Integral dismantling method for hanging basket formwork of rigid frame bridge

Abstract

The invention discloses an integral dismantling method for a rigid frame bridge hanging basket formwork, and relates to the technical field of bridge engineering construction. The problems that in the prior art, the rigid frame bridge hanging basket formwork dismantling efficiency is low, potential safety hazards are high, and cost is high are solved. The dismantling method comprises the following steps of: pre-burying a winch anchor bolt to anchor a winch; loosening a hanging basket anchor system to separate a hanging basket bottom die from a concrete box girder; arranging four winches to be matched with fixed pulleys; synchronously lifting the hanging basket bottom die for static load test, then synchronously lowering the hanging basket bottom die to the ground, and decomposing and dismantling the hanging basket bottom die on the ground. And the hanging basket truss is disassembled on the bridge floor. The integral dismantling method for the hanging basket formwork of the rigid frame bridge is used for dismantling the hanging basket bottom formwork of the rigid frame bridge, an integral dismantling mode is adopted, high-altitude split operation of the hanging basket bottom formwork is converted into integral ground dismantling, the operation time is shortened, and the dismantling efficiency is improved; the template loss is reduced, and the cost is reduced; aloft work is reduced, and potential safety hazards are reduced. The method is particularly suitable for large-span bridge engineering crossing rivers and seas or expressways.

Description

Technical Field

[0001] The invention belongs to the technical field of bridge engineering construction, and in particular relates to a method for integrally dismantling a hanging basket formwork of a rigid frame bridge. Background Art

[0002] As the core temporary support system for cantilever casting of long-span bridges, the hanging basket's high structural complexity (including modules such as the main truss, bottom formwork platform, and suspension system) directly impacts construction efficiency and safety. In traditional segmented construction, the hanging basket requires repeated disassembly and assembly, and the disassembly process involves working at height, near water, and along nearby edges, posing a significant risk of accidents. This is especially true when constructing over water or above major traffic arteries, where both structural safety and environmental protection must be considered.

[0003] Traditional demolition methods have the following limitations: the efficiency of block dismantling is low: traditional manual block demolition relies on hand winches or tower cranes, which have the risk of uneven force on the lifting points and the risk of formwork overturning, and is time-consuming (5-7 days for a single demolition). Safety control is difficult: high-altitude workers need to frequently enter the bottom formwork platform for operation, and falling object accidents are prone to occur when the protective scaffolding is dismantled, posing a major safety hazard, especially when crossing waterways or highways, traffic must be interrupted; high-altitude operations need to be broken down into small express items, the formwork is more damaged, and the recycling and reuse rate is low, which increases costs; equipment coordination requirements are high: split lifting relies on the cooperation of tower cranes and lifting machinery, and has strict requirements on anchoring accuracy and synchronous lowering control, and the main truss is prone to instability due to track deviation. Summary of the Invention

[0004] The present invention provides a method for overall dismantling of a rigid frame bridge hanging basket formwork, wherein the hanging basket bottom formwork is overall dismantled, thereby shortening operation time and improving dismantling efficiency; the recovery rate is high, template loss is reduced, and costs are lowered; high-altitude operations are reduced, safety hazards are reduced, and worker safety is ensured.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] The present invention discloses a method for integrally dismantling a rigid frame bridge hanging basket formwork, comprising the following steps:

[0007] S1. Pre-embed the anchor bolts of four winches at the closure section of the rigid frame bridge;

[0008] S2. After the closure section of the rigid frame bridge is cast and the prestressed anchors are sealed, the hanging basket anchor system between the hanging basket bottom formwork and the concrete box girder is loosened to separate the hanging basket bottom formwork from the concrete box girder;

[0009] S3. Select a winch and a steel wire rope according to the weight of the hanging basket bottom formwork, wind one end of the steel wire rope around the drum of the winch, and fix the winch to the rigid frame bridge through the pre-buried anchor bolts of the winch;

[0010] S4. Setting hanging points at the left and right ends of the front crossbeam and the left and right ends of the rear crossbeam of the hanging basket bottom formwork, and installing fixed pulleys at the left and right ends of the upper crossbeam and the left and right ends of the lower crossbeam of the hanging basket truss. The fixed pulleys of the upper crossbeam of the hanging basket truss correspond one-to-one with the hanging points of the front crossbeam of the hanging basket bottom formwork, and the fixed pulleys of the lower crossbeam of the hanging basket truss correspond one-to-one with the hanging points of the rear crossbeam of the hanging basket bottom formwork. The other end of the steel wire rope passes over the corresponding fixed pulley and is connected to the hanging point.

