Steel box formwork for water group pile concrete deck and construction method

Abstract

The present application relates to a kind of steel sleeve box formworks for water group pile concrete deck, including side mould, bottom plate and truss beam three parts, bottom plate is made of middle main rectangular frame and two sides auxiliary rectangular frame and is spliced into "*" type, truss beam is spliced into circle by special-shaped truss beam, side mould is divided into upper and lower side mould, and both are spliced by multiple arc-shaped side moulds.The bottom plate of the steel sleeve box formwork of the present application adopts detachable bottom plate structure, when bottom plate is removed, bottom plate frame height can be lowered using lifting device, leaving construction operation platform, which can save engineering materials, and is also beneficial to the convenience of bottom plate removal operation, and truss beam and side mould are both assembled structure, the overall performance requirement of the steel sleeve box formwork of the present application to lifting equipment is relatively small.

Description

Technical Field

[0001] This invention relates to the field of construction technology for concrete pile caps on water, and in particular to a steel caisson formwork and construction method for concrete pile caps on water. Background Technology

[0002] In the 21st century, more and more countries have begun to vigorously build wind farms, a large part of which are located in the intertidal zone. Intertidal zone construction is one of the important research subjects in offshore wind power project construction, and concrete foundation construction is the key to offshore wind power projects.

[0003] Currently, most concrete foundation piers on water use steel caisson formwork construction technology, which is convenient to install and less affected by weather conditions. Existing steel caisson formwork technologies mostly employ a non-removable base plate and integrated side formwork structure. This type of steel caisson formwork has the following problems: the non-removable base plate cannot be reused, resulting in significant material waste; and the integrated side formwork installation requires high crane lifting capacity, limiting construction options. Summary of the Invention

[0004] This invention provides a steel caisson formwork and construction method for concrete caps of pile groups in water, to solve the problems in the prior art where the bottom plate material of the steel caisson formwork cannot be reused, resulting in serious material waste, and the side formwork installation requires high lifting performance of the crane.

[0005] To achieve the above objectives, the present invention proposes the following technical solution:

[0006] A steel caisson formwork for concrete caps of pile groups in water is cylindrical in shape and includes a base plate, side forms and truss beams. The side forms include an upper side form and a lower side form with the same diameter. The upper side form is formed by splicing arc-shaped upper side forms into a ring, and the lower side form is formed by splicing arc-shaped lower side forms into a ring.

[0007] The base plate is composed of a central main rectangular frame and two auxiliary rectangular frames on both sides, forming an "*" shape;

[0008] The truss beam is formed by splicing together at least two types of irregularly shaped truss beams into a circle.

[0009] Furthermore, the base plate is bolted together from a main rectangular frame and four auxiliary rectangular frames on both sides, and the base plate is provided with a detachable guide rod connecting the main rectangular frame and the auxiliary rectangular frames along the outer side.

[0010] Furthermore, both the upper mold and the lower mold have U-shaped grooves on their upper parts, and the lower mold also has a ring of tapered bolts, with the threaded part of the tapered bolts located inside the lower mold.

[0011] Furthermore, a protective railing is detachably installed on the outer side of the lower mold.

[0012] Furthermore, the steel casing template also includes at least four detachable lifting rods arranged in a ring shape, which can connect the bottom plate and the truss beam vertically.

[0013] A construction method for steel caisson formwork for concrete caps of pile groups on water, the steel caisson formwork includes a base plate, side forms, and truss beams. The side forms include an upper side form and a lower side form with the same diameter. The base plate is formed by assembling a central main rectangular frame and two auxiliary rectangular frames on both sides into a "*" shape. The truss beams are formed by splicing at least two types of irregular truss beams into a circle. The construction method includes a pre-assembly step and a pile-on construction step. The pre-assembly step is carried out on a construction barge or on land. The base plate is assembled using a lifting device, and the lower side forms are assembled along the base plate. Finally, the truss beams are hoisted above the base plate, and the base plate and the truss beams are connected vertically by a hoisting rod.

[0014] The pile construction steps are carried out on the pipe piles. The pre-assembled steel casing template is hoisted onto the pipe piles using a lifting device. The first-stage pile foundation is poured first, then the truss beam and bottom plate are removed, and the upper side formwork is installed for the second-stage pile foundation pouring. After the second-stage pile foundation pouring is completed, the lower side formwork and the upper side formwork are removed.

