A dismantling method suitable for continuous multi-span arch bridge structure

Abstract

The present invention provides a dismantling method suitable for a continuous multi-span arch bridge structure, by first dismantling the first main bridge deck and the second main bridge deck of the arch bridge structure, and then dismantling the first main bridge longitudinal and transverse beams, the first hanger assembly and the second main bridge longitudinal and transverse beams and the second hanger assembly, and then dismantling the first approach bridge deck and the second approach bridge deck, the first arch upper column assembly and the second arch upper column assembly, and finally dismantling the first main arch ring, the second main arch ring and the first side arch ring and the second side arch ring. In an embodiment of the present application, lighter structures such as the first main bridge deck are removed first, and then heavier components such as the first main arch ring are gradually removed, which helps to maintain the stability of the arch bridge structure until the bridge dismantling is completed, and enables the dismantling work to be carried out safely and efficiently.

Description

Technical Field

[0001] The invention relates to the technical field of bridge engineering, and in particular to a dismantling method suitable for a continuous multi-span arch bridge structure. Background Art

[0002] In common use technology, bridges are usually equipped with one-way thrust piers, which can provide horizontal force to the remaining structure during the bridge demolition process. For the demolition of multi-arch bridges, the reverse method is often used, that is, the bridges are demolished in sequence according to the steps opposite to the original bridge construction.

[0003] However, in actual projects, there are still some bridges that are not equipped with unidirectional thrust piers. The main bridge and approach bridge of such bridges are an organic whole. When one span of such bridge is demolished, the unbalanced force will be transmitted in the entire structure, affecting the stress of the entire bridge and posing a risk of continuous collapse. In this case, it is necessary to consider the stress conditions of the entire bridge in order to design the corresponding construction steps. Only the reverse method cannot be used for safe demolition.

[0004] At the same time, there are some very old bridges. Due to incomplete data preservation and lack of clear description of the bridge construction process, the construction process of the bridge is unclear. It is even more impractical to use conventional reverse methods to demolish such bridges.

[0005] Based on this, it is necessary to provide a dismantling method suitable for continuous multi-span arch bridge structures to alleviate or solve the above problems. Summary of the invention

[0006] In order to solve the technical problems in the above-mentioned conventional technologies, the present invention provides a method for dismantling a continuous multi-span arch bridge structure, comprising the following steps:

[0007] S1, dismantle the first main bridge deck located at the first main arch section and the second main bridge deck located at the second main arch section; wherein the arch bridge structure comprises the first main arch section and the second main arch section connected along the longitudinal direction of the bridge, a plurality of first side arch sections located at the sides of the first main arch section, and a plurality of second side arch sections located at the sides of the second main arch section; wherein the first main arch section comprises the first main arch ring, the first main bridge deck, the first main bridge longitudinal and transverse beams, and the first suspender assembly for connecting the first main bridge longitudinal and transverse beams and the first main arch ring, and the second main arch section comprises the second main arch ring, the second main bridge deck, the second main bridge longitudinal and transverse beams, and the second suspender assembly for connecting the second main bridge longitudinal and transverse beams and the second main arch ring;

[0008] S2, dismantling the first main bridge longitudinal and transverse beams, the first hanger assembly, the second main bridge longitudinal and transverse beams, and the second hanger assembly, and retaining the first main arch ring and the second main arch ring;

[0009] S3, dismantling all first approach bridge panels located at the first side arch section and all second approach bridge panels located at the second side arch section; wherein each of the first side arch sections comprises a first side arch ring, a first arch column assembly, and a first approach bridge panel laid on top of the first arch column assembly, and each of the second side arch sections comprises a second side arch ring, a second arch column assembly, and a second approach bridge panel laid on top of the second arch column assembly;

[0010] S4, removing all first arch upper column assemblies and second arch upper column assemblies, and retaining all first side arch rings and second side arch rings;

[0011] S5, removing the first main arch ring, the second main arch ring, the first side arch ring, and the second side arch ring;

[0012] S6, dismantling all bridge piers to complete the dismantling of the arch bridge structure.

[0013] In one embodiment, the step S5 specifically includes the steps of:

[0014] S51, determining the maximum value of the unbalanced horizontal force of each pier of the arch bridge structure before demolition, and using the maximum value of the unbalanced horizontal force of each pier as the bridge demolition horizontal force limit value of the corresponding pier;

[0015] S52, calculating the unbalanced horizontal force for each bridge pier after step S4, obtaining a first unbalanced horizontal force calculation value for each bridge pier, and determining whether the first unbalanced horizontal force calculation value for each bridge pier is lower than a corresponding bridge demolition horizontal force limit value;

[0016] S53, when the calculated values ​​of the first unbalanced horizontal forces of all bridge piers are lower than the corresponding bridge demolition horizontal force limit values, it is determined that the demolition working condition of the arch bridge structure is safe, and then the first main arch ring and the second main arch ring are synchronously demolished;

[0017] S54, performing unbalanced horizontal force calculation again on each bridge pier after step S53, obtaining a second unbalanced horizontal force calculation value of each bridge pier, and determining whether the second unbalanced horizontal force calculation value of each bridge pier is lower than the corresponding bridge demolition horizontal force limit value;

[0018] S55, when the calculated values ​​of the second unbalanced horizontal force on all bridge piers are lower than the corresponding bridge demolition horizontal force limit values, it is determined that the demolition working condition of the arch bridge structure is safe, and then the first side arch ring and the second side arch ring are demolished.

