Construction method of breakwater caisson suitable for high and low subgrade

Abstract

This invention relates to the field of breakwater construction technology, specifically to a construction method for breakwater caissons suitable for high and low foundation beds, comprising: S1: excavating a foundation trench at a predetermined underwater location; S2: dumping rocks into the foundation trench to form a first foundation bed and a second foundation bed, the elevation of the first foundation bed being lower than that of the second foundation bed, with a step forming between the first and second foundation beds; S3: compacting the first foundation bed, installing a first caisson on the first foundation bed and ensuring the first caisson abuts against the step; S4: compacting the second foundation bed, installing a second caisson on the second foundation bed. This invention, by forming the first and second foundation beds with rocks, can raise the seabed foundation, filling the slope at the seabed drop to form a step, and then installing the first and second caissons respectively on the first and second foundation beds for caisson foundation construction. The elevation of the rocks dumped on both high and low foundation beds can be controlled, avoiding the difficulty in controlling the elevation caused by using pad blocks to support the caisson.

Description

Technical Field

[0001] This invention relates to the field of breakwater construction technology, and in particular to a construction method for breakwater caissons suitable for high and low foundation beds. Background Technology

[0002] In the existing construction of breakwaters, if caissons are used as the foundation, the installation of the caissons is usually carried out sequentially from the base to the head of the breakwater. However, the seabed geological conditions are complex, the seabed foundation is uneven with height differences and slopes at the height differences. If the traditional construction method from the base to the head of the breakwater is followed, pad blocks need to be set up on the slopes to support the caissons. This requires manual assistance, is time-consuming and labor-intensive, the elevation is difficult to control, the construction period is long, and it is difficult to complete the construction during the typhoon window. Summary of the Invention

[0003] The purpose of this invention is to overcome the technical problems in the prior art where the installation of breakwater caissons from the base to the head of the breakwater requires manual support blocks, resulting in low construction efficiency and difficulty in controlling the elevation. The invention provides a construction method for breakwater caissons suitable for both high and low foundation beds.

[0004] This invention provides a construction method for breakwater caissons suitable for high and low foundation beds, comprising: S1: excavating a foundation trench at a predetermined underwater location; S2: dumping stones into the foundation trench to form a first foundation bed and a second foundation bed, wherein the elevation of the first foundation bed is lower than that of the second foundation bed, and a step is formed between the first foundation bed and the second foundation bed; S3: compacting the first foundation bed, installing a first caisson on the first foundation bed and ensuring that the first caisson abuts against the step; S4: compacting the second foundation bed, and installing a second caisson on the second foundation bed.

[0005] This application employs a method of creating a high-low foundation bed by dumping rocks on the seabed as the basis for caisson installation. First, rocks are dumped in the trench to form a first foundation bed (low foundation bed) and a second foundation bed (high foundation bed). The first foundation bed is then compacted, and the first caisson is installed at the step between the high and low foundation beds on the first foundation bed. After the first caisson at the step is installed, the second foundation bed is compacted, and then the second caisson is installed, until all caissons are installed. By creating the first and second foundation beds through rock dumping, the seabed foundation can be raised, and the slope at the seabed drop can be filled to form a step. The first and second caissons are then installed on the first and second foundation beds respectively for caisson foundation construction. The elevation of the rocks dumped on both the high and low foundation beds can be controlled, avoiding the problem of uncontrollable elevation when using pad blocks to support the caissons. Furthermore, installing the first caisson at the step before compacting the second foundation bed prevents the rocks on the second foundation bed from shifting laterally under pressure and affecting the elevation of the first foundation bed. In other words, the first caisson at the step can limit the movement of the second foundation bed.

[0006] Preferably, forming the first base bed includes: A1: throwing stones into the base trench to form the bottom layer of the first base bed; A2: compacting the bottom layer of the first base bed; A3: throwing stones above the bottom layer of the first base bed to form the surface layer of the first base bed; A4: compacting the surface layer of the first base bed.

