Newly-built abutment structure based on existing line roadbed and construction method of newly-built abutment structure

Abstract

The invention provides a newly-built bridge abutment structure based on an existing line roadbed and a construction method thereof, and relates to the technical field of bridge engineering, the bridge abutment structure comprises the existing line roadbed, a newly-built pile foundation, a newly-built bridge abutment, a newly-built T beam, an abutment top plate and a butt strap behind the abutment. The newly-built pile foundations are arranged in the existing line roadbed, the tops of the pile foundations are the same in height, and the newly-built bridge abutment is installed above the pile foundations. The side wall of the end of the newly-built T-beam is matched with the side wall of the bridge abutment. The construction method comprises the steps of obtaining existing line foundation information, constructing the supporting piles, pouring the concrete top beams, installing the steel corbels, excavating a foundation pit, pouring a bridge abutment pile foundation, pouring abutment body concrete, installing a bridge abutment top plate and a butt strap behind the abutment, and finally completing construction of a newly-built bridge abutment. Under the condition that safe operation of the existing line is met, the bridge abutment reconstruction efficiency and the structural stability of the existing line roadbed are effectively improved, and the aim of newly building a bridge structure in situ under the operation condition is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge engineering, and in particular to a new abutment structure based on an existing line foundation and a construction method thereof. Background Art

[0002] As the existing railways age, some existing railway bridges can no longer meet the requirements of railway capacity expansion, high-speed train operation, speed increase and upgrade, so these existing railway bridges need to be renovated. In the process of renovation, some specific reconstruction problems will be encountered, especially when new construction or reconstruction projects are carried out on the existing line foundation. How to optimize and upgrade the bridge structure while ensuring uninterrupted line operation has become an urgent problem to be solved in the engineering community.

[0003] In the prior art, when reconstructing existing bridges, it is usually necessary to reconstruct the lines on a large scale, which not only consumes a lot of manpower and material resources, but also causes a lot of environmental problems such as new land acquisition and new demolition. In addition, traditional construction methods often have disadvantages such as long construction period and high cost. Not using the existing bridge substructure under the condition of in-situ reconstruction, but using staggered piers to build new ones is a new development trend in the reconstruction of existing bridges. Its core lies in achieving the goal of building new abutments in situ under the condition of existing line operation.

[0004] In order to solve the problem of building a new abutment in an existing line bed under the condition of existing line operation, a new abutment structure based on the existing line bed and a construction method thereof are urgently needed. Summary of the invention

[0005] The purpose of the present invention is to provide a construction method for a new abutment based on an existing line foundation to improve the above problems. In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] In the first aspect, the present application provides a new abutment structure based on an existing line bed, characterized in that it includes: an existing line bed, a new pile foundation, a new abutment, a new T-beam, an abutment top plate and a rear abutment plate, wherein the new pile foundation is arranged in the existing line bed, and the new pile foundation is provided with at least four new pile foundations, and the upper top height of each new pile foundation is the same; the new abutment is arranged directly above the new pile foundation; the new T-beam is arranged on the new abutment, and the end side wall plane of the new T-beam is arranged to fit with the side wall of the new abutment; the abutment top plate is arranged directly above the new abutment; the rear abutment plate is arranged directly above the existing line bed, and the end of the rear abutment plate is arranged on the abutment top plate.

[0007] In a second aspect, the present application also provides a construction method for a new abutment structure based on an existing line foundation, which is characterized by comprising:

[0008] Obtain structural information of existing line foundation;

[0009] Based on the structural information of the line foundation, a preset number of support piles are constructed on both sides of the existing abutment, and a concrete cap beam is poured on the upper top surface of the support piles, wherein the concrete cap beam is pre-embedded with a corbel anchor bar;

[0010] installing a steel corbel between the existing abutment and the concrete cap beam;

[0011] Based on the existing roadbed information, a construction beam of a preset length along the track direction is constructed on both sides of the existing roadbed, and the roadbed fill of the existing roadbed is excavated to obtain a roadbed pit of a preset height;

[0012] In the road foundation pit at a preset height below the construction temporary beam, excavation of the foundation pit, pouring of pile foundation of the new bridge abutment and pouring of concrete of the bridge abutment body are sequentially performed to obtain a newly poured bridge abutment;

[0013] The transition section is tamped in the roadbed pit behind the newly constructed bridge abutment, and concrete is poured within a 2m high range on the top of the roadbed to obtain a completed bridge abutment cone;

[0014] An abutment top plate is installed on the upper top surface of the newly built abutment, and a rear slab is set above the roadbed pit at the preset height. The existing abutments, exposed parts of the supporting piles and existing steel beams are dismantled in turn, a new T-beam structure is re-erected, ballast and tracks are laid, and a new bridge is obtained.

[0015] The beneficial effects of the present invention are:

[0016] The newly built abutment structure based on the existing line bed and the construction method thereof of the present invention significantly improve the stability and durability of the structure, while optimizing the use of materials and reducing resource waste. By setting support columns in the existing line bed, adopting the drilling and grouting method for construction, pre-processing and constructing temporary beams, prefabricating the platform top plate and the rear slab, etc., fast and efficient construction is achieved, minimizing the impact on traffic. In addition, through precise connection technology and L-shaped abutment design, it adapts to different terrains and space limitations and improves environmental adaptability. The construction method of the present invention is not only technologically innovative, but also maximizes cost-effectiveness while ensuring construction safety. In addition, the present invention broadens the scope of application of the existing overhead line system and can be applied to strata with high groundwater levels and strong permeability.

[0017] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or be understood by implementing the embodiments of the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 It is a right side schematic diagram of a newly built abutment structure based on an existing line foundation according to an embodiment of the present invention;

[0020] Figure 2 It is a front view schematic diagram of a newly built abutment structure based on an existing line foundation according to an embodiment of the present invention;

[0021] Figure 3 It is a schematic flow chart of a construction method for a new abutment based on an existing line foundation described in an embodiment of the present invention.

[0022] In the figure: 1. Existing line foundation; 2. New pile foundation; 3. New abutment; 4. New T-beam; 5. Abutment top plate; 6. Abutment back slab. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0024] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0025] Embodiment 1:

[0026] This embodiment provides a new abutment structure based on an existing line foundation.

[0027] See also Figure 1 and Figure 2, the figure shows a newly built abutment structure, including an existing line bed 1, a newly built pile foundation 2, a newly built abutment 3, a newly built T-beam 4, an abutment top plate 5 and a rear abutment plate 6, the newly built pile foundation 2 is arranged in the existing line bed 1, and the newly built pile foundation 2 is provided with at least four piles, and the upper top height of each newly built pile foundation 2 is the same; the newly built abutment 3 is arranged directly above the newly built pile foundation 2; the newly built T-beam 4 is arranged on the newly built abutment 3, and the end side wall plane of the newly built T-beam 4 is arranged to fit with the side wall of the newly built abutment 3; the abutment top plate 5 is arranged directly above the newly built abutment 3; the rear abutment plate 6 is arranged directly above the existing line bed 1, and the end of the rear abutment plate 6 is arranged on the abutment top plate 5.

[0028] It can be understood that the newly built abutment structure of the present invention ensures the balance and stability of the structure by evenly arranging at least four newly built pile foundations 2 in the existing line bed 1, and the height consistency of the top of each pile foundation further enhances the overall symmetry. The newly built abutment 3 is located directly above the pile foundation and is closely combined with the newly built T-beam 4, ensuring the effective transfer of the load and the smoothness of the track. The setting of the abutment top plate 5 not only improves the bearing capacity of the structure, but also provides convenience for construction and maintenance. The rear slab 6 serves as a transition part with the existing line bed 1, which helps to evenly distribute the load and reduce the impact on the existing structure. Overall, the present invention shows significant beneficial effects in improving structural stability, optimizing load distribution, enhancing construction efficiency, improving environmental adaptability and reducing maintenance costs, and has achieved a technical breakthrough in the construction or reconstruction of bridge structures.

[0029] Wherein, the newly built abutment 3 is configured to be L-shaped.

[0030] It can be understood that the L-shaped setting of the newly built abutment 3 improves spatial adaptability and allows more efficient use of space in limited or complex terrain; enhances structural stability, especially providing a larger support area and better resistance when subjected to lateral force or torque; optimizes load distribution and extends the service life of the bridge; improves construction convenience and provides more operating space for construction personnel and equipment; improves aesthetics and makes the bridge more harmonious with the surrounding environment; provides scalability to facilitate possible structural expansion or modification in the future; enhances safety and provides higher safety performance under earthquakes or extreme weather conditions; and reduces maintenance costs and reduces maintenance needs due to stress concentration.