[0019] In one embodiment, the step S51 specifically includes the following steps:

[0020] S511, calculating the horizontal force F1 borne by each of the bridge piers under the action of its own weight when the arch bridge structure is in a completed state;

[0021] S512, calculating the maximum value F2 of the horizontal force borne by each of the bridge piers when the arch bridge structure is in operation;

[0022] S513, multiplying the horizontal force F1 and the maximum horizontal force F2 by their respective partial coefficients, combining and adding them, to obtain the horizontal force F3 borne by each pier, and using the horizontal force F3 corresponding to each pier as the bridge demolition horizontal force limit corresponding to each pier.

[0023] In one embodiment, the first side arch ring includes four first arch ribs arranged along the transverse bridge direction, and the second side arch ring includes four second arch ribs arranged along the transverse bridge direction, wherein:

[0024] Before the synchronous removal of the first main arch ring and the second main arch ring in step S53, the following steps are included:

[0025] First, remove the two first arch ribs located in the middle of the bridge in all the first side arch rings and the two second arch ribs located in the middle of the bridge in all the second side arch rings, and then simultaneously remove the first main arch ring and the second main arch ring.

[0026] In one embodiment, removing the first arch rib and the second arch rib specifically comprises the steps of:

[0027] Cutting longitudinally the two first arch ribs located in the middle of the bridge in the first side arch ring and the two second arch ribs located in the middle of the bridge in the second side arch ring, decomposing the two first arch ribs located in the middle of the bridge in the first side arch ring and the two second arch ribs located in the middle of the bridge in the second side arch ring;

[0028] The two first arch ribs in the first side arch ring located in the middle of the bridge and the two second arch ribs in the second side arch ring located in the middle of the bridge are removed by transverse segment cutting, and the first arch rib and the second arch rib located on the outside of the bridge in the first side arch ring and the second side arch ring are retained.

[0029] In one embodiment, the step S53 specifically includes the steps of:

[0030] S531, using a floating support platform device to dismantle the first main arch ring and the second main arch ring; wherein the floating support platform device comprises a floating vessel and a support working platform disposed on the floating vessel, and before dismantling the first main arch ring and the second main arch ring, firstly fasten the support working platform and the first main arch ring and the second main arch ring, and then use the support working platform to lift the first main arch ring and the second main arch ring;

[0031] S532, cutting the first main arch ring and the second main arch ring from the arch foot position, and then cutting the first main arch ring and the second main arch ring in sections, and using the support working platform to carry the cut first main arch ring and the second main arch ring;

[0032] S533: Use the floating vessel to transport the first main arch ring and the second main arch ring.

[0033] In one embodiment, the step S54 specifically includes the following steps:

[0034] S541, simulating the bridge dismantling construction process, calculating the second unbalanced horizontal force F4 borne by each bridge pier after step S53;

[0035] S542, determining whether the second unbalanced horizontal force F4 of each pier is less than the corresponding horizontal force limit value F3;

[0036] S543, when the second unbalanced horizontal force F4 of each pier is less than the corresponding horizontal force limit F3, it is determined that the demolition condition is safe and step S55 is continued.

[0037] In one embodiment, the step S55 specifically includes the following steps:

[0038] S551, along the direction from the first main arch segment to the first side arch segment, there are four first side arch rings, first remove the second first side arch ring, and then remove the remaining first side arch rings in sequence from the second first side arch ring to both sides;

[0039] S552: There are twelve second side arch rings along the direction from the second main arch section to the second side arch section. The fifth second side arch ring is first removed, and then the remaining second side arch rings are removed in sequence from the fifth second side arch ring to both sides.

[0040] In one embodiment, the step S542 further includes the following steps:

[0041] S544, when the second unbalanced horizontal force F4 of each pier is less than the corresponding horizontal force limit value F3, it is determined that the demolition working condition is dangerous, the anti-overturning coefficient of the pier and the anti-slip coefficient of the pier base under the current working condition are calculated, and it is determined whether the pier is in a safe working condition under the current working condition according to the anti-overturning coefficient and the anti-slip coefficient;

[0042] S545, when the current working condition is a safe working condition, there are four first side arch rings along the direction from the first main arch segment to the first side arch segment, first remove the first arch rib on one side of the second first side arch ring, and then remove the first arch ribs on one side of the remaining first side arch rings in sequence from the second first arch rib to both sides;

[0043] S546, there are twelve second side arch rings along the direction from the second main arch segment to the second side arch segment, first remove the second arch rib on one side of the fifth second side arch ring, and then remove the second arch ribs on one side of the remaining second side arch rings in sequence from the removed second arch rib to both sides;

[0044] S547, referring to the removal steps from step S544 to step S546, remove the arch ribs on the other side of the first side arch ring and the second side arch ring.