[0007] The low foundation bed can be divided into upper and lower layers, and riprap and compaction operations can be carried out in sequence to improve the compactness of the foundation bed. After the caisson is installed on the foundation bed, the displacement deviation caused by the settlement of the caisson can be reduced.

[0008] Preferably, the stone particle size forming the bottom layer of the first base bed is larger than the stone particle size forming the top layer of the first base bed.

[0009] For the upper and lower layers of the foundation bed, large-diameter stones can be selected as the riprap material for the lower layer, for example, stones weighing 10-500 kg. Smaller-diameter stones can be selected as the riprap material for the upper layer, for example, stones weighing 10-100 kg. Placing large stones in the lower layer and small stones in the upper layer ensures that the foundation bed reaches a sufficient elevation while maintaining sufficient compactness, thus providing adequate support for the caisson above and minimizing the risk of caisson settlement.

[0010] Preferably, forming the second base bed includes: B1: throwing stones into the base trench to form the bottom layer of the second base bed; B2: compacting the bottom layer of the second base bed; B3: throwing stones above the bottom layer of the second base bed to form the surface layer of the second base bed; B4: compacting the surface layer of the second base bed.

[0011] Similarly, for high foundation beds, rock-filling and compaction operations can be carried out in two layers, one above the other, to improve the compactness of the foundation bed. After the caisson is installed on the foundation bed, the displacement deviation caused by the settlement of the caisson can be reduced.

[0012] Preferably, the stone particle size of the bottom layer forming the second base bed is larger than the stone particle size of the top layer forming the second base bed.

[0013] Similarly, for the upper and lower two-layer structure of a high subgrade, large-diameter stones can be selected as the riprap material for the lower layer, for example, stones weighing 10-500 kg. Smaller-diameter stones can be selected as the riprap material for the upper layer, for example, stones weighing 10-100 kg. Placing large stones in the lower layer and small stones in the upper layer ensures that the subgrade reaches a sufficient elevation while maintaining sufficient compactness, thus providing adequate support for the caisson above and minimizing the risk of caisson settlement.

[0014] Preferably, the difference between the elevation of the second base bed and the elevation of the first base bed is equal to the difference between the height of the first caisson and the height of the second caisson.

[0015] When setting the height difference between the high and low foundation beds and the prefabricated caissons, the elevation difference between the high and low foundation beds can be kept consistent with the height difference between the two types of caissons. After the caissons are installed, the top elevation of the two types of caissons can be guaranteed to be consistent. In other words, the top of each caisson is located on the same horizontal plane, which is beneficial to the subsequent construction of the breast wall above the caisson.

[0016] Preferably, an installation joint is reserved between adjacent first caissons, adjacent second caissons, and between the first caisson and the second caisson; the construction method further includes measuring the width of the installation joint.

[0017] During construction, an installation joint must be reserved between adjacent caissons to prevent the installation joint from being too small after the installation of two adjacent high and low foundation caissons, which would prevent the high foundation caisson from being installed. During construction, the distance between the two high and low foundation caissons is measured daily, and settlement displacement is monitored to determine if the installation length of the high foundation caisson is sufficient. If not, the low foundation caisson that has shifted must be adjusted promptly.

[0018] Preferably, the top elevation of the first base bed is greater than or equal to the bottom elevation of the second base bed.

[0019] The top elevation of the first foundation bed formed after riprap placement is higher than the bottom elevation of the second foundation bed, which can keep the elevation difference between the first and second foundation beds within a small range and reduce the impact of the second foundation bed on the installed first caisson during the compaction process.

[0020] Preferably, the first caisson is installed sequentially along the length of the first base bed from the step.

[0021] Install the first caisson sequentially from the steps to control the width of the installation gap between the caissons.

[0022] Preferably, the first base bed is located at both ends of the second base bed, and the second caisson is installed from both ends of the second base bed along the length of the second base bed toward the middle of the second base bed.