[0015] Furthermore, before the first-phase foundation is poured, wooden formwork is laid on the base plate to fill the gap between the base plate and the pipe pile.

[0016] Furthermore, both the upper and lower molds are provided with at least four U-shaped slots. Before the first-stage foundation is poured, tie rods are inserted into and connected to the U-shaped slots on the lower mold to tighten it. Before the second-stage foundation is poured, tie rods are inserted into and connected to the U-shaped slots on the upper mold to tighten it.

[0017] Furthermore, during the pouring of the first-phase foundation, U-shaped steel bars are pre-embedded around the perimeter. After the first-phase foundation is completed, the U-shaped steel bars and the base plate are connected using a hand-operated hoist, and then the truss beams are dismantled.

[0018] Furthermore, when the base plate is dismantled, the base plate is lowered using the hand-operated hoist, leaving a manual operating platform between the base plate and the first-phase foundation, and a construction ladder is erected between the first-phase foundation and the main rectangular frame, so that construction workers can repair the base plate of the first-phase foundation.

[0019] The base plate removal step is carried out after the base plate of the first-phase concrete foundation is repaired. Before removal, steel wire ropes are suspended at both ends of the main rectangular frame and the outside of the auxiliary rectangular frame of the base plate, and the steel wire ropes are connected to the U-shaped steel bars of the first-phase concrete foundation. The hand-operated hoist is then removed.

[0020] When the base plate is removed, the construction workers first disconnect the main rectangular frame and the auxiliary rectangular frame on the main rectangular frame. At this time, the auxiliary rectangular frame is in a suspended state. The construction workers can use the lifting device on the first-phase bearing platform to remove the steel wire rope connecting the auxiliary rectangular frame and lift the auxiliary rectangular frame away.

[0021] After the auxiliary rectangular frame is dismantled, construction workers, with the help of a lifting device, remove the steel wire rope connecting the main rectangular frame from the first-phase foundation and lift the main rectangular frame away.

[0022] The beneficial effects of this invention are as follows: The steel caisson formwork base plate of this invention adopts a detachable base plate structure. When the base plate is dismantled, the height of the base plate frame can be lowered using a lifting device to leave a construction work platform, which not only saves engineering materials but also facilitates the base plate dismantling operation. Furthermore, the steel caisson formwork truss beams and side forms of this invention are all assembled structures, and the overall performance requirements of the steel caisson formwork of this invention are relatively low. Attached Figure Description

[0023] Figure 1 This is an elevation view of the steel casing template assembly of the present invention;

[0024] Figure 2 This is an overall hoisting diagram of the steel casing template of the present invention;

[0025] Figure 3 This is an elevation view of the dismantling of the bottom plate of the steel casing template of the present invention;

[0026] Figure 4 This is an elevation view of the installation of the upper side mold of the steel casing template of the present invention;

[0027] Figure 5 This is a schematic diagram of the base plate when the steel casing template of the present invention is erected on the steel pipe pile;

[0028] Figure 6 This is a plan view of the steel casing formwork truss beam of the present invention;

[0029] Figure 7 This is a detailed drawing of a tapered bolt.

[0030] Figure label:

[0031] 1. Steel caisson formwork; 11. Base plate; 111. Main rectangular frame; 112. Auxiliary rectangular frame; 113. Wooden formwork; 121. Lower side formwork; 122. Upper side formwork; 13. Truss beam; 131. Type A truss beam; 132. Type B truss beam; 14. Tie rod; 15. Tapered bolt; 16. Hanger; 17. Guardrail; 18. U-shaped groove; 19. Connecting rod; 2. Steel pipe pile; 3. Crane; 4. Construction barge; 5. Steel platform; 6. Embedded U-shaped steel bars; 7. Hand-operated hoist; 8. Construction ladder; 9. Supporting steel. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be further described clearly and completely below in conjunction with the embodiments of this invention. It should be noted that the described embodiments are merely some embodiments of this invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0033] like Figure 3 and Figure 4 As shown, the steel casing template 1 of the present invention is generally columnar, mainly including a base plate 11, side forms, and truss beams 13. In a specific embodiment of the present invention, as shown... Figure 5 As shown, the base plate 11 is assembled into a "*" shape by a main rectangular frame 111 and four auxiliary rectangular frames; the side molds are divided into upper and lower side molds of the same diameter. The upper side mold is composed of 12 arc-shaped upper templates 122 spliced ​​together, and the lower side mold is composed of 12 arc-shaped lower templates 121 spliced ​​together. Multiple U-shaped slots 18 (at least 4) are provided above both the upper and lower side molds. A guardrail 17 can also be installed along the outer edge of the lower side mold; Figure 6 As shown, truss beam 13 is assembled from two type A truss beams and two type B truss beams.

