Wharf base construction method considering load difference

Abstract

The present application belongs to the technical field of bed construction, and relates to a wharf bed construction method considering load difference, which comprises the following steps: throwing stones in a foundation trench to a large load area bed top surface to reach a preset first stone throwing elevation, and to a small load area bed top surface to reach a preset second stone throwing elevation, the preset first stone throwing elevation being higher than the preset second stone throwing elevation, and a transition area being formed between the large load area and the small load area; using a preset first tamping rate to vibrate and tamp the small load area bed; using a preset second tamping rate to vibrate and tamp the large load area bed to make it reach a preset bed leveling elevation, at this time, the large load area bed top surface elevation is higher than the small load area bed top surface elevation; using a preset gradual change tamping rate to vibrate and tamp the transition area bed; and throwing stones on the small load area and the transition area bed top surfaces and scraping them to make them reach the preset bed leveling elevation. The present application can effectively solve the problem of excessive post-construction settlement difference of the wharf bed caused by load difference.

Description

Technical Field

[0001] This invention belongs to the field of foundation construction technology, and specifically relates to a wharf foundation construction method that takes into account load differences. Background Technology

[0002] The wharf foundation is the foundation component in wharf construction, playing a supporting and stabilizing role for the wharf's superstructure. Based on the wharf's functional layout and load-bearing requirements, the wharf is typically divided into multiple zones, such as heavy-load zones and light-load zones. Therefore, after the wharf is put into operation, the load on different parts of the wharf foundation is not uniform. Based on this, the wharf foundation can be divided into high-load and low-load zones. Because the load differences between high-load and low-load zones are significant, post-construction settlement will differ between these zones, resulting in uneven settlement and differential settlement. Post-construction settlement is a core control indicator for the construction quality of the wharf foundation, directly affecting the stability and safety of the entire structure.

[0003] Currently, when constructing wharf foundation beds, the industry does not consider the impact of load differences above the foundation bed on post-construction settlement after the wharf is operational. The same foundation bed construction techniques are generally used, such as the same riprap, compaction, and leveling processes. Actual research has found that the post-construction settlement of the wharf foundation bed in the high-load area can reach 25cm, while the post-construction settlement in the low-load area is about 5cm, with a settlement difference of up to 20cm, exceeding the design requirement of 15cm settlement difference limit. This can easily lead to cracking, deformation, and misalignment of the foundation bed structure, thereby affecting the overall quality, safety, and service life of the wharf project.

[0004] In view of this, how to solve the problem of excessive post-construction settlement difference of the wharf foundation due to load differences has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] In view of the shortcomings of the related technologies, the present invention provides a wharf foundation construction method that takes into account load differences, so as to solve the technical problems mentioned in the background art.

[0006] This invention provides a method for constructing a wharf foundation that considers load differences, comprising the following steps: S1. Based on the bearing capacity of the foundation bed of the wharf to be constructed, divide the foundation bed into high load zone and low load zone; S2. Place boulders in the excavated foundation trench. Stop placing boulders when the top surface of the foundation bed in the high load area reaches the preset first boulder elevation and the top surface of the foundation bed in the low load area reaches the preset second boulder elevation. The preset first boulder elevation is higher than the preset second boulder elevation, and a naturally inclined transition zone is formed between the top of the foundation bed in the high load area and the low load area. S3. First, the subgrade in the low-load area is vibrated and compacted using a preset first compaction rate; then, the subgrade in the high-load area is vibrated and leveled using a preset second compaction rate, so that the top surface of the subgrade in the high-load area reaches the preset subgrade leveling elevation, and the elevation of the top surface of the subgrade in the high-load area after leveling is higher than the elevation of the top surface of the subgrade in the low-load area after compaction; then, the subgrade in the transition area is vibrated and compacted using a preset gradual compaction rate. S4. Pour crushed stone onto the top surface of the foundation bed in the low load area and transition area and scrape it level so that the top surface of the foundation bed in the low load area and transition area reaches the preset foundation bed leveling elevation, thereby completing the construction of the entire wharf foundation bed.

