Novel structure for reinforcing old T beam by adopting UHPC thin layer
By installing reinforcement components on the web and horseshoe section of the old T-beam and covering them with a thin layer of UHPC, combined with prestressed tendons and specific steel plate connections, the problems of complex construction and poor durability of old T-beam bridge reinforcement were solved, and efficient improvement of shear and bending bearing capacity was achieved.
Patent Information
- Application Number
- CN202423210885.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-24
- Publication Date
- 2025-11-28
- Estimated Expiration
- 2034-12-24
AI Technical Summary
In the existing technology, the reinforcement methods for old T-beam bridges have problems such as complex construction, poor durability, increased self-weight, low reinforcement efficiency and mismatch with stress characteristics. Conventional reinforcement methods cannot effectively improve the bending and shear bearing capacity.
A novel structure for reinforcing old T-beams using UHPC thin-layer reinforcement is developed. This structure involves installing reinforcement components on the web and horseshoe-shaped part of the old T-beam and encasing them in a UHPC thin layer to form an integral structure. Combined with prestressed tendons and a specially designed steel plate connection method, this enhances the shear and bending bearing capacity.
It improves the shear and bending bearing capacity of the old T-beams, extends the service life of the reinforcement components, reduces maintenance costs, enhances the durability and construction efficiency of the structure, and conforms to the stress characteristics of T-beams.
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Figure CN223607769U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to bridge maintenance technical field, concretely relates to a new structure of old T beam reinforced with UHPC thin layer. BACKGROUND
[0002] By the end of 2023, statistical data shows that the total number of highway bridges in China is 107.93 million, and the total mileage is 9528.82 million. The cross-sectional shape of the T beam bridge is T-shaped. Compared with the traditional rectangular beam, its cross-sectional area is smaller, so it needs less concrete, can reduce the self-weight of the component, improve the crossing capacity, and the appearance is simple and easy to manufacture. The above advantages make the T beam become an important bridge structure form. With the development of urbanization and economy, the traffic load is increasing, and the load borne by the bridge is also increasing. The old T beam bridge constructed in the early stage cannot adapt to the existing traffic load, and many diseases are found in the operation process. At present, a large number of old T beam bridges need to be repaired and reinforced. By adding a UHPC thin layer at the beam end and the bottom of the midspan of the T beam and tensioning the prestressed steel bars at the beam bottom, a new structure of old T beam reinforced with UHPC thin layer is formed. This structure can effectively improve the bending and shear bearing capacity of the T beam, has the advantages of high strength, durability, good economy, high reinforcement efficiency, and has wide application prospect.
[0003] In the prior art, T beam reinforcement mainly adopts the methods of increasing section reinforcement, sticking steel plate reinforcement, external prestress reinforcement and conventional UHPC thin layer reinforcement. The reinforcement effect of the conventional sticking steel plate reinforcement method depends largely on the adhesive process and construction process level, and the improvement of the stiffness and crack resistance of the reinforced structure is limited. The durability is poor, the service life is not long, and the conventional sticking steel plate reinforcement method has the problems of exposed steel plate, easy to be oxidized and corroded by air, etc. The construction period of the increasing section reinforcement method is long and the construction process is complex, which requires a series of concrete construction related process procedures such as formwork, vibration, pouring, curing, etc. The construction process is complicated. The increasing section reinforcement method will significantly increase the self-weight of the bridge, produce certain gravity effect, and the existence of stress hysteresis will reduce the bearing capacity of the newly added part, reduce the reinforcement efficiency, and the aging of the adhesive between the reinforcement layer and the existing structure will cause poor adhesion. The construction process of external prestress, the length and position of the bonding section in the steel strand blanking and threading, and the influence of the pre-stress between the new and old concrete on the original structure are difficult to determine. In addition, the failure phenomena such as relaxation and broken steel of external prestress are also common. The stress mode of the old T beam is large shear effect at the beam end and large bending moment effect at the midspan. The conventional UHPC thin layer reinforcement method usually adopts the mode of wrapping the T beam web with full section and arranging ordinary steel bars at the beam bottom. The full section wrapping form does not match the stress characteristics of the T beam, and the arrangement of steel bars has limited effect on the improvement of the bearing capacity of the T beam, which does not take advantage of UHPC (ultra-high performance concrete). It is urgent to innovate a new reinforcement structure.
