counterweight block (3).

9. A method for constructing ballast concrete in a pontoon according to any one of claims 1 to 5, characterized in that: In step S2, the ballast concrete (2) is poured through the ventilation duct (13) of the pontoon (1).

10. A method for constructing ballast concrete in a pontoon according to any one of claims 1 to 5, characterized in that: In step S2, the ballast concrete (2) is poured in layers along the height direction, and the thickness of each layer of the ballast concrete (2) is less than or equal to 20 cm.

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