[0007] In some embodiments, in step S2, the size of the stone block is 10kg to 100kg, and the compressive strength of the stone block is greater than 50MPa.

[0008] In some embodiments, in step S3, the preset first tamping rate is set to 10%; the preset second tamping rate is set to 15%; and the preset gradual tamping rate is set to 3% for the tamping rate near the high load area and 7% for the tamping rate near the low load area.

[0009] In some embodiments, in step S3, the elevation of the top surface of the subgrade in the high-load area after compaction is 30cm to 50cm higher than the elevation of the top surface of the subgrade in the low-load area after compaction.

[0010] In some embodiments, in step S2, boulders are thrown into the foundation trench using the boulders-ramming and leveling integrated vessel; in step S3, the boulders-ramming and leveling integrated vessel is used to vibrate and level the foundation bed in the high load area and to vibrate and compact the foundation bed in the low load area and transition area; the boulders-ramming and leveling integrated vessel includes a chute boulders-ramming device and a vibratory compaction device installed on the hull.

[0011] In some embodiments, in step S4, the particle size of the crushed stone is 5 cm to 8 cm.

[0012] In some embodiments, in step S4, a bottom-sitting leveling boat is used to throw and level gravel onto the top surface of the base bed in the small load area and transition area. The bottom-sitting leveling boat includes a leveling platform vehicle located in the opening space in the middle of the hull. The upper two sides of the leveling platform vehicle are slidably connected to the hull, and the lower two sides of the leveling platform vehicle are slidably connected to a U-shaped leveling frame. The lower part of the leveling platform vehicle is provided with multiple hoppers, and a scraper is connected to the lower edge of each hopper. The bottom of the two side frames of the leveling frame that are arranged opposite each other is provided with pad beams and multiple hydraulic support legs. The pad beams extend along the length of the side frames, and multiple lifting cylinders are embedded in the top surface of the pad beams. The multiple lifting cylinders and multiple hydraulic support legs work together to provide liftable support for the leveling frame. In step S4, the bottom-mounted leveling vessel reaches the first position; the leveling frame is lowered, so that the pad beams are supported on the foundation bed in the vibratory-compacted high-load area, and multiple hydraulic outriggers are supported on the foundation bed in the compacted low-load area to be leveled; then, the leveling platform truck throws stones in stages and drives the scraper to move along the leveling frame in stages to scrape the area where the stones have been thrown, completing the foundation bed leveling operation under the current position; then, the leveling frame is lifted, the bottom-mounted leveling vessel moves to the next position, the leveling frame is lowered, so that the pad beams are supported on the foundation bed in the vibratory-compacted high-load area or the foundation bed in the compacted low-load area, and multiple hydraulic outriggers are supported on the foundation bed in the compacted low-load area to be leveled, to carry out the foundation bed leveling operation under this position, and so on to complete the foundation bed leveling operation in the low-load area and transition area.

[0013] In some embodiments, in step S4, when the bottom-sitting leveling vessel moves to the next berth, a pre-defined overlap area is formed between the levelable area corresponding to the berth and the base bed that has been leveled at the previous berth.

[0014] In some embodiments, multiple hydraulic cylinders are also embedded in the top surface of the pad beam, with the bottom and top of the hydraulic cylinders connected to the pad beam and the leveling frame, respectively. In step S4, before the pad beam is supported on the base bed or the bottom-mounted leveling vessel is moved, the lifting cylinder retracts into the pad beam, and the pulling cylinder retracts to a preset minimum stroke to press the pad beam onto the leveling frame. After the pad beam is supported on the base bed, the pulling cylinder is depressurized, and the lifting cylinder extends to lift the leveling frame.

