A lifting structure and lifting method for a concrete bridge across waters

Abstract

The present application relates to a lifting structure and a lifting method for a concrete bridge across waters, which is used to lift the pier of the bridge, wherein the pier includes two upper and lower sections, and the section section has a first tooth structure, which includes: an extended concrete block, wherein the upper and lower end faces of the extended concrete block are provided with a plurality of anti-shear tooth blocks, and the upper end face of the extended concrete block and the anti-shear tooth blocks thereon, and the lower end face of the extended concrete block and the anti-shear tooth blocks thereon, respectively form a second tooth structure for meshing with the first tooth structure; an extended steel bar, which vertically penetrates the extended concrete block and is used to connect with the reserved steel bars of the upper and lower sections of the pier. The second tooth structure meshes with the first tooth structure on the section of the upper and lower sections of the pier, making it difficult for the connection to be displaced in the horizontal direction, and making the lifting structure tightly combined with the original pier, meeting the requirements of the shear resistance and bearing capacity of the lifting structure.

Description

Technical Field

[0001] The present application relates to the field of bridge reinforcement design and construction, and in particular to a lifting structure and a lifting method for a concrete bridge across water areas. Background Art

[0002] With the changes in the environment or shipping needs, many cross-water bridges cannot meet the needs of flood control or navigation, and need to be comprehensively upgraded and renovated to raise the superstructure of the bridge.

[0003] In some related technologies, the main construction method for bridge elevation is to use the broken column elevation method, that is, to use a floor bracket or a column as a platform for construction, cut the bridge pier on the construction platform, and use a jacking device to support and jack up the cap beam and the bridge superstructure at the upper end of the cut part; then re-extend and cast the cut part to achieve bridge elevation; but there are the following problems:

[0004] (1) When pouring the extension, the upper and lower end surfaces of the pier cut are usually roughened, and vertical steel bars and stirrups are tied at the same time, and finally ordinary concrete is poured. This structure and its construction method have the problem of loose bonding between the new and old concrete, which makes the extension pouring difficult, resulting in insufficient shear resistance and bearing capacity of the extended pier, and a safety hazard to the structure.

[0005] (2) As most bridges are located in water-spanning areas, ground supports or columns are used as construction platforms, which makes it difficult to set up construction platforms. Summary of the invention

[0006] The embodiments of the present application provide a lifting structure and a lifting method for a concrete bridge across water areas, so as to solve the problem in the related art that the concrete lifting structure is not tightly connected, resulting in insufficient shear resistance and bearing capacity of the extended bridge piers.

[0007] In a first aspect, a lifting structure for a concrete bridge across a water area is provided, which is used to lift a pier of the bridge, wherein the pier includes two upper and lower segments, and the segment section has a first tooth structure, which includes:

[0008] The extended concrete block has a plurality of anti-shear tooth blocks on both upper and lower end surfaces, and the upper end surface of the extended concrete block and the anti-shear tooth blocks thereon, as well as the lower end surface of the extended concrete block and the anti-shear tooth blocks thereon, each form a second tooth structure for meshing with the first tooth structure;

[0009] The extension steel bar is vertically passed through the extension concrete block and is used to connect with the reserved steel bars of the upper and lower sections of the pier.

[0010] In some embodiments, the extended steel bar passes through the anti-shear tooth block, or the extended steel bar passes through the gaps between a plurality of the anti-shear tooth blocks.

[0011] In some embodiments, the anti-shear tooth block is a conical protrusion, and the cross-sectional area of ​​the anti-shear tooth block gradually decreases from an end of the anti-shear tooth block close to the extended concrete block to an end of the anti-shear tooth block away from the extended concrete block.

[0012] In some embodiments, the anti-shear tooth blocks are distributed in multiple rows, and the anti-shear tooth blocks in each row are evenly spaced; the anti-shear tooth blocks in two adjacent rows are staggered.

[0013] In a second aspect, a method for raising a concrete bridge across a water area is provided, comprising the following steps:

[0014] Cutting the bridge pier into two upper and lower segments, and forming a first meshing structure on the cross section of the segment;

[0015] The upper segment of the two segments is moved to the designed elevation so as to form a casting space between the upper and lower segments;

[0016] In the pouring space, the reserved steel bars on the upper and lower segments are extended by using the extended steel bars;

[0017] Concrete is poured in the pouring space to form an elevated structure of a concrete bridge across a water area.

[0018] In some embodiments, before cutting the pier portion into the upper and lower segments, the following steps are further included:

[0019] When a cap beam is supported on the pier, a clamping platform is arranged at the lower side of the cutting position of the pier, and a jacking device is arranged on the clamping platform to jack up the cap beam; otherwise, a clamping platform is arranged on both the upper and lower sides of the cutting position of the pier, and a jacking device is arranged on the clamping platform located at the lower side to jack up the clamping platform located at the upper side.

[0020] In some embodiments, the hoop platform includes a concrete hoop and embedded reinforcement, and forming the hoop platform includes the following steps:

[0021] Determine the height of the concrete hoop according to the frictional resistance between the concrete hoop and the bridge pier, and the number of embedded reinforcement bars, and manufacture the concrete hoop;

[0022] Roughening the inner surface of the concrete hoop and the surface of the pier in contact with the concrete hoop;

[0023] The embedded reinforcement bars are evenly arranged along the circumference of the pier to connect the concrete hoop and the pier.

[0024] In some embodiments, the concrete hoop is formed by enclosing a plurality of arc-shaped concrete blocks and is disposed around the pier.

[0025] In some embodiments, the first tooth structure is formed by chiseling the cross section of the segment using a pneumatic pick or a water jet machine.

[0026] In some embodiments, after the extension of the extension steel bar and before pouring concrete, the method for raising the cross-water concrete bridge further includes:

[0027] Strain gauges are installed on the extended steel bars to monitor their stress conditions.

[0028] The beneficial effects of the technical solution provided by this application include:

[0029] An embodiment of the present application provides an elevated structure for a concrete bridge across water areas. Since the elevated structure includes an extended concrete block, shear-resistant tooth blocks distributed at the upper and lower ends of the extended concrete block, and extended steel bars, when in use, the upper and lower end faces of the extended concrete block and the shear-resistant tooth blocks thereon form a second tooth structure, and the second tooth structure meshes with the first tooth structure on the cross-section of the upper and lower sections of the pier, making it difficult for the connection to be displaced in the horizontal direction, and making the elevated structure tightly combined with the original pier, meeting the requirements of shear resistance and bearing capacity of the connection between the extended concrete block and the original pier; and the extended steel bars pass through the extended concrete block and are connected to the reserved steel bars to further strengthen the connection, thereby making the elevated structure tightly combined with the pier. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 A schematic diagram of the longitudinal structure of the bridge when the entire bridge is raised according to an embodiment of the present application;

[0032] Figure 2 A schematic diagram of the longitudinal structure of the bridge when the entire bridge is raised according to an embodiment of the present application (a cross-sectional view in the direction of AA);

[0033] Figure 3 A schematic diagram of a lifting structure provided in an embodiment of the present application;

[0034] Figure 4 Provided in the embodiments of this application Figure 3Cross-section along the middle BB direction;

[0035] Figure 5 A schematic cross-sectional view of the clamp platform provided in an embodiment of the present application.

[0036] In the figure: 1. Extended concrete block; 2. Shear tooth block; 3. Extended steel bar; 4. Segment; 5. Hoop platform; 50. Concrete hoop; 51. Embedded reinforcement; 6. Cap beam; 7. Jacking device; 8. Bridge superstructure; 9. Horizontal plane; 10. Strain gauge; 11. Casting space. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0038] The embodiment of the present application provides an elevated structure for a concrete bridge across water areas, which can solve the problem in the related art that the concrete elevated structure is not tightly connected, resulting in insufficient shear resistance and bearing capacity of the extended bridge piers.

[0039] See also Figure 1-Figure 4 A lifting structure for a concrete bridge across a water area, which is used to lift a bridge pier, the pier includes two upper and lower segments 4, and each segment 4 has a first tooth structure on its cross section, which includes an extended concrete block 1, an anti-shear tooth block 2 and an extended steel bar 3, the anti-shear tooth block 2 is arranged on the upper and lower end faces of the extended concrete block 1, the upper end face of the extended concrete block 1 and the anti-shear tooth block 2 thereon, as well as the lower end face of the extended concrete block 1 and the anti-shear tooth block 2 thereon, each form a second tooth structure for meshing with the first tooth structure;

[0040] The extension steel bar 3 is vertically passed through the extension concrete block 1 and is used to connect with the reserved steel bars on the upper and lower sections 4 of the pier.

[0041] Through the above structural setting, when in use, the upper and lower sections of the extended concrete block 1 and the shear-resistant tooth blocks 2 thereon form a second meshing structure, which meshes with the first meshing structure on the sections of the upper and lower segments 4 of the pier, so that a meshing meshing structure is formed at the connection between the elevated structure and the pier. The meshing structure makes it difficult for the elevated structure to be displaced in the horizontal direction, and increases the area of ​​the combination between the elevated structure and the original pier, making the combination tighter, thereby meeting the requirements of shear resistance and bearing capacity at the connection between the extended concrete block 1 and the original pier.

[0042] In some preferred embodiments, the distribution positions of the extension steel bars 3 and the anti-shear tooth blocks 2 are as follows:

[0043] First, the extension steel bar 3 is passed through the extension concrete block 1 and the anti-shear tooth block 2 at the same time. Furthermore, the extension steel bar 3 is passed through along the central axis of the anti-shear tooth block 2, that is, the extension steel bar 3 extends from the center of the top of the anti-shear tooth block 2. This arrangement enhances the structural stability of the anti-shear tooth block 2.

[0044] Second, if Figure 3 As shown, the extended steel bars 3 pass through the gaps between the multiple anti-shear tooth blocks 2 and are evenly spaced apart from the anti-shear tooth blocks 2; the gaps can be the gaps between two adjacent anti-shear tooth blocks 2 among the anti-shear tooth blocks 2 evenly distributed in a straight line; or the gaps enclosed between the anti-shear tooth blocks 2 distributed in a ring shape, which can also cooperate with the first meshing structure to play a role in strengthening the connection.

[0045] like Figure 3 and Figure 4 As shown, in some preferred embodiments, the anti-shear tooth block 2 is a conical protrusion, and a plurality of inclined surfaces are provided on the conical protrusion. The cross-sectional area of ​​the anti-shear tooth block 2 gradually decreases from one end of the anti-shear tooth block 2 close to the extended concrete block 1 to the end away from the extended concrete block 1, so that the connection between the anti-shear tooth block 2 and the extended concrete 1 becomes stable.

[0046] A plurality of anti-shear tooth blocks 2 are distributed in multiple rows, and the anti-shear tooth blocks 2 in each row are evenly spaced; the anti-shear tooth blocks 2 in two adjacent rows are staggered to increase the shear resistance of the connection between the anti-shear tooth blocks 2 and the extended concrete 1.

[0047] The anti-shear tooth blocks 2 on the upper and lower end faces of the extended concrete block 1 are mirror-imaged, that is, symmetrically distributed, or complementarily arranged. Through the above structural setting, multiple anti-shear tooth blocks 2 are staggered to increase the shear resistance and the overall stability of the connection with the first meshing structure.

[0048] Furthermore, the extension concrete block 1 and the shear-resistant tooth block 2 are both UHPC concrete. UHPC has the advantages of high compressive and shear strengths, and its structural bearing capacity is high, which enhances the stability of the lifting structure.