[0004] In view of the above technical problems, the utility model provides a new structure. <Utility model content>
[0005] The utility model discloses to overcome above situation's insufficient, aims at providing a kind of technical scheme capable of solving at least one of the above problems.The utility model provides a new structure of reinforcing old T beam with UHPC thin layer, the web of old T beam is reinforced by setting reinforcing assembly, and UHPC thin layer is set to cover reinforcing assembly in it, make reinforcing assembly and UHPC thin layer form a whole, prevent reinforcing assembly from oxidation, corrosion and other problems due to direct exposure in external environment, can increase service life, reduce the cost of later maintenance.
[0006] To solve the above technical problems, the utility model provides a new structure of reinforcing old T beam with UHPC thin layer, old T beam is composed of web and flange plate shaped on the top of web, the bottom of web is horseshoe part, and the new structure of reinforcing old T beam includes UHPC thin layer for covering the two sides of web and horseshoe part, and reinforcing assembly symmetrically arranged on the two sides of web for fixing UHPC thin layer after pouring and shaping on old T beam, UHPC thin layer covers reinforcing assembly in it after shaping, and makes reinforcing assembly and UHPC thin layer form a whole.
[0007] The new structure of reinforcing old T beam with UHPC thin layer as described above, the fixing assembly for fixing the reinforcing assembly on the web is arranged in the web, and the reinforcing assembly and fixing assembly are covered in the UHPC thin layer after shaping.
[0008] The new structure of reinforcing old T beam with UHPC thin layer as described above, the reinforcing assembly includes two horizontally arranged steel plates spaced apart on the web and a plurality of vertical steel plates for connecting the two horizontally arranged steel plates.
[0009] The new structure of reinforcing old T beam with UHPC thin layer as described above, the fixing assembly includes a plurality of anchor bolts arranged on the web, and the two ends of the anchor bolt are connected with the horizontally arranged steel plates on the two sides of the web.
[0010] The new structure of reinforcing old T beam with UHPC thin layer as described above, the vertical steel plate is arranged on the horizontally arranged steel plate to form a gap between the vertical steel plate and the web.
[0011] The new structure of reinforcing old T beam with UHPC thin layer as described above, the cross section of the vertical steel plate is T-shaped.
[0012] The new structure of reinforcing old T beam with UHPC thin layer as described above, the UHPC thin layer at the horseshoe part is provided with a prestressed tendon arranged along the length direction of the UHPC thin layer.
[0013] The material of the transverse steel plate and the vertical steel plate is Q355C steel.
[0014] The transverse steel plate and the vertical steel plate are connected through welding.
[0015] The UHPC thin layer comprises a horseshoe layer for covering the horseshoe part and web layers arranged on both sides of the web, respectively, the bottom of the web layer is connected with the horseshoe layer in one piece, the middle part of the web layer has an inverted trapezoidal notch for dividing the web layer into front and rear parts, the web layer of the front part and the web layer of the rear part are both provided with reinforcing assemblies, and the corresponding web layers are both provided with fixing assemblies for connecting the reinforcing assemblies on both sides of the web.
[0016] Compared with the prior art, the novel structure for reinforcing the old T beam through the UHPC thin layer has the following advantages:
[0017] 1. The novel structure for reinforcing the old T beam through the UHPC thin layer can cover the reinforcing assemblies in the UHPC thin layer after forming, so that the problems of oxidation and corrosion of the reinforcing assemblies caused by direct exposure to the external environment can be prevented, the service life can be prolonged, and the cost of later maintenance can be reduced.