[0045] In one embodiment, the step S544 further includes the following steps:

[0046] For the bridge piers after step S544, the following reinforcement measures are taken:

[0047] Diagonal braces are set on the outside of each pier to share the horizontal force of the pier;

[0048] Tie rods are set between adjacent piers to resist horizontal forces.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] The present application provides a method for dismantling a continuous multi-span arch bridge structure, and the dismantling of the arch bridge structure has the following steps: dismantling the first main bridge deck located in the first main arch section and the second main bridge deck located in the second main arch section; dismantling the longitudinal and transverse beams of the first main bridge and the first hanger assembly, the longitudinal and transverse beams of the second main bridge and the second hanger assembly, and retaining the first main arch ring and the second main arch ring; dismantling the first approach bridge deck and the second approach bridge deck; dismantling the first arch upper column assembly and the second arch upper column assembly, and retaining the first side arch ring and the second side arch ring; dismantling the first main arch ring, the second main arch ring, the first side arch ring and the second side arch ring; dismantling all bridge piers. Specifically, the main arch of the main bridge and the side arch of the approach bridge structure on which the present application relies are an organic whole. For this structure, the present application proposes a method for calculating the unbalanced horizontal force of the pier and obtaining the limit value of the horizontal force of the bridge dismantling, and inferring the order of bridge dismantling and reinforcement measures according to the calculated value of the unbalanced horizontal force, thereby improving the safety and stability of the bridge dismantling process, and having a certain applicability to arch bridge structures without unidirectional thrust piers and with small bridge pier stiffness. In addition, for some very old bridges, the construction process of the bridges is unclear due to incomplete data preservation and lack of a clear description of the bridge construction process. It is even more impractical to use conventional reverse methods to dismantle such bridges. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 the structures shown in these drawings without paying creative work.

[0052] Figure 1 is a schematic diagram of an arch bridge structure in an embodiment of the present application;

[0053] Figure 2 for Figure 1 A top view of the first main bridge deck and the second main bridge deck;

[0054] Figure 3 for Figure 1 Top view of the mid-arch bridge structure after the bridge deck is removed;

[0055] Figure 4 A schematic diagram of an arch bridge structure in an embodiment of the present application after removing other structures in the first main arch section and the second main arch section except the first main arch ring and the second main arch ring;

[0056] Figure 5 A schematic diagram of an arch bridge structure in an embodiment of the present application after removing other structures in the first side arch segment and the second side arch segment except the first side arch ring and the second side arch ring;

[0057] Figure 6 This is a schematic diagram of the structure of the arch bridge structure in one embodiment of the present application after the first main arch ring and the second main arch ring are removed;

[0058] Figure 7 A schematic diagram of using diagonal braces to reinforce bridge piers in one embodiment of the present application;

[0059] Figure 8 It is a schematic diagram of using tie rods to reinforce bridge piers in one embodiment of the present application;

[0060] Fig. 9 A flowchart of dismantling an arch bridge structure in one embodiment of the present application;

[0061] Fig.10 A flowchart of specific steps for removing the first main arch ring, the second main arch ring, the first side arch ring and the second side arch ring in one embodiment of the present application;

[0062] Fig.11 Flow chart for calculating the limit of horizontal force for bridge pier demolition.

[0063] Explanation of the reference numerals: 1. first main arch section; 11. first main arch ring; 12. first main bridge deck; 13. longitudinal and transverse beams of the first main bridge; 14. first hanger assembly; 2. second main arch section; 21. second main arch ring; 22. second main bridge deck; 23. longitudinal and transverse beams of the second main bridge; 24. second hanger assembly; 3. first side arch section; 31. first side arch ring; 311. first arch rib; 32. first arch upper column assembly; 33. first approach bridge deck; 4. second side arch section; 41. second side arch ring; 411. second arch rib; 42. second arch upper column assembly; 43. second approach bridge deck; 5. bridge pier; 6. diagonal brace; 7. tie rod. DETAILED DESCRIPTION

[0064] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0065] Furthermore, the technical solutions between the various embodiments of the present invention may be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in the field. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0066] When numerical ranges are given in the embodiments, it should be understood that unless otherwise specified in the present invention, both endpoints of each numerical range and any value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention are familiar to those skilled in the art and the description of the present invention, and any method, device and material of the prior art similar or equivalent to the method, device and material in the embodiments of the present invention can also be used to implement the present invention.

[0067] In common technology, the arch bridge structure is usually demolished by reverse construction, that is, the original construction steps are followed in the reverse order when the arch bridge structure is demolished. In general, a large one-way thrust pier is set every three to five arches to provide horizontal force for the remaining structure. Therefore, when dismantling the arch bridge structure, only the arch ring and the piers between the two thrust piers need to be considered. However, the project on which this application is based has a relatively small pier stiffness and no one-way thrust pier. At each step and each position of the bridge demolition, the stress of the entire arch bridge structure needs to be considered, and the arch bridge structure cannot be demolished by only using the reverse construction method.

[0068] The present invention provides a dismantling method applicable to a continuous multi-span arch bridge structure, comprising the following steps:

[0069] S1, dismantle the first main bridge deck 12 located at the first main arch section 1 and the second main bridge deck 22 located at the second main arch section 2; wherein the arch bridge structure comprises the first main arch section 1 and the second main arch section 2 connected along the longitudinal direction of the bridge, a plurality of first side arch sections 3 located at the side of the first main arch section 1, and a plurality of second side arch sections 4 located at the side of the second main arch section 2; wherein the first main arch section 1 comprises the first main arch ring 11, the first main bridge deck 12, the first main bridge longitudinal and transverse beams 13, and the first suspender assembly 14 for connecting the first main bridge longitudinal and transverse beams 13 and the first main arch ring 11, and the second main arch section 2 comprises the second main arch ring 21, the second main bridge deck 22, the second main bridge longitudinal and transverse beams 23, and the second suspender assembly 24 for connecting the second main bridge longitudinal and transverse beams 23 and the second main arch ring 21;

