A reinforcement system and reinforcement method for converting a T-beam into a box beam by gluing a steel plate

Abstract

The present invention discloses a reinforcement system and a reinforcement method for converting a box beam by pasting a steel plate on a T beam, wherein the reinforcement system comprises a reinforcement steel plate pasted on the bottom of the web of the T beam; a pressurized fixing unit arranged at intervals at the bottom of the web of the T beam, the pressurized fixing unit comprising an angle steel and a pressurized steel plate; a connecting steel plate for connecting adjacent T beams; the reinforcement steel plate pasted on the bottom of the web of the T beam; the angle steel is fixed on both sides of the lower part of the web of the T beam; the pressurized steel plate is fixed on the lower part of the reinforcement steel plate; the connecting steel plate is clamped on the pressurized fixing unit at the bottom of the web of the adjacent T beam; and the T-shaped section is closed into a box-shaped section with better overall stress performance through the reinforcement system. The present invention has a simple structure and is convenient for construction. It can not only restore and improve the bending stiffness and bearing capacity of the main beam, but also improve and enhance the overall stress performance of the bridge.

Description

Technical Field

[0001] The invention relates to the technical field of bridge reinforcement, and in particular to a reinforcement system and a reinforcement method for converting a T-beam into a box beam by bonding a steel plate. Background Art

[0002] Among the medium and small span concrete bridges in my country, T-section concrete simply supported beam bridges account for a considerable proportion. As early as the 1950s and 1960s, many concrete simply supported T beam bridges were built in my country because of their simple structure, clear force, and easy erection and installation. With the rapid development of the economy and society, the traffic volume has increased dramatically, and the overload rate has also tended to increase. This change has brought two major structural safety problems to the early designed and constructed concrete simply supported T beam bridges: 1) Due to the low design load standards in the early days and the increasing number of heavy-loaded vehicles, a large number of such bridges have insufficient bearing capacity; 2) With the increase in the operating years and the increase in traffic volume and traffic load year by year, a large number of such bridges have suffered from various diseases and damages, which has also led to a gradual decline in bearing capacity.

[0003] If these bridges are demolished and rebuilt, it will not only consume a lot of financial and human resources, but also cause great waste and increase the social burden. A reasonable approach is to reinforce and renovate these bridges to restore and improve their bearing capacity.

[0004] Around the world, new technologies for the reinforcement and reconstruction of old bridges have always been an important topic in the field of bridge engineering research. At present, the commonly used reinforcement and reconstruction technologies for concrete simply supported T-beam bridges at home and abroad mainly include increasing the cross-section reinforcement method, gluing steel plates, gluing fiber belts, prestressed reinforcement method, changing the structural system reinforcement method, increasing the lateral integrity reinforcement method, etc. These reinforcement and reconstruction technologies have their advantages, disadvantages and different applicable occasions.

[0005] (1) Strengthening by increasing the cross section

[0006] The method of increasing the cross-section reinforcement is a traditional reinforcement method, which includes two methods: the bridge deck reinforcement layer reinforcement method and the method of increasing the main beam section. The bridge deck reinforcement layer reinforcement method is a method of re-casting a layer of reinforced concrete reinforcement layer after the old bridge deck has been treated in a certain way, so that it forms a combined structure with the original bridge span structure; the method of increasing the main beam section reinforcement method is a reinforcement method that increases the cross-sectional area of ​​the T-beam and adds ordinary steel bars (load-bearing steel bars or structural steel bars) to improve the bearing capacity, stiffness and durability of the T-beam; for concrete simply supported T-beams, the bottom single-side rectangular enlargement, the bottom horseshoe enlargement, or the simultaneous enlargement of the bottom and both sides of the web can be adopted.

[0007] (2) Steel plate reinforcement method

[0008] The steel plate bonding reinforcement method is to use adhesive to bond the steel plate to the bottom surface of the concrete T-beam web and fasten it with anchor bolts so that the steel plate and the concrete T-beam are firmly integrated, thereby improving the bearing capacity and stiffness of the T-beam.

[0009] (3) Fiber tape reinforcement method

[0010] The fiber tape reinforcement method is to stick the fiber composite material in strip shape to the bottom surface of the web of the T beam, so as to improve the bearing capacity and stiffness of the T beam. Compared with the steel plate reinforcement method, the fiber tape reinforcement method is more convenient to construct.

[0011] (4) Prestressed reinforcement method

[0012] Generally, steel tie rods or struts are added to the outside of the T-beam and anchored to the reinforced T-beam. Then prestress is applied to change the internal force distribution of the original T-beam structure and reduce the stress level of the original structure, which significantly improves the bearing capacity of the structure, reduces structural deformation, and reduces crack width.

[0013] (5) Changing the structural system reinforcement method

[0014] The reinforcement method is to change the force system of the simply supported T-beam bridge structure by adding supporting structures, changing the simply supported structure to a continuous structure, etc., so as to improve the force on the T-beam section and change the internal force distribution and force transmission path. There are many such reinforcement methods applied to highway concrete simply supported T-beam bridges, and the commonly used ones include the following:

[0015] ① Change the simply supported beam bridge deck to a continuous bridge deck structure: first remove the concrete pavement of the bridge deck, and then connect the bridge decks of the two simply supported beams by anchoring steel plates and stress-bearing steel bars at the ends of the two adjacent beams to form a so-called "quasi-continuous" structure.

[0016] ② Change the simply supported beam into a continuous structure: that is, set reinforced concrete piers on both sides of the pier or in the middle of the span of the bridge hole, and place rubber bearings on the top of the pier as needed. After adding support points, the simply supported structure becomes a continuous structure.

[0017] ③ Change the simply supported beam into a braced rigid frame: set an eight-shaped brace within the span of the simply supported beam so that the beam and the brace bear the load together.

[0018] (6) Adding transverse integral reinforcement method

[0019] A reinforcement method that improves the distribution of lateral loads on T-beam bridge structures by strengthening lateral connections, thereby increasing the overall stiffness of the structure.

[0020] The above-mentioned reinforcement and renovation technologies have currently formed relevant technical standards and specifications systems, such as my country's current "Highway Bridge Reinforcement Design Specifications" (JTGT J22-2008), "Highway Bridge Reinforcement Construction Technical Specifications" (JTGT J23-2008), and "Urban Bridge Structure Reinforcement Technical Code" (CJJ / T 239-2016).

[0021] At present, among the commonly used reinforcement methods, the steel plate bonding reinforcement method is to use adhesive to bond the steel plate to the bottom surface of the concrete T-beam web and fasten it with anchor bolts, so that the steel plate and the concrete T-beam are firmly integrated, thereby improving the bearing capacity and stiffness of the T-beam; however, in actual engineering applications, this method has the following main shortcomings: 1) When implementing the anchor bolt holes of the bottom steel plate, it is necessary to avoid the bottom longitudinal reinforcement, which is inconvenient for construction; 2) The pre-pressure of the adhesive between the steel plate and the concrete before curing is insufficient, which affects the reinforcement effect; 3) The steel plate is easy to rust, has poor durability, and has high subsequent maintenance costs; 4) After the steel plate bonding reinforcement, the stiffness and bearing capacity of a single T-beam are improved, but there is a lack of connection between the T-beams, and the integrity of the bridge is poor. Summary of the invention

[0022] The technical problem to be solved by the present invention is to provide a reinforcement system and a reinforcement method for converting a T-beam into a box beam by gluing a steel plate, which can reduce or avoid the bond damage between the steel plate and the concrete, and by transforming the T-beam into small box beams distributed at intervals along the longitudinal or transverse direction of the bridge, not only can the bending resistance and bearing capacity of the T-beam be improved and enhanced, but also the overall stress performance of the superstructure can be improved and enhanced, while reducing the construction difficulty and reducing the later maintenance.

[0023] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0024] The reinforcement system for converting a box beam by gluing a steel plate to a T beam of the present invention is characterized by comprising: a reinforcing steel plate glued to the bottom of the web of the T beam; a plurality of pressurized fixing units arranged at intervals at the bottom of the web of the T beam, each pressurized fixing unit comprising an angle steel and a pressurized steel plate; and a connecting steel plate for connecting adjacent T beams; the connecting steel plate is arranged in sections along the longitudinal bridge direction and clamped between the angle steel and the pressurized steel plate;

[0025] The reinforcing steel plate is adhered to the bottom of the T-beam web by structural adhesive;

[0026] The first right-angle surface of the angle steel is fixedly connected to the two side walls of the lower part of the web of each T-beam by anchor bolts and structural adhesive;

[0027] The pressure steel plate is arranged below the reinforcing steel plate, and the two ends of the pressure steel plate are respectively fixed to the second right-angle surfaces of two angle steels on the same T-beam web by bolts, and the side of the connecting steel plate is clamped between the second right-angle surface of the angle steel on the inner wall surface of the T-beam web and the pressure steel plate.