[0049] In some preferred implementations, the diameter of the extended concrete block 1 is the same as the diameter of the upper and lower segments 4 of the pier, and has the same cylindrical structure as the pier, so that the raised structure is consistent with the upper and lower segments of the pier, forming a good transition, not protruding outward, and without a gap in between, thereby facilitating the application of protective agent at the extended part of the bridge pier after elevation; on the other hand, it has a certain aesthetic appeal.

[0050] See also Figure 1-5A method for raising a concrete bridge across a water area, characterized in that it comprises the following steps:

[0051] The bridge pier is cut into two upper and lower segments 4, and a first meshing structure is formed on the cross section of the segment 4;

[0052] The upper segment 4 of the two segments 4 is moved to the design elevation, so that a casting space 11 is formed between the upper and lower segments 4; wherein the design elevation is the elevation of the position where the bridge superstructure 8 is to be raised;

[0053] In the pouring space 11, the reserved steel bars on the upper and lower sections 4 are extended by using the extended steel bars 3;

[0054] UHPC concrete is poured in the pouring space 11 to form an elevated structure of a concrete bridge across a water area.

[0055] Through the above method, the present elevated structure is quickly formed, so that the elevated structure formed by casting is closely combined with the bridge pier.

[0056] In some preferred implementations, new vertical steel bars, namely, extension steel bars 3, are processed and manufactured, and both ends of the extension steel bars 3 are respectively welded to the reserved steel bars after the piers are chiseled out, and the welding length is not less than 10 times the diameter of the steel bars.

[0057] In some preferred implementations, before cutting the bridge pier portion into the upper and lower segments 4, the following steps are also included:

[0058] When cutting a bridge with a cap beam 6 and a bridge superstructure 8 supported on the piers, it is necessary to first set a clamping platform 5 on the lower side of the cutting position, and set a jacking device 7 on the clamping platform 5 to jack up the cap beam 6.

[0059] When cutting a bridge supporting a bridge superstructure 8 on a bridge pier, it is necessary to first set a clamping platform 5 on both the upper and lower sides of the cutting position, and set a jacking device 7 on the clamping platform 5 on the lower side to jack up the clamping platform 5 on the upper side.

[0060] The above two types of hoop platforms 5 can be used for bridges across waters or on foundations without columns, such as Figure 1 and Figure 2 As shown, when a part of the bridge pier is located below the horizontal plane 9, it is difficult to erect a floor stand or column as a construction platform. Therefore, a clamping platform 5 is directly set on the bridge pier to facilitate construction, reduce construction costs, and shorten the construction period.

[0061] like Figure 5 As shown, in some preferred embodiments, the hoop platform 5 includes a concrete hoop 50 and a reinforcing bar 51, and forming the hoop platform 5 includes the following steps:

[0062] Determine the height of the concrete hoop 50 according to the frictional resistance between the concrete hoop 50 and the bridge pier, and the number of the embedded steel bars 51, and determine the thickness of the concrete hoop 50 according to the diameter of the jacking device 7, and manufacture the concrete hoop 50;

[0063] The inner surface of the concrete hoop 50 and the surface of the pier in contact with the concrete hoop 50 are respectively roughened with an electric pick to form a roughened surface;

[0064] The embedded steel bars 51 are evenly arranged along the circumference of the bridge pier to connect the concrete hoop 50 and the bridge pier. The depth of the embedded steel bars 51 is not less than ten times the diameter of the embedded steel bars 51 .

[0065] Furthermore, the height of the concrete hoop 50 is calculated by the following formula:

[0066] γV≤μf c ×h×C+0.5f gj ×A gj

[0067] Where γ is the structural safety factor. Since the structure is a temporary structure, the coefficient is taken as 2.0; V is the design value of the 50° vertical force of the concrete hoop; μ is the static friction coefficient of the concrete of the pier; f c is the lower strength of the concrete hoop 50 and the bridge pier; h is the vertical height of the concrete hoop 50; C is the circumference of the bridge pier; f gj A is the tensile strength of the embedded steel bar 51; gj is the total cross-sectional area of ​​the embedded reinforcement 51; in addition, to ensure the safety of the structural force, the vertical height h of the concrete hoop 50 is not less than 0.5m.

[0068] Furthermore, to facilitate the installation of the concrete hoop 50, the concrete hoop 50 is formed by a plurality of arc-shaped concrete blocks and is arranged around the pier; one end of the embedded reinforcement 51 is connected to the concrete hoop 50, and the other end is used to implant the segment 4 so that the concrete hoop 50 is fixed on the segment 4.

[0069] Further, the first tooth structure is formed by chiseling the section of segment 4 by a pneumatic pick or a water jet machine, and the shear resistance calculation is performed on the first tooth structure; the first tooth structure is the section of segment 4 and the conical convex block that is the same as the shear resistance tooth block 2, and the reserved steel bars pass through the conical convex block, and the number of conical convex blocks is not less than five; the shear resistance calculation of the conical convex block can be based on the interface being borne only by concrete without considering the effect of steel bars, and the specific formula is as follows:

[0070]

[0071] Where Q his the transverse shear design value of the lifting structure; γ is the safety factor of the lifting structure, μ is the static friction coefficient of the concrete of the pier; σ n is the vertical stress of the pier; A d is the cross-sectional area of ​​the raised structure; f is the number reduction factor of the conical bumps; f ck is the standard value of compressive strength of the pier; A j It is the total root area of ​​the tapered boss.

[0072] In some preferred implementations, the lifting device 7 includes a hydraulic system, a computer control system, a hydraulic jack, a displacement and pressure sensor, etc. The system sets the number of lifting jacks, the jack pressure, stroke, load, etc. through computer control; the number of jacks is determined according to the weight of the cap beam 6 and the bridge superstructure 8, and is symmetrically and evenly arranged on the hoop platform 5. At the same time, the lifting device 7 can control the displacement of multiple jacks for synchronous lifting, and the displacement accuracy is ±0.5mm.

[0073] In some preferred implementations, the extension steel bars 3 are arranged in an array, and after the extension steel bars 3 are extended and before the concrete is poured, the lifting method further comprises:

[0074] Strain gauges 10 are installed on the extended steel bars 3 to monitor the stress conditions of the extended steel bars 3 and other parts at various stages of the bridge raising construction.

[0075] Furthermore, a strain gauge 10 is provided on each of the extended steel bars 3 distributed in an array, and the strain gauges 10 are evenly and symmetrically distributed along the circumferential direction of the pier, so that the pressure monitored by the strain gauges 10 is more accurate.

[0076] In some preferred implementations, UHPC ultra-high performance concrete is used for pouring and filling when pouring concrete; UHPC has the advantages of high compressive and shear strength and high structural bearing capacity; in addition, the material is fluid, which is convenient for construction and helps to ensure the pouring density of the extended structure.

[0077] See also Figure 1 and Figure 5 A construction device for an elevated structure of a concrete bridge across water areas includes a hoop platform 5 and a plurality of jacking devices 7. The hoop platform 5 is used to be arranged on the upper and lower segments 4 of a bridge pier. The jacking devices 7 are installed on the hoop platform 5 located on the lower segment 4 and jack up the hoop platform 5 located on the upper segment, so as to form a casting space 11 for accommodating the elevated structure of the concrete bridge across water areas between the upper and lower segments 4.

[0078] Through the setting of the above structure, a construction platform can be set up directly on the bridge piers, avoiding the defect of setting up a construction platform to cut and raise the bridge under cross-water conditions or foundation conditions where columns cannot be installed. Construction can be carried out directly on the bridge piers. As a construction platform, its installation and construction costs are low and its scope of application is relatively wide.

[0079] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0080] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0081] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A lifting structure for a concrete bridge across a water area, which is used to lift a bridge pier of the bridge, wherein the bridge pier comprises two upper and lower segments (4), and the cross section of the segment (4) has a first tooth structure, characterized in that: It includes: The extended concrete block (1) has a plurality of anti-shear tooth blocks (2) on both upper and lower end surfaces, and the upper end surface of the extended concrete block (1) and the anti-shear tooth blocks (2) thereon, as well as the lower end surface of the extended concrete block (1) and the anti-shear tooth blocks (2) thereon, each form a second tooth structure for meshing with the first tooth structure; Extension steel bars (3) are vertically inserted through the extension concrete block (1) and are used to connect with the reserved steel bars of the upper and lower sections (4) of the pier; The extended steel bar (3) passes through the anti-shear tooth block (2), or the extended steel bar (3) passes through the gaps between a plurality of the anti-shear tooth blocks (2); The anti-shear tooth blocks (2) are distributed in multiple rows, and the anti-shear tooth blocks (2) in each row are evenly spaced; the anti-shear tooth blocks (2) in two adjacent rows are staggered; The anti-shear tooth blocks (2) on the upper and lower end surfaces of the extended concrete block (1) are distributed in mirror images of each other; The diameter of the extended concrete block (1) is the same as the diameter of the upper and lower sections (4) of the bridge pier, and is a cylindrical structure similar to that of the bridge pier.

2. The elevated structure of a water-spanning concrete bridge as claimed in claim 1, characterized in that: The anti-shear tooth block (2) is a conical protrusion, and the cross-sectional area of ​​the anti-shear tooth block (2) gradually decreases from one end of the anti-shear tooth block (2) close to the extended concrete block (1) to one end away from the extended concrete block (1).

3. A method for raising a concrete bridge across a water area, characterized in that: The following steps are involved: Cutting the bridge pier into two upper and lower segments (4), and forming a first meshing tooth structure on the cross section of the segment (4); The upper segment (4) of the two segments (4) is moved to the designed elevation so that a casting space (11) is formed between the upper and lower segments (4); In the pouring space (11), the reserved steel bars on the upper and lower segments (4) are extended by using the extending steel bars (3); Concrete is poured in the pouring space (11) to form the elevated structure of the water-spanning concrete bridge as claimed in claim 1.

4. The method for raising a concrete bridge across a water area as claimed in claim 3, characterized in that: Before the pier portion is cut into two upper and lower segments (4), the following steps are also included: When a cap beam (6) is supported on the pier, a hoop platform (5) is arranged at the lower side of the cutting position of the pier, and a jacking device (7) is arranged on the hoop platform (5) to jack up the cap beam (6); otherwise, a hoop platform (5) is arranged on both upper and lower sides of the cutting position of the pier, and a jacking device (7) is arranged on the hoop platform (5) located at the lower side to jack up the hoop platform (5) located at the upper side.

5. The method for raising a water-spanning concrete bridge according to claim 4, characterized in that: The hoop platform (5) comprises a concrete hoop (50) and a reinforcing bar (51), and forming the hoop platform (5) comprises the following steps: Determining the height of the concrete hoop (50) according to the frictional resistance between the concrete hoop (50) and the bridge pier, and the number of the embedded steel bars (51), and manufacturing the concrete hoop (50); The inner surface of the concrete hoop (50) and the surface of the pier in contact with the concrete hoop (50) are respectively roughened; The embedded reinforcement bars (51) are evenly arranged along the circumference of the pier to connect the concrete hoop (50) and the pier.

6. The method for raising a water-spanning concrete bridge as claimed in claim 5, characterized in that: The concrete hoop (50) is formed by enclosing a plurality of arc-shaped concrete blocks and is arranged around the bridge pier.

7. The method for raising a water-spanning concrete bridge as claimed in claim 3, characterized in that: The first tooth structure is formed by chiseling the cross section of the segment (4) using a pneumatic pick or a water jet machine.

8. The method for raising a concrete bridge across a water area as claimed in claim 3, characterized in that: After the extension steel bar (3) is extended and before the concrete is poured, the method for raising the water-spanning concrete bridge further comprises: Strain gauges (10) are installed on the extended steel bars (3) to monitor their stress conditions.

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