[0015] Based on the above technical solution, the wharf foundation construction method considering load differences in this embodiment of the invention uses a vibratory tamping method with a larger settlement ratio to construct the foundation in the large load area, and a vibratory tamping method with a smaller settlement ratio plus additional crushed stone and leveling method to construct the foundation in the small load area, making the top surfaces of the foundation in the large and small load areas flush. This sets a precedent for using different construction techniques for wharf foundation construction based on different load areas, which can solve the problem of excessive post-construction settlement difference of the wharf foundation due to load differences, avoid defects such as cracking, deformation, and misalignment in the foundation structure, and thus significantly improve the overall quality, safety and service life of the wharf project. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a flowchart of the wharf foundation construction method considering load differences according to the present invention; Figure 2 This is a schematic diagram showing the result after step S2 of the present invention is completed; Figure 3 This is a schematic diagram showing the result after step S3 of the present invention is completed; Figure 4 This is a schematic diagram showing the result after step S4 of the present invention is completed; Figure 5 This is a front view of the leveled frame after it has been placed on the ground in step S4 of the present invention. Figure 6 This is a schematic diagram of the leveling frame in step S4 of the present invention; Figure 7 This is a schematic diagram of the pad beam in step S4 of the present invention; Figure 8 This is a schematic diagram of the overlapping area in step S4 of the present invention.

[0017] In the diagram: 10. Base bed; 20. Bottom-mounted leveling boat; 21. Leveling platform truck; 22. Hopper; 23. Scraper; 24. Leveling frame; 25. Side frame; 26. Pad beam; 27. Hydraulic outrigger; 28. Lifting cylinder; 29. ​​Pulling and closing cylinder; Z1. High load zone; Z2. Low load zone; Z3. Transition zone. Detailed Implementation

[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0019] In the description of this invention, it should be understood that the terms "center", "lateral", "longitudinal", "upper", "lower", "top", "bottom", "inner", "outer", "left", "right", "front", "rear", "vertical", "horizontal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0020] The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature.

[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] refer to Figures 1 to 7 As shown, the present invention provides a method for constructing a wharf foundation bed that takes into account load differences. The method includes the following steps S1 to S4.

[0023] Step S1: Based on the wharf project operation plan, identify the heavy-load area and light-load area on the wharf, thereby determining the load-bearing capacity of the wharf foundation 10 after the wharf is put into operation, and thus dividing the wharf foundation 10 into the large load area Z1 and the small load area Z2.

[0024] Step S2: Place boulders into the pre-excavated foundation trench. Stop placing boulders once the top surface of the foundation bed 10 in the high load zone Z1 reaches the preset first boulder placement elevation H1 and the top surface of the foundation bed 10 in the low load zone Z2 reaches the preset second boulder placement elevation H2. It should be noted that the preset first boulder placement elevation H1 is higher than the preset second boulder placement elevation H2, and a naturally sloping transition zone Z3 is formed between the top of the foundation bed 10 in the high load zone Z1 and the top of the foundation bed 10 in the low load zone Z2.

[0025] Specifically, the size of the stones thrown in step S2 is 10kg to 100kg, and the compressive strength of the stones is greater than 50MPa; thereby ensuring that the foundation bed 10 achieves basic functions such as bearing capacity and stability.

[0026] Step S3: First, the subgrade 10 in the small load zone Z2 is vibrated and compacted using a preset first compaction rate. The elevation of the top surface of the compacted subgrade 10 in the small load zone Z2 is recorded as H3. Then, the subgrade 10 in the large load zone Z1 is vibrated and leveled using a preset second compaction rate, so that the top surface of the subgrade 10 in the large load zone Z1 reaches the preset leveling elevation H, and the leveling elevation H of the subgrade 10 in the large load zone Z1 is higher than the top surface elevation H3 of the compacted subgrade 10 in the small load zone Z2. Specifically, the top surface elevation of the compacted subgrade 10 in the large load zone Z1 is 30cm to 50cm higher than the top surface elevation of the compacted subgrade 10 in the small load zone Z2. Then, the subgrade 10 in the transition zone Z3 is vibrated and compacted using a preset gradual compaction rate. It is understandable that step S3 is used to compact and level the base bed 10 in the large load area Z1 so that the elevation and leveling accuracy of the top surface of the base bed 10 in the large load area Z1 after vibration compaction meet the preset requirements. Step S3 also enables the compaction of the base bed 10 in the small load area Z2 and the transition area Z3, which increases the density of the base bed 10. However, there are no particularly strict requirements on the elevation and leveling accuracy of the top surface of the base bed 10 in the small load area Z2 and the transition area Z3 after vibration compaction.