[0070] S2, dismantle the first main bridge longitudinal and transverse beam 13, the first suspension rod assembly 14, the second main bridge longitudinal and transverse beam 23, the second suspension rod assembly 24, and retain the first main arch ring 11 and the second main arch ring 21;

[0071] S3, dismantle all first approach bridge panels 33 located at the first side arch section 3 and all second approach bridge panels 43 located at the second side arch section 4; wherein each first side arch section 3 comprises a first side arch ring 31, a first arch upper column assembly 32 and a first approach bridge panel 33 laid on the top of the first arch upper column assembly 32, and each second side arch section 4 comprises a second side arch ring 41, a second arch upper column assembly 42 and a second approach bridge panel 43 laid on the top of the second arch upper column assembly 42;

[0072] S4, dismantle all the first arch upper column assemblies 32 and the second arch upper column assemblies 42, and keep all the first side arch rings 31 and the second side arch rings 41;

[0073] S5, dismantling the first main arch ring 11, the second main arch ring 21, the first side arch ring 31 and the second side arch ring 41;

[0074] S6, dismantle all bridge piers 5 to complete the dismantling of the arch bridge structure.

[0075] In the present application, please refer to Figures 1 to 9 First, dismantle the first main bridge deck 12 and the second main bridge deck 22 of the arch bridge structure, then dismantle the first main bridge longitudinal and transverse beam 13, the first hanger assembly 14 and the second main bridge longitudinal and transverse beam 23 and the second hanger assembly 24, and then dismantle the first approach bridge deck 33 and the second approach bridge deck 43, the first arch upper column assembly 32 and the second arch upper column assembly 42, and finally dismantle the first main arch ring 11, the second main arch ring 21 and the first side arch ring 31 and the second side arch ring 41. First remove the lighter structures such as the first main bridge deck 12, and then gradually dismantle the heavier components such as the first main arch ring 11, which helps to maintain the stability of the arch bridge structure until the bridge dismantling is completed, and can make the dismantling work more efficient.

[0076] In one embodiment, step S5 specifically includes the steps of:

[0077] S51, determining the maximum value of the unbalanced horizontal force of each pier 5 before the arch bridge structure is dismantled, and using the maximum value of the unbalanced horizontal force of each pier 5 as the bridge dismantling horizontal force limit value of the corresponding pier 5;

[0078] S52, calculating the unbalanced horizontal force for each bridge pier 5 after step S4, obtaining a first unbalanced horizontal force calculation value for each bridge pier 5, and determining whether the first unbalanced horizontal force calculation value for each bridge pier 5 is lower than the corresponding bridge demolition horizontal force limit value;

[0079] S53, when the calculated values ​​of the first unbalanced horizontal forces of all bridge piers 5 are lower than the corresponding bridge demolition horizontal force limit values, it is determined that the demolition working condition of the arch bridge structure is safe, and then the first main arch ring 11 and the second main arch ring 21 are synchronously demolished;

[0080] S54, performing unbalanced horizontal force calculation again on each bridge pier 5 after step S53, obtaining a second unbalanced horizontal force calculation value of each bridge pier 5, and determining whether the second unbalanced horizontal force calculation value of each bridge pier 5 is lower than the corresponding bridge demolition horizontal force limit value;

[0081] S55, when the calculated values ​​of the second unbalanced horizontal forces of all bridge piers 5 are lower than the corresponding bridge demolition horizontal force limit values, it is determined that the demolition working condition of the arch bridge structure is safe, and then the first side arch ring 31 and the second side arch ring 41 are demolished.

[0082] It should be explained that, in step S51, each bridge pier 5 has a maximum value of unbalanced horizontal force, and the maximum value of horizontal force of each bridge pier 5 is different. Therefore, the bridge demolition horizontal force limit value of each bridge pier 5 adopts the maximum value of unbalanced horizontal force of the bridge pier 5, and the bridge demolition horizontal force limit value of each bridge pier 5 is also different. In step S52, the calculated value of the first unbalanced horizontal force of each bridge pier 5 is also compared with the horizontal force limit value of the bridge pier 5.

[0083] In the embodiment of the present application, an unbalanced horizontal force is calculated for each pier 5, and the unbalanced horizontal force is compared with the horizontal force limit value, thereby determining whether the demolition condition of the arch bridge structure is safe, and then the first main arch ring 11, the second main arch ring 21, the first side arch ring 31 and the second side arch ring 41 are demolished. In this way, the first main arch ring 11, the second main arch ring 21, the first side arch ring 31 and the second side arch ring 41 can be safely demolished when the unbalanced horizontal force they are subjected to is lower than the demolition horizontal force limit value, and the unbalanced force of the arch bridge structure can be controlled to reduce the risk of continuous collapse of the arch bridge structure.

[0084] In one embodiment, step S51 specifically includes the following steps:

[0085] S511, calculating the horizontal force F1 borne by each pier 5 under the action of its own weight when the arch bridge structure is in a completed state;

[0086] S512, calculating the maximum horizontal force F2 borne by each pier 5 when the arch bridge structure is in operation;

[0087] S513, multiplying the horizontal force F1 and the maximum horizontal force F2 by their respective partial coefficients, combining and adding them, to obtain the horizontal force F3 borne by each pier 5, and using the horizontal force F3 corresponding to each pier 5 as the bridge demolition horizontal force limit corresponding to each pier 5.

