External prestressing steel structure anchoring block for reinforcing bridge hogging moment area and construction method

Abstract

The invention relates to the field of pre-stress reinforcement, in particular to an external pre-stress steel structure anchoring block for bridge hogging moment area reinforcement and a construction method.The external pre-stress steel structure anchoring block comprises a combination of a steel base plate, an anchoring block body, a thermal shrinkage sleeve and a rear anchoring part, the steel base plate can be stably connected with a bridge, and then the anchoring block body is installed on the steel base plate; a protection pipe is further integrally formed on the anchoring block body, the prestress finished cable can penetrate through the protection pipe, the prestress finished cable can be effectively protected, meanwhile, a sealing device is further arranged, the sealing device can further protect the prestress finished cable, and the sealing effect is good. The anchoring block is high in overall strength and reasonable in structure, the number of the plates can be adjusted according to the anchoring force, a prestressed finished cable can be installed more conveniently in site construction, meanwhile, detailed S1, S2, S3, S4 and S5 construction guidance steps are further provided, and the construction efficiency is improved. The external prestressing reinforcing anchoring block can ensure the stability of a bridge under the condition of being convenient to install.

Description

Technical Field

[0001] The present application relates to the field of prestressed reinforcement, and in particular to an external prestressed steel structure anchor block and a construction method for reinforcing a negative bending moment zone of a bridge. Background Art

[0002] With the rapid development of my country's economy in recent decades, a large number of conventional beam bridges built in my country on cross-river and cross-river channels mostly use large-span beams. With the rapid development of the economy, the traffic volume and load have increased rapidly. Such large-span beam bridges generally have problems such as mid-span structural cracking, reduced stiffness, and reduced durability, and are in urgent need of reinforcement and reconstruction. During the operation of the bridge, due to prestress loss, concrete creep and other reasons, the long-term deflection has a tendency to increase year by year. Excessive deflection and concrete cracking of the bridge not only affect the smooth traffic capacity of the bridge, but may also cause steel corrosion, reducing the bearing capacity and durability of the bridge. For bridges with excessive deflection, corresponding reinforcement measures should be taken to improve the overall performance of the bridge. Common reinforcement methods for this type of disease include increasing the cross-section method, bonding steel plate reinforcement method, and external prestress reinforcement method.

[0003] External prestressing reinforcement technology is a method used to enhance the bearing capacity of structural members and improve their performance, especially in bridge engineering. In the external prestressing system, the prestressed steel cables or steel bars are arranged on the outside of the structure, rather than embedded in the concrete as in traditional prestressed concrete. The benefits of this include convenient inspection, maintenance and replacement of prestressed tendons. The steel structure anchor block is a key component in the external prestressing system. Their main function is to anchor the prestressed tendons (steel cables or steel bars) and effectively transfer the force of the prestressed tendons to the main structure. The reinforced area is the upper part of the bridge span. The optional method is to groove the bridge deck and apply prestressed tendons, but this requires the overall renovation of the bridge deck, which not only has a long construction period and poor economic efficiency, but also requires the bridge to be closed and stopped from operating, affecting urban traffic.

[0004] It can be seen from the above-mentioned related technologies that prestressed anchor blocks are crucial in the external prestressed anchor structure. At present, the external prestressed reinforcement anchor blocks mainly adopt ordinary reinforced concrete anchor blocks and ordinary steel structure anchor blocks. Ordinary reinforced concrete anchor blocks are connected to the beam body through embedded bars to form an anchoring system. This type of anchor block generally has problems such as large size, complex construction, long construction period, and increased structural dead load during implementation. In addition, local fracturing and cracking of the interface between new and old concrete are prone to occur during the tensioning process. Ordinary steel structure anchor blocks are made of ordinary low-alloy steel materials and are anchored to the beam body through rear anchors. Although such anchor blocks can be prefabricated, assembled, and factory-produced, the later maintenance costs of ordinary steel are high. Therefore, how to make the external prestressed reinforcement anchor blocks in the related technology easy to install and ensure the stability of the bridge has become an urgent problem to be solved. Summary of the Invention

[0005] In order to enable the external prestressed reinforcement anchorage block in the related art to ensure the stability of the bridge while being easy to install, the present application provides an external prestressed steel structure anchorage block for strengthening the negative moment area of the bridge and a construction method therefor.