[0018] 2. The UHPC thin layer and the reinforcing assemblies form an integral whole after forming, so that the strength of the whole fixing assembly is strengthened, and the shear bearing capacity of the whole T beam is improved.
[0019] 3. The prestressed tendon arranged in the UHPC thin layer can effectively improve the bearing capacity of the old T beam and the crack resistance of the reinforced structure after forming of the UHPC thin layer, the durability is good, and the workload of later maintenance is small.
[0020] 4. The web layer is divided into two parts through the inverted trapezoidal notch, the horseshoe layer in the horseshoe part is reserved, and the reinforcing assemblies are arranged on both ends of the T beam, so that the novel structure for reinforcing the old T beam is more suitable for the stress characteristics of the T beam, the shear bearing capacity of the beam end is improved, the bending bearing capacity of the span is improved, the self weight of the span is small, and the reinforcing efficiency is improved. BRIEF DESCRIPTION OF DRAWINGS
[0021] The specific embodiments of the utility model will be further described in detail below with reference to the drawings, in which:
[0022] Figure 1 is a structural schematic view of the utility model.
[0023] Figure 2 is another structural schematic view of the utility model.
[0024] Figure 3 is a structural schematic view of the reinforcing assembly in the utility model.
[0025] Figure 4 is another structural schematic view of the reinforcing assembly in the utility model.
[0026] Figure 5 is a structural schematic view of the fixing assembly in the utility model.
[0027] Figure 6 is a structural schematic view of the UHPC thin layer in the utility model.
[0028] In the drawing: 1, old T beam; 10, web plate; 11, flange plate; 12, horseshoe part;
[0029] 2, UHPC thin layer; 20, horseshoe layer; 21, web plate layer; 22, inverted trapezoidal notch;
[0030] 3, reinforcing assembly; 30, transverse steel plate; 31, vertical steel plate;
[0031] 4, fixing assembly; 40, counter-pulling anchor bolt; 5, prestressed tendon.
DETAILED DESCRIPTION
[0032] The embodiments of the utility model will be described in detail below with reference to the drawings.
[0033] As shown in Figures 1-6 the utility model discloses a kind of new structure of UHPC thin layer reinforcing old T beam, old T beam 1 is composed of web plate 10 and the flange plate 11 shaped in the top of web plate 10, the bottom of web plate 10 is horseshoe part 12, the new structure of reinforcing old T beam 1 includes the UHPC thin layer 2 for covering the two sides of web plate 10 and horseshoe part 12 formed by pouring, and reinforcing assembly 3 for fixing UHPC thin layer 2 after pouring shaping on old T beam 1 is symmetrically arranged on the two sides of web plate 10, UHPC thin layer 2 is covered in reinforcing assembly 3 after shaping, and make reinforcing assembly 3 and UHPC thin layer 2 form an entirety.The new structure of reinforcing old T beam of the application, compared with conventional UHPC thin layer 2 reinforcing method, UHPC thin layer 2 of the application can be covered in reinforcing assembly 3 after shaping, avoid reinforcing assembly 3 exposed, prevent reinforcing assembly 3 from oxidizing after contacting with air, can increase service life, reduce the cost of later maintenance.In addition, UHPC thin layer 2 forms an entirety with reinforcing assembly 3 after shaping, can strengthen the shear capacity of entire T beam.It needs to be explained that, in the application, UHPC thin layer 2 adopts ultra-high performance concrete U120, cubic compressive strength standard value fcu,k ≥ 120 Mpa, axial compressive strength standard value f ck ≥ 84 Mpa. For, UHPC thin layer 2 uses super high performance concrete U120, which has excellent bonding performance, UHPC thin layer 2 and old T beam 1 structure contact surface does not need to be coated with adhesive to achieve excellent interface connection, omitting the step of needing to coat the adhesive, improving the construction efficiency, while also avoiding the aging problem of the adhesive, making the durability of the reinforced structure better.