[0027] To further explain, in step S3, the preset first compaction rate is set to 10%; the preset second compaction rate is set to 15%; the preset gradual compaction rate is set to 3% for the side closer to the large load zone Z1 and 7% for the side closer to the small load zone Z2. That is, the compaction rate of the transition zone Z3 gradually increases from the side closer to the large load zone Z1 to the side closer to the small load zone Z2. The number of increments of the compaction rate in the transition zone Z3 depends on the range of the transition zone Z3 and the area of ​​action of the vibratory compaction hammer. It can be understood that the compaction rate on the side closer to the large load zone Z1 in the preset gradual compaction rate is relatively small in order to avoid affecting the leveling effect of the base bed 10 in the large load zone Z1 after vibration compaction; while the compaction rate on the side closer to the small load zone Z2 in the preset gradual compaction rate is relatively large in order to ensure the compaction effect of the base bed 10 in the transition zone Z3 and the small load zone Z2.

[0028] Step S4: Crushed stones are thrown onto the top surface of the subgrade 10 in the vibratory compaction zone Z2 and transition zone Z3, and then leveled to ensure that the top surface of the subgrade 10 in the zone Z2 and transition zone Z3 reaches the preset leveling elevation H. This completes the leveling operation of the subgrade 10 in the zone Z2 and transition zone Z3. At this point, the top surface elevation of all areas of the entire subgrade 10 is consistent and meets the standard, thus completing the construction of the entire wharf subgrade 10. Specifically, the crushed stones thrown in step S4 have a particle size of 5cm to 8cm. The relatively small size of the crushed stones improves the leveling accuracy of the subgrade 10 while ensuring the strength of the subgrade 10 in the zone Z2 and transition zone Z3.

[0029] To further explain, the different compaction rates used for the subgrade 10 in different load zones in step S3 are primarily based on the varying load conditions at different locations on the subgrade 10 after the wharf's operation. Specifically, considering that under the same construction process, the post-construction settlement of the subgrade 10 in the high-load zone Z1 is significantly greater than that in the low-load zone Z2, a larger compaction rate is used for the high-load zone Z1 during subgrade 10 construction to ensure a denser subgrade 10 after compaction, thus reducing post-construction settlement in the high-load zone Z1 after the wharf's operation. Conversely, a smaller compaction rate is used for the low-load zone Z2 to increase the density of the subgrade 10 in this area. However, the density of the subgrade 10 in this area is not as high as that in the high-load zone Z1 where a larger compaction rate is used, and the compacted subgrade 10 in the low-load zone Z2... The top surface elevation of bed 10 is lower than that of bed 10 in the high load zone Z1. Therefore, in step S4, the portion of bed 10 in the low load zone Z2 that is lower than that in the high load zone Z1 is supplemented with crushed stone and leveled, so that the top surface elevation of bed 10 in different load zones is consistent after the construction of bed 10. Therefore, after the wharf is in operation, compared with bed 10 using the same construction process without considering the load bearing of bed 10, this embodiment takes into account the difference in load bearing of bed 10 and adopts different construction processes for bed 10 in different load zones, which reduces the post-construction settlement of bed 10 in the high load zone Z1 and moderately increases the post-construction settlement of bed 10 in the low load zone Z2. This can significantly reduce the difference in post-construction settlement between bed 10 in the high load zone Z1 and bed 10 in the low load zone Z2 after the wharf is in operation.

