Wind power construction hoisting platform suitable for breakwater

Abstract

The utility model discloses a wind power construction hoisting platform suitable for a breakwater. The wind power construction hoisting platform comprises a block stone platform, a PHC tubular pile group, a hill-skill soil layer and a roadbed plate group, the block stone platform is formed by filling the edge of a breakwater body of the breakwater with block stones; the PHC pipe pile group consists of a plurality of PHC pipe piles, is vertically inserted into the block stone layer and the stratum below the block stone layer, and is distributed below two crawler belts of the crawler crane so as to bear all loads of the crawler crane; the PHC pipe pile and the pile hole are reinforced through a cement mortar layer, and after an upper soil layer is laid on the top for leveling, a roadbed plate is laid to form a crawler crane working face; the wind power construction hoisting platform is good in foundation reinforcement treatment effect, safe and reliable; and the platform construction method is simple and convenient, the operation cost is low, the construction period is short, and the platform can be used as a later operation maintenance platform after fan construction is completed.

Description

Technical Field

[0001] This utility model relates to the field of foundation reinforcement technology for hoisting platforms in onshore wind power engineering, and in particular to a wind power construction hoisting platform suitable for breakwaters. Background Technology

[0002] Traditional onshore wind power is located in inland areas. The cranes used for wind turbine installation typically only need to be leveled and have roadbed slabs erected, without the need for deep foundation reinforcement, to meet the needs of the installation operation. However, with the geographical expansion of onshore wind power projects, wind power facility construction is gradually extending to the boundary areas between onshore and offshore, such as port breakwaters, which are tidal zones.

[0003] Currently, wind power construction techniques are mostly geared towards offshore or onshore wind power, while wind power technologies applied to tidal zone environments such as breakwaters remain largely undeveloped, lacking readily available project case studies and construction standards. Although breakwater construction falls under the category of land-based construction, breakwaters are essentially underwater structures built to block the impact of waves, protect harbor basins, maintain water surface stability to protect ports from adverse weather conditions, and facilitate the safe berthing and operation of ships. These environments not only have low soil bearing capacity but also narrow breakwater crests, resulting in limited working surfaces for wind power construction, insufficient to meet the requirements for crane-assisted wind turbine installation.

[0004] According to the initial construction plan, simply constructing a temporary rubble platform on the breakwater slope as a hoisting platform would present significant challenges in foundation reinforcement. Furthermore, the breakwater slope is composed of years of siltation, and the rubble backfilling would easily create a slip surface in the silt layer. The maximum load of the crane, counterweight, and pneumatic components during hoisting operations would reach thousands of tons, requiring a high bearing capacity for the hoisting platform. Foundation bearing capacity calculations showed that the platform's capacity was insufficient for hoisting operations. Moreover, the large size and irregular shape of the rubble used in the temporary platform meant that conventional reinforcement measures such as surcharge, dynamic compaction, and grouting would not achieve effective reinforcement.

[0005] Therefore, considering the geological conditions of breakwaters, it is necessary to develop and design a hoisting platform suitable for wind power construction in open sea breakwater environments to achieve safe, reliable, high-quality, and efficient construction. Utility Model Content

[0006] The purpose of this invention is to provide a wind power construction hoisting platform suitable for breakwaters that solves the above-mentioned technical problems.

[0007] Therefore, the technical solution of this utility model is as follows:

[0008] A wind power construction hoisting platform suitable for breakwaters includes a riprap platform, PHC pipe pile assemblies, a soil layer, and a roadbed slab assembly; wherein,

[0009] A riprap platform is a layer of riprap formed by filling the edge of the breakwater with several riprap stones, and the top surface of the riprap layer should be lower than the top surface of the breakwater.

[0010] The PHC pipe pile group consists of several PHC pipe piles, which are vertically inserted into the boulders layer and the underlying strata, and are adapted to the maximum load under the hoisting operation conditions. The several PHC pipe piles are divided into two groups and are respectively arranged below the designed station positions of the crawler tracks on both sides of the crawler crane. The multiple PHC pipe piles in each group are evenly distributed in multiple rows along the length of the crawler track, and the number of PHC pipe piles in each row is at least two. The number of PHC pipe piles in the end rows is more than the number of PHC pipe piles in the middle rows.

[0011] The topsoil layer is formed by laying topsoil on the top surface of the rubble platform, and the top surface of the topsoil layer and the top surface of each PHC pipe pile are flush with the top surface of the breakwater.

[0012] The roadbed layer is formed by multiple roadbed plates, which are divided into two groups to form the direct working surfaces of the crawler crane's tracks on both sides. The multiple roadbed plates in each group are arranged along the width of the track and laid horizontally on the topsoil layer above a group of PHC pipe piles. The multiple rows of PHC pipe piles correspond one-to-one with the multiple roadbed plates and are arranged in the center below the corresponding roadbed plates.

[0013] Furthermore, the boulders used to fill the boulders platform are granite blocks weighing 10 kg / block to 50 kg / block.

[0014] Furthermore, PHC pipe piles are inserted into the boulders layer and the underlying strata by drilling down-the-holes in the boulders layer.

[0015] Furthermore, a layer of cement mortar is filled and cured in the annular gap between each PHC pipe pile and the corresponding downhole pilot section.

[0016] Furthermore, for multiple PHC pipe piles in each group, the center-to-center distance between the two PHC pipe piles in the end row is greater than the width of the track; the center-to-center distance between the two PHC pipe piles in the middle row is the same as the width of the track.

[0017] Furthermore, the PHC pipe piles are PHC pipe piles with a closed pile tip at the bottom.

[0018] Furthermore, the height of the topsoil layer is generally set to 8cm~12cm.

[0019] Compared with existing technologies, this wind power construction hoisting platform suitable for breakwaters fully considers the load-bearing instability of temporary riprap platforms. It forms the platform base by filling riprap platforms, with several PHC pipe piles bearing the entire load of the crawler crane. After leveling the top layer of soil, a roadbed plate is laid on the top layer to form the crawler crane's working surface, pioneering a new method for foundation reinforcement treatment of hoisting platforms at breakwaters. This wind power construction hoisting platform not only has good foundation reinforcement effect and safety and reliability, but also has a simple and convenient construction method, low operating cost, and a short construction cycle of 4-6 days. After the wind turbine construction is completed, it can also be used as a later operation and maintenance platform for daily maintenance, upkeep, and inspection, thus having a dual purpose and relatively reducing subsequent maintenance costs. Attached Figure Description

[0020] Figure 1 This is a side view of a wind power construction hoisting platform applicable to breakwaters in an embodiment of this utility model;

[0021] Figure 2 This is a top view of the wind power construction hoisting platform applicable to breakwaters in this utility model embodiment, in an actual construction scenario.

[0022] Figure 3 This is a schematic diagram illustrating the setup of observation points during a load test of a wind power construction hoisting platform suitable for breakwaters, as described in this utility model embodiment. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the following embodiments are by no means intended to limit the present invention.

[0024] This embodiment uses the Tianjin Dongjiang North Breakwater Wind Power Project as an example to describe in detail the new type of wind power construction hoisting platform suitable for breakwaters and its supporting construction operation method. In this embodiment, the Tianjin Dongjiang North Breakwater Wind Power Project is the first wind power project in China to be constructed on a riprap sloping breakwater.

[0025] Preliminary surveys for the project indicate that the maximum total load of the crane, counterweight, and wind turbine components during wind power installation operations is 1346 tons, which translates to a ground bearing capacity of 19.6 t / m² for the installation platform. 2Only by meeting the requirements of wind turbine construction operations can the riprap slope be adequately constructed. However, the top width of the riprap slope is only 6m, leaving a small space for wind turbine hoisting operations. The breakwater slope is composed of silt that has been backfilled over many years, and after the riprap is used to squeeze the silt backfill, the silt layer is prone to forming a slip surface. Using a simple temporary riprap platform on the breakwater slope as a hoisting platform is not feasible because the riprap is large and irregularly shaped, making foundation reinforcement difficult. Conventional methods such as surcharge, dynamic compaction, and grouting reinforcement have not been calculated to achieve the required reinforcement effect. Therefore, the required working area and foundation bearing capacity for wind turbine hoisting crane operations cannot be met.

[0026] Based on this, in order to meet construction requirements, compensate for the environmental defects of the breakwater itself, and enable the construction hoisting platform to support the hoisting operations of the crawler crane 7 and temporarily place wind turbine structural components, this utility model designs and constructs a... Figure 1 and Figure 2 The wind power construction hoisting platform shown is suitable for breakwaters and specifically includes a riprap platform 1, a PHC pipe pile assembly, a hillside soil layer 5, and a roadbed plate assembly.

[0027] The riprap platform 1 serves as the structural foundation for the wind power construction hoisting platform. It consists of a layer of riprap formed by filling the edge of the breakwater 9 with several riprap blocks. The slope of the riprap layer is naturally sloping, and the top surface is initially flat and slightly lower than the top surface of the breakwater 9. The riprap blocks used to fill the riprap platform 1 can be, but are not limited to, granite blocks with a size of 10 kg / block to 50 kg / block. The location and top surface dimensions of the riprap platform 1 are consistent with the planned location and platform surface dimensions of the wind power construction hoisting platform, and it is located adjacent to the wind power platform 8 used for constructing the wind turbine facility 10.

[0028] The PHC pipe pile assembly consists of several PHC pipe piles 2, which are divided into two groups and respectively arranged below the designed station positions on both sides of the track. Each group of multiple PHC pipe piles 2 is evenly distributed in multiple rows along the length of the track from its front end to its rear end, so as to achieve even support below the corresponding track station positions. Each row contains at least two PHC pipe piles 2, with more PHC pipe piles 2 in the end rows than in the middle rows, to balance the eccentric force during the operation of the crawler crane 7. Preferably, for each group of multiple PHC pipe piles 2, in the end rows, the center-to-center distance between the two end PHC pipe piles 2 is greater than the width of the track 7b; in the middle rows, the center-to-center distance between the two end PHC pipe piles 2 is the same as the width of the track 7b.

[0029] In terms of size design, the dimensions and quantity of PHC pipe piles 2 are adapted to the maximum load under hoisting operation conditions to ensure that the bearing capacity of the wind power construction hoisting platform meets the hoisting operation requirements. The PHC pipe piles 2 are vertically inserted, and their length meets the following requirements: the lower part of the PHC pipe pile 2 is vertically inserted into the silt layer 11, and the upper part is inserted into the rubble layer of the rubble platform 1, and the top elevation of the pile is flush with the top surface of the breakwater 9. Among them, PHC pipe piles 2 preferably adopt PHC pipe piles with a closed pile tip 3 at the bottom end to improve the vertical compressive bearing capacity of the pipe pile.

[0030] In this embodiment, the crawler crane 7 is a 900t crane, including a crane body 7a and two tracks 7b. Correspondingly, 24 PHC pipe piles 2 are arranged below it. Each group of 12 PHC pipe piles 2 are evenly distributed in five rows along the length of the track, and the spacing between adjacent rows of PHC pipe piles 2 is 2400mm. Among them, there are three PHC pipe piles 2 in the end rows at both ends, and the spacing between adjacent PHC pipe piles 2 is 1065mm. There are two PHC pipe piles 2 in the middle three rows, and the spacing between them is 1500mm. Each PHC pipe pile 2 is 500mm in diameter, 100mm in wall thickness, and 33m in length. The bottom end of the PHC pipe pile 2 is provided with a closed pile tip 3.

[0031] PHC pipe piles 2 are driven by drilling down-the-holes on the boulders platform 1. This results in a pilot hole section on the top side of each down-the-hole, and the diameter of the pilot hole section is larger than the diameter of the PHC pipe pile 2. In order to further reinforce the structure formed by the boulders platform 1 and several PHC pipe piles 2, a cement mortar layer 4 is filled in the annular gap between each PHC pipe pile 2 and the pilot hole section of the corresponding down-the-hole, so as to prevent the PHC pipe piles from moving or deviating during hoisting and to improve the bearing capacity of the PHC pipe pile group.

[0032] In this embodiment, the cement mortar layer is formed using M10 cement mortar, and the amount of cement mortar used is considered to have a filling coefficient of 1.6 to ensure that the grouting is dense; specifically, M10 cement mortar is injected into the annular gap between each PHC pipe pile 2 and its pilot hole section, and after curing, the cement mortar layer 4 is formed.

[0033] The topsoil layer 5 is formed by laying 8cm to 12cm of topsoil on the top surface of the boulders platform 1, and the top surface of the topsoil layer and the top surface of each PHC pipe pile are flush with the top surface of the breakwater.

[0034] In this embodiment, based on the 10cm height difference between the top surface of the riprap platform 1 and the breakwater 9, 10cm of topsoil is laid on the top surface of the riprap platform 1 to form a topsoil layer 5; the topsoil layer 5 is manually compacted by a plate tamper to avoid uneven settlement.

[0035] The roadbed layer is formed by multiple roadbed plates 6, which are divided into two groups and laid on the topsoil layer 5 below the designed station positions of the tracks on both sides of the crawler crane 7. The multiple roadbed plates 6 in each group are arranged along the width direction of the track 7b and laid horizontally on the topsoil layer above a group of PHC pipe piles. The multiple rows of PHC pipe piles 2 correspond one-to-one with the multiple roadbed plates 6 and are centrally arranged below the corresponding roadbed plates 6 to ensure that the PHC pipe piles 2 are evenly stressed. The size and number of roadbed plates 6 are adapted to the contact surface size between the track 7b and the ground, so that the plate size formed by laying multiple roadbed plates 6 in each group is larger than the contact area between the track and the ground, and serves as the direct working surface of the crawler crane 7.

[0036] In this embodiment, there are a total of ten roadbed plates 6. Five roadbed plates 6 in each group are arranged in a straight line and laid on the topsoil layer 5 above a group of PHC pipe piles 2 on the same side. The roadbed plates 6 are commercially available roadbed plates with a length × width × thickness of 6.0m × 2.3m × 18cm, so that the track 7b is pressed onto the topsoil layer 5 through the roadbed plates 6. The five roadbed plates 6 correspond one-to-one with the five rows of PHC pipe piles 2 below them, and the center line of each row of PHC pipe piles 2 in the track length direction coincides with the center line of the roadbed plate 6 above it in the track length direction.

[0037] In actual construction, once the wind power construction hoisting platform is completed, the crawler crane 7 enters the site and performs hoisting operations. The crawler crane 7 does not relocate during the entire hoisting process. After the hoisting operation is completed, the hoisting platform does not need to be dismantled and serves as a maintenance platform for the wind turbine's later operation and maintenance. In this embodiment, the construction period for the wind power construction hoisting platform is 4.5 days, which is short.

[0038] Due to the complex geological conditions of the breakwater, after the wind power construction hoisting platform in this embodiment is constructed, a surcharge test is conducted on it to verify the feasibility of the wind power construction hoisting platform construction method of this utility model for strengthening the foundation, and to ensure the reliability of the hoisting platform in subsequent construction operations.

[0039] Given the complex geological conditions of the breakwater, to effectively assess the foundation treatment effect, the surcharge weight is proportional to the maximum weight under lifting conditions, while also considering load partial factors to ensure the reliability of the foundation treatment effect assessment. According to pre-construction calculations, the main loads used on the lifting platform include three parts: an SCC13800 900t crawler crane (total weight 1176.36t), ten roadbed plates (total weight 65t each) arranged below the crawler tracks, and the lifting weight (maximum 183t). The partial factor for the crawler crane's self-weight is 1.5, the partial factor for the lifting weight of 183t is 1.5 x 1.1 (1.1 being the dynamic load factor), and the partial factor for the roadbed plates is 1.2. Therefore, the construction load = 1176.36t × 1.5 + 183t × 1.5 × 1.1 + 65t × 1.2 = 2144.49t. Therefore, based on the analysis above, the foundation bearing capacity requirement of the wind power construction hoisting platform is 1346t, and the load partial factor is 2145t.

[0040] The surcharge test method is as follows: A surcharge platform is set up at the actual station position of the crawler crane 7. The placement of the surcharge blocks should be staggered from the placement gaps of the roadbed plates. Double-beam I-beams are used as distribution beams on the upper part, and the surcharge blocks are evenly distributed on the distribution beams. During the placement of the surcharge blocks, they are arranged in a crisscross pattern and are closely packed to ensure the uniform and continuous transmission of gravity between the upper and lower layers. In this embodiment, a total load of 2145 tons was applied in the surcharge test. At the same time, to ensure surcharge safety, the load on the surcharge blocks was applied in three stages. The first stage reached 65% of the total weight (i.e., 1394 tons), the second stage reached 80% of the total weight (i.e., 1716 tons), and the third stage reached 100% of the total weight (i.e., 2145 tons). Initial values ​​were collected in time before surcharge, and deformation was observed after each loading.

[0041] like Figure 3 As shown, this experiment included 8 vertical displacement observation points, 4 tilt angle observation points, 2 surface settlement observation points, and 1 deep soil horizontal displacement observation point.

[0042] I. Setting up vertical displacement observation points for the loading platform: Set up one settlement observation point at each of the four corners of the roadbed on the north and south sides, for a total of eight points; fix the settlement markers on the roadbed and use an electronic level for observation.

[0043] II. Setting up tilt observation points for the loading platform: A north-south reference beam is erected on the east and west sides of the loading platform. The third point on the reference beam is used as the tilt observation point, and a total of 4 observation points are set up. The tilt is observed using an inclinometer.

[0044] III. Setting up surface settlement observation points: Two surface settlement observation points are set up, one on the north slope shoulder of the breakwater and the other symmetrically arranged on the hoisting platform. The observation method is the same as that for the vertical displacement observation points of the loading platform.

[0045] IV. Setting up deep soil horizontal displacement observation points: Deep horizontal displacement observation points are arranged near the surface settlement observation point (No. 9). Deep horizontal displacement observations are conducted using an inclinometer for data acquisition. At the start of the measurement, the probe is raised from the bottom of the tube to the measurement position, and a reading is taken by a microcomputer every 0.5m of raising. After the reading is completed, the probe is rotated 180 degrees and measured again. The two measurement positions should be consistent, constituting one measurement cycle. Multiple measurement cycles are performed, and the average value is taken.

[0046] Data Acquisition: Initial values ​​are collected before loading. Then, one level of loading is completed daily, with deformation monitoring performed after each loading level. The monitoring frequency is once every 2 hours. If any abnormal phenomena such as an accelerated deformation rate are detected during the monitoring process, loading should be stopped immediately, and the monitoring frequency increased. Loading can resume once the monitoring data stabilizes. After full loading, maintain full load for one day and perform the same monitoring method.

[0047] (I) Results of roadbed settlement test during surcharge period:

[0048] Points ① to ④ are located on the north side of the roadbed box. The maximum cumulative settlement is 47 mm at point ②, the minimum cumulative settlement is 33 mm at point ③, and the average settlement is 38.8 mm. The average settlement rate during the surcharge period is 9.7 mm / d. Points ⑤ to ⑧ are located on the south side of the roadbed box. The maximum cumulative settlement is 36 mm at point ⑤, the minimum cumulative settlement is 23 mm at point ⑧, and the average settlement is 29.8 mm. The average settlement rate during the surcharge period is 7.4 mm / d. A summary of the settlement is shown in Table 1 below.

[0049] Table 1:

[0050]

[0051] In summary, the daily settlement was the largest from the start of the load test until the load reached 65%, with a maximum of 19.4 mm. The daily settlement during the other periods was 3.9 mm to 5.9 mm. The daily settlement at all observation points was less than 50 mm as specified in the control standard.

[0052] (II) Results of uneven settlement test of roadbed subgrade during the surcharge period:

[0053] The results of tilt angle observations and corresponding uneven settlement changes during loading are shown in Table 2 below.

[0054] Table 2:

[0055]

[0056] As can be seen from the test results in Table 2, the uneven settlement between all observation points during the loading period was within the range of 0‰ to 2.8‰, which is less than the 5‰ specified in the control standard.

[0057] (III) Results of surface settlement test during loading period:

[0058] The results of the surface settlement test during the loading period are shown in Table 3 below.

[0059] Table 3:

[0060]

[0061] As can be seen from the test results in Table 3, the foundation settlement behavior during the surcharge process is in line with the general law of soil compression and consolidation, proving that the soil consolidation is stable and no significant uneven settlement or instability has occurred.

[0062] (iv) Results of horizontal displacement tests on deep soil:

[0063] During the loading process, the maximum rate of change of the deep horizontal displacement was 0.76 mm / d (at a depth of 5 m), which is less than the 5 mm / d specified in the control standard; the maximum displacement during the loading process was 1.14 mm (at a depth of 8 m), which is less than the 10 cm specified in the control standard.

[0064] In summary, the wind power construction hoisting platform of this utility model effectively solves the problem of difficult foundation treatment for wind turbine hoisting platforms under breakwater geological conditions. It has significant advantages in terms of construction convenience, safety and reliability, as well as construction period and project cost. It has pioneered the foundation treatment of wind turbine hoisting platforms for riprap breakwaters in China and provides a practical model for the development and construction of breakwater wind power projects nationwide.

Claims

1. A wind power construction hoisting platform suitable for breakwaters, characterized in that, The system includes a boulders platform (1), a PHC pipe pile group, a hillside soil layer (5), and a roadbed plate group. The boulders platform (1) is a boulders layer formed by filling the edge of the breakwater (9) with several boulders. The PHC pipe pile group consists of several PHC pipe piles (2), which are vertically inserted into the boulders layer and the underlying stratum, and are adapted to the maximum load under the hoisting operation conditions. The several PHC pipe piles (2) are divided into two groups and are respectively arranged below the designed station positions of the crawler on both sides of the crawler crane (7). The multiple PHC pipe piles (2) in each group are evenly distributed in multiple rows along the length of the crawler, and the number of PHC pipe piles (2) in each row is at least two. The number of PHC pipe piles (2) in the end rows at both ends is... The quantity is greater than the number of PHC pipe piles (2) located in the middle row; the mountain soil layer (5) is formed by laying mountain soil on the top surface of the boulders platform (1), and the top surface of the mountain soil layer (5) and the top surface of each PHC pipe pile (2) are flush with the top surface of the breakwater (9); the road plate layer is formed by multiple road plate blocks (6), which are divided into two groups to form the direct working surface of the crawler crane (7) on both sides; the multiple road plate blocks (6) of each group are set along the width direction of the crawler and laid horizontally on the mountain soil layer (5) above a group of PHC pipe piles (2), and the multiple rows of PHC pipe piles (2) correspond one-to-one with the multiple road plate blocks (6) and are arranged in the center below the corresponding road plate blocks (6).

2. The wind power construction hoisting platform for breakwaters according to claim 1, characterized in that, The rubble used for filling the rubble platform (1) is made of granite blocks weighing 10 kg / block to 50 kg / block.

3. The wind power construction hoisting platform for breakwaters according to claim 1, characterized in that, PHC pipe piles (2) are inserted into the rock layer and the underlying strata by means of opening a downhole hole in the rock layer.

4. The wind power construction hoisting platform for breakwaters according to claim 3, characterized in that, A cement mortar layer (4) is filled and cured in the annular gap between each PHC pipe pile (2) and the corresponding downhole pilot section.

5. The wind power construction hoisting platform for breakwaters according to claim 1, characterized in that, For each group of multiple PHC pipe piles (2), in the multiple PHC pipe piles (2) located at the end row, the center-to-center distance between the two end PHC pipe piles (2) is greater than the width of the track; in the multiple PHC pipe piles (2) located in the middle row, the center-to-center distance between the two end PHC pipe piles (2) is the same as the width of the track.

6. The wind power construction hoisting platform for breakwaters according to claim 1, characterized in that, PHC pipe pile (2) adopts PHC pipe pile with a closed pile tip (3) at the bottom end.

7. The wind power construction hoisting platform for breakwaters according to claim 1, characterized in that, The height of the soil layer (5) is 8cm~12cm.

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