[0034] As shown in Figures 3 to 5 , as a further scheme of the present embodiment, the web plate 10 is provided with a fixing assembly 4 for fixing the reinforcing assembly 3 on both sides of the web plate 10, and the UHPC thin layer 2 is formed after the reinforcing assembly 3 and the fixing assembly 4 are covered therein. By setting the fixing assembly 4, the reinforcing assembly 3 on both sides of the web plate 10 can be connected into a whole, and the reinforcing structure is more reliable.
[0035] As shown in Figures 3 to 5 , as a further scheme of the present embodiment, the reinforcing assembly 3 includes two transverse steel plates 30 transversely arranged on the web plate 10 and a plurality of vertical steel plates 31 located between the two transverse steel plates 30 for connecting the two transverse steel plates 30, and the materials of the transverse steel plates 30 and the vertical steel plates 31 are Q355C steel. The fixing assembly 4 includes a plurality of anchor bolts 40 arranged on the web plate 10, and the two ends of the anchor bolt 40 are respectively connected with the transverse steel plates 30 on both sides of the web plate 10. In the present embodiment, the transverse steel plates 30 on both sides of the web plate 10 are fixed by the anchor bolts 40 to form a whole, and the whole fixing assembly 4 is fixed on the web plate 10, and after the UHPC thin layer 2 is formed, the reinforcing assembly 3, the fixing assembly 4 and the UHPC thin layer 2 can form a whole to reinforce the structure of the old T beam 1.
[0036] As shown in Figure 4 , 5 , in the present embodiment, the transverse steel plates 30 and the vertical steel plates 31 are connected by welding, and the cross section of the vertical steel plate 31 is T-shaped, which can greatly improve the shear bearing capacity of the whole reinforcing assembly 3, avoid shear failure and improve the safety of the structure.
[0037] As shown in Figures 3 to 5 , as a further scheme of the present embodiment, the vertical steel plates 31 are erected on the transverse steel plates 30 so that there is a gap between the vertical steel plates 31 and the web plate 10, and after the vertical steel plates 31 are erected on the transverse steel plates 30, there is a gap between the vertical steel plates 31 and the side surface of the web plate 10. After pouring concrete, the concrete can flow into the gap, and after the concrete is formed, it can form a whole with the reinforcing assembly 3, and the reinforcing assembly 3 is completely embedded in the UHPC thin layer 2.
[0038] AsFigure 1 As shown, as a further scheme of the present embodiment, the UHPC thin layer 2 at the horseshoe part 12 is provided with prestressed tendons 5 arranged along the length direction of the UHPC thin layer 2. In the present embodiment, when installing the prestressed tendons 5, a tensioning jack device is installed at both ends of the prestressed tendons 5 to apply a pre-tension to the prestressed tendons 5. After the UHPC thin layer 2 reaches 80% strength, the tensioning jack device is released. The formed UHPC thin layer 2 reinforced structure can effectively improve the bearing capacity of the old T-beam 1, improve the crack resistance of the reinforced structure, has good durability, and has small later maintenance workload. In the present embodiment, the prestressed tendons 5 are high-strength and low-strain steel bars. A certain pre-tension is applied to the steel bars during production, so the steel bars have high bearing capacity, and the tensile strength is ≥ 1860 Mpa.