[0031] The thickness of the platform top plate 5 is 0.3m-1m, the thickness of the platform rear plate 6 is 15cm-20cm, and the length is greater than or equal to 6.5m.

[0032] It is understandable that the size design of the platform top plate 5 and the platform back plate 6 comprehensively considers structural safety, economy, construction convenience, load distribution, adaptability, maintenance simplicity, aesthetics and environmental adaptability. This design not only ensures sufficient strength and rigidity to bear the expected load, but also reduces costs through the rational use of materials, while facilitating construction and maintenance. In addition, the length and thickness of the platform back plate provide good adaptability and flexibility to adapt to different installation environments, and the overall size design also takes into account the aesthetics of the bridge and the performance stability under different environmental conditions, wherein the length of the platform back plate 6 is greater than or equal to the roadbed excavation length.

[0033] Embodiment 2:

[0034] like Figure 3 As shown, this embodiment provides a construction method for a new abutment structure based on an existing line foundation, see Figure 3 , the figure shows that the construction method includes step S1, step S2, step S3, step S4, step S5, step S6 and step S7.

[0035] Step S1, obtaining structural information of the existing line foundation;

[0036] Step S2, constructing a preset number of support piles on both sides of the existing abutment based on the structural information of the line foundation, and pouring concrete cap beams on the upper top surfaces of the support piles, wherein the concrete cap beams are pre-embedded with corbel anchor bars;

[0037] Step S3, installing a steel corbel between the existing abutment and the concrete cap beam;

[0038] Step S4: constructing a construction beam of a preset length along the track direction in the existing line foundation based on the existing roadbed information, and removing the roadbed fill of the existing roadbed to obtain a roadbed pit of a preset height;

[0039] Step S5, excavating the foundation pit, pouring the pile foundation of the new abutment and pouring the concrete of the abutment body are sequentially performed in the road foundation pit at a preset height below the construction temporary beam to obtain a newly poured abutment;

[0040] Step S6, tamping the transition section in the roadbed pit behind the newly constructed bridge abutment, and pouring concrete within a 2m high range on the top of the roadbed to obtain a completed bridge abutment cone;

[0041] Step S7, installing an abutment top plate on the upper top surface of the newly built abutment, and setting a rear slab above the roadbed pit at the preset height, dismantling the existing abutments, the exposed parts of the supporting piles and the existing steel beams in turn, re-erecting a new T-beam structure, laying ballast and tracks, and obtaining a newly built bridge.

[0042] It can be understood that the construction method enhances the stability and bearing capacity of the new structure by accurately obtaining the existing line foundation structural information; strengthens the integrity and connection firmness of the structure by orderly constructing support piles, concrete crown beams and steel corbels; effectively maintains traffic and creates construction conditions by using construction beams; achieves rapid construction through continuous earth excavation, pile foundation pouring and concrete pouring; and after the new abutment is poured, efficiently installs the top plate and slab, dismantles the old structure and re-erects the new steel beam to restore the integrity and functionality of the bridge. This process not only improves construction efficiency and ensures construction safety, but also effectively controls costs by optimizing material use and construction processes, while minimizing the impact on the environment, providing an innovative, efficient and safe bridge construction solution, wherein the structural information of the line foundation includes information such as existing abutment structure information, existing steel beam structure information, existing abutment cone structure information, existing roadbed information and geological conditions information.

[0043] Wherein, step S2 includes step S21.

[0044] Step S21, the support piles are constructed by drilling and grouting method, wherein the straight-line distance between the support piles and the center line of the existing abutment structure is greater than or equal to 4.5 m.

[0045] It can be understood that this step realizes effective support for the construction of temporary beams by constructing support piles through the bored cast-in-place method, while ensuring the safety of construction and the reliability of the new structure. Maintaining a sufficient distance also helps to reduce the negative impact that may be caused to the existing structure during construction, such as foundation settlement or structural displacement. More importantly, this distance can meet the requirements of the bored cast-in-place pile construction technology under the operating conditions of the existing line, avoiding the construction risks caused by the use of the more backward bored pile technology and its inapplicability to high groundwater levels and highly permeable formations. In addition, this method also improves construction efficiency, shortens the construction period, and lays a solid foundation for the smooth completion of the entire bridge construction project.

[0046] Wherein, step S3 includes step S31 and step S32.

[0047] Step S31, partially chiseling away the existing abutment to obtain an installation space of the same size as one end of the steel corbel;

[0048] Step S32, fixedly connecting one end of the steel corbel to the corbel anchor bar.

[0049] It can be understood that this step realizes the rapid conversion of the existing line support system from the existing abutment to the construction beam, effectively ensuring the operational safety of the existing line. This connection method realizes the requirement of rapid structural installation under the condition of being close to the existing line, and avoids the impact on the operational safety of the existing line after the existing abutment is partially removed. At the same time, this process also helps to shorten the construction period, improve construction efficiency, and create conditions for the smooth progress of subsequent construction steps.

[0050] Wherein, step S4 includes step S41, step S42 and step S43.

[0051] Step S41, pre-processing the construction beam to obtain the construction beam to be assembled;

[0052] Step S42, assembling the pre-processed construction beams vertically on both sides of the track along the track direction, wherein the construction beams directly above the existing abutments are arranged directly above the steel corbels;

[0053] Step S43, excavating the topsoil on the upper surface of the existing roadbed directly below the construction temporary beam, wherein the excavation depth is 2m downward from the top of the existing roadbed.

[0054] It can be understood that this step provides a safe, efficient and stable construction environment for the construction of new abutment structures through the use of prefabricated construction beams, precise settings and necessary roadbed excavation, while ensuring the safety and continuity of existing line operations.

[0055] Wherein, step S5 includes step S51.

[0056] Step S51, the total height of the newly cast abutment is 6.35m, and the length of the abutment body is 2.5m.

[0057] It can be understood that this step ensures the stability and bearing capacity of the abutment and the existing line support structure by setting the appropriate height and length of the newly built abutment.

[0058] Wherein, step S7 includes step S71, step S72 and step S73.

[0059] Step S71, prefabricating a platform top plate in a factory, wherein the factory prefabricated platform top plate includes a concrete shear key;

[0060] Step S72, arranging a 50mm diameter steel rod above the abutment, wherein a shear keyway is reserved and a 3cm M50 dry hard mortar cushion is used for leveling;

[0061] Step S73, the prefabricated platform top plate is installed on the upper top surface of the mortar cushion layer for fixation, the steel rods and shear key grooves are inserted and filled with grouting material.

[0062] It can be understood that this step ensures the size and quality accuracy of the abutment top plate through factory prefabrication. The use of steel bars, concrete shear keys and grouting materials improves the connection stability between the abutment top plate and the abutment structure. The use of prefabricated components avoids the spatial interference between the D-type construction beam and the abutment top surface, reduces on-site construction time and labor requirements, and improves construction efficiency and project quality.

[0063] Wherein, step S7 also includes step S74 and step S75.

[0064] Step S74, putting up the board behind the prefabricated platform in the factory;

[0065] Step S75, setting a rear platform board above the roadbed pit at the preset height, wherein the end of the rear platform board is fixedly connected to the platform top plate.

[0066] It can be understood that this step improves the overall stability and durability of the bridge structure by fixing the rear slab to the top slab. The design and installation of the rear slab helps to evenly distribute the load in the rear embankment, reduce the pressure on the embankment soil, and help to greatly reduce the uneven settlement problem of the later embankment transition section.

[0067] It should be noted that, regarding the device in the above embodiment, the specific manner in which each module performs the operation has been described in detail in the embodiment of the method, and will not be elaborated here.

[0068] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0069] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A new abutment structure based on an existing line foundation, characterized in that: include: Existing line foundation (1); A new pile foundation (2) is built, the new pile foundation (2) is arranged in the existing line foundation (1), at least four new pile foundations (2) are arranged, and the top height of each new pile foundation (2) is the same; A newly built abutment (3), wherein the newly built abutment (3) is arranged directly above the newly built pile foundation (2); A newly built T-beam (4), wherein the newly built T-beam (4) is arranged on the newly built abutment (3), and the end side wall plane of the newly built T-beam (4) is arranged to fit with the side wall of the newly built abutment (3); A top plate (5), the top plate (5) being arranged directly above the newly built abutment (3); A rear platform board (6) is provided just above the existing line foundation (1), and an end of the rear platform board (6) is provided on the platform top plate (5).