[0023] If the low foundation bed is located at both ends of the high foundation bed, the second caisson can be installed from both ends toward the middle. This allows for simultaneous construction from both ends, improving construction efficiency and making it easier to control the width of the installation joint between the caissons. Consequently, the length of the installation space for the last caisson can be controlled, ensuring that the last caisson has sufficient space for installation.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] This invention provides a construction method for breakwater caissons suitable for use with high and low foundation beds. The method involves creating high and low foundation beds by scattering rocks on the seabed, which serve as the base for caisson installation. First, rocks are scattered in a foundation trench to form a first foundation bed (low foundation bed) and a second foundation bed (high foundation bed). The first foundation bed is then compacted, and the first caisson is installed at the step between the high and low foundation beds on the first foundation bed. After the first caisson at the step is installed, the second foundation bed is compacted, and then the second caisson is installed on the second foundation bed, until all caissons are installed. The method of creating the first and second foundation beds by scattering rocks raises the seabed foundation, allowing for... The slope at the seabed drop is filled to form steps, and then the first and second caissons are installed on the first and second foundation beds respectively to carry out the construction of the caisson foundation. The elevation of the riprap on both the high and low foundation beds can be controlled, avoiding the problem of difficulty in controlling the elevation caused by using pad blocks to support the caissons. Furthermore, installing the first caisson at the step before compacting the second foundation bed can prevent the stones on the second foundation bed from shifting laterally under pressure and falling onto the first foundation bed, thus affecting the elevation of the first foundation bed. In other words, the first caisson at the step can limit the movement of the second foundation bed. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of high and low foundation beds.

[0027] Figure 2 This is a schematic diagram of the low-bed cross-section.

[0028] Figure 3 This is a schematic diagram of the cross-section of the high-bed subgrade.

[0029] Figure 4 This is a schematic diagram of the installation of the first caisson at the step of the high and low foundation.

[0030] Figure 5 A schematic diagram showing the completed installation of the caisson on the high and low foundation beds.

[0031] Marked in the image:

[0032] 1. First base bed; 11. Bottom layer; 12. Surface layer; 2. Second base bed; 21. Bottom layer; 22. Surface layer; 3. First caisson; 4. Second caisson; 5. Installation joint; 6. Foundation trench. Detailed Implementation

[0033] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0034] Unless otherwise specified, the use of terms such as "upper," "lower," "left," "right," "center," "inner," and "outer" to indicate orientation or positional relationships in the description of specific embodiments of the present invention is based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is typically placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0035] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," and "parallel" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, or parallel, but rather that it can be slightly tilted or have a deviation. For example, "horizontal" merely means that its direction is more horizontal relative to "vertical," not that the structure must be completely horizontal, but that it can be slightly tilted. Alternatively, it can be simplified to mean that the corresponding device / component / element, when set in a "horizontal," "vertical," "suspended," or "parallel" direction, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the present invention.

[0036] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0037] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as 2, 3, 4, 5, 6, 7, 8, or 9, and can even exceed nine.

[0038] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to common connection methods in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0039] Example

[0040] This embodiment provides a construction method for breakwater caissons suitable for both high and low foundation beds.

[0041] Figure 1 A schematic diagram of high and low foundation beds; Figure 2 This is a schematic diagram of the low-bed cross-section; Figure 3 This is a schematic diagram of the cross-section of the high-bed subgrade; Figure 4 This is a schematic diagram of the installation of the first caisson at the step of the high and low foundation bed; Figure 5 A schematic diagram showing the completed installation of the caisson on the high and low foundation beds.

[0042] like Figures 1 to 5 As shown in the figure, the construction steps of the breakwater caisson construction method applicable to high and low foundation beds described in this embodiment are as follows:

[0043] S1: First, excavate trench 6 on the seabed. Trench 6 can be excavated along the length of the breakwater. There are transitional slopes between the two sides of trench 6 and the seabed. Its cross-sectional structure can be in the shape of an inverted trapezoid.