[0030] The above illustrative embodiment, under the premise of clearly defining the different load zones of the foundation bed 10 to be constructed, adopts different construction processes with different riprap elevations, different tamping rates, and different leveling methods for the high load zone Z1 and the low load zone Z2. This allows the foundation bed 10 in the high load zone Z1 to achieve the preset leveling elevation using a vibratory tamping method with a larger tamping rate, while the foundation bed 10 in the low load zone Z2 uses a vibratory tamping method with a smaller tamping rate, plus additional riprap placement and leveling, to achieve the preset leveling elevation. In other words, the construction of the wharf foundation bed 10 is achieved by using different construction processes for different load zones. This reduces the difference in post-construction settlement between the high load zone Z1 and the low load zone Z2 after the wharf is operational, solves the problem of excessive post-construction settlement difference of the wharf foundation bed 10 due to load differences, reduces uneven settlement of the foundation bed 10, and avoids defects such as cracking, deformation, and misalignment in the foundation bed 10 structure. Ultimately, this significantly improves the overall quality, safety, and service life of the wharf project.

[0031] In some embodiments, in step S2, boulders are thrown into the foundation trench using the integrated boulder-throwing and tamping vessel; in step S3, the integrated boulder-throwing and tamping vessel is used to vibrate and tampe the foundation bed 10 in the high load area Z1 and to vibrate and compact the foundation bed 10 in the low load area Z2 and the transition area Z3. Specifically, the integrated boulder-throwing and tamping vessel includes a chute-type boulder-throwing device and a vibratory compaction device installed on the hull; the chute-type boulder-throwing device includes a chute, a hopper, and a stone metering device, etc., and can overcome water flow deviation, control the thickness of the boulders, and achieve rapid boulder-throwing; the vibratory compaction device includes a vibratory hammer, a guide pipe, etc., and can perform high-frequency vibration impact on the boulders layer to increase the density of the foundation bed 10 after boulder-throwing; thus, the boulder-throwing and tamping / leveling construction of the foundation bed 10 can be realized using this integrated boulder-throwing and tamping vessel. Furthermore, the rock-throwing and compaction or leveling operations in steps S2 and S3 can be carried out simultaneously as needed. That is, it is not necessary to wait for all the rock-throwing to be completed before compaction / leveling. While moving to the next station to continue rock-throwing after completing the rock-throwing operation at the current station, the compaction / leveling operation of the rock-throwing area at the previous station can be carried out, thereby improving the construction efficiency of the wharf foundation 10.

[0032] refer to Figures 4-8 As shown, in some embodiments, in step S4, the bottom-sitting leveling boat 20 throws gravel onto the top surface of the base bed 10 in the small load area Z2 and the transition area Z3 and then scrapes it flat.

[0033] Specifically, the bottom-mounted leveling vessel 20 includes a leveling platform trolley 21 located in the open space in the middle of the hull. The leveling platform trolley 21 includes an upper platform trolley and a lower platform trolley. The upper two sides of the leveling platform trolley 21 are slidably connected to the hull, and the lower two sides of the leveling platform trolley 21 are slidably connected to a U-shaped leveling frame 24. Therefore, the leveling platform trolley 21 can move synchronously back and forth along the leveling frame 24 and the hull. The lower part of the leveling platform trolley 21, i.e., the lower platform trolley, is equipped with multiple hoppers 22, and a scraper 23 is connected to the lower edge of each hopper 22. The upper part of the leveling platform trolley 21, i.e., the upper platform trolley, is equipped with feeding hoppers that correspond one-to-one with the multiple hoppers 22. Each feeding hopper is hinged to its corresponding hopper 22 by a conveying pipe. The two side frames 25 on the leveling frame 24, which are perpendicular to the length direction of the scraper 23, are respectively provided with pad beams 26 and multiple hydraulic support legs 27 at their bottoms. The pad beams 26 extend along the length direction of the side frames 25, and multiple lifting cylinders 28 are embedded in the top surface of the pad beams 26. The multiple lifting cylinders 28 are spaced apart along the length direction of the pad beams 26. The bottom end of the lifting cylinder 28 is connected to the pad beams 26, and the top end of the lifting cylinder 28 can move up and down relative to the pad beams 26 to extend out of the pad beams 26 or retract into the pad beams 26. The multiple hydraulic support legs 27 are spaced apart along the length direction of the side frames 25, and the hydraulic support legs 27 can extend and retract up and down. Therefore, the multiple lifting cylinders 28 and the multiple hydraulic support legs 27 together provide liftable support for the leveling frame 24.

[0034] During step S4, the bottom-sitting leveling vessel 20 reaches its first position, which is roughly above the base bed 10 in the transition zone Z3. The leveling frame 24 is lowered, so that the entire pad beam 26 is supported on the top surface of the base bed 10 in the high-load zone Z1, which has been vibrated and compacted, and multiple hydraulic outriggers 27 are supported on the base bed 10 in the low-load zone Z2, which has been compacted and is to be leveled, thus achieving the bottom-sitting of the leveling frame 24. The working stroke of the lifting cylinder 28 and the hydraulic outriggers 27 is adjusted so that the elevation of the leveling frame 24 meets the preset elevation requirements. Then, the preset volume of stone material in the hopper 22 is thrown onto the base bed 10 in the low-load zone Z2 and the transition zone Z3, which has been compacted and is to be leveled. The leveling platform trolley 21 is started to drive the scraper 23 to move along the leveling frame 24 by a preset leveling stroke. During the movement, the scraper 23 pushes the stone material from the higher position to the lower position. The process involves filling in the gaps and meticulously leveling the area where gravel has been dumped, thereby creating a flat and dense leveling layer on the compacted and leveled foundation bed 10. Following this process, the platform truck 21 dumps gravel in stages and moves the scraper 23 along the leveling frame 24 in stages to level the area where gravel has been dumped, completing the leveling operation of the foundation bed 10 under the current vessel position. Then, the leveling frame 24 is lifted, the bottom-mounted leveling vessel 20 moves to the next vessel position, and the leveling frame 24 is lowered so that the pad beam 26 is supported on the foundation bed 10 in the vibratory compacted high-load area Z1 or the foundation bed 10 in the leveled low-load area Z2, and multiple hydraulic outriggers 27 are supported on the compacted and leveled low-load area Z2 foundation bed 10 to carry out the leveling operation of the foundation bed 10 under this vessel position. This process is repeated to complete the leveling operation of the foundation bed 10 in the low-load area Z2 and the transition area Z3.

[0035] The above illustrative embodiment details the specific leveling method for adding crushed stone and scraping the base bed 10 in the small load area Z2 and transition area Z3. By using the pad beam as a support device for the leveling frame 24, compared with the multi-leg, multi-point support method commonly used for the leveling frame 24, the contact area between the support device of the leveling frame 24 and the leveled base bed 10 (i.e., the base bed 10 in the large load area Z1 that has been vibrated and compacted or the base bed 10 in the small load area Z2 that has been scraped) can be significantly reduced. Therefore, the load of the support device on the leveled base bed 10 can be greatly reduced, ensuring that the top surface elevation and leveling accuracy of the leveled base bed 10 are not affected by the subsequent leveling operations of the base bed 10 and can still meet the engineering quality requirements.

[0036] refer to Figure 8As shown, in some embodiments, in step S4, when the bottom-sitting leveling boat 20 moves to the next boat position, a pre-defined overlap area is formed between the levelable area corresponding to the boat position and the base bed 10 that has been leveled in the previous boat position. This is because after the last leveling stroke of the previous boat position is completed, the last leveled base bed 10 may have some residual material accumulation or partial incompleteness of the base bed 10 due to different stone material storage in the hopper 22. By setting the overlap area, the overlap area between the two boat positions can be leveled again during the leveling operation of the base bed 10 in the next boat position, solving the problem of partial accumulation of residual material or partial incompleteness of the base bed 10 in the overlap area, and improving the construction quality of the base bed 10.