[0006] In a first aspect, an external prestressed steel structure anchorage block for strengthening the negative moment area of the bridge provided by the present application adopts the following technical solutions: An external prestressed steel structure anchorage block for strengthening the negative moment area of the bridge, comprising: A steel backing plate, fixedly connected to the bridge through a post-anchor; An anchorage block body, including an anchorage support and an anchorage protection cover. The anchorage support is fixedly connected to the steel backing plate. The anchorage support is used to fix the steel strands of the prestressed finished cable. The anchorage protection cover is detachably connected to the anchorage support; A protection tube, arranged on the anchorage support and integrally formed with the anchorage support. The protection tube can accommodate the prestressed finished cable; A heat shrinkable sleeve, arranged at one end of the protection tube away from the anchorage protection cover; Wherein, the anchorage protection cover, the protection tube and the heat shrinkable sleeve can isolate the end of the prestressed finished cable from the external environment.

[0007] By adopting the above technical solutions, the anchorage block of the present application is set as a combination of a steel backing plate, an anchorage block body, a protection tube and a heat shrinkable sleeve. First, the steel backing plate is fixed on the bridge through a post-anchor to provide a stable connection between the anchorage block and the bridge, and bear and disperse the acting force of the prestress. Secondly, setting the anchorage block body as a combination of an anchorage support and a protection cover makes the anchorage block have higher strength and durability, and at the same time protects the prestressed finished cable from the external environment. At the same time, the integrally formed design of the protection tube improves the structural stability and facilitates the smooth passing of the prestressed finished cable. Finally, the heat shrinkable sleeve can effectively isolate the end of the prestressed finished cable from the outside world, playing a role in sealing, anti-corrosion and extending the service life. To a certain extent, the present application can enable the external prestressed reinforcement anchorage block in the related art to ensure the stability of the bridge while being easy to install. By adopting the external prestressed method of the present application, the bridge span can be strengthened without affecting the traffic on the upper part of the bridge.

[0008] Optionally, an anchor plate and clamping pieces are arranged on the anchorage support. A perforation is formed on the anchor plate. The steel strands of the prestressed finished cable can pass through the perforation, and the clamping pieces can clamp the steel strands of the prestressed finished cable.

[0009] By adopting the above technical solution, perforations are provided on the anchor plate, and the steel strands pass through and are clamped by the wedge grips, which can effectively provide a more stable anchoring method, ensure the stability of the prestressed finished cable, and the design of the anchor plate and the wedge grips increases the anti-slip ability of the steel strands and optimizes the overall mechanical properties.

[0010] Optionally, a plurality of wedge grips are provided, a plurality of perforations are provided, the plurality of wedge grips correspond to the plurality of perforations one by one, and one perforation corresponds to the steel strands of one prestressed finished cable.

[0011] By adopting the above technical solution, the corresponding arrangement of the plurality of wedge grips and the plurality of perforations can make each steel strand correspond to one wedge grip to ensure uniform stress on each steel strand.

[0012] Optionally, locking blocks are provided on the inner wall of the perforation, locking grooves are provided on the wedge grips, and the locking blocks can be inserted into the locking grooves.

[0013] By adopting the above technical solution, the arrangement of the locking blocks and the locking grooves enhances the stability of the steel strands, and the cooperation of the locking blocks and the locking grooves effectively improves the installation accuracy and reliability.

[0014] Optionally, a loosening prevention device is further provided at one end of the wedge grip away from the anchor plate. The loosening prevention device includes a loosening prevention splint group and a loosening prevention adjusting sleeve. The loosening prevention splint group is fixedly connected to the anchoring support, the loosening prevention splint group and the loosening prevention adjusting sleeve are threadedly connected, and the end of the loosening prevention adjusting sleeve abuts against the end of the wedge grip.

[0015] By adopting the above technical solution, the arrangement of the loosening prevention device can effectively prevent the wedge grips from falling off due to stress or vibration, and the loosening prevention adjusting sleeve can flexibly adjust the clamping force to adapt to different prestress requirements.

[0016] Optionally, an anti-corrosion grease is applied to the outer surface of the anchoring protective cover.

[0017] By adopting the above technical solution, the anti-corrosion grease provides additional anti-corrosion protection, extends the service life of the anchoring block in a harsh environment, thus effectively reducing the maintenance requirements and lowering the later operation cost.

[0018] Optionally, a sealing device is further provided between the heat shrinkable sleeve and the protective tube.