[0011] S5. Synchronously start the winch to retract the rope, tighten the wire rope of the winch, stop the winch after tightening the wire rope, and then statically load the basket. Loosen the basket anchoring system between the basket truss and the basket bottom formwork, so that the basket truss is separated from the basket bottom formwork. The basket truss is disassembled and removed on the bridge deck of the rigid frame bridge by workers using a crane.

[0012] S6. Synchronously start the winch to release the rope, and the hanging basket bottom formwork is lowered along with the wire rope. After the hanging basket bottom formwork is lowered to the ground under the bridge, workers cooperate with the crane to disassemble and remove the hanging basket bottom formwork.

[0013] Furthermore, in step S2, a hand winch is used to gradually release the load to separate the hanging basket bottom formwork from the concrete box beam, and the distance between the hanging basket bottom formwork and the concrete box beam is not less than 10 cm.

[0014] Furthermore, the distance between the hanging basket bottom formwork and the concrete box beam is 10cm-50cm.

[0015] Furthermore, in step S5, the four winches are started to synchronously lift the bottom formwork of the hanging basket by 10 cm-30 cm, and after static loading for 30 minutes, the uniformity and stability of the force applied to each of the hanging points are checked.

[0016] Furthermore, in step S6, the rope-releasing speed v of the winch is ≤ 10 cm / min.

[0017] Furthermore, in step S1, four winch anchor bolts 10 are reserved for each winch.

[0018] Furthermore, in step S4, a hook is installed at the other end of the wire rope, and wire rope loops are installed at the corresponding hanging points at the left and right ends of the front beam and the left and right ends of the rear beam of the hanging basket bottom mold. When the corresponding wire rope is connected to the hanging point, the hook is hung on the wire rope loop.

[0019] Furthermore, D32 finish-rolled threaded steel bars are inserted into the left and right ends of the front crossbeam and the left and right ends of the rear crossbeam of the hanging basket bottom mold, and the D32 finish-rolled threaded steel bars are located on the outside of the corresponding hanging points.

[0020] The beneficial effects of the present invention are:

[0021] The present application discloses a method for overall dismantling of a basket formwork for a rigid frame bridge, which comprises: pre-embedding and anchoring the winch anchor bolts of four winches; loosening the basket anchor system between the basket bottom formwork and the concrete box beam to separate the basket bottom formwork from the concrete box beam; installing four winches on the rigid frame bridge, and winding one end of the wire rope around the drum of the corresponding winch; hoisting fixed pulleys at the left and right ends of the upper beam of the basket truss and the left and right ends of the lower beam, and the other end of the wire rope passes around the corresponding fixed pulleys and is connected to the corresponding lifting points of the front beam and the rear beam of the basket bottom formwork; synchronously starting the winch to retract the rope, stopping the winch after the wire rope is tightened, and then statically loading, loosening the basket anchor system between the basket truss and the basket bottom formwork; synchronously starting the winch to release the rope, and lowering the basket bottom formwork to the ground under the bridge; the basket bottom formwork as a whole is modularly disassembled and dismantled on the ground by workers in cooperation with a crane; and the basket truss is disassembled and dismantled on the bridge deck. The overall dismantling method of the hanging basket formwork of the rigid frame bridge of the present application is used to dismantle the bottom formwork of the hanging basket of the rigid frame bridge. The overall dismantling method is adopted to convert the high-altitude split operation of the hanging basket bottom formwork into an overall lowering to the ground for dismantling and dismantling, thereby reducing high-altitude operations, reducing safety hazards, and ensuring the safety of workers. Compared with the traditional dismantling method which takes 5-7 days for a single dismantling, the overall dismantling time of the hanging basket formwork of the present application can be shortened to 8-12 hours, which is 80% more efficient than the traditional method, greatly shortening the operation time and improving the dismantling efficiency. The bottom formwork of the hanging basket is modularly dismantled and dismantled on the ground as a whole, without the need to be decomposed into small pieces, reducing the loss of the formwork, and the complete recovery rate of the modular components exceeds 95%, with a high reuse rate and reduced costs. The overall dismantling method of the hanging basket formwork of the present application is particularly suitable for large-span bridge projects across rivers, seas or highways. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 This is a flow chart of a method for integrally dismantling a rigid frame bridge hanging basket formwork provided by an embodiment of the present invention;