[0037] refer to Figure 7 As shown, in some embodiments, multiple pull-opening cylinders 29 are also embedded in the top surface of the pad beam 26, and the multiple pull-opening cylinders 29 are arranged at intervals along the length direction of the pad beam 26; the bottom and top of the pull-opening cylinders 29 are connected to the pad beam 26 and the leveling frame 24 respectively, while the top of the lifting cylinders 28 is not fixedly connected to the leveling frame 24. In step S4, when the leveling frame 24 moves with the bottom-sitting leveling vessel 20 or when the pad beam 26 is not yet supported on the base bed 10, the lifting cylinders 28 retract into the pad beam 26, that is, the top surface of the lifting cylinders 28 does not contact the leveling frame 24, and the pull-opening cylinders 29 retract to a preset minimum stroke so that the pad beam 26 is pressed against the leveling frame 24; thereby ensuring that there is no relative movement between the pad beam 26 and the leveling frame 24 when the leveling frame 24 moves, thereby ensuring the towing safety of the pad beam 26. After the pad beam 26 is supported on the base bed 10, the pull-close cylinder 29 is depressurized, and the lifting cylinder 28 extends to lift the leveling frame 24; when the lifting cylinder 28 extends, the pull-close cylinder 29 will also extend, but will not apply force to the leveling frame 24 or the pad beam.

[0038] Through the description of several embodiments of the wharf foundation construction method considering load differences according to the present invention, it can be seen that the present invention has at least one or more of the following advantages: 1) This invention constructs the Z1 foundation bed 10 of the large load area by using a vibratory tamping method with a larger tamping rate, and constructs the Z2 foundation bed 10 of the small load area by using a vibratory tamping method with a smaller tamping rate, plus additional crushed stone and scraping. The top surfaces of the foundation beds 10 of the large load area Z1 and the small load area Z2 are made flush. This invention sets a precedent for using different construction techniques for the construction of the wharf foundation bed 10 based on different load areas. It can solve the problem of excessive post-construction settlement difference of the wharf foundation bed 10 due to the difference in load on the foundation bed 10, and avoid defects such as cracking, deformation and misalignment of the foundation bed 10 structure. In this way, it can significantly improve the overall quality, safety and service life of the wharf project. 2) This invention utilizes a bottom-mounted leveling vessel 20 to perform supplementary crushing and leveling operations on the Z2 base bed 10 after vibration compaction in a small load area. By setting up pad beams under the leveling frame 24 on the leveling vessel, the contact area between the leveling frame 24 support device and the leveled base bed 10 is significantly increased, thereby greatly reducing the load of the support device on the leveled base bed 10. This ensures that the top elevation and leveling accuracy of the leveled base bed 10 are not affected by subsequent leveling operations and can still meet the engineering quality requirements.

[0039] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0040] The above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of the present invention or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the technical solutions claimed in the present invention.

Claims

1. A method for constructing a wharf foundation considering load differences, characterized in that, Includes the following steps: S1. Based on the bearing capacity of the foundation bed of the wharf to be constructed, divide the foundation bed into high load zone and low load zone; S2. Place boulders in the excavated foundation trench. Stop placing boulders when the top surface of the foundation bed in the high load area reaches the preset first boulder elevation and the top surface of the foundation bed in the low load area reaches the preset second boulder elevation. The preset first boulder elevation is higher than the preset second boulder elevation, and a naturally inclined transition zone is formed between the top surfaces of the foundation beds in the high load area and the low load area. S3. Vibration compaction is performed on the subgrade in the low-load area using a preset first compaction rate; then, vibration compaction is performed on the subgrade in the high-load area using a preset second compaction rate, so that the top surface of the subgrade in the high-load area reaches the preset subgrade leveling elevation, and the elevation of the top surface of the subgrade in the high-load area after compaction is higher than the elevation of the top surface of the subgrade in the low-load area after compaction; then, vibration compaction is performed on the subgrade in the transition area using a preset gradual compaction rate. S4. Pour crushed stone onto the top surface of the foundation bed in the low load area and transition area and scrape it level so that the top surface of the foundation bed in the low load area and transition area reaches the preset foundation bed leveling elevation, thereby completing the construction of the entire wharf foundation bed.