[0019] By adopting the above technical solution, the arrangement of the sealing device strengthens the sealing performance of the interface, prevents moisture, dust and other pollutants from entering the prestressed system, thereby improving the overall durability and reliability of the structure of the present application and extending the service life.

[0020] Optionally, a reinforcing plate group is also welded on the anchoring support. The reinforcing plate group includes a reinforcing horizontal plate and a reinforcing vertical plate. The reinforcing horizontal plate extends in the horizontal direction, and the size of the reinforcing horizontal plate gradually decreases from the end of the prestressed finished cable towards the center. The reinforcing vertical plate extends in the vertical direction, and the size of the reinforcing vertical plate gradually increases from top to bottom.

[0021] By adopting the above technical solution, the horizontal plate, vertical plate and rib plate form a firm connection among multiple reinforcing plates, effectively enhancing the bearing capacity of the anchoring block of the present application, preventing deformation or damage caused by stress concentration, and the multi-directional support design improves the overall anti-shear, anti-torsion and anti-bending capabilities of the structure.

[0022] In a second aspect, the present application also provides a construction method for the construction and installation of an external prestressed steel structure anchoring block for strengthening the negative moment area of a bridge, including the following steps: S1. Fix the steel backing plate on the bridge using the rear anchor; S2. Install the anchoring support on the steel backing plate using the rear anchor, and at the same time weld the protection pipe on the anchoring support; S3. Pass the prestressed finished cable through the protection pipe and anchor the steel strands of the prestressed finished cable on the anchoring support; S4. Install the heat shrinkable sleeve at the junction of the prestressed finished cable and the protection pipe; S5. Install the other end of the prestressed finished cable on the adjacent anchoring support.

[0023] By adopting the above technical solution, guiding the construction according to S1→S2→S3→S4→S5 provides a systematic construction process, which can effectively ensure the installation efficiency and construction quality. At the same time, it also clarifies the installation steps of the anchoring block of the present application, facilitating the quick understanding and operation of construction personnel. To a certain extent, the present application can enable the external prestressed reinforcement anchoring block in the related technology to ensure the stability of the bridge while being easy to install.

[0024] Optionally, after S3 is completed, it further includes welding a reinforcing plate group on the anchoring support. The reinforcing plate group includes a reinforcing horizontal plate and a reinforcing vertical plate. The reinforcing horizontal plate extends in the horizontal direction, and the size of the reinforcing horizontal plate gradually decreases from the end of the prestressed finished cable towards the center. The reinforcing vertical plate extends in the vertical direction, and the size of the reinforcing vertical plate gradually increases from top to bottom.

[0025] By adopting the above technical solution, in the construction method, the welding stage of the reinforcing plate group is further emphasized, effectively improving the structure of the anchoring block, meeting higher prestress requirements, and at the same time, the welding of the reinforcing plate group can further enhance the overall safety and durability of the anchoring block.

[0026] In summary, the present application includes at least one of the following beneficial technical effects: 1. Wide scope of application: The external prestressed reinforcement method is divided into the external prestressed carbon cloth reinforcement method, the external prestressed steel bundle reinforcement method, etc. Among them, the external prestressed steel bundle reinforcement method is suitable for projects that can improve the structural bearing capacity to a greater extent. The anchor block not only serves as an operating platform for the steel bundle to play a role and implement tensioning, but also serves as the basis for the steel bundle to maintain stress and be firmly fixed. It is a key implementation node for external prestressed steel bundle reinforcement, and its optimized design plays a vital role. The steel structure anchor block is simple to construct and operate, occupies a small space, causes little damage to the original structure, and can be applied to other projects by simply and flexibly adjusting the number of steel bundles required according to actual needs; 2. Reduce construction period, reduce impact on bridge deck traffic, and have good social benefits: The reinforced area is the upper part of the bridge span. The optional method is to groove the bridge deck and apply prestressed tendons, but this requires the overall renovation of the bridge deck, which not only has a long construction period and poor economic efficiency, but also requires the closure of the bridge and suspension of operation, affecting urban traffic. This application can, to a certain extent, enable the external prestressed reinforcement anchor blocks in the relevant technology to ensure the stability of the bridge while being easy to install. By using the external prestressing method of this application, the bridge span can be reinforced without affecting the traffic on the upper part of the bridge; 3. Simple structure and clear force; 4. By configuring the anchor block of the present application as a combination of a steel pad, an anchor block body, a protective tube, and a heat shrink sleeve, firstly, the steel pad is fixed to the bridge through the heat shrink sleeve, providing a stable connection between the anchor block and the bridge, and bearing and dispersing the prestressed force; secondly, configuring the anchor block body as a combination of an anchor support and a protective cover makes the anchor block have higher strength and durability, while protecting the prestressed finished cable from the external environment; at the same time, the one-piece design of the protective tube improves the stability of the structure and facilitates the smooth installation of the prestressed finished cable; finally, the heat shrink sleeve can effectively protect the end of the prestressed finished cable from the outside world, and play a role in sealing, anti-corrosion and extending the service life; 5. By arranging the reinforcing plate group into a combination of transverse plates, longitudinal plates and rib plates, a solid connection is formed between the transverse plates, longitudinal plates and rib plates, and multiple reinforcing plates, which effectively enhances the bearing capacity of the anchor block of the present application and prevents deformation or damage caused by stress concentration. The multi-directional support design improves the overall shear, torsion and bending resistance of the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of an embodiment of the present application in which an external prestressed steel structure anchor block used for strengthening the negative bending moment zone of a bridge is installed on a bridge (showing the situation in which two steel structure anchor blocks pull the prestressed finished cables).