[0024] Figure 2 This is a front view of an integral dismantling device for a rigid frame bridge hanging basket formwork provided by an embodiment of the present invention;

[0025] Figure 3 It is a side view of an overall dismantling device for a rigid frame bridge hanging basket formwork provided by an embodiment of the present invention.

[0026] Reference numerals:

[0027] Rigid frame bridge 1, upper crossbeam 2, lower crossbeam 3, winch 4, fixed pulley 5, wire rope 6, wire rope loop 7, front crossbeam 8, rear crossbeam 9, winch anchor bolt 10. DETAILED DESCRIPTION

[0028] To make the objectives, technical solutions, and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other implementations obtained by those of ordinary skill in the art without inventive effort are within the scope of protection of the present invention.

[0029] The present invention will be further described below with reference to the accompanying drawings and examples.

[0030] like Figure 1 、 Figure 2 、 Figure 3 As shown, a method for dismantling a rigid frame bridge hanging basket formwork as a whole according to the present invention comprises a hanging basket formwork comprising a hanging basket truss and a hanging basket bottom formwork suspended below the hanging basket truss, wherein the hanging basket truss is located above the rigid frame bridge deck, and the hanging basket bottom formwork is located below the rigid frame bridge deck, comprising the following steps:

[0031] S1, pre-embed the hoist anchor bolts 10 of four hoists 4 at the closure section of the rigid frame bridge 1;

[0032] S2. After the closure section of the rigid frame bridge 1 is cast and the prestressed anchors are sealed, the hanging basket anchoring system between the hanging basket bottom formwork and the concrete box girder is loosened to separate the hanging basket bottom formwork from the concrete box girder;

[0033] S3. Select a winch 4 and a steel wire rope 6 according to the weight of the basket bottom formwork, wind one end of the steel wire rope 6 around the drum of the winch 4, and fix the winch 4 to the rigid frame bridge 1 through the pre-buried winch anchor bolts 10;

[0034] S4. Hanging points are set at the left and right ends of the front crossbeam 8 and the left and right ends of the rear crossbeam 9 of the hanging basket bottom formwork, and fixed pulleys 5 are hoisted at the left and right ends of the upper crossbeam 2 and the left and right ends of the lower crossbeam 3 of the hanging basket truss. The fixed pulleys 5 of the upper crossbeam 2 of the hanging basket truss correspond to the hanging points of the front crossbeam 8 of the hanging basket bottom formwork one by one, and the fixed pulleys 5 of the lower crossbeam 3 of the hanging basket truss correspond to the hanging points of the rear crossbeam 9 of the hanging basket bottom formwork one by one. The other ends of the steel wire ropes 6 pass over the corresponding fixed pulleys 5 and are connected to the corresponding hanging points;

[0035] S5. Synchronously start the hoist 4 to retract the rope, tighten the wire rope 6 of the hoist 4, stop the hoist 4 after tightening the wire rope 6, and release the hanging basket anchoring system (such as slings and finished rolled threaded steel bars) between the hanging basket truss and the hanging basket bottom formwork, so that the hanging basket truss is separated from the hanging basket bottom formwork. The hanging basket truss is disassembled and removed on the bridge deck of the rigid frame bridge by workers using a crane.

[0036] S6. Synchronously start the hoist 4 to release the rope, and the hanging basket bottom formwork is lowered along with the wire rope 6. After the hanging basket bottom formwork is lowered to the ground under the bridge, workers cooperate with the crane to disassemble and remove the hanging basket bottom formwork.