[0088] It should be explained that the bridge dismantling horizontal force limit value of each bridge pier 5 in step S513 is different, and the horizontal force F3 corresponding to each bridge pier 5 is also different. For example, in this embodiment, for the bridge pier 5 at the junction of the first main arch ring 11 and the first side arch ring 31, it is calculated that the horizontal force F3 it bears is 7834 kN, so its bridge dismantling horizontal force limit value is also 7834 kN. During the bridge dismantling process, the unbalanced horizontal force borne by the bridge pier 5 at the junction of the first main arch ring 11 and the first side arch ring 31 cannot exceed 7834 kN.

[0089] In the embodiment of the present application, the horizontal force F3 corresponding to each pier 5 is calculated as the bridge demolition horizontal force limit corresponding to each pier 5, so that the pier 5 with a lower bridge demolition horizontal force limit can be found out, so that this type of pier 5 can be paid special attention to and protected, and the bridge demolition sequence can be designed with reference to the bridge demolition horizontal force limit in subsequent steps.

[0090] In one embodiment, the first side arch ring 31 includes four first arch ribs 311 arranged along the transverse bridge direction, and the second side arch ring 41 includes four second arch ribs 411 arranged along the transverse bridge direction, wherein:

[0091] Before the synchronous removal of the first main arch ring 11 and the second main arch ring 21 in step S53, the following steps are included:

[0092] First, two first arch ribs 311 located in the middle of the bridge in all first side arch rings 31 and two second arch ribs 411 located in the middle of the bridge in all second side arch rings 41 are removed, and then the first main arch ring 11 and the second main arch ring 21 are removed simultaneously.

[0093] It should be noted that the two first arch ribs 311 on the first side arch ring 31 located outside the bridge are opposite to the two arch ribs of the first main arch ring 11 , and the two second arch ribs 411 on the second side arch ring 41 located outside the bridge are opposite to the two arch ribs of the second main arch ring 21 .

[0094] In the embodiment of the present application, the two first arch ribs 311 located in the middle of the bridge in the first side arch ring 31 and the two second arch ribs 411 located in the middle of the bridge in all the second side arch rings 41 are first removed. This can reduce the probability that the first main arch ring 11 and the second main arch ring 21 and their corresponding piers 5 are subjected to forces exceeding the horizontal force limit of bridge demolition, reduce force imbalance, and improve the stability of the arch bridge structure during the bridge demolition process.

[0095] In one embodiment, removing the first arch rib 311 and the second arch rib 411 specifically includes the following steps:

[0096] Cut the two first arch ribs 311 located in the middle of the bridge in the first side arch ring 31 and the two second arch ribs 411 located in the middle of the bridge in the second side arch ring 41 longitudinally, and decompose the two first arch ribs 311 located in the middle of the bridge in the first side arch ring 31 and the two second arch ribs 411 located in the middle of the bridge in the second side arch ring 41;

[0097] The two first arch ribs 311 located in the middle of the bridge in the first side arch ring 31 and the two second arch ribs 411 located in the middle of the bridge in the second side arch ring 41 are removed by transverse segment cutting, and the first arch ribs 311 and the second arch ribs 411 located on the outside of the bridge in the first side arch ring 31 and the second side arch ring 41 are retained.

[0098] It should be noted that the two first arch ribs 311 in the middle of the bridge in the first side arch ring 31 are cast together with concrete, see Figure 3 When dismantling, the two first arch ribs 311 near the middle of the bridge need to be dismantled as a whole. In the schematic diagram, the two first arch ribs 311 near the middle of the bridge are represented as an integral structure. Figure 3 The first arch rib 311 represented by the box located in the middle of the bridge in the first side arch ring 31 on the far left is removed, and the same removal method is used for the two second arch ribs 411 located in the middle of the bridge in the second side arch ring 41.

[0099] In the embodiment of the present application, the two first arch ribs 311 located in the middle of the bridge in the first side arch ring 31 and the two second arch ribs 411 located in the middle of the bridge in the second side arch ring 41 are longitudinally cut, decomposed, and then transversely cut and removed in sections. The first arch ribs 311 and the second arch ribs 411 can be removed from the first side arch ring 31 and the second side arch ring 41 while maintaining the original state of the arch bridge structure as much as possible, thereby maintaining a stable stress state of the arch bridge structure.

[0100] In one embodiment, step S53 specifically includes the steps of:

[0101] S531, using a floating support platform device to dismantle the first main arch ring 11 and the second main arch ring 21; wherein the floating support platform device includes a floating vessel and a support working platform disposed on the floating vessel, and before dismantling the first main arch ring 11 and the second main arch ring 21, firstly fasten the support working platform and the first main arch ring 11 and the second main arch ring 21, and then use the support working platform to lift the first main arch ring 11 and the second main arch ring 21;

[0102] S532, cutting the first main arch ring 11 and the second main arch ring 21 from the arch foot position, and then cutting the first main arch ring 11 and the second main arch ring 21 in sections, and using the support working platform to carry the cut first main arch ring 11 and the second main arch ring 21;

[0103] S533, transporting the first main arch ring 11 and the second main arch ring 21 by using a floating ship.

[0104] It should be known that the floating support platform equipment is mainly composed of a floating boat and a support working platform. The floating boat floats on the water and serves as the basis of the support working platform. During the construction process, the support working platform can transfer the dead weight of the first main arch ring 11 and the second main arch ring 21 to the floating boat by fastening and lifting the first main arch ring 11 and the second main arch ring 21, and provide a working platform for cutting the first main arch ring 11 and the second main arch ring 21, and bear the weight of the first main arch ring 11 and the second main arch ring 21 which are disintegrated into multiple sections after cutting.