[0028] Figure 2 It is a detailed drawing of an external prestressed steel structure anchor block used for reinforcing the negative bending moment zone of a bridge according to an embodiment of the present application.

[0029] Figure 3 It is a side sectional view of the connection between the external prestressed steel structure anchorage block for strengthening the negative moment area of the bridge and the bridge in the embodiment of the present application.

[0030] Figure 4 It is Figure 2 the enlarged view at position A in

[0031] Figure 5 It is Figure 1 the enlarged view at position B in

[0032] Figure 6 It is a schematic diagram of the model for the finite element numerical simulation of the anchorage block body in the embodiment of the present application.

[0033] Figure 7 It is Figure 6 the deformation nephogram of

[0034] Figure 8 It is Figure 6 the stress nephogram of

[0035] Explanation of reference numerals: 1. Steel backing plate; 2. Bridge; 3. Anchorage block body; 31. Anchorage support; 32. Anchorage protection cover; 4. Protection pipe; 5. Prestressed finished cable; 51. Steel strand; 6. Heat shrinkable sleeve; 7. Anchor plate; 8. Wedge; 9. Perforation; 10. Locking block; 11. Locking groove; 12. Anti-loosening device; 121. Anti-loosening splint group; 122. Anti-loosening adjusting sleeve; 13. Sealing device; 14. Reinforcement plate group; 141. Reinforcement cross plate; 142. Reinforcement vertical plate; 15. High-strength grouting material. Detailed implementation manners

[0036] The following further elaborates on the present application in conjunction with the attached Figure 1-8 drawings.

[0037] The embodiment of the present application discloses an external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge and a construction method.

[0038] It should be noted that in the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention 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 should not be construed as a limitation to the present invention.

[0039] In a first aspect, the present application provides an external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge.

[0040] Referring to Figure 1 and Figure 2 , an external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge includes a combination of a steel backing plate 1, an anchorage block body 3, a protection tube 4, and a heat shrinkable sleeve 6. Among them, the steel backing plate 1 can be stably connected to the bridge 2, and then the anchorage block body 3 is installed on the steel backing plate 1. A protection tube 4 is integrally formed on the anchorage block body 3. The protection tube 4 can allow the prestressed finished cable 5 to pass through, which can effectively protect the prestressed finished cable 5. At the same time, a heat shrinkable sleeve 6 is also provided, and the heat shrinkable sleeve 6 can further protect the prestressed finished cable 5. The anchorage block provided by the present application has high overall strength and a reasonable structure, and is more convenient for installing the prestressed finished cable 5. Thus, to a certain extent, it can ensure the stability of the bridge 2 while facilitating the installation of the external prestressed reinforcement anchorage block in the related art. By adopting the external prestressed method of the present application, the bridge span can be strengthened without affecting the upper traffic of the bridge 2.

[0041] Specifically, in the embodiment of the present application, the steel backing plate 1 is fixedly connected to the bridge 2 through post-anchoring members.

[0042] It should be noted that in the embodiment of the present application, the steel backing plate 1 is fixedly connected to the bridge 2 through multiple post-anchoring members. Referring to Figure 3 , at the same time, high-strength grouting material 15 is filled in the gap between the steel backing plate 1 and the bridge 2, which can effectively enhance the connection strength and effectively protect the post-anchoring members, improving the stability.