[0028] Preferably, the reinforcing steel plates and the connecting steel plates are weathering steel.

[0029] Preferably, the angle steels are arranged at equal intervals along the longitudinal bridge direction, and the first right-angle surface and the second right-angle surface of the angle steel are each provided with two holes, wherein the holes on the first right-angle surface are all elliptical; and the holes on the second right-angle surface are all circular.

[0030] Preferably, the pressurized steel plates are arranged at equal intervals along the longitudinal bridge direction, and are provided with four holes, which respectively correspond to the arrangement positions of the circular holes of the angle steel.

[0031] Preferably, the connecting steel plate is spliced ​​in sections in the longitudinal direction of the bridge; four holes are arranged on the connecting steel plate, which respectively correspond to the positions of the holes of the angle steel and the pressure steel plate;

[0032] Preferably, the connecting steel plate and the reinforcing steel plate and the joints between adjacent connecting steel plates are fixed by welding.

[0033] Preferably, the width of the connecting steel plate clamped between the angle steel and the pressurized steel plate is not shorter than the width of the second right-angle surface of the angle steel; the width of the connecting steel plate is equal to or longer than the spacing between the inner side walls of adjacent T-beam webs 1 .

[0034] The present invention also provides a reinforcement method for the reinforcement system based on the above-mentioned T-beam bonded steel plate conversion box beam, comprising the following steps:

[0035] Step 1: Fix the first right-angle surface of the angle steel to both sides of the lower part of the web of the T beam by anchor bolts and structural adhesive;

[0036] Step 2: Apply structural adhesive on the upper surface of the reinforcement steel plate, and stick the reinforcement steel plate to the bottom of the T-beam web with the structural adhesive; press the reinforcement steel plate with the pressure steel plate, and fasten it to the angle steels on both sides of the lower part of the T-beam web with bolts, and adjust the pre-pressure on the reinforcement steel plate by tightening the bolts;

[0037] Step 3: After the structural adhesive is cured to reach the design strength, remove the pressure steel plate, apply the structural adhesive on the second right-angle surface of the angle steel, i.e., the lower surface of the cantilever end, align the bolt holes of the connecting steel plate with the bolt holes on the angle steel, align the joint seams of the connecting steel plate and the reinforcement steel plate, and then paste them to the lower surface of the angle steel, and then temporarily fix them by spot welding; install the pressure steel plate, clamp the connecting steel plate between the angle steel and the pressure steel plate, and then tighten them with bolts;

[0038] Step 4: Weld and fix the joints between the connecting steel plate and the reinforcement steel plate, and between the connecting steel plates in sections.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] 1. The angle steel in the present invention is fixed on both sides of the lower part of the web of the T-beam. The bolt holes reserved on the first right-angle surface (fixing surface) of the angle steel are elliptical, which reserves sufficient space for avoiding the longitudinal reinforcement of the web of the T-beam when fixing the angle steel, thereby avoiding damage to the longitudinal reinforcement of the web.

[0041] 2. By tightening the bolts between the pressure steel plate and the angle steel, the reinforcement steel plate is actively provided with support force and pre-pressure is applied, which can ensure the reinforcement effect of the reinforcement steel plate.

[0042] 3. The T-beam web, reinforcement steel plate and connection steel plate are connected together through a pressurized fixing unit, and the T-beam bridge is converted from a T-shaped section to a box section. Compared with the original structural form, the box section has greater torsional stiffness, the lateral force on the web is more uniform, and the overall force performance of the main beam is improved and enhanced.

[0043] 4. Both the reinforcement steel plates and the contact steel plates are made of weathering steel with good corrosion resistance and durability, and the subsequent maintenance costs are low.