[0105] In the embodiment of the present application, the first main arch ring 11 and the second main arch ring 21 are removed by using a floating support platform device, and the first main arch ring 11 and the second main arch ring 21 can be cut from the arch foot at the same time and synchronously, and the first main arch ring 11 and the second main arch ring 21 are separated when the arch bridge structure is under force balance, so as to reduce the influence of the change of unbalanced force on the first side arch ring 31 and the second side arch ring 41 due to the removal of the first main arch ring 11 and the second main arch ring 21, and greatly reduce the influence of the unbalanced force on the pier 5 located between the first main arch ring 11 and the second main arch ring 21. The floating support platform device works directly on the water surface, is more flexible, and can adapt to various working conditions.

[0106] In one embodiment, step S54 specifically includes the steps of:

[0107] S541, simulating the bridge dismantling construction process, calculating the second unbalanced horizontal force F4 borne by each bridge pier 5 after step S53;

[0108] S542, determining whether the second unbalanced horizontal force F4 of each pier 5 is less than the corresponding horizontal force limit value F3;

[0109] S543, when the second unbalanced horizontal force F4 of each pier 5 is less than the corresponding horizontal force limit value F3, it is determined that the demolition condition is safe and step S55 is continued.

[0110] In the embodiment of the present application, the bridge dismantling construction process is simulated, the second unbalanced horizontal force F4 borne by the pier 5 after each step S53 is calculated, and F4 is compared with the horizontal force limit F3 to judge the safety status of the working condition, which can reduce the risk of continuous collapse of the arch bridge structure and improve the safety of subsequent steps.

[0111] In one embodiment, step S55 specifically includes the following steps:

[0112] S551, along the direction from the first main arch segment 1 to the first side arch segment 3, there are four first side arch rings 31, first remove the second first side arch ring 31, and then remove the remaining first side arch rings 31 in sequence from the second first side arch ring 31 to both sides;

[0113] S552, there are twelve second side arch rings 41 along the direction from the second main arch segment 2 to the second side arch segment 4, first remove the fifth second side arch ring 41, and then remove the remaining second side arch rings 41 in sequence from the fifth second side arch ring 41 to both sides.

[0114] It should be noted that the arch bridge structure has a first main arch ring 11, a second main arch ring 21, four first side arch rings 31 and twelve second side arch rings 41. The piers 5 are numbered from left to right, namely, the first to nineteenth piers 5, wherein the first to fifth piers 5 have four first side arch rings 31, the fifth to seventh piers 5 have the first main arch ring 11 and the second main arch ring 21, and the seventh to nineteenth piers 5 have twelve second side arch rings 41. According to the calculation of the second unbalanced horizontal force F4 borne by the piers 5, it can be known that the piers 5 with stronger bearing capacity are the first pier 5, the fifth pier 5, the seventh pier 5 and the nineteenth pier 5. In the process of dismantling the bridge, these piers 5 should be made to bear more horizontal forces and be left for the last dismantling. Among them, the bearing capacity of the first pier 5 is higher than that of the fifth pier 5, and the bearing capacity of the nineteenth pier 5 is higher than that of the seventh pier 5. Therefore, when dismantling the arch bridge structure, the first pier 5 and the nineteenth pier 5 should bear more horizontal forces generated by the first side arch ring 31 and the second side arch ring 41.

[0115] It needs to be explained that in step S55, before dismantling the first side arch ring 31 and the second side arch ring 41, there is a step of comparing the second unbalanced horizontal force calculation values ​​of all the piers 5 with the corresponding bridge demolition horizontal force limit values, that is, comparing the second unbalanced horizontal force calculation values ​​of all the piers 5 with their bridge demolition horizontal force limit values. Only when the second unbalanced horizontal force calculation values ​​of all the piers 5 are lower than their bridge demolition horizontal force limit values, can the demolition condition be determined to be safe.

[0116] Each pier 5 has a different ability to bear unbalanced horizontal forces. During the bridge dismantling process, the piers 5 that can bear higher unbalanced horizontal forces should be left for later dismantling. For example, in this embodiment, according to calculation, the bearing capacity of the first pier 5 and the fifth pier 5 in the first side arch ring 31 is relatively strong. Therefore, the third first side arch ring 31 between the first pier 5 and the fifth pier 5 is first dismantled, and then the remaining first side arch rings 31 are dismantled from the third first side arch ring 31 toward the direction of the first pier 5 and the fifth pier 5. The above method is also followed for the dismantling of the second side arch ring 41.

[0117] In the embodiment of the present application, along the direction from the first main arch section 1 to the first side arch section 3, the second first side arch ring 31 is first removed, and then the remaining first side arch rings 31 are removed in sequence on both sides along the second first side arch ring 31; along the direction from the second main arch section 2 to the second side arch section 4, the fifth second side arch ring 41 is first removed, and then the remaining second side arch rings 41 are removed in sequence on both sides from the fifth second side arch ring 41, so that the first side arch ring 31 and the second side arch ring 41 can be safely removed when the pier 5 is able to withstand the horizontal force of the first side arch ring 31 and the second side arch ring 41, thereby reducing the risk of continuous collapse of the arch bridge structure.