[0037] The winch 4 is an 18.5kW winch with a maximum load capacity of 10t. The wire rope 6 is a 6×7-FC φ24 steel rope with a minimum breaking force of 30t, ensuring both traction and safety redundancy. The winch 4 can be powered by an external power supply. The fixed pulleys 5 are mounted via lifting lugs on the left and right ends of the upper crossbeam 2 and the left and right ends of the lower crossbeam 3 of the gantry truss.

[0038] Based on the above-mentioned method for dismantling the entire basket formwork of a rigid frame bridge, the dismantling method includes: pre-embedding the anchor bolts 10 of the four winches 4; loosening the basket anchor system between the basket bottom formwork and the concrete box beam to separate the basket bottom formwork from the concrete box beam; installing the four winches 4 on the rigid frame bridge 1, and winding one end of the wire rope 6 on the drum of the corresponding winch 4; hoisting the left and right ends of the upper beam 2 and the left and right ends of the lower beam 3 of the basket truss to fix The pulley 5 and the other end of the wire rope 6 pass around the corresponding fixed pulley 5 and are connected to the corresponding lifting points of the front crossbeam 8 and the rear crossbeam 9 of the hanging basket bottom formwork; the winch 4 is started synchronously to retract the rope, and after the wire rope 6 is tightened, the winch is stopped and then statically loaded, and the hanging basket anchoring system between the hanging basket truss and the hanging basket bottom formwork is loosened; the winch 4 is started synchronously to release the rope, and the hanging basket bottom formwork is lowered to the ground under the bridge; the hanging basket bottom formwork is modularly disassembled and dismantled on the ground by workers in cooperation with the crane; the hanging basket truss is disassembled and dismantled on the bridge deck. The overall dismantling method of the hanging basket formwork of the rigid frame bridge of the present application is used to dismantle the bottom formwork of the hanging basket of the rigid frame bridge. The overall dismantling method is adopted to convert the high-altitude split operation of the hanging basket bottom formwork into an overall lowering to the ground for dismantling and dismantling, thereby reducing high-altitude operations, reducing safety hazards, and ensuring the safety of workers. Compared with the traditional dismantling method which takes 5-7 days for a single dismantling, the overall dismantling time of the hanging basket formwork of the present application can be shortened to 8-12 hours, which is 80% more efficient than the traditional method, greatly shortening the operation time and improving the dismantling efficiency. The bottom formwork of the hanging basket is modularly dismantled and dismantled on the ground as a whole, without the need to be decomposed into small pieces, reducing the loss of the formwork, and the complete recovery rate of the modular components exceeds 95%, with a high reuse rate and reduced costs. The overall dismantling method of the hanging basket formwork of the present application is particularly suitable for large-span bridge projects across rivers, seas or highways.

[0039] As an implementable method, Figure 1 、 Figure 2 、 Figure 3 As shown, in step S2, the hanging basket bottom formwork is separated from the concrete box beam by gradually releasing the load using a hand winch, and the distance between the hanging basket bottom formwork and the concrete box beam is not less than 10 cm.

[0040] The initial separation distance between the hanging basket bottom form and the concrete box beam is not less than 10 cm, which is convenient for the subsequent hoisting of the wire rope 6 of the winch 4.

[0041] As an implementable method, Figure 1 、 Figure 2 、 Figure 3 As shown, the distance between the hanging basket bottom formwork and the concrete box beam is 10cm-50cm.

[0042] The spacing between the bottom formwork of the hanging basket and the concrete box beam is initially 10cm-50cm, such as 10cm, 20cm, 30cm, 40cm, or 50cm, which is selected based on the convenience of subsequent hoisting of the wire rope 6 of the winch 4. In order to facilitate the separation of the bottom formwork of the hanging basket from the concrete box beam, the hanging basket anchoring system between the hanging basket truss and the concrete box beam is loosened.

[0043] As an implementable method, Figure 1 、 Figure 2 、 Figure 3 As shown, in step S5, the four winches 4 are started to synchronously lift the bottom formwork of the hanging basket by 10 cm-30 cm, and after static loading for 30 minutes, the uniformity and stability of the force applied to each hanging point are checked.