[0044] 5. The present invention has a simple structure, light reinforcement parts, no need for large-scale construction machinery, simple construction process, short construction period, easy control of construction quality, low full-life cost, can restore and improve the bending stiffness and bearing capacity of the main beam, and improve and enhance the overall stress performance of the T-beam bridge. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a three-dimensional schematic diagram of the assembly of a reinforcement system for converting a T-beam into a box beam by gluing a steel plate to the present application;

[0046] Figure 2 This is a front view of a reinforcement system for converting a T-beam into a box beam by gluing a steel plate to the present application;

[0047] Figure 3 yes Figure 2 A magnified view of part A;

[0048] Figure 4 It is a three-dimensional structural diagram of the contact steel plate;

[0049] Figure 5 It is a three-dimensional structural diagram of angle steel;

[0050] Figure 6 It is a schematic diagram of the three-dimensional structure of the pressurized steel plate;

[0051] Figure 7is the load-displacement curve of the mid-span section;

[0052] Legend:

[0053] 1—T beam web; 2—reinforcement steel plate;

[0054] 3—Contact steel plate; 4—Angle steel;

[0055] 5—pressure steel plate; 6—anchor bolt;

[0056] 7—bolt; 8—structural adhesive;

[0057] 9—weld; 10—anchor hole;

[0058] 11—bolt hole. 401—first right angle surface

[0059] 402—Second right-angled surface. DETAILED DESCRIPTION

[0060] In order to make the above-mentioned objects, features and advantages of the present application more easily understood, the present invention is further described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0061] refer to Figure 1 As shown, a reinforcement system for converting a T-beam into a box beam by gluing a steel plate comprises a reinforcing steel plate 2 glued to the bottom of a T-beam web 1, the width of the reinforcing steel plate 2 is equivalent to the width of the bottom surface of the T-beam web 1, one or more reinforcing steel plates 2 are arranged along the length direction of the T-beam web 1 in the longitudinal direction of the bridge, and the reinforcing steel plates 2 are glued to the bottom surface of the T-beam web 1 by means of a structural adhesive 8; pressurized fixing units are arranged at intervals at the bottom of the T-beam web 1, each pressurized fixing unit comprises an angle steel 4 and a pressurized steel plate 5, and a connecting steel plate 3 for connecting adjacent T-beams, and the pressurized steel plate 5 and the connecting steel plate 3 are both rectangular plates; the connecting steel plate 3 is arranged in sections along the longitudinal direction of the bridge and clamped between the angle steel 4 and the pressurized steel plate 5;

[0062] Specifically, the first right-angle surface (fixed surface) 401 of the angle steel 4 is fixedly connected to the two side wall surfaces of the lower part of each T-beam web 1 by anchor bolts 6 and structural adhesive 8; the pressure steel plate 5 is arranged below the reinforcing steel plate 2, and the two ends of the pressure steel plate 5 are respectively fixed to the second right-angle surfaces (cantilever surfaces) 402 of the two angle steels 4 on the same T-beam web 1 by bolts 7, and the side of the connecting steel plate 3 is clamped between the second right-angle surface of the angle steel 4 on the inner wall surface of the T-beam web 1 and the pressure steel plate 5.

[0063] In order to improve the durability of the steel plate and reduce subsequent maintenance, the steel material used for the reinforcement steel plate 2 and the connection steel plate 3 is weathering steel.

[0064] Combination Figure 1 , Figure 2 and Figure 5In this specific implementation method, for the convenience of construction, the angle steels 4 are arranged at equal intervals along the longitudinal bridge direction, which can ensure their effective support and prestressing effect on the reinforced steel plate 2; the two right-angled surfaces of the angle steel 4 are each provided with two holes. To ensure that there is enough space to avoid the longitudinal reinforcement of the web when installing the angle steel 4, the anchor hole 10 on the first right-angled surface is set to an elliptical shape, and the bolt hole 11 on the second right-angled surface is set to a circular shape; to ensure that the angle steel is firmly fixed, the first right-angled surface of the angle steel 4 is anchored to the two side wall surfaces of the lower part of the T-beam web 1 by anchor bolts 6 and structural adhesive 8; the bottom surface of the second right-angled surface of the angle steel 4 is kept flush with the bottom of the T-beam web 1.

[0065] Combination Figure 1 , Figure 2 and Figure 6 In this specific embodiment, the pressure steel plate 5 is arranged at equal intervals along the longitudinal bridge direction, and four bolt holes 11 are arranged thereon, and the positions of the bolt holes 11 correspond to the positions of the bolt holes of the angle steel 4; the reinforcing steel plate 2 is tightened by the pressure steel plate 5, and is fastened to the angle steels 4 on both sides of the lower part of the T-beam web 1 by bolts 7; the pre-pressure of the reinforcing steel plate 2 is adjusted by tightening and loosening the bolts 7, thereby ensuring the support and bonding effect of the reinforcing steel plate 2.

[0066] Combination Figure 1 , Figure 2 and Figure 4 In this specific implementation method, considering that the longitudinal length of the bridge is generally long, in order to reduce the hoisting weight and facilitate construction, the connecting steel plate 3 is spliced ​​in sections along the longitudinal direction of the bridge; four bolt holes 11 are provided on the connecting steel plate 3, which correspond to the arrangement positions of the bolt holes 11 of the angle steel 4 respectively; in order to ensure that the installation is firm and the splicing seam is tightly connected, when installing the connecting steel plate 3, structural glue 8 is applied to the lower surface of the second right-angle surface (i.e., the cantilever side) of the angle steel 4, and the connecting steel plate 3 is pasted to the lower surface of the cantilever side of the angle steel 4, and it is tightened with a pressure steel plate 5, and fastened to the angle steel 4 by bolts 7; the remaining adjacent splicing parts are fixed by welding, and the connecting steel plate 3 and the reinforcing steel plate 2 and the adjacent connecting steel plates 3 are closely connected through the weld 9, thereby forming a force-bearing whole.

[0067] In order to improve the supporting effect of the connecting steel plate 3, the width of the connecting steel plate 3 clamped between the angle steel 4 and the pressure steel plate 5 is not shorter than the width of the second right-angle surface of the angle steel 4, and the width of the connecting steel plate is equal to or longer than the spacing between the inner side walls of adjacent T-beam webs 1.

[0068] In order to improve the mechanical properties, a recessed groove is punched between the bolt holes 11 on both sides of the connecting steel plate 3. The length of the recessed groove is shorter than the spacing between the bolt holes 11 on both sides, and the width is 1-5 cm. 3-5 recessed grooves can be set on a connecting steel plate 3.

[0069] The present invention also provides a reinforcement method for the reinforcement system based on the above-mentioned T-beam bonded steel plate conversion box beam, comprising the following steps:

[0070] Step 1: Fix the first right-angle surface of the angle steel 4 to the two side wall surfaces of the lower part of the T-beam web 1 by means of anchor bolts 6 and structural adhesive 8.

[0071] Step 2: Apply structural adhesive 8 on the upper surface of the reinforcing steel plate 2, adhere the reinforcing steel plate 2 to the bottom of the T-beam web 1 through the structural adhesive 8, then tighten the reinforcing steel plate 2 through the pressure steel plate 5, and fasten it to the angle steels 4 on both sides of the lower part of the T-beam web 1 through bolts 7, and adjust the pre-pressure on the reinforcing steel plate 2 by tightening and loosening the bolts 7.

[0072] Step 3: After the structural adhesive 8 is cured and reaches the designed strength, remove the pressure steel plate 5, apply the structural adhesive 8 on the lower surface of the second right-angle surface (i.e., the cantilever end) of the angle steel, align the bolt holes 11 of the connecting steel plate 3 with the bolt holes on the angle steel 4, align the joints between the connecting steel plate 3 and the reinforcing steel plate 2, and then stick them to the lower surface of the angle steel 4, and then temporarily fix them by spot welding; install the pressure steel plate 5, clamp the connecting steel plate 3 between the angle steel 4 and the pressure steel plate 5, and then tighten them with bolts 7.

[0073] Step 4: Weld and fix the joints between the connecting steel plate 3 and the reinforcing steel plate 2, and between the connecting steel plates 3 and the connecting steel plates 3 in sections.

[0074] At this point, the conversion from T-beam to box beam is completed. The T-beam, reinforcement steel plate and connecting steel plate are connected through the above-mentioned reinforcement system to form a box-shaped structure with better overall stress performance.

[0075] The present invention proposes a reinforcement system and a reinforcement method for converting a T-beam into a box beam by gluing a steel plate, which not only restores and improves the bending stiffness and bearing capacity of the T-beam, but also completes the conversion of the T-section of the T-beam bridge to a box section. The reinforcement steel plate 2 and the connecting steel plate 3 are connected by the reinforcement system to form a box-shaped structure with better overall stress performance, so that the overall stress performance of the main beam is further improved and enhanced; at the same time, the steel plate is made of weathering steel and is installed in sections, which can not only reduce the difficulty of construction, but also reduce later maintenance.

[0076] The following is a comparative analysis of the advantages and disadvantages of the commonly used reinforcement and reconstruction technologies for concrete T-beam bridges and the new reinforcement and reconstruction technology proposed in this application.