[0034] The steel casing template 1 of the present invention is mainly divided into a pre-assembly step and a pile construction step during construction.

[0035] like Figure 1As shown, the pre-assembly step is carried out on the construction barge 4 with the help of the crane 3. The crane 3 is mainly used to assemble the bottom plate 11, truss beam 13, and lower side formwork into a whole. During the assembly process, a point is first selected on the deck as the center point of the steel cascade formwork 1 and marked. Then, six steel pipe piles with a diameter of 800mm are used as the steel platform 5. The steel pipe piles are about 2.4m high and the six steel pipe piles are arranged with reference to the plane position of the concrete pile foundation. Then, the supporting steel 9 is welded on the deck of the construction barge 4, and the limiting steel plates are further welded around the supporting steel 9 to limit the main rectangular frame 111 in the bottom plate 11 to avoid collisions that could cause it to shift its position during subsequent hoisting. After hoisting the main rectangular frame 111 to the limiting position, the remaining four auxiliary rectangular frames 112 are hoisted one by one. The auxiliary rectangular frames 112 are connected to the main rectangular frame 111 with bolts. Then, six connecting rods 19 are installed to the outer ends of each rectangular frame and locked to connect the bottom plate 11 into a whole.

[0036] like Figure 6 As shown, during the assembly of truss beam 13, two A-type truss beams 131 and two B-type truss beams 132 are arranged on the base plate 11 according to the design drawings, and finally locked with M30 bolts.

[0037] Furthermore, the assembled truss beam 13 is lifted above the steel platform 5 and its position is adjusted according to the corresponding hanger rod 16 holes on the truss beam 13 and the base plate 11 (in this invention, both the base plate 11 and the truss 13 have pre-reserved holes for installing hanger rods 16). The base plate 11 and the truss 13 are connected by 36 hanger rods arranged in a ring. Four hanger rods 16 can be used for positioning first. After the four positioning hanger rods 16 are connected to the base plate 11 and the truss beam 13, the remaining 32 hanger rods 16 are connected to make the truss beam 13 and the base plate 11 a whole.

[0038] Next, the lower mold is assembled, such as... Figure 1 As shown, 12 lower side formwork pieces 121 are installed one by one onto the base plate 11. The bottom of the lower side formwork pieces 121 is connected to the base plate 11 with M20 bolts. M25 turnbuckles are arranged on the outer edge of the assembled lower side formwork to adjust the diameter of the ring structure so that the finished concrete dimensions of the foundation meet the design requirements.

[0039] Finally, the tie rod 14, made of double-layered 10# channel steel, is passed through the U-shaped groove 18 above the lower mold and locked to prevent the steel casing template 1 from deforming under stress. It should be noted that a ring of tapered bolts 15 is also provided on the lower mold, such as... Figure 7 As shown, the tapered bolt 15 must be installed into the reserved hole of the lower formwork 121 with the bolt facing inward. After the first phase of concrete foundation is poured, the tapered bolt 15 will be embedded in the concrete foundation to provide support for the lower formwork.

[0040] After pre-assembly, the pile construction steps begin, such as... Figure 1As shown, the pre-assembled steel casing template 1 is hoisted simultaneously at four points using crane 3 to a position above the center of the pile position of the steel pipe pile 2 on the foundation slab, so that the steel pipe pile 2 is placed in the gap between the main rectangular frame 111 and the auxiliary rectangular frame 112 on the foundation slab 11. Figure 5 As shown, the top of the steel pipe pile 2 rests on the underside of the truss beam 13, and then the bottom plate 11 is leveled by adjusting the length of the hanger 16.

[0041] Furthermore, such as Figure 5 As shown, the initial pouring of the first-stage concrete foundation is carried out on the base slab 11. After the first-stage concrete foundation meets the design strength requirements, as... Figure 3 As shown, the hanger 16, base plate 11, and truss beam 13 are removed. It should be noted that before the first-phase concrete foundation is poured, if... Figure 5 As shown, wooden formwork 113 is first laid between the main rectangular frame 111 and the auxiliary rectangular frame 112 on the base plate 11 to minimize the gap between the base plate 11 and the steel pipe pile 2. In addition, U-shaped steel bars 6 need to be pre-embedded around the perimeter of the first-phase concrete foundation.

[0042] During the demolition process, the pre-embedded U-shaped steel bars 6 and the base plate 11 are first connected by a hand-operated hoist 7;

[0043] Furthermore, all the lifting rods 16 were removed, and the truss beams 13 were dismantled with the help of the crane 3;

[0044] Furthermore, by using a hand-operated hoist 7, the height of the base plate 11 is lowered to leave space for manual operation. A construction ladder 8 is erected between the lower side formwork and the main rectangular frame 111 of the base plate 11 to facilitate operation. The base plate 11 is used as a platform to remove the wooden formwork 113 and repair the concrete at the bottom of the foundation.

[0045] Furthermore, steel wire ropes are suspended at both ends of the main rectangular frame 111 in the base plate 11 and on the outside of the auxiliary rectangular frame 112 and connected to the U-shaped steel bars 6 of the first-phase concrete foundation, and the hand chain hoist 7 is removed.

[0046] Furthermore, the connecting rod 19 between the base plates was removed;

[0047] Furthermore, loosen the connecting bolts between the base plates 11 one by one, and use a pry bar to detach the auxiliary rectangular frame 112 of the base plate from the support of the main rectangular frame 111 of the base plate. At this time, all auxiliary rectangular frames 112 are suspended by steel wire ropes. With the help of the crane 3, the steel wire ropes connecting the auxiliary rectangular frames 112 can be manually disconnected on the first-stage concrete foundation, and the auxiliary rectangular frames 112 can be removed.

[0048] Finally, with the help of crane 3, the steel wire ropes connecting the two sides of the main rectangular frame 112 were disconnected manually on the first-phase concrete foundation, and the main rectangular frame 112 was dismantled.

[0049] It should be noted that all the dismantled base plates 11 and truss beams 13 were placed on the steel platform 5 to assemble the steel casing formwork 1 for the next working face.

[0050] After the truss beam 13 and the base plate 11 are removed, the 12 upper side templates 122 are installed one by one onto the top of the lower side template 121 with the help of the crane 3, and the corresponding upper side templates 122 and lower side templates 121 are connected with M20 bolts.

[0051] During installation, a hand-operated hoist 7 can be used to connect the U-shaped groove 18 at the top of the upper formwork and the U-shaped reinforcing steel 6 embedded in the first-phase concrete foundation to adjust the verticality of the upper formwork 122. After adjustment, diagonal reinforcing steel bars are used as supports on the inner side of the upper formwork. Finally, as shown in the image... Figure 4 As shown, the tie rod 14, made of double-section 10# channel steel, is inserted into the U-shaped groove 18 above the side mold and locked to prevent the upper edge of the template from deforming under stress.

[0052] Finally, the second-phase concrete foundation is poured. After the second-phase concrete foundation is cured, the upper formwork 122 and the lower formwork 121 are removed, thus completing the turnover of the steel cascade formwork 1.

[0053] As shown in Table 1, this invention has significant advantages compared to other foundation formwork processes.

[0054]

[0055]

[0056] Table 1 Comparison and Analysis of Different Construction Techniques

[0057] Compared with traditional construction techniques such as steel clamp support, precast concrete base plate, and integral steel caisson, the steel caisson formwork of this invention has the advantages of high construction efficiency, fast formwork turnover, low safety risk, high installation accuracy, high overall stability, and low additional consumption.

[0058] The above embodiments are only used to illustrate the technical solutions of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A construction method for a steel caisson formwork for a concrete cap of a group of underwater piles, wherein the steel caisson formwork is cylindrical in shape and includes a base plate, side forms, and truss beams, characterized in that, The side mold includes an upper side mold and a lower side mold of the same diameter. The upper side mold is formed by splicing arc-shaped upper side templates into a ring, and the lower side mold is formed by splicing arc-shaped lower side templates into a ring. The base plate is composed of a central main rectangular frame and two auxiliary rectangular frames on both sides forming an "*" shape, and the lower mold is fixedly connected to the base plate by M20 bolts; The truss beam is formed by splicing together at least two types of irregularly shaped truss beams into a circle; Both the upper mold and the lower mold are provided with at least 4 U-shaped grooves; The base plate is composed of a main rectangular frame and four auxiliary rectangular frames on both sides, which are bolted together. The base plate is also provided with a detachable guide rod that connects the main rectangular frame and the auxiliary rectangular frames along the outer side. The steel casing formwork also includes at least four detachable lifting rods, which are arranged in a ring and connect the bottom plate and the truss beam at the top and bottom. The construction method for the steel caisson formwork for concrete caps of pile groups on water includes a pre-assembly step and a pile construction step. The pre-assembly step is carried out on a construction barge or on land. The bottom plate is assembled using a lifting device, and the lower side formwork is assembled along the bottom plate. Finally, the truss beam is hoisted above the bottom plate, and the bottom plate and the truss beam are connected vertically by a lifting rod. The pile construction steps are carried out on the pipe piles. The pre-assembled steel casing template is hoisted onto the pipe piles using a lifting device. The first-stage pile cap is poured first, then the truss beam and bottom plate are removed, and the upper side formwork is installed for the second-stage pile cap pouring. After the second-stage pile cap pouring is completed, the lower side formwork and the upper side formwork are removed. Before the first-stage foundation is poured, tie rods are inserted into and connected to the U-shaped grooves on the lower side mold to tighten the lower side mold; before the second-stage foundation is poured, tie rods are inserted into and connected to the U-shaped grooves on the upper side mold to tighten the upper side mold. During the pouring of the first-phase foundation, U-shaped steel bars were pre-embedded around the perimeter. After the first-phase foundation was poured, the U-shaped steel bars and the base plate were connected by a hand-operated hoist, and then the truss beams were dismantled. When the base plate is removed, the hand-operated hoist is used to lower the base plate, leaving a manual operation platform between the base plate and the first-phase foundation, and a construction ladder is erected between the first-phase foundation and the main rectangular frame, so that construction workers can repair the base plate of the first-phase foundation. The base plate removal step is carried out after the base plate of the first-phase concrete foundation is repaired. Before removal, steel wire ropes are suspended at both ends of the main rectangular frame and the outside of the auxiliary rectangular frame of the base plate, and the steel wire ropes are connected to the U-shaped steel bars of the first-phase concrete foundation. The hand-operated hoist is then removed. When the base plate is removed, the construction workers first disconnect the main rectangular frame and the auxiliary rectangular frame on the main rectangular frame. At this time, the auxiliary rectangular frame is in a suspended state. The construction workers, with the help of the lifting device, remove the steel wire rope connecting the auxiliary rectangular frame on the first-phase bearing platform and lift the auxiliary rectangular frame away. After the auxiliary rectangular frame is dismantled, construction workers, with the help of a lifting device, remove the steel wire rope connecting the main rectangular frame from the first-phase foundation and lift the main rectangular frame away.

2. The construction method for steel caisson formwork for concrete caps of underwater pile groups according to claim 1, characterized in that, The U-shaped groove is provided on the upper part of the upper mold and the lower mold, and a ring of tapered bolts is also provided on the lower mold, with the threaded part of the tapered bolts located inside the lower mold.

3. The construction method for steel caisson formwork for concrete caps of underwater pile groups according to claim 1, characterized in that, The lower side mold has a detachable guardrail installed on its outer side.

4. The construction method for steel caisson formwork for concrete caps of underwater pile groups according to claim 1, characterized in that, Before the first phase of the foundation pier is poured, wooden formwork is laid on the base slab to fill the gap between the base slab and the pipe pile.

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