[0044] Lift the bottom formwork of the hanging basket by 10cm-30cm. For example, if the bottom formwork of the hanging basket is lifted by 10cm, 20cm, or 30cm, hold it statically for 30 minutes, check that the force on each lifting point is uniform and stable, check that there is no deformation or detachment at the connection between the wire rope 6 and the lifting point, check that the bottom formwork of the hanging basket is not tilted, and ensure that the bottom formwork of the hanging basket can be safely lowered to the ground under the bridge later.

[0045] As an implementable method, Figure 1 、 Figure 2 、 Figure 3 As shown, in step S5, a synchronous controller can be used to control the synchronous release of the four winches 4. A displacement sensor (such as a rotary encoder or a distance measuring code disk) can be installed in the motor reducer of each winch 4. The synchronous controller is electrically connected to the displacement sensor and the winch motor via wires. The synchronous controller receives real-time data from the displacement sensor and calculates the displacement deviation between the winches. The synchronous controller adjusts the motor speed of each winch based on the displacement deviation to ensure synchronous release of the winches 4. The synchronous controller can be powered by an external power supply.

[0046] As an implementable method, Figure 1 、 Figure 2 、 Figure 3 As shown, in step S6, the rope-releasing speed v of the hoist 4 is ≤ 10 cm / min.

[0047] The rope-releasing speed v of the winch 4 is ≤ 10 cm / min, so that the lowering speed of the hanging basket bottom formwork is less than or equal to 10 cm / min, and the hanging basket bottom formwork is lowered slowly to ensure safety.

[0048] As an implementable method, Figure 1 、 Figure 2 、 Figure 3 As shown, in step S1 , four hoist anchor bolts 10 are reserved for each hoist 4 .

[0049] Each winch 4 is stably fixed on the rigid frame bridge 1 via four reserved winch anchor bolts 10 .

[0050] As an implementable method, Figure 1 、 Figure 2 、 Figure 3 As shown, in step S4, a hook is installed at the other end of the wire rope 6, and a wire rope loop 7 is installed at the corresponding hanging points at the left and right ends of the front crossbeam 8 and the left and right ends of the rear crossbeam 9 of the hanging basket bottom mold. When the corresponding wire rope 6 is connected to the hanging point, the hook is hung on the wire rope loop 7.

[0051] Wire rope loops 7 are installed at the left and right hanging points of the front crossbeam 8 and the rear crossbeam 9 of the basket base form. The end of the wire rope 6, opposite the end of the hoist 4, passes through the holes in the hooks and is secured to the hooks using wire rope clamps. The hooks are suspended from the corresponding wire rope loops 7 to ensure a secure connection. The wire rope loops 7 are made of φ24 steel wire rope with a minimum breaking force of 30 tons.

[0052] As an implementable method, Figure 1 、 Figure 2 、 Figure 3 As shown, D32 finished rolled threaded steel bars are inserted into the left and right ends of the front crossbeam 8 and the left and right ends of the rear crossbeam 9 of the hanging basket bottom mold, and the D32 finished rolled threaded steel bars are located on the outside of the corresponding hanging points.

[0053] The D32 high-quality rolled rebar is located outside the corresponding lifting point, and the distance between the D32 high-quality rolled rebar and the left and right ends of the front crossbeam 8 and rear crossbeam 9 is less than the distance between the lifting point and the left and right ends of the front crossbeam 8 and rear crossbeam 9. The D32 high-quality rolled rebar is penetrated and welded to the left and right ends of the front crossbeam 8 and rear crossbeam 9 of the hanging basket bottom formwork. The D32 high-quality rolled rebar blocks the wire rope loop 7, preventing it from slipping off the left and right ends of the front crossbeam 8 and rear crossbeam 9 of the hanging basket bottom formwork, ensuring that the hanging basket bottom formwork is securely lowered.

[0054] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be covered by the scope of protection of the present invention.