[0043] Specifically, in the embodiment of the present application, the anchorage block body 3 includes an anchorage support 31 and an anchorage protection cover 32. The anchorage support 31 is fixedly connected to the steel backing plate 1, and the anchorage protection cover 32 is detachably connected to the anchorage support 31. That is to say, the anchorage support 31 is connected to the steel backing plate 1 through post-anchoring members, welding, or other mechanical connection methods, or can be integrally formed with the steel backing plate 1.

[0044] For the anchorage protection cover 32, it is to protect the steel strands 51 of the prestressed finished cable 5 anchored on the anchorage support 31, and can effectively prevent the steel strands 51 from being corroded, resulting in the failure of the entire structure.

[0045] Furthermore, referring to Figure 2 and Figure 4, an anchor plate 7 and a wedge 8 are provided on the anchoring bearing 31. A through hole 9 is formed on the anchor plate 7. The steel strand 51 of the finished prestressed cable 5 can pass through the through hole 9, and the wedge 8 can clamp the steel strand 51 of the finished prestressed cable 5. This method can effectively provide a more stable anchoring method to ensure the stability of the finished prestressed cable 5. The design of the anchor plate 7 and the wedge 8 increases the anti-slip ability of the steel strand 51 and optimizes the overall mechanical properties.

[0046] Furthermore, a plurality of wedges 8 are provided, and a plurality of through holes 9 are formed. The plurality of wedges 8 correspond to the plurality of through holes 9 one by one, and one through hole 9 corresponds to the steel strand 51 of one finished prestressed cable 5.

[0047] The corresponding arrangement of the plurality of wedges 8 and the plurality of through holes 9 can make each steel strand 51 correspond to a plurality of wedges 8 to ensure uniform stress of each steel strand 51. At the same time, when one steel strand 51 breaks away from the through hole 9, it can ensure that other steel strands 51 can work normally and have sufficient safety redundancy.

[0048] At the same time, in order to ensure the stability of the anchoring of the steel strand 51, in the embodiment of the present application, a locking block 10 is provided on the hole wall of the through hole 9, and a locking groove 11 is formed on the wedge 8. The locking block 10 can be inserted into the locking groove 11. It should be noted that, as can be seen from the accompanying drawings, the wedge 8 should be set in a uniform variable cross-section form so that the locking block 10 can be effectively inserted into the locking groove 11. In other embodiments, the wedge 8 can also be set in an equal cross-section form, but the locking block 10 needs to be improved, and the locking block 10 can be set in an elastic structure, which is also an embodiment that can be implemented in the present application.

[0049] The arrangement of the locking block 10 and the locking groove 11 enhances the stability of the steel strand 51, and the cooperation of the locking block 10 and the locking groove 11 effectively improves the installation accuracy and reliability.

[0050] Furthermore, in order to further improve the stability of the anchoring of the steel strand 51, a loosening prevention device 12 is also provided at the end of the wedge 8 away from the anchor plate 7. The loosening prevention device 12 includes a loosening prevention clamping plate group 121 and a loosening prevention adjusting sleeve 122. The loosening prevention clamping plate group 121 is fixedly connected to the anchoring bearing 31. The loosening prevention clamping plate group 121 and the loosening prevention adjusting sleeve 122 are threadedly connected. The end of the loosening prevention adjusting sleeve 122 abuts against the end of the wedge 8, and the loosening prevention clamping plate group 121 can clamp the steel strand 51 of the finished prestressed cable 5.

[0051] The arrangement of the loosening prevention device 12 can effectively prevent the wedge 8 from falling off due to force or vibration. Moreover, the loosening prevention adjusting sleeve 122 can flexibly adjust the clamping force to adapt to different prestress requirements, and can provide greater safety redundancy for the anchoring of the steel strand 51 in the present application.

[0052] Meanwhile, regarding the anchoring protective cover 32, an anti-corrosion grease is applied to the outer surface of the anchoring protective cover 32. In the embodiment of the present application, the anti-corrosion grease can be made of a mixture of tung oil and copper tung oil acid, epoxy-phenolic paint, epoxy resin paint and other materials.

[0053] Anti-corrosion grease provides additional anti-corrosion protection, extending the service life of the anchor block in harsh environments, thereby effectively reducing maintenance requirements and lowering subsequent operating costs.