[0118] In one embodiment, step S542 further includes the following steps:

[0119] S544, when the second unbalanced horizontal force F4 of each pier 5 is less than the corresponding horizontal force limit value F3, it is determined that the demolition working condition is dangerous, the anti-overturning coefficient of the pier 5 and the anti-slip coefficient of the base of the pier 5 under the current working condition are calculated, and it is determined whether the pier 5 is in a safe working condition under the current working condition according to the anti-overturning coefficient and the anti-slip coefficient;

[0120] S545, when the current working condition is a safe working condition, there are four first side arch rings 31 along the direction from the first main arch segment 1 to the first side arch segment 3, first remove the first arch rib 311 on one side of the second first side arch ring 31, and then remove the remaining first arch ribs 311 on one side of the first side arch ring 31 in sequence from the second first arch rib 311 to both sides;

[0121] S546, there are twelve second side arch rings 41 along the direction from the second main arch segment 2 to the second side arch segment 4, first remove the second arch rib 411 on one side of the fifth second side arch ring 41, and then remove the second arch ribs 411 on one side of the remaining second side arch rings 41 in sequence from the removed second arch rib 41 to both sides;

[0122] S547 , referring to the removal steps from step S544 to step S546 , the ribs on the other side of the first side arch ring 31 and the second side arch ring 41 are removed.

[0123] It needs to be explained that the second unbalanced horizontal force F4 exerted on each pier 5 is different, and the horizontal force limit F3 is also different. Therefore, when judging the working condition, it is necessary to compare the second unbalanced horizontal force F4 exerted on each pier 5 with its horizontal force limit F3 to determine whether the working condition is safe.

[0124] In the embodiment of the present application, the first arch rib 311 on the side of the first side arch ring 31 and the second arch rib 411 on the side of the second side arch ring 41 are first removed, and then the first arch rib 311 and the second arch rib 411 on the other side are removed. The horizontal force F4 borne by the pier 5 during the bridge dismantling process is half of the original one, which is less than the horizontal force limit F3. In this way, the first arch ring and the second arch ring can be safely dismantled, thereby improving the safety of the bridge dismantling process.

[0125] In one embodiment, step S544 further includes the following steps:

[0126] For the bridge pier 5 after step S544, the following reinforcement measures are taken:

[0127] A diagonal brace 6 is arranged on the outside of each pier 5 to share the horizontal force of the pier 5;

[0128] Tie rods 7 are arranged between adjacent bridge piers 5 to resist horizontal forces.

[0129] In the embodiment of the present application, a diagonal brace 6 is provided on the outer side of the pier 5 and a tie rod 7 is provided between adjacent piers 5 , which can increase the stability of the pier 5 and enable the pier 5 to withstand a greater horizontal force.

[0130] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for dismantling a continuous multi-span arch bridge structure, characterized in that: The following steps are involved: S1, dismantle the first main bridge deck located at the first main arch section and the second main bridge deck located at the second main arch section; wherein the arch bridge structure comprises the first main arch section and the second main arch section connected along the longitudinal direction of the bridge, a plurality of first side arch sections located at the sides of the first main arch section, and a plurality of second side arch sections located at the sides of the second main arch section; wherein the first main arch section comprises the first main arch ring, the first main bridge deck, the first main bridge longitudinal and transverse beams, and the first suspender assembly for connecting the first main bridge longitudinal and transverse beams and the first main arch ring, and the second main arch section comprises the second main arch ring, the second main bridge deck, the second main bridge longitudinal and transverse beams, and the second suspender assembly for connecting the second main bridge longitudinal and transverse beams and the second main arch ring; S2, dismantling the first main bridge longitudinal and transverse beams, the first hanger assembly, the second main bridge longitudinal and transverse beams, and the second hanger assembly, and retaining the first main arch ring and the second main arch ring; S3, dismantling all first approach bridge panels located at the first side arch section and all second approach bridge panels located at the second side arch section; wherein each of the first side arch sections comprises a first side arch ring, a first arch column assembly, and a first approach bridge panel laid on top of the first arch column assembly, and each of the second side arch sections comprises a second side arch ring, a second arch column assembly, and a second approach bridge panel laid on top of the second arch column assembly; S4, removing all first arch upper column assemblies and second arch upper column assemblies, and retaining all first side arch rings and second side arch rings; S5, removing the first main arch ring, the second main arch ring, the first side arch ring, and the second side arch ring; S6, dismantling all bridge piers to complete the dismantling of the arch bridge structure; The step S5 specifically includes the following steps: S51, determining the maximum value of the unbalanced horizontal force of each pier of the arch bridge structure before demolition, and using the maximum value of the unbalanced horizontal force of each pier as the bridge demolition horizontal force limit value of the corresponding pier; S52, calculating the unbalanced horizontal force for each bridge pier after step S4, obtaining a first unbalanced horizontal force calculation value for each bridge pier, and determining whether the first unbalanced horizontal force calculation value for each bridge pier is lower than a corresponding bridge demolition horizontal force limit value; S53, when the calculated values ​​of the first unbalanced horizontal forces of all bridge piers are lower than the corresponding bridge demolition horizontal force limit values, it is determined that the demolition working condition of the arch bridge structure is safe, and then the first main arch ring and the second main arch ring are synchronously demolished; S54, performing unbalanced horizontal force calculation again on each bridge pier after step S53, obtaining a second unbalanced horizontal force calculation value of each bridge pier, and determining whether the second unbalanced horizontal force calculation value of each bridge pier is lower than the corresponding bridge demolition horizontal force limit value; S55, when the calculated values ​​of the second unbalanced horizontal force on all bridge piers are lower than the corresponding bridge demolition horizontal force limit values, it is determined that the demolition working condition of the arch bridge structure is safe, and then the first side arch ring and the second side arch ring are demolished.