2. The newly constructed abutment structure based on the existing line foundation according to claim 1 is characterized in that: The newly built abutment (3) is configured to be L-shaped.

3. The newly constructed abutment structure based on the existing line foundation according to claim 1 is characterized in that: The thickness of the platform top plate (5) is 0.3m-1m, the thickness of the platform rear plate (6) is 15cm-20cm, and the length is greater than or equal to 6.5m.

4. A construction method for a new abutment structure based on an existing line foundation, characterized in that: include: Obtain structural information of existing line foundation; Based on the structural information of the line foundation, a preset number of support piles are constructed on both sides of the existing abutment, and a concrete cap beam is poured on the upper top surface of the support piles, wherein the concrete cap beam is pre-embedded with a corbel anchor bar; installing a steel corbel between the existing abutment and the concrete cap beam; Based on the existing roadbed information, a construction beam of a preset length along the track direction is constructed on both sides of the existing roadbed, and the roadbed fill of the existing roadbed is excavated to obtain a roadbed pit of a preset height; In the road foundation pit at a preset height below the construction temporary beam, excavation of the foundation pit, pouring of pile foundation of the new bridge abutment and pouring of concrete of the bridge abutment body are sequentially performed to obtain a newly poured bridge abutment; The transition section is tamped in the roadbed pit behind the newly constructed bridge abutment, and concrete is poured within a 2m high range on the top of the roadbed to obtain a completed bridge abutment cone; An abutment top plate is installed on the upper top surface of the newly built abutment, and a rear slab is set above the roadbed pit at the preset height. The existing abutments, exposed parts of the supporting piles and existing steel beams are dismantled in turn, a new T-beam structure is re-erected, ballast and tracks are laid, and a new bridge is obtained.

5. The construction method of a new abutment structure based on an existing line foundation according to claim 4 is characterized in that , constructing a preset number of support piles on both sides of the existing abutment based on the existing abutment structure information, and pouring concrete cap beams on the upper top surfaces of the support piles, including: The support piles are constructed by drilling and grouting method, wherein the straight-line distance between the support piles and the center line of the existing abutment structure is greater than or equal to 4.5 m.

6. The construction method of a new abutment structure based on an existing line foundation according to claim 4, characterized in that , installing a steel corbel between the existing abutment and the concrete cap beam, including: Partially chiseling away the existing abutment to obtain an installation space of the same size as one end of the steel corbel; One end of the steel corbel is fixedly connected to the corbel anchor bar.

7. The construction method of a new abutment structure based on an existing line foundation according to claim 4, characterized in that , based on the existing roadbed information, constructing a construction beam of a preset length along the track direction on both sides of the existing roadbed, and excavating the roadbed fill of the existing roadbed, including: Pre-processing the construction beams to obtain construction beams to be assembled; Assembling the pre-processed construction beams vertically on both sides of the track along the track direction, wherein the construction beams at the existing abutments are arranged directly above the steel corbels; Topsoil excavation is performed on the upper surface of the existing roadbed directly below the construction beam, wherein the excavation depth is 2 m downward from the top of the existing roadbed.

8. The construction method of a new abutment structure based on an existing line foundation according to claim 4, characterized in that , in the road foundation pit at a preset height below the construction beam, excavation of the foundation pit, pouring of the pile foundation of the new abutment and pouring of the concrete of the abutment body are carried out in sequence to obtain the poured new abutment, including: The total height of the newly cast abutment is 6.35m, and the length of the abutment body is 2.5m.

9. The construction method of a new abutment structure based on an existing line foundation according to claim 4, characterized in that , installing abutment top plate on the upper top surface of the newly built abutment, including: A factory-fabricated deck top slab, wherein the factory-fabricated deck top slab comprises concrete shear keys; A 50mm diameter steel rod is arranged above the abutment, wherein a shear key slot is reserved and a 3cmM50 dry hard mortar cushion is used for leveling; The prefabricated platform top plate is installed on the upper top surface of the mortar cushion layer for fixing, and the steel rods and shear key grooves are inserted and filled with grouting material.

10. The construction method of a new abutment structure based on an existing line foundation according to claim 4, characterized in that , and set up a rear slab above the roadbed pit at the preset height, including: The board is erected behind the prefabricated platform in the factory; A rear platform board is arranged above the roadbed pit of the preset height, wherein the end of the rear platform board is fixedly connected to the platform top plate.

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