[0054] Specifically, the protection tube 4 is arranged on the anchor support 31 and is integrally formed with the anchor support 31, and the prestressed finished cable 5 can be passed through the protection tube 4. The heat shrink sleeve 6 is arranged at one end of the protection tube 4 away from the anchor protection cover 32. The protection tube 4 and the heat shrink sleeve 6 are arranged to further protect the prestressed finished cable 5 and reduce the possibility of damage to the steel strand 51 of the prestressed finished cable 5.

[0055] Furthermore, a sealing device 13 is provided between the heat shrink sleeve 6 and the protection tube 4 .

[0056] The provision of the sealing device 13 enhances the sealing performance of the interface and prevents moisture, dust and other pollutants from entering the prestressed system, thereby improving the overall durability and reliability of the structure of the present application and extending its service life.

[0057] Regarding the sealing device 13 , in the embodiment of the present application, the sealing device 13 is made of a combination of five special-shaped blocks, which can effectively ensure a dry environment at the anchoring location of the present application and effectively improve the service life of the steel strand 51 .

[0058] Reference Figure 5 and Figure 6 Furthermore, a reinforcing plate group 14 is welded on the anchor support 31, and the reinforcing plate group 14 includes a reinforcing transverse plate 141 and a reinforcing vertical plate 142. The reinforcing transverse plate 141 extends in the horizontal direction, and the size of the reinforcing transverse plate 141 gradually decreases from the end of the prestressed finished cable 5 to the center, and the reinforcing vertical plate 142 extends in the vertical direction, and the size of the reinforcing vertical plate 142 gradually increases from high to low.

[0059] Among them, a plurality of reinforcing transverse plates 141 are evenly spaced in the vertical direction, and a plurality of reinforcing vertical plates 142 are evenly spaced in the horizontal direction. The plurality of reinforcing transverse plates 141 and the plurality of reinforcing vertical plates 142 are welded to the steel base plate 1 .

[0060] A stable connection is formed between the reinforced horizontal plate 141 and the reinforced vertical plate 142, which effectively enhances the bearing capacity of the anchor block of the present application and prevents deformation or damage caused by stress concentration. The multi-directional support design improves the overall shear, torsion and bending resistance of the structure.

[0061] The implementation principle of an external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge in an embodiment of the present application is as follows: The anchorage block of the present application is set as a combination of a steel backing plate 1, an anchorage block body 3, a protection tube 4, and a heat shrinkable sleeve 6. First, the steel backing plate 1 is fixed on the bridge 2 through post-anchoring members, providing a stable connection between the anchorage block and the bridge 2 and bearing and dispersing the acting force of prestress. Secondly, the anchorage block body 3 is set as a combination of an anchorage support 31 and a protective cover 32, making the anchorage block have higher strength and durability, and at the same time protecting the prestressed finished cable 5 from the external environment. At the same time, the integrally formed design of the protection tube 4 improves the structural stability and facilitates the smooth threading of the prestressed finished cable 5. Finally, the heat shrinkable sleeve 6 can effectively isolate the end of the prestressed finished cable 5 from the outside world, playing a role in sealing, anti-corrosion, and extending the service life. To a certain extent, the present application enables the external prestressed reinforcement anchorage block in the related art to ensure the stability of the bridge 2 while being easy to install.

[0062] Second, referring to Figure 1-5 , the present application also provides a construction method applicable to the external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge in the present application, including the following steps: S1. Fix the steel backing plate 1 on the bridge 2 using post-anchoring members.

[0063] In S1, when fixing the steel backing plate 1 on the bridge 2, it is necessary to first, according to the design requirements, integrally form or weld each component of the steel backing plate 1 according to the anchorage block of the present application in the factory. And during the installation process, the following steps should be strictly followed: a. Use a steel bar detector to detect the position of the main beam distribution steel bars and lay out the lines on the main beam; b. Drill holes according to the anchorage block component drawing and the anchor bolt layout drawing. If there is interference with the prestressed steel bundle and ordinary steel bars, appropriate displacement can be made; c. After the hole positions are appropriate, use a plastic board or wooden board to lay out the drilling positions of the steel plate and correspond them to the steel component to drill holes; d. Drive anchor bolts into the holes and remove the nuts; e. Try to lay out the steel plate. If it can be effectively connected to the anchor bolts, directly install the nuts. At this time, pre-tighten but do not tighten the nuts; f. If there are slight deviations in the hole positions of the steel plate, remove the steel plate, ream the holes according to the positional relationship between the drilling of the steel plate and the deviation of the post-anchoring members, and weld the steel plate and the shear sleeve according to the direction of reaming; g. Install the nuts. At this time, pre-tighten but do not tighten the nuts; h. The installation process of the anchor bolts is detailed in the product technical manual and the anchor bolt construction requirements.