[0077] Reinforcement and renovation technology Key Benefits Main Disadvantages Increased cross-section reinforcement method Can greatly improve the bearing capacity, rigidity and durability of T-beam The weight of the structure is increased; it is necessary to implant steel bars in the original T-beam, set up support formwork, tie up the new steel bars, and cast concrete in place, which takes a long time to construct. Steel plate reinforcement method The original structural system is basically kept unchanged, the construction is convenient, the construction period is short, and the bearing capacity and rigidity of the T-beam can be greatly improved. Steel plates are prone to rust, have poor durability, and require high maintenance costs Fiber tape reinforcement method The original structural system is basically kept unchanged, and the material is corrosion-resistant; the construction is convenient and the construction period is short; the bearing capacity of the T-beam can be greatly improved The fiber strength is too high relative to the elastic modulus, and the material utilization rate is low during normal use Prestressed reinforcement method It is an active reinforcement method that can change the internal force distribution of the original T-beam structure and reduce the effect of the original structure's dead load; it can significantly increase the structural stiffness and reduce the crack width. The anchor system is inconvenient to install and construct, and the space for tensioning the steel cable may be limited; there may be undesirable phenomena such as excessive anti-arching and cracking of the upper flange under tension; there are corrosion problems with the external prestressed steel bars Changing the structural system reinforcement method Changing the structural system can significantly improve the structural stress and significantly reduce the bending moment effect of the original control section of the T-beam structure. Traffic needs to be interrupted and the bridge deck needs to be repaired. Negative bending steel bars and cast-in-place concrete need to be added to the upper flange of the T-beam between the two spans. The construction period is long. The added deadweight of the structure is large, and the shear bearing capacity of the beam end may be insufficient. Increase the lateral integrity reinforcement method Can improve the overall stiffness of the T-beam structure The improvement of T-beam bearing capacity is limited Reinforcement and transformation technology of the present invention By changing the cross-sectional form of the upper structure, the structural system is changed. By strengthening the lateral connection, the overall stress performance of the upper structure is significantly improved and enhanced, and the bearing capacity and stiffness of the T beam can be restored or greatly improved. At the same time, the construction is convenient and the construction period is short. The material is corrosion-resistant and the subsequent maintenance cost is low. The amount of steel used is relatively large compared to the pasted steel plate

[0078] It can be seen from the above that the present invention can greatly improve the stiffness and bearing capacity of the existing concrete simply supported T-beam bridge without affecting traffic, and the construction is simple and convenient, and the full life cost is low. Compared with the currently commonly used reinforcement and reconstruction technology, the characteristics and innovations of the technology of this application are:

[0079] (1) At the structural level, the uniform cross-section T-beam of the entire bridge is transformed into a part of small box beams + a part of uniform cross-section T-beams, thereby forming a variable cross-section structure with more reasonable stress.

[0080] (2) In terms of construction, the steel plate bonding reinforcement technology is adopted, which does not require construction operations such as formwork and concrete pouring, does not require large-scale construction equipment, has a simple construction process, a short construction period, and is easy to control construction quality;

[0081] (3) In terms of post-maintenance, weathering steel with good corrosion resistance and durability is used, and the post-maintenance cost is low.

[0082] The following is a comparative analysis of the reinforcement effect of the present invention and the traditional steel plate bonding reinforcement method.

[0083] Taking an ordinary highway prestressed concrete simply supported T-beam bridge as an example, the bridge superstructure consists of 4 T-beams, the bridge deck width is 7.7m, the T-beam height is 2m, and the bridge length is 30m. In order to compare the difference in reinforcement effect between the reinforcement scheme using the bonded steel plate and the reinforcement scheme of the present invention, a concentrated load is applied to the cross section of the span until the structure is destroyed. The load-displacement curve is as follows: Figure 7 As shown; it can be seen from the figure that the ultimate bearing capacity of the reinforcement scheme of the present invention is greatly improved compared with the other two schemes. For the same 1 cm thick steel plate, the ultimate bearing capacity is increased by 41% compared with the glued steel plate scheme; at the same time, it can be seen from the figure that the slope of the curve of the present invention is the largest, reflecting that the reinforcement scheme of the present invention greatly improves the overall stiffness, and under the same load, the deformation of the structure is greatly reduced.

