Reinforced concrete beam reinforcing method based on high-strength steel bar and UHPC segmented pouring and formed reinforcing structure
Through the method of high-strength steel bars and UHPC segment casting, the problems of complex construction and insufficient durability of reinforced concrete beam reinforcement are solved, and convenient and efficient reinforcement effects are achieved, which are suitable for structural transformation of buildings and bridges.
Patent Information
- Application Number
- CN202510920967.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-04
- Publication Date
- 2025-08-12
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
The existing reinforced concrete beam reinforced methods have problems such as complex construction, insufficient durability, high cost, and limited load capacity improvement, especially under large spans or complex stress conditions, shrinkage cracks are easily generated.
The method of segmented casting of high-strength steel bars and UHPC is adopted, including pretreatment of beam bodies, implanting high-strength anchor bars, laying high-strength steel bar frames, and casting of UHPC in sections, and using epoxy resin structural glue to enhance the bonding to form a reinforced structure that is synergistically subjected to stress.
Convenient construction, significantly improved bearing capacity, enhanced durability, avoid shrinkage cracks, reduce construction costs and cycles, and is suitable for building and bridge reinforcement and renovation.
Smart Images
Figure CN120465729A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of civil engineering structure reinforcement, and particularly relates to a reinforced concrete beam reinforcement method based on segmented casting of high-strength steel bars and UHPC and the resulting reinforced structure. Background Art
[0002] Existing reinforced concrete beams (original concrete beams) often require reinforcement due to improved design standards, changes in their functional use, or degradation in durability. Traditional reinforcement methods, such as increasing the cross-section, suffer from issues such as heavy wet work, long construction periods, and a significant increase in the structure's deadweight. The fiber-bonded composite method suffers from defects such as easy interface delamination, poor high-temperature resistance, and limited improvement in bearing capacity. Furthermore, the external steel reinforcement method suffers from high costs and complex joint processing.
[0003] Ultra-high-performance concrete (UHPC), with its exceptional strength, durability, and toughness, offers significant advantages in structural reinforcement. However, UHPC's shrinkage characteristics and interoperability with existing structures remain key challenges. Furthermore, for beams with large spans or complex load conditions, pouring UHPC in one go can lead to shrinkage cracks, compromising the reinforcement effectiveness. Therefore, developing an efficient, reliable, and economical reinforced concrete beam reinforcement method is of great engineering significance. Summary of the Invention
[0004] The purpose of the present invention is to address the existing problems and provide a reinforced concrete beam reinforcement method based on segmented casting of high-strength steel bars and UHPC and the resulting reinforced structure.
[0005] The present invention is achieved through the following technical solutions: A reinforced concrete beam reinforcement method based on segmented casting of high-strength steel bars and UHPC comprises the following steps: S1. Beam pretreatment: The original concrete beam surface was cleaned and mechanically polished to roughen the surface to enhance bonding performance. Holes were drilled in the reinforced area at the bottom of the original concrete beam, high-strength anchor bars were implanted, dust was cleaned from the holes, and epoxy resin structural adhesive was injected to ensure reliable anchoring. S2. High-strength steