Bridge jacking steel embrace column beam construction method and device

Abstract

This invention discloses a construction method and apparatus for bridge jacking steel column pier beams, addressing the problems of unreliable installation, weak shear resistance, and low construction efficiency in existing steel column pier beam technologies. The apparatus includes a shear key and a steel column pier beam. The steel column pier beam is a ring-shaped body composed of multiple segments spliced ​​end-to-end. A shear key, a rectangular thick steel plate, is vertically installed and its end furthest from the steel column pier beam is a fixed end, embedded and fixed within a slot in the pier column. This apparatus is simple, quick, and recyclable. The steel column pier beam is prefabricated in a factory, shortening the on-site construction period.

Description

Technical Field

[0001] This invention relates to the field of bridge jacking construction technology, and in particular to a steel column-clamping beam device and construction method. Background Technology

[0002] Lifting construction technology is an emerging technique in bridge engineering construction. Specifically, it involves raising and adjusting the height of a bridge through jacking operations to meet the planning and construction requirements of the bridge project. Furthermore, bridge jacking can save manpower, material resources, and financial resources in bridge reconstruction construction and reduce the impact on the normal operation of the bridge, demonstrating significant advantages. Therefore, it has a wide range of applications in bridge reconstruction construction.

[0003] In bridge jacking construction technology, the tie beam is a commonly used reaction system formed by binding the original pier with the original column. Its principle is to transfer the jacking force through the tie beam, raising the entire bridge to the designated height. Therefore, the tie beam is the core load-bearing component in bridge jacking construction, and thus it needs to have sufficient rigidity and strength to ensure the safety of the jacking operation.

[0004] Depending on their structure, column-supporting beams can be divided into concrete column-supporting beams and steel column-supporting beams.

[0005] Currently, concrete column-supporting beams are often used in bridge jacking construction. These beams provide sufficient shear force through the interface friction between the old and new concrete and the reinforcing steel.

[0006] The construction process of steel column beams is complex, the construction period is long, the demolition is difficult and has a significant impact on the environment. In addition, the friction between the new and old concrete interfaces is low.

[0007] Steel column-mounted beams are generally fixed using tie bolts or brackets, which connect the column-mounted beam to the pier body.

[0008] To address the aforementioned problems or drawbacks, this invention develops a convenient and efficient device and method for lifting steel column beams for bridges. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this invention provides a method and apparatus for constructing bridge jacking steel column beams, which solves the problems of unreliable installation, weak shear resistance, and low construction efficiency of existing steel column beams.

[0010] The technical solution adopted by this invention to solve its technical problem is as follows:

[0011] A method for constructing a bridge jacking steel column-mounted beam, characterized by the following steps performed in sequence:

[0012] Step 1: Cut concrete around the pier column to form a groove, which consists of horizontal and vertical sections;

[0013] Step 2: Place the shear key vertically in the vertical part of the slot, and place the reinforcing bar through the shear key in the horizontal part of the slot. Spot weld the reinforcing bar to the original reinforcing bar of the pier column. The shear key is a rectangular thick steel plate, and the shear key is provided with reserved holes for the reinforcing bar to pass through and bolt holes for matching with the steel column beam.

[0014] Step 3: Pour high-strength concrete into the groove, smooth the outer surface, and cure until hardened;

[0015] Step 4: Secure the bolt holes on the shear keys to the steel column beam one by one using high-strength bolts and nuts;

[0016] Step 5: Connect the ends of adjacent steel column beams around the pier.

[0017] Step six: Place the lifting jacks between the steel column beam and the bridge to lift the bridge and extend the piers. After the bridge is lifted into place and the piers are extended, dismantle the steel column beam in reverse order of steps four and five, following the principle of installation before dismantling.

[0018] Furthermore, in steps one and two, stirrup slots are cut between adjacent slots to prevent stirrups from forming. The stirrups are welded to the reinforcing bars of the shear key to form a whole.

[0019] Furthermore, the end of the shear key near the pier is an inclined surface, a toe plate is welded to the inclined surface of the shear key, the vertical surface where the slot is located is a wedge-shaped surface, the wedge-shaped surface has an inclination from top to bottom and from inside to outside, and the toe plate and the wedge-shaped surface are wedge-shaped fit.

[0020] Further, proceed with the following steps in sequence:

[0021] Step 1: Cut concrete around the pier column to form a groove, which consists of horizontal and vertical sections;

[0022] Step 2: Fix the embedded part in the slot of the pier column. The embedded part is an open box-shaped structure composed of two side plates, three horizontal plates and one back plate, with an inner cavity. One horizontal plate is provided with a groove, which is located near the back plate. The column is locked in the inner cavity. The steel bars passing through the embedded part are placed in the horizontal part of the slot and spot welded to the original steel bars of the pier column. High-strength concrete is poured into the slot, the outer surface is smoothed, and cured until hardened.

[0023] Step 3: Install the shear key. The shear key is a rectangular steel plate with at least a number of L-shaped grooves and a protrusion. Push the upper edge of the shear key horizontally along the upper edge of the inner cavity of the embedded part, and move it from top to bottom after it is inserted to the bottom. During the movement from top to bottom, the protrusion is embedded in the groove, and the locking pin is embedded in the groove at the same time. Then, insert a wedge into the upper cavity of the shear key.

[0024] Step 4: Secure the bolt holes on the shear keys to the steel column beam one by one using high-strength bolts and nuts;

[0025] Step 5: Connect the ends of adjacent steel column beams around the pier.

[0026] Step six: Place the lifting jacks between the steel column beam and the bridge to lift the bridge and extend the piers. After the bridge is lifted into place and the piers are extended, dismantle the steel column beam in reverse order of steps three, four and five, following the principle of installation before dismantling. Finally, remove the shear keys.

[0027] A bridge jacking steel column-hugging beam device, characterized in that it includes a shear key and a steel column-hugging beam, wherein...

[0028] The steel column-mounted beam is a ring-shaped structure composed of multiple segments spliced ​​together end to end, and...

[0029] The shear key, which is a rectangular thick steel plate, is fastened to the steel column beam by high-strength bolts and is installed vertically. The end of the shear key away from the steel column beam is the fixed end, which is embedded in and fixed in the slot of the pier column.

[0030] Furthermore, the fixed end includes a toe plate disposed on the shear key, and the toe plate is inclined relative to the pier column.

[0031] Furthermore, it also includes a wedge and an embedded part, wherein the embedded part has an inner cavity, a locking post and a groove, and multiple L-shaped grooves on the shear key are engaged with the locking post, the protrusion on the shear key is inserted into the groove, and the wedge is located above the shear key to limit the fixed shear key.

[0032] The beneficial effects of this invention are:

[0033] 1. The method of using the steel column lifting device for bridges described in this invention is simple, quick, and recyclable. The steel column beam is prefabricated in the factory, which can shorten the on-site construction period.

[0034] 2. Traditional concrete column-supporting beams primarily resist the jacking force during construction through the friction between the new and old concrete layers of the original pier column. However, the friction at the concrete interface is significantly affected by construction quality, and the interface friction per unit area of ​​the concrete column-supporting beam is low. Steel plates, on the other hand, have high shear stiffness. This invention uses slotted steel plates as shear keys, with through-reinforced bars within the shear keys, providing sufficient load-bearing capacity during jacking. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the steel column-mounted beam.

[0036] Figure 2 This is a schematic diagram of the entire concrete pier column;

[0037] Figure 3 This is a front view of a concrete pier column;

[0038] Figure 4 This is a schematic diagram of a shear key;

[0039] Figure 5 This is a side view diagram of the shear key installation;

[0040] Figure 6 This is a front view diagram of the shear key installation;

[0041] Figure 7 This is a schematic diagram showing the disassembly and assembly connection of the crossbeam and longitudinal beam of the column-supporting beam;

[0042] Figure 8 This is a schematic diagram of the connection between the horizontal beam and the longitudinal beam of the column-supporting beam;

[0043] Figure 9 This is a schematic diagram of the connection between the horizontal beam and the longitudinal beam of the column-supporting beam;

[0044] Figure 10 This is a diagram showing the installation and use of the shear key in Example 2.

[0045] Figure 11 It is an assembly drawing.

[0046] Figure 12 yes Figure 11 Sectional view A-A.

[0047] Figure 13 It is a 3D view of the embedded part.

[0048] Figure 14 This is a 3D diagram of a shear key.

[0049] Figure 15 This is a 3D view of a steel column-mounted beam (segment).

[0050] Figure 16 This is a schematic diagram of the pier slot.

[0051] Figure 17 This is the node diagram of Example 2.

[0052] Figure 18 This is a diagram of the nodes after demolition.

[0053] Figure 19 This is a schematic diagram of Example 3.

[0054] Figure 20 This is a perspective view of the shear key in Example 4.

[0055] Figure 21 This is the node diagram of Example 4.

[0056] In the diagram: 1 is the original concrete pier; 2 is the steel retaining beam; 3 is the shear key; 4 is the bolt hole; 5 is the reserved hole; 6 is the through reinforcement; 7 is high-strength concrete; 8 is the high-strength bolt and nut; 9 is the reserved operating hole; 10 is the top plate of the steel retaining beam; 11 is the bottom plate of the steel retaining beam; 12 is the beam end connecting steel plate; 13 is the web of the retaining beam; 14 is the stiffening rib; 15 is the thickened connecting plate of the retaining beam.

[0057] 11 wedge-shaped surface, 31 toe plate, 311 inclined plane,

[0058] 16 wedges, 17 embedded parts, 171 horizontal plate, 1711 groove, 172 back plate, 173 side plate, 1731 rebar perforation, 10' steel column beam, 3' shear key, 31' slot, 32' protrusion, 4' bolt hole, 6' rebar, 61' locking column, 8' high-strength bolts and nuts. Detailed Implementation

[0059] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0060] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0061] As described in the background section, bridge jacking is increasingly used in bridge reconstruction. However, the current method of using concrete column-supported beams for jacking involves long construction cycles, difficult demolition, and significant environmental impact. Furthermore, the low friction between the new and old concrete interfaces makes it difficult to guarantee construction quality. Therefore, the inventors have proposed an invention patent: a device and method for jacking steel column-supported beams for bridges.

[0062] Specific Implementation 1

[0063] A device for lifting steel column beams for bridges, such as Figures 1 to 6 As shown, this invention mainly consists of three parts: the first part is the steel column-hugging beam 2, a rectangular frame structure formed by welding steel plates, which is directly fastened to the shear key. During jacking, this steel column-hugging beam provides a force-bearing platform for the jacking system; the second part is the shear key 3, which is the main force-transmitting component, transferring the jacking force to the original bridge pier; the third part is the original bridge pier 1, a reinforced concrete pier used to securely install the shear key. The pier bears the shear force transmitted by the shear key. After the bridge jacking is completed, the steel column-hugging beam can be removed to allow for pier extension work.

[0064] Reference image, with Figure 1 For example, the pier is a square pier, and the steel column-hugging beam is a quadrilateral structure composed of multiple segments, which is built at a predetermined height on the pier through shear keys.

[0065] The piers can also be circular piers, vase-shaped piers, etc., and the outline of the corresponding steel column beams corresponds to the shape of the piers.

[0066] The aforementioned steel column-supporting beam is a box-section steel beam (the specific cross-sectional dimensions can be determined based on the pier column dimensions and jacking height), which is the main load-bearing component of the device. Its cross-section mainly consists of a top plate, a bottom plate, web stiffening ribs, and connecting steel plates, and is generally a welded component.

[0067] The steel column-hugging beam surrounds the original pier column and is as close to or nearly close to the pier column as possible. The steel column-hugging beam and the pier column are connected by shear keys to realize the pre-set design of the steel column-hugging beam.

[0068] The shear key 3 is embedded in the concrete pier column on one side (inner side), providing a secure and stable fixation. The other side (outer side) is fixed to the steel column beam using bolts. In this embodiment, the embedding refers to embedding to a certain depth, with the shear force generally occurring in the vertical direction.

[0069] The pier column is first slotted, and the shear key and reinforcing steel are fixed in the slot. Then, high-strength concrete is poured. This operation allows part of the shear key structure to be embedded and fixed in the pier column, making the shear key more secure.

[0070] During bridge jacking, the jacking force of the jacks is transmitted to the piers through shear keys. Therefore, there is a large shear force between the piers and the shear keys, and this shear force occurs in the main stress-bearing part of the shear keys. In order to ensure that the shear keys and concrete do not slip relative to each other under the action of shear force, the shear keys are cast on one side of the pier to prevent the steel bars from penetrating, thereby improving the shear strength.

[0071] Operation Example

[0072] To further illustrate the use of this device and method, the implementation method of the present invention will be described in more detail with reference to examples. The specific implementation steps are as follows:

[0073] Step 1, as follows Figure 2 As shown, firstly, a concrete cutter (cutting tool) is used to cut four slots of a specified size around the pier (reinforced concrete structure), evenly distributed on the four sides of the pier. Specifically, each slot consists of horizontal and vertical sections. The vertical section is used to install shear keys; that is, the vertical length of the vertical section is greater than the length of the shear key, used to fix the shear key and meet the installation requirements. There are two, or possibly three or four, horizontal sections, used to accommodate reinforcing bars 6. The presence of these reinforcing bars 6 enhances the anchorage strength of the shear keys in the pier, effectively preventing the shear keys from detaching.

[0074] Ideally, in this embodiment, the groove depth is 10 to 20 centimeters, and this groove depth can be configured according to the size of the pier column.

[0075] The aforementioned pier columns require symmetrical slotting on their sides to ensure the stability of the column-supporting beam under stress.

[0076] Furthermore, stirrup grooves are cut between adjacent slots. These stirrup grooves are used for the arrangement of stirrups. Specifically, the stirrups are set along the circumference of the pier column and effectively connected to the reinforcing bars in the shear keys, for example, by welding. The stirrups can effectively connect multiple shear keys located in different directions into a whole and form a ring-shaped reinforcing cage.

[0077] Step two, as Figure 2-4 As shown, a steel plate of a specified thickness, such as a preferred 20mm thick steel plate, is perforated and shaped as a rectangle. This thick steel plate is installed vertically and serves as the shear key 3, which is the main force-transmitting component during bridge jacking. Specifically, round holes are drilled at the pre-embedded locations of the thick steel plate to form reserved holes, through which reinforcing bars are threaded. A through-bar 6, embedded on one side of the pier 1, passes through the reserved hole 5 and is spot-welded to the existing reinforcing bars of the pier body, making it an integral part of the pier body and improving the shear strength of the structure.

[0078] Step 3: Pour high-strength concrete 7. After fixing the shear key 3 and the through steel bar 6, pour high-strength concrete 7 into the groove, smooth the outer surface, and wait for the high-strength concrete to reach the specified strength.

[0079] Step four, install steel column-mounted beam 2. (For example...) Figure 5 As shown, the pre-drilled bolt holes 4 on the shear key 3 are matched one by one with the holes on the steel column beam 2, and high-strength bolts and nuts 8 are used to fix them to ensure that the force on the steel column beam 2 is successfully transmitted to the shear key 3.

[0080] Step 5, as Figure 6 The longitudinal and transverse column-supporting beams 2 are connected and fixed end-to-end. The bolt holes at the ends of the steel column-supporting beams 2 are aligned one-to-one, and high-strength bolts and nuts 82 are used through the pre-drilled operating holes 9 to connect the longitudinal and transverse column-supporting beams into a single unit. To ensure sufficient local strength at the connection points, a thickened connecting steel plate 15 is added at the connection location of the column-supporting beam web 13, guaranteeing the structural safety and integrity. The final installation is illustrated in the diagram below. Figure 1 As shown, after installation, the shear key spans between the column beam and the pier.

[0081] Step six: Place the lifting jacks between the steel column beam and the bridge to lift the bridge and extend the piers. After the bridge is lifted into place and the piers are extended, dismantle the column beam in the reverse order of steps ④ and ⑤, following the principle of installation before dismantling.

[0082] Furthermore, in step one of the above methods, an operating slot is provided on the bottom plate or outer side of the steel column beam to facilitate the installation of bolts.

[0083] Furthermore, in step three of the above method, stiffening ribs are installed inside and outside the steel column beam to improve the overall strength of the column beam.

[0084] Furthermore, in step four of the above method, a thickened connecting plate is installed at the beam end connection position of the steel column-column beam to improve the strength of the connection position.

[0085] Specific Implementation Two

[0086] refer to Figures 10-17 This embodiment includes a shear key 3', a wedge 16, an embedded part 17, and a steel column beam 10'.

[0087] The embedded part 17 is an open box-shaped structure composed of two side plates 173, three horizontal plates 171, and a back plate 172, and has an internal cavity. One of the horizontal plates has a groove 1711 located near the back plate. Corresponding to the groove, seven pairs of steel bar through holes 1731 are arranged from top to bottom on the two side plates 173. Steel bars 6' are inserted into the through holes and welded in place, thus forming seven cylindrical locking posts 61' within the internal cavity of the embedded part. The internal cavity has a narrow width D and a long length L.

[0088] In this technology, the shear key 3' is a rectangular steel plate, on which multiple L-shaped grooves 31' are formed by wire cutting. These grooves extend inward from the edge of the rectangular steel plate, having both horizontal and vertical portions, and appear L-shaped when viewed from the side. The grooves 31' are quickly engaged with the aforementioned locking pin 61' by being inserted gradually from top to bottom and from the inside out. A protrusion 32' is located below the rectangular steel plate, forming a raised section, which is used to align the recess 1711 in the embedded part. The protrusion is inserted into the recess from top to bottom.

[0089] Wedge 16 is inserted above the shear key, that is, into the gap between the shear key and the inner cavity of the embedded part, to effectively fix the fixed shear key and limit and lock the shear key in the vertical direction.

[0090] A bolt hole 4' is provided on the shear key 3'. The bolt hole corresponds to the bolt hole on the vertical plate of the steel column beam and is connected using high-strength bolts and nuts 8'. After connection, the steel column beam is effectively connected to the pier column through the shear key, embedded parts and embedded parts.

[0091] The present invention also provides an installation method for a bridge jacking steel column beam device, the specific operation steps of which are as follows:

[0092] Step 1: Grooving the original pier: First, use a cutter to groove around the original pier.

[0093] Step 2, Fixing the shear key and reinforcing bar: Fix the embedded part in the slot of the pier column and pour high-strength concrete into the slot.

[0094] Step 3: Install the shear key. Push the upper edge of the shear key horizontally along the upper edge of the embedded part's inner cavity. After it reaches the bottom, move it downwards. During this downward movement, the protrusion engages in the groove, and the locking pin simultaneously engages in the slot. After the shear key has descended, insert a wedge (nylon or steel) into the upper cavity of the shear key. This wedge has a threaded hole for easy removal. This wedge is a precautionary measure, serving to limit the height of the shear key; excessively tight insertion is not required.

[0095] Step 4, install the steel column retaining beam: Connect the insertion interface of the steel column retaining beam to the shear key, and ensure that the bolt holes of the shear key fixing steel plate correspond one-to-one with the bolt holes of the shear key. Then, use high-strength bolts to fix the two together.

[0096] Step 5: Connect the longitudinal and transverse column beams: To ensure the integrity of the steel column beams, bolt holes are reserved in both the longitudinal and transverse column beams. During jacking, bolts are used to fix the ends of the longitudinal and transverse column beams to form a whole.

[0097] Step Six: After the bridge is jacked into place and the piers are heightened, following the principle of installation before removal, dismantle the column-supporting beams in the reverse order of Steps Four and Five. Finally, remove the shear key 3'. The result after dismantling is as follows: Figure 18 As shown, after removal, embedded part 17 is left on the pier body, and finally it can be smoothed with mortar.

[0098] Compared with Embodiment 1, this embodiment has the advantages of rapid installation and rapid dismantling. Furthermore, the shear keys and steel column beams in this embodiment can be reused after secondary relocation if they are found to be undamaged after visual inspection.

[0099] Specific Implementation Three

[0100] This embodiment provides an example of a method for constructing a steel column-mounted beam on a circular pier:

[0101] The difference between this embodiment and embodiments one and two is that the pier 1 in this embodiment is a cylindrical structure. (Refer to...) Figure 19 The corresponding steel column-mounted beam 2 is composed of multiple arc-shaped beams, which together form a complete steel column-mounted beam structure. The inner side is attached to the pier column. The rest, such as the shear key 3, the installation process and the dismantling process are basically the same or similar to the two embodiments mentioned above, and can be completed by experienced construction personnel.

[0102] Specific Implementation Four

[0103] This embodiment is an evolution based on Embodiment 1. Specifically, the shear key 3 in this embodiment is modified from the method of Embodiment 1. Specifically, the shear key in Embodiment 1 is a rectangular thick steel plate, while the shear key in this embodiment has a trapezoidal outline. That is, the rear end of the shear key, that is, the end closer to the pier, is a slope. Correspondingly, at the slot position on the pier where the installation point is located, the vertical surface of the slot is changed to a wedge-shaped surface 11. The wedge-shaped surface has a slope from top to bottom and from inside to outside. The shear key and the wedge-shaped surface are wedge-shaped and fit together. After the steel column beam is installed, the steel column beam applies downward compressive stress to the shear key. The applied compressive stress is distributed to the shear key 3. The shear key has a downward tendency relative to the pier. Under the action of this tendency, the steel column beam constrains the shear key upward and inward through bolts, so that the shear key is locked in the wedge-shaped space between the wedge-shaped surface and the steel column beam.

[0104] Furthermore, a toe plate 31 is welded to the inclined surface of the shear key 3. The toe plate 31 is also the attachment body of the inclined surface 311. The toe plate is perpendicular to the shear key 3, which increases the contact area between the shear key and the wedge-shaped surface. This design can also effectively prevent the shear key from crushing the slots between the pier column and maintain the installation stability of the shear key.

[0105] Compared with traditional concrete column-supported beams, the present invention has superior local bearing capacity, wedge-shaped self-locking performance, structural stability, and reliable connection in the above specific embodiments.

[0106] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements to the present invention by those skilled in the art should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for constructing bridge jacking steel column-mounted beams, characterized in that, Follow these steps in sequence: Step 1: Cut concrete around the pier column to form a groove. The groove consists of horizontal and vertical sections. Stirrup grooves are cut between adjacent grooves. Step 2: The shear key is placed vertically in the vertical part of the slot. The shear key is a rectangular thick steel plate with reserved holes for reinforcing bars to pass through and bolt holes for mating with the steel column beam. The reinforcing bars passing through the shear key are placed in the horizontal part of the slot and spot welded to the original reinforcing bars of the pier. The stirrup slot is used for the arrangement of stirrups, and the stirrups are set along the circumference of the pier and welded to the reinforcing bars in the shear key. The stirrups connect multiple shear keys located in different positions to form a ring-shaped reinforcing cage. Step 3: Pour high-strength concrete into the groove, smooth the outer surface, and cure until hardened; Step 4: Secure the bolt holes on the shear keys to the steel column beam one by one using high-strength bolts and nuts; Step 5: Connect the ends of adjacent steel column beams around the pier. Step six: Place the lifting jacks between the steel column beam and the bridge to lift the bridge and extend the piers. After the bridge is lifted into place and the piers are extended, dismantle the steel column beam in reverse order of steps four and five, following the principle of installation before dismantling.

2. The construction method for bridge jacking steel column beams according to claim 1, characterized in that, The end of the shear key near the pier is an inclined surface. A toe plate is welded to the inclined surface of the shear key. The vertical surface where the slot is located is a wedge-shaped surface with an inclination from top to bottom and from inside to outside. The toe plate and the wedge-shaped surface are wedge-shaped.

3. A method for constructing bridge jacking steel column-mounted beams, characterized in that, Follow these steps in sequence: Step 1: Cut concrete around the pier column to form a groove. The groove consists of horizontal and vertical sections. Stirrup grooves are cut between adjacent grooves. Step 2: Fix the embedded part in the slot of the pier column. The embedded part is an open box-shaped structure composed of two side plates, three horizontal plates and one back plate, with an inner cavity. One horizontal plate is provided with a groove, which is located near the back plate. A locking post is provided in the inner cavity. The steel bars passing through the embedded part are placed in the horizontal part of the slot and spot welded to the original steel bars of the pier column. The stirrup slot is used for the arrangement of stirrups, and the stirrups are set along the circumference of the pier column and welded to the steel bars in the shear keys. The stirrups connect multiple shear keys located in different directions to form a ring-shaped steel cage. High-strength concrete is poured into the slot, the outer surface is smoothed, and cured until hardened. Step 3: Install the shear key. The shear key is a rectangular steel plate with at least a number of L-shaped grooves and a protrusion. Push the upper edge of the shear key horizontally along the upper edge of the inner cavity of the embedded part, and move it from top to bottom after it is inserted to the bottom. During the movement from top to bottom, the protrusion is embedded in the groove, and the locking pin is embedded in the groove at the same time. Then, insert a wedge into the upper cavity of the shear key. Step 4: Secure the bolt holes on the shear keys to the steel column beam one by one using high-strength bolts and nuts; Step 5: Connect the ends of adjacent steel column beams around the pier. Step six: Place the lifting jacks between the steel column beam and the bridge to lift the bridge and extend the piers. After the bridge is lifted into place and the piers are extended, dismantle the steel column beam in reverse order of steps three, four and five, following the principle of installation before dismantling. Finally, remove the shear keys.

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