2. The wharf foundation construction method considering load differences according to claim 1, characterized in that, In step S2, the size of the stone block is 10kg to 100kg, and the compressive strength of the stone block is greater than 50MPa.

3. The wharf foundation construction method considering load differences according to claim 1, characterized in that, In step S3, the preset first compaction rate is set to 10%; the preset second compaction rate is set to 15%; and the preset gradual compaction rate is set to 3% for the side closer to the high load area and 7% for the side closer to the low load area.

4. The wharf foundation construction method considering load differences according to claim 1, characterized in that, In step S3, the elevation of the top surface of the subgrade in the high-load area after compaction is 30cm to 50cm higher than the elevation of the top surface of the subgrade in the low-load area after compaction.

5. The wharf foundation construction method considering load differences according to claim 1, characterized in that, In step S2, the rock-throwing and tamping integrated vessel is used to throw rocks into the foundation trench; in step S3, the rock-throwing and tamping integrated vessel is used to vibrate and tampe the foundation bed in the high load area and vibrate and compact the foundation bed in the low load area and transition area; the rock-throwing and tamping integrated vessel includes a chute rock-throwing device and a vibratory compaction device installed on the hull.

6. The wharf foundation construction method considering load differences according to claim 1, characterized in that, In step S4, the particle size of the crushed stone is 5cm to 8cm.

7. The wharf foundation construction method considering load differences according to claim 1, characterized in that, In step S4, crushed stones are thrown onto the top surface of the base bed in the low load area and transition area using a bottom-sitting leveling boat and then scraped flat. The bottom-sitting leveling boat includes a leveling platform vehicle located in the open space in the middle of the hull. The upper two sides of the leveling platform vehicle are slidably connected to the hull, and the lower two sides of the leveling platform vehicle are slidably connected to a U-shaped leveling frame. The lower part of the leveling platform vehicle is provided with multiple hoppers, and a scraper is connected to the lower edge of each hopper. The bottom of the two side frames of the leveling frame, which are arranged opposite each other, is provided with pad beams and multiple hydraulic support legs. The pad beams extend along the length of the side frames, and multiple lifting cylinders are embedded in the top surface of the pad beams. The multiple lifting cylinders and multiple hydraulic support legs work together to provide liftable support for the leveling frame. In step S4, the bottom-mounted leveling vessel reaches the first position and lowers the leveling frame, so that the pad beams are supported on the foundation bed in the vibratory-compacted high-load area, and multiple hydraulic outriggers are supported on the foundation bed in the compacted low-load area to be leveled. Then, the leveling platform truck throws stones in stages and drives the scraper to move along the leveling frame in stages to scrape the area where the stones have been thrown, completing the foundation bed leveling operation under the current position. Then, the leveling frame is lifted, the bottom-mounted leveling vessel moves to the next position, lowers the leveling frame, so that the pad beams are supported on the foundation bed in the vibratory-compacted high-load area or the foundation bed in the compacted low-load area, and multiple hydraulic outriggers are supported on the foundation bed in the compacted low-load area to be leveled, to carry out the foundation bed leveling operation under this position, and so on to complete the foundation bed leveling operation in the low-load area and transition area.

8. The wharf foundation construction method considering load differences according to claim 7, characterized in that, In step S4, when the bottom-sitting leveling vessel moves to the next berth, a pre-defined overlap area is formed between the levelable area corresponding to the berth and the leveled base bed of the previous berth.

9. The wharf foundation construction method considering load differences according to claim 7, characterized in that, Multiple hydraulic cylinders are also embedded in the top surface of the pad beam. The bottom and top of the hydraulic cylinders are connected to the pad beam and the leveling frame, respectively. In step S4, before the pad beam is supported on the base bed or the bottom-sitting leveling boat is moved, the lifting cylinder retracts into the pad beam, and the pulling cylinder retracts to the preset minimum stroke so that the pad beam is pressed against the leveling frame. After the pad beam is supported on the base bed, the pulling cylinder is depressurized, and the lifting cylinder extends to lift the leveling frame.

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