[0044] S2: The foundation surface in the excavated foundation trench 6 can be divided into a low foundation surface and a high foundation surface according to different elevations. Stones can be thrown into the foundation trench 6 using a stone-throwing boat. Specifically, stones can be thrown on the low foundation surface to form the first foundation bed 1, and stones can be thrown on the high foundation surface to form the second foundation bed 2, so that the elevation of the first foundation bed 1 is lower than the elevation of the second foundation bed 2. That is to say, the first foundation bed 1 can be used as the low foundation bed, and the second foundation bed 2 can be used as the high foundation bed, and a step is formed at the junction between the first foundation bed 1 and the second foundation bed 2.

[0045] S3: The first base bed 1 can be compacted using tools such as a rammer to bring it to the preset elevation. The first caisson 3 can be installed on the first base bed 1. The first caisson 3 can be installed at the junction of the first base bed 1 and the second base bed 2 so that the first caisson 3 abuts against the step.

[0046] S4: After the first caisson 3 is installed, the second base bed 2 can be compacted using tools such as a rammer to bring the second base bed 2 to the preset elevation. The second caisson 4 is then installed on the second base bed 2 until all caissons are installed.

[0047] Specifically, for example, there are a total of 35 caissons (first caisson 3 and second caisson 4) to be installed, numbered from the base of the breakwater towards the head as 1#, 2#, 3#, 34#, and 35#. Among them, caissons 1# to 6# and 30# to 35# are first caissons (3), i.e., low-bed caissons, and caissons 7# to 29# are second caissons (4), i.e., high-bed caissons. Caissons 1# to 6# and 30# to 35# are installed on the first foundation bed 1, and caissons 7# to 29# are installed on the second foundation bed 2. After the first foundation bed 1 is compacted and shaped, caissons 6# and 30# can be installed first at the junction of the second foundation bed 2 and the two first foundation beds 1 at both ends. Then the second foundation bed 2 is compacted and shaped, and caissons 7# to 29# are installed on the second foundation bed 2. Finally, caissons 1# to 5# and 31# to 35# are installed.

[0048] Here, after the first foundation bed 1 is compacted and formed, caissons #6 and #30 are installed first. These caissons can hold the step at the junction of the second foundation bed 2 and the first foundation bed 1. Then, the second foundation bed 2 is compacted. This prevents the stones on the second foundation bed 2 from shifting laterally under pressure and falling onto the first foundation bed 1, thus affecting the elevation of the first foundation bed 1. In other words, caissons #6 and #30 can limit the movement of the second foundation bed 2. Of course, caissons #1 to #6 and #30 to #35 can also be installed first, then the second foundation bed 2 can be compacted, and caissons #7 to #29 can be installed.

[0049] In this embodiment, the specific steps of the method for compacting and shaping the first base bed 1 and the second base bed 2 are as follows:

[0050] The steps for forming the first substrate bed 1 are as follows:

[0051] A1: Stones are thrown into the formation position of the first base bed 1 in the foundation trench 6 to serve as the bottom layer 11 of the first base bed 1;

[0052] A2: Use tools such as tampers to compact the bottom layer 11 of the first foundation bed 1;

[0053] A3: Stones are thrown above the bottom layer 11 of the first base bed 1 to form the surface layer 12 of the first base bed 1;

[0054] A4: Use tools such as tampers to compact the surface layer 12 of the first base bed 1.

[0055] The steps for forming the second substrate bed 2:

[0056] B1: Stones are thrown into the formation position of the second base bed 2 in the foundation trench 6 as the bottom layer 21 of the second base bed 2;

[0057] B2: Use tools such as tampers to compact the bottom layer 21 of the second base bed 2;

[0058] B3: Stones are thrown above the bottom layer 11 of the second base bed 2 to form the surface layer 22 of the second base bed 2;

[0059] B4: Use tools such as tampers to compact the surface layer 22 of the second base bed 2.