2. The method for dismantling a continuous multi-span arch bridge structure according to claim 1, characterized in that: The step S51 specifically includes the following steps: S511, calculating the horizontal force F1 borne by each of the bridge piers under the action of its own weight when the arch bridge structure is in a completed state; S512, calculating the maximum value F2 of the horizontal force borne by each of the piers when the arch bridge structure is in operation; S513, multiplying the horizontal force F1 and the maximum horizontal force F2 by their respective partial coefficients, combining and adding them, to obtain the horizontal force F3 borne by each pier, and using the horizontal force F3 corresponding to each pier as the bridge demolition horizontal force limit corresponding to each pier.

3. The method for dismantling a continuous multi-span arch bridge structure according to claim 1, characterized in that: The first side arch ring includes four first arch ribs arranged along the transverse bridge direction, and the second side arch ring includes four second arch ribs arranged along the transverse bridge direction, wherein: Before the synchronous removal of the first main arch ring and the second main arch ring in step S53, the following steps are included: First, remove the two first arch ribs located in the middle of the bridge in all the first side arch rings and the two second arch ribs located in the middle of the bridge in all the second side arch rings, and then simultaneously remove the first main arch ring and the second main arch ring.

4. The method for dismantling a continuous multi-span arch bridge structure according to claim 3, characterized in that: The removal of the first arch rib and the second arch rib specifically comprises the following steps: Cutting longitudinally the two first arch ribs located in the middle of the bridge in the first side arch ring and the two second arch ribs located in the middle of the bridge in the second side arch ring, decomposing the two first arch ribs located in the middle of the bridge in the first side arch ring and the two second arch ribs located in the middle of the bridge in the second side arch ring; The two first arch ribs in the first side arch ring located in the middle of the bridge and the two second arch ribs in the second side arch ring located in the middle of the bridge are removed by transverse segment cutting, and the first arch rib and the second arch rib located on the outside of the bridge in the first side arch ring and the second side arch ring are retained.

5. The method for dismantling a continuous multi-span arch bridge structure according to claim 1, characterized in that: The step S53 specifically includes the following steps: S531, using a floating support platform device to dismantle the first main arch ring and the second main arch ring; wherein the floating support platform device comprises a floating vessel and a support working platform disposed on the floating vessel, and before dismantling the first main arch ring and the second main arch ring, firstly fasten the support working platform and the first main arch ring and the second main arch ring, and then use the support working platform to lift the first main arch ring and the second main arch ring; S532, cutting the first main arch ring and the second main arch ring from the arch foot position, and then cutting the first main arch ring and the second main arch ring in sections, and using the support working platform to carry the cut first main arch ring and the second main arch ring; S533: Use the floating vessel to transport the first main arch ring and the second main arch ring.

6. The method for dismantling a continuous multi-span arch bridge structure according to claim 3, characterized in that: The step S54 specifically includes the following steps: S541, simulating the bridge dismantling construction process, calculating the second unbalanced horizontal force F4 borne by each bridge pier after step S53; S542, determining whether the second unbalanced horizontal force F4 of each pier is less than the corresponding horizontal force limit value F3; S543, when the second unbalanced horizontal force F4 of each pier is less than the corresponding horizontal force limit F3, it is determined that the demolition condition is safe and step S55 is continued.

7. The method for dismantling a continuous multi-span arch bridge structure according to claim 6, characterized in that: The step S55 specifically includes the following steps: S551, along the direction from the first main arch segment to the first side arch segment, there are four first side arch rings, first remove the second first side arch ring, and then remove the remaining first side arch rings in sequence from the second first side arch ring to both sides; S552: There are twelve second side arch rings along the direction from the second main arch section to the second side arch section. The fifth second side arch ring is first removed, and then the remaining second side arch rings are removed in sequence from the fifth second side arch ring to both sides.

8. The method for dismantling a continuous multi-span arch bridge structure according to claim 6, characterized in that: The step S542 further includes the following steps: S544, when the second unbalanced horizontal force F4 of each pier is less than the corresponding horizontal force limit value F3, it is determined that the demolition working condition is dangerous, the anti-overturning coefficient of the pier and the anti-slip coefficient of the pier base under the current working condition are calculated, and it is determined whether the pier is in a safe working condition under the current working condition according to the anti-overturning coefficient and the anti-slip coefficient; S545, when the current working condition is a safe working condition, there are four first side arch rings along the direction from the first main arch segment to the first side arch segment, first remove the first arch rib on one side of the second first side arch ring, and then remove the first arch ribs on one side of the remaining first side arch rings in sequence from the second first arch rib to both sides; S546, there are twelve second side arch rings along the direction from the second main arch segment to the second side arch segment, first remove the second arch rib on one side of the fifth second side arch ring, and then remove the second arch ribs on one side of the remaining second side arch rings in sequence from the removed second arch rib to both sides; S547, referring to the removal steps from step S544 to step S546, remove the arch ribs on the other side of the first side arch ring and the second side arch ring.

9. The method for dismantling a continuous multi-span arch bridge structure according to claim 8, characterized in that: The step S544 further includes the following steps: For the bridge piers after step S544, the following reinforcement measures are taken: Diagonal braces are set on the outside of each pier to share the horizontal force of the pier; Tie rods are set between adjacent piers to resist horizontal forces.

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