[0039] As shown in Figure 1 , Figure 6 As shown, as a further scheme of the present embodiment, the UHPC thin layer 2 includes a horseshoe layer 20 covering the horseshoe part 12 and web layers 21 arranged on both sides of the web 10. The bottom of the web layer 21 is connected to the horseshoe layer 20 in one piece, and the middle part of the web layer 21 has an inverted trapezoidal notch 22 for dividing the web layer 21 into front and rear parts. The front web layer 21 and the rear web 10 are both provided with reinforcing assemblies 3, and the corresponding web layers 21 are both provided with fixing assemblies 4 connecting the reinforcing assemblies 3 on both sides of the web 10. In the present embodiment, the web layer 21 is divided into two parts by the inverted trapezoidal notch 22, and the horseshoe layer 20 in the horseshoe part 12 is retained. The reinforcing assemblies 3 are arranged on both ends of the T-beam, so that the new structure for reinforcing the old T-beam of the present application is more suitable for the stress characteristics of the T-beam. The shear bearing capacity of the beam end is improved, the bending bearing capacity of the midspan is improved, the self-weight of the midspan is small, and the reinforcing efficiency is high.
Claims
1. A new construction for reinforcing an old T-beam with thin layers of UHPC, the old T-beam (1) consisting of a web (10) and flange plates (11) shaped on top of the web (10), the bottom of the web (10) being a horseshoe part (12), characterized in that The new structure for reinforcing the old T beam (1) comprises a UHPC thin layer (2) formed by pouring for covering both sides of the web (10) and the horseshoe part (12), and a reinforcing assembly (3) symmetrically arranged on both sides of the web (10) for fixing the UHPC thin layer (2) after pouring to the T beam, the UHPC thin layer (2) covers the reinforcing assembly (3) after forming and makes the reinforcing assembly (3) and the UHPC thin layer (2) form an integral whole.
2. A new type of construction for strengthening old T-beams with UHPC thin layer according to claim 1, characterized in that, The web (10) is provided with a fixing assembly (4) for fixing the reinforcing assembly (3) on both sides of the web (10), and the UHPC thin layer (2) covers the reinforcing assembly (3) and the fixing assembly (4) after forming.
3. A new type of construction of strengthening old T-beams with UHPC thin layer according to claim 2, characterized in that The reinforcing assembly (3) comprises two transverse steel plates (30) arranged at intervals on the web (10) and a plurality of vertical steel plates (31) arranged between the two transverse steel plates (30) for connecting the two transverse steel plates (30).
4. A new type of construction of strengthening old T-beams with UHPC thin layer according to claim 3, characterized in that The fixing assembly (4) comprises a plurality of anchor bolts (40) arranged on the web (10), and the two ends of the anchor bolt (40) are connected with the transverse steel plates (30) on both sides of the web (10).
5. A new construction of strengthening old T-beam with UHPC thin layer according to claim 4, characterized in that The vertical steel plate (31) is arranged on the transverse steel plate (30) so that there is a gap between the vertical steel plate (31) and the web (10).
6. A new construction of strengthening old T-beam with UHPC thin layer according to claim 3, characterized in that The vertical steel plate (31) is T-shaped in cross section.
7. A new construction of strengthening old T-beam with UHPC thin layer according to claim 1, characterized in that The UHPC thin layer (2) at the horseshoe part (12) is provided with a prestressed tendon (5) arranged along the length direction of the UHPC thin layer (2).
8. A new construction of strengthening old T-beam with UHPC thin layer according to claim 3, characterized in that The material of the transverse steel plate (30) and the vertical steel plate (31) is Q355C steel.
9. A new construction of strengthening old T-beam with UHPC thin layer according to claim 3, characterized in that The transverse steel plate (30) and the vertical steel plate (31) are connected by welding.
10. A new construction of strengthening old T-beam with UHPC thin layer according to claim 1, characterized in that The UHPC thin layer (2) comprises a horseshoe layer (20) for covering the horseshoe part (12) and a web layer (21) arranged on both sides of the web (10), the bottom of the web layer (21) is connected with the horseshoe layer (20) as a whole, the middle part of the web layer (21) has an inverted trapezoidal notch (22) for dividing it into front and rear parts, the front and rear web layers (21) are provided with the fixing assembly (4), and the corresponding web layers (21) are provided with the fixing assembly (4) for connecting the reinforcing assembly (3) on both sides of the web (10).