[0060] Here, the low foundation bed can be divided into upper and lower layers for riprap placement and compaction, which can improve the compactness of the foundation bed. After the caisson is installed on the foundation bed, the displacement deviation caused by the settlement of the caisson can be reduced.

[0061] For the upper and lower layers of the foundation bed, large-diameter stones can be selected as the riprap material for the bottom layer 11 and bottom layer 21, for example, stones weighing 10-500 kg can be used. Relatively smaller-diameter stones can be selected as the riprap material for the top layer 12 and top layer 22, for example, stones weighing 10-100 kg can be used. Placing large stones in the bottom layers 11 and 21 and smaller stones in the top layers 12 and 22 ensures that the foundation bed reaches a sufficient elevation while maintaining sufficient compactness, thus providing adequate support for the caisson above and minimizing the risk of caisson settlement.

[0062] In this embodiment, the difference between the elevation of the second foundation bed 2 and the elevation of the first foundation bed 1 is equal to the difference between the height of the first caisson 3 and the height of the second caisson 4. By setting the height difference between the high and low foundation beds and the prefabricated caissons, the elevation difference between the high and low foundation beds can be kept consistent with the height difference between the two types of caissons. After the caissons are installed, it can be ensured that the top elevations of the two types of caissons are consistent, meaning that the top of each caisson is located on the same horizontal plane, which is beneficial for the subsequent construction of the breast wall above the caissons.

[0063] For example, the elevation of the first foundation bed 1 is -18m, and the elevation of the second foundation bed 2 is -14m, a difference of 4m. The height of caissons #1 to #6 and #30 to #35 can be 10m, and the height of caissons #7 to #29 can be 6m, also a difference of 4m. After all caissons are installed on the foundation beds, the tops of all caissons can be aligned on the same horizontal plane. Of course, the specific elevation data of the foundation beds and the height data of the caissons can be arbitrarily selected, as long as it is ensured that the top elevation of the caissons is consistent after installation. This invention does not impose specific limitations on this.

[0064] In this embodiment, an installation joint 5 is reserved between any two adjacent caissons; the construction method may further include measuring the width of the installation joint 5. During construction, an installation joint 5 must be reserved between adjacent caissons to prevent the installation joint 5 from being too small after the installation of two adjacent high and low foundation caissons, thus preventing the high foundation caisson from being unable to be installed. During construction, the distance between the two high and low foundation caissons is measured daily, and settlement displacement is observed to determine whether the installation length of the high foundation caisson is met. If not, the low foundation caisson that has shifted must be adjusted promptly.

[0065] Optionally, the top elevation of the first foundation bed 1 is greater than or equal to the bottom elevation of the second foundation bed 2. Having the top elevation of the first foundation bed 1, formed after riprap placement, higher than the bottom elevation of the second foundation bed 2 can control the elevation difference between the two foundation beds within a smaller range, thus reducing the impact of the second foundation bed 2 on the already installed first caisson 3 during compaction. If the elevation difference between the first foundation bed 1 and the second foundation bed 2 is too large, the second foundation bed 2 may generate a large lateral force on the first caisson 3 during compaction, causing the first caisson 3 to shift.

[0066] In this embodiment, the first caisson 3 is installed sequentially along the length of the first base bed 1 from the step. Installing the first caisson 3 sequentially from the step facilitates control of the width of the installation gap 5 between the caissons.

[0067] In this embodiment, the first base bed 1 is located at both ends of the second base bed 2, and the second caisson 4 is installed from both ends of the second base bed 2 along the length of the second base bed 2 toward the middle of the second base bed 2.

[0068] If the low foundation bed is located at both ends of the high foundation bed, the second caisson 4 can be installed from both ends toward the middle. This allows for simultaneous construction from both ends, improving construction efficiency and making it easier to control the width of the installation joint 5 between the caissons. Consequently, the length of the installation space for the last caisson can be controlled, ensuring that the last caisson has sufficient space for installation.