[0084] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A reinforcement system for converting T-beams into box girders by gluing steel plates. Features: It comprises a reinforcing steel plate (2) adhered to the bottom of a T-beam web (1); a plurality of pressurizing fixing units arranged at intervals at the bottom of the T-beam web (1), each pressurizing fixing unit comprising an angle steel (4) and a pressurizing steel plate (5); and a connecting steel plate (3) for connecting adjacent T-beams; the connecting steel plate (3) is arranged in sections along the longitudinal bridge direction and clamped between the angle steel (4) and the pressurizing steel plate (5); The reinforcing steel plate (2) is adhered to the bottom of the T-beam web (1) by means of structural adhesive (8); The first right-angled surface of the angle steel (4) is fixedly connected to the wall surfaces on both sides of the lower part of each T-beam web (1) by means of anchor bolts (6) and structural adhesive (8); The pressurized steel plate (5) is arranged below the reinforcing steel plate (2), and the two ends of the pressurized steel plate (5) are respectively fixed to the second right-angled surfaces of two angle steels (4) on the same T-beam web (1) by bolts (7), and the side of the connecting steel plate (3) is clamped between the second right-angled surfaces of the angle steels (4) on the inner wall surface of the T-beam web (1) and the pressurized steel plate (5); The connecting steel plate (3) is spliced ​​in sections in the longitudinal direction of the bridge; four holes are provided on the connecting steel plate (3), which respectively correspond to the positions of the holes of the angle steel (4) and the pressure steel plate (5); the connecting steel plate (3) is fixed to the joints of the reinforcing steel plate (2) and the adjacent connecting steel plates (3) by welding; the width of the connecting steel plate (3) clamped between the angle steel (4) and the pressure steel plate (5) is not shorter than the width of the second right-angled surface of the angle steel (4); the width of the connecting steel plate is equal to or longer than the spacing between the inner side walls of adjacent T-beam webs.

2. The reinforcement system for converting box beams by gluing steel plates to T beams according to claim 1, Features: The reinforcing steel plate (2) and the connecting steel plate (3) are weathering steel.

3. The reinforcement system for converting a T-beam into a box beam by gluing a steel plate according to claim 1 or 2, Features: The angle steels (4) are arranged at equal intervals along the longitudinal direction of the bridge, and the first right-angled surface and the second right-angled surface of the angle steel (4) are each provided with two holes, wherein the holes in the first right-angled surface are all elliptical, and the holes in the second right-angled surface are all circular.

4. The reinforcement system for converting a T-beam into a box beam by gluing a steel plate according to claim 3, Features: The pressurized steel plates (5) are arranged at equal intervals along the longitudinal bridge direction, and are provided with four holes, the four holes corresponding to the arrangement positions of the circular holes of the angle steel (4).

5. A method for reinforcing a reinforcing system for converting a T-beam into a box beam by gluing a steel plate according to any one of claims 1 to 4, It is characterized in that The following steps are involved: Step 1: fix the first right-angle surface of the angle steel (4) to both sides of the lower part of the T-beam web (1) by means of anchor bolts (6) and structural adhesive (8); Step 2: Apply structural adhesive (8) on the upper surface of the reinforcing steel plate (2), and adhere the reinforcing steel plate (2) to the bottom of the T-beam web (1) by means of the structural adhesive (8); compress the reinforcing steel plate (2) by means of the pressure steel plate (5), and fasten the reinforcing steel plate (2) to the angle steels (4) on both sides of the lower part of the T-beam web (1) by means of bolts (7), and adjust the pre-pressure on the reinforcing steel plate (2) by tightening the bolts (7); Step 3: After the structural adhesive (8) is cured to reach the designed strength, the pressure steel plate (5) is removed, and the structural adhesive (8) is applied to the second right-angle surface of the angle steel (4), i.e., the lower surface of the cantilever end, and the bolt holes (11) of the connecting steel plate (3) are aligned with the bolt holes on the angle steel (4), and the joint seams of the connecting steel plate (3) and the reinforcing steel plate (2) are aligned, and then they are pasted to the lower surface of the angle steel (4), and then temporarily fixed by spot welding; the pressure steel plate (5) is installed, and the connecting steel plate (3) is clamped between the angle steel (4) and the pressure steel plate (5), and then fastened with bolts (7); Step 4: welding and fixing the joints between the connecting steel plate (3) and the reinforcing steel plate (2) and between the connecting steel plates (3) and the connecting steel plates (3) in sections.

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