[0064] S2. Install the anchorage support 31 on the steel backing plate 1 using post-anchoring members, and at the same time weld the protection tube 4 to the anchorage support 31.

[0065] In S2, after installing the anchorage support 31 on the steel backing plate 1, it is necessary to pour an adhesive between the anchorage support 31 and the steel backing plate 1, which can effectively ensure the stability of the anchorage support 31.

[0066] S3. Pass the finished prestressed cable 5 through the protection pipe 4 and anchor the steel strands 51 of the finished prestressed cable 5 on the anchor support 31.

[0067] After S3 is completed, it also includes welding a reinforcing plate group 14 on the anchor support 31. The reinforcing plate group 14 includes a reinforcing horizontal plate 141, a reinforcing vertical plate 142, and a reinforcing rib plate 143. There are multiple pieces of the reinforcing horizontal plate 141, the reinforcing vertical plate 142, and the reinforcing rib plate 143. Multiple pieces of the reinforcing horizontal plate 141 and multiple pieces of the reinforcing vertical plate 142 are both welded to the steel backing plate 1, and multiple pieces of the reinforcing rib plate 143 are welded between adjacent reinforcing vertical plates 142.

[0068] In the construction method, the welding stage of the reinforcing plate group 14 is further emphasized, effectively improving the structure of the anchor block, meeting higher prestress requirements. At the same time, the welding of the reinforcing plate group 14 can further enhance the overall safety and durability of the anchor block.

[0069] S4. Install the heat shrinkable sleeve 6 at the junction of the finished prestressed cable 5 and the protection pipe 4.

[0070] S5. Install the other end of the finished prestressed cable 5 on the adjacent anchor support 31.

[0071] Guided by S1→S2→S3→S4→S5 for construction, it provides a systematic construction process, which can effectively ensure the installation efficiency and construction quality. At the same time, it also clarifies the installation steps of the anchor block in this application, facilitating the quick understanding and operation of construction personnel. To a certain extent, this application can enable the external prestressed reinforcement anchor block in the related technology to ensure the stability of the bridge 2 while being easy to install. By adopting the external prestressed method of this application, the bridge span can be reinforced without affecting the upper transportation of the bridge 2.

[0072] Further referring to Figure 6-8 , in order to verify the effect of the anchor block body 3 in the embodiment of this application, the applicant of this application conducted a finite element numerical simulation. The following effects can be obtained from the numerical simulation combined with engineering practice: 1. Large applicable range: The external prestressed reinforcement method is divided into the external prestressed carbon cloth reinforcement method, the external prestressed steel strand reinforcement method, etc. Among them, the external prestressed steel strand reinforcement method is applicable to projects with a greater degree of improving the structural bearing capacity. The anchor block not only serves as an operating platform for the steel strand to exert its function and perform tensioning operations, but also is the basis for the steel strand to maintain stress and be firmly fixed. It is a key implementation node for external prestressed steel strand reinforcement, and its optimized design plays a crucial role. This steel structure anchor block is simple in construction operation, small in occupied space, small in damage to the original structure, and can be simply and flexibly adjusted according to the number of steel strands required in actual situations, and can be applied to other projects; 2. Reduce the construction period, reduce the impact on bridge deck traffic, and have good social benefits: The reinforced area is the upper part of the bridge span. An optional method is to slot the bridge deck to apply prestressed tendons, but this requires a complete renovation of the bridge deck, which not only has a long construction period, poor economy, but also requires the bridge to be closed and out of service, affecting urban traffic. To a certain extent, this application enables the external prestressed reinforcement anchorage block in the related technology to ensure the stability of the bridge while being easy to install. By using the external prestressed method of this application, the bridge span can be reinforced without affecting the transportation on the upper part of the bridge; 3. Simple structure and clear force transmission.

[0073] The above are all the preferred embodiments of this application, and the protection scope of this application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape, and principle of this application shall be covered by the protection scope of this application.

Claims

1. An external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge, characterized in that, Comprising: Steel backing plate (1), fixedly connected to the bridge (2) through post-anchoring members; Anchoring block body (3), including an anchoring support (31) and an anchoring protective cover (32). The anchoring support (31) is fixedly connected to the steel backing plate (1). The anchoring support (31) is used to fix the steel strand (51) of the finished prestressed cable (5). The anchoring protective cover (32) is detachably connected to the anchoring support (31); Protection tube (4), arranged in the middle of the anchoring support (31) and integrally formed with the anchoring support (31). The protection tube (4) can accommodate the finished prestressed cable (5) to pass through; Heat shrinkable sleeve (6), arranged at one end of the protection tube (4) away from the anchoring protective cover (32); Wherein, the anchoring protective cover (32), the protection tube (4) and the heat shrinkable sleeve (6) can isolate the end of the finished prestressed cable (5) from the external environment.

2. The external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge according to claim 1, wherein An anchor plate (7) and wedge grips (8) are arranged on the anchoring support (31). A through hole (9) is formed on the anchor plate (7). The steel strand (51) of the finished prestressed cable (5) can pass through the through hole (9), and the wedge grips (8) can clamp the steel strand (51) of the finished prestressed cable (5).

3. The external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge according to claim 2, characterized in that, A plurality of wedge grips (8) are provided. A plurality of through holes (9) are formed. The plurality of wedge grips (8) correspond to the plurality of through holes (9) one by one, and one through hole (9) corresponds to the steel strand (51) of one finished prestressed cable (5).

4. The external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge according to claim 2, wherein Locking blocks (10) are arranged on the inner wall of the through hole (9). Locking grooves (11) are formed on the wedge grips (8). The locking blocks (10) can be inserted into the locking grooves (11).

5. The external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge according to claim 2, characterized in that, An anti-loosening device (12) is further arranged at one end of the wedge grip (8) away from the anchor plate (7). The anti-loosening device (12) includes an anti-loosening clamping plate group (121) and an anti-loosening adjusting sleeve (122). The anti-loosening clamping plate group (121) is fixedly connected to the anchoring support (31). The anti-loosening clamping plate group (121) and the anti-loosening adjusting sleeve (122) are threadedly connected. The end of the anti-loosening adjusting sleeve (122) abuts against the end of the wedge grip (8).

6. The external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge according to claim 1, characterized in that, Anticorrosive grease is smeared on the outer surface of the anchoring protective cover (32).

7. The external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge according to claim 1, wherein A sealing device (13) is further arranged between the heat shrinkable sleeve (6) and the protection tube (4).

8. The external prestressed steel structure anchorage block for strengthening the negative moment area of a bridge according to claim 1, wherein Reinforcing plate groups (14) are also welded on the anchoring support (31). The reinforcing plate groups (14) include reinforcing horizontal plates (141) and reinforcing vertical plates (142). The reinforcing horizontal plates (141) extend in the horizontal direction, and the size of the reinforcing horizontal plates (141) gradually decreases from the end of the finished prestressed cable (5) towards the center. The reinforcing vertical plates (142) extend in the vertical direction, and the size of the reinforcing vertical plates (142) gradually increases from high to low.

9. A construction method, applicable to the external prestressed steel structure anchoring block for strengthening the negative moment area of a bridge according to any one of claims 1-7, comprising the following steps: S1. Use post-anchoring members to fix the steel backing plate (1) on the bridge (2); S2. After use, install the anchoring support (31) on the steel backing plate (1) with post-anchoring parts, and at the same time weld the protection pipe (4) to the anchoring support (31); S3. Pass the finished prestressed cable (5) through the protection pipe (4) and anchor the steel strands (51) of the finished prestressed cable (5) to the anchoring support (31); S4. Install the heat shrinkable sleeve (6) at the junction of the finished prestressed cable (5) and the protection pipe (4); S5. Install the other end of the finished prestressed cable (5) on the adjacent anchoring support (31).

10. The construction method according to claim 9, characterized in that, After the step S3 is completed, it further includes that a reinforcing plate group (14) is also welded on the anchoring support (31). The reinforcing plate group (14) includes a reinforcing horizontal plate (141) and a reinforcing vertical plate (142). The reinforcing horizontal plate (141) extends in the horizontal direction, and the size of the reinforcing horizontal plate (141) gradually decreases from the end of the finished prestressed cable (5) towards the center. The reinforcing vertical plate (142) extends in the vertical direction, and the size of the reinforcing vertical plate (142) gradually increases from high to low.

Images