[0069] In summary, this invention uses a rock-filled foundation to create a series of different levels of seabed for caisson installation. First, rocks are placed in a trench to form a first (low) and a second (high) foundation. The first foundation is then compacted, and the first caisson is installed at the step between the high and low foundations. After the first caisson is installed at the step, the second foundation is compacted, and the second caisson is installed, until all caissons are installed. The rock-filled foundation raises the seabed base, allowing for the filling of slopes at seabed elevations to form steps. The first and second caissons are then installed on the first and second foundations respectively for caisson foundation construction. The rock-filled elevations of both the high and low foundations can be controlled, avoiding the elevation control issues associated with using pad blocks to support the caissons. Furthermore, installing the first caisson at the step before compacting the second foundation prevents the rocks on the second foundation from shifting laterally under pressure and affecting the elevation of the first foundation. In other words, the first caisson at the step can limit the movement of the second foundation.

[0070] 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 within the protection scope of the present invention.

Claims

1. A construction method for breakwater caissons suitable for high and low foundation beds, characterized in that, include: S1: Excavate a trench at a predetermined underwater location (6); S2: Stones are thrown into the trench (6) to form a first base bed (1) and a second base bed (2) in succession. The elevation of the first base bed (1) is lower than that of the second base bed (2). A step is formed between the first base bed (1) and the second base bed (2). S3: Tamp the first base bed (1), install the first caisson (3) on the first base bed (1) and make the first caisson (3) abut against the step; S4: Compact the second base bed (2), and install the second caisson (4) on the second base bed (2); The difference between the elevation of the second base bed (2) and the elevation of the first base bed (1) is equal to the difference between the height of the first caisson (3) and the height of the second caisson (4); The first caisson (3) is installed sequentially along the length of the first base bed (1) from the step; The first base bed (1) is located at both ends of the second base bed (2), and the second caisson (4) is installed from both ends of the second base bed (2) along the length of the second base bed (2) toward the middle of the second base bed (2).

2. The construction method for breakwater caissons applicable to high and low foundation beds according to claim 1, characterized in that, Forming the first substrate (1) includes: A1: Throw stones into the trench (6) to form the bottom layer (11) of the first base bed (1); A2: Strengthen the bottom layer (11) of the first base bed (1); A3: A surface layer (12) of the first base bed (1) is formed by scattering stones above the bottom layer (11) of the first base bed (1). A4: Compact the surface layer (12) of the first base bed (1).

3. The construction method for breakwater caissons applicable to high and low foundation beds according to claim 2, characterized in that, The stone particle size of the bottom layer (11) forming the first base bed (1) is larger than the stone particle size of the surface layer (12) forming the first base bed (1).

4. The construction method for breakwater caissons applicable to high and low foundation beds according to claim 1, characterized in that, Forming the second substrate (2) includes: B1: Throw stones into the foundation trench (6) to form the bottom layer (21) of the second foundation bed (2); B2: Strengthen the bottom layer (21) of the second base bed (2); B3: A surface layer (22) of the second base bed (2) is formed by scattering stones above the bottom layer (21) of the second base bed (2); B4: Compact the surface layer (22) of the second base bed (2).

5. The construction method for breakwater caissons applicable to high and low foundation beds according to claim 4, characterized in that, The stone particle size of the bottom layer (21) forming the second base bed (2) is larger than the stone particle size of the surface layer (22) forming the second base bed (2).

6. The construction method for breakwater caissons applicable to high and low foundation beds according to claim 1, characterized in that, An installation joint (5) is reserved between adjacent first caissons (3), adjacent second caissons (4), and between first caissons (3) and second caissons (4); the construction method also includes measuring the width of the installation joint (5).

7. The construction method for breakwater caissons applicable to high and low foundation beds according to claim 1, characterized in that, The top elevation of the first base bed (1) is greater than or equal to the bottom elevation of the second base bed (2).

Images