Claims

1. The overall dismantling method of the rigid frame bridge hanging basket formwork is characterized by: The following steps are involved: S1, pre-embedding the winch anchor bolts (10) of four winches (4) in the closure section of the rigid frame bridge (1); S2. After the closure section of the rigid frame bridge (1) is cast and the prestressed anchors are sealed, the hanging basket anchoring system between the hanging basket bottom formwork and the concrete box beam is loosened to separate the hanging basket bottom formwork from the concrete box beam; S3, selecting a winch (4) and a steel wire rope (6) according to the weight of the hanging basket bottom formwork, winding one end of the steel wire rope (6) on the drum of the winch (4), and fixing the winch (4) on the rigid frame bridge (1) through the pre-buried winch anchor bolts (10); S4, setting hanging points at the left and right ends of the front crossbeam (8) and the left and right ends of the rear crossbeam (9) of the hanging basket bottom formwork, hanging fixed pulleys (5) at the left and right ends of the upper crossbeam (2) and the left and right ends of the lower crossbeam (3) of the hanging basket truss, the fixed pulleys (5) of the upper crossbeam (2) of the hanging basket truss corresponding to the hanging points of the front crossbeam (8) of the hanging basket bottom formwork, the fixed pulleys (5) of the lower crossbeam (3) of the hanging basket truss corresponding to the hanging points of the rear crossbeam (9) of the hanging basket bottom formwork, the other end of the steel wire rope (6) passes around the corresponding fixed pulley (5) and is connected to the hanging point; S5, synchronously starting the hoist (4) to reel in the rope, tightening the steel wire rope (6) of the hoist (4), stopping the hoist (4) after tightening the steel wire rope (6), and then statically loading, loosening the hanging basket anchoring system between the hanging basket truss and the hanging basket bottom formwork, separating the hanging basket truss from the hanging basket bottom formwork, and dismantling the hanging basket truss on the rigid frame bridge deck by workers in conjunction with a crane; S6. Synchronously start the hoist (4) to release the rope, and the hanging basket bottom formwork is lowered along with the steel wire rope (6). After the hanging basket bottom formwork is lowered to the ground under the bridge, workers cooperate with the crane to disassemble and remove the hanging basket bottom formwork.

2. The method for dismantling the rigid frame bridge hanging basket formwork as claimed in claim 1 is characterized in that: In step S2, the hanging basket bottom formwork is separated from the concrete box beam by gradually releasing the load using a hand winch, and the distance between the hanging basket bottom formwork and the concrete box beam is not less than 10 cm.

3. The method for dismantling the rigid frame bridge hanging basket formwork as claimed in claim 2 is characterized in that: The distance between the hanging basket bottom formwork and the concrete box beam is 10cm-50cm.

4. The method for dismantling the entire rigid frame bridge hanging basket formwork according to claim 1 is characterized in that: In step S5, the four hoists (4) are started to synchronously lift the bottom formwork of the hanging basket by 10 cm to 30 cm, and after 30 minutes of static loading, the uniformity and stability of the force applied to each of the hanging points are checked.

5. The method for dismantling the entire rigid frame bridge hanging basket formwork according to claim 1 is characterized in that: In step S6, the rope-releasing speed v of the hoist (4) is ≤ 10 cm / min.

6. The method for dismantling the entire rigid frame bridge hanging basket formwork according to claim 1 is characterized in that: In step S1, four winch anchor bolts 10 are reserved for each winch (4).

7. The method for dismantling the entire rigid frame bridge hanging basket formwork according to claim 1 is characterized in that: In step S4, a hook is installed at the other end of the steel wire rope (6), and a steel wire rope loop (7) is set at the corresponding hanging points at the left and right ends of the front cross beam (8) and the left and right ends of the rear cross beam (9) of the hanging basket bottom mold. When the corresponding steel wire rope (6) is connected to the hanging point, the hook is hung on the steel wire rope loop (7).

8. The method for dismantling the entire rigid frame bridge hanging basket formwork according to claim 7 is characterized in that: D32 finished rolled threaded steel bars are inserted into the left and right ends of the front crossbeam (8) and the left and right ends of the rear crossbeam (9) of the hanging basket bottom mold, and the D32 finished rolled threaded steel bars are located outside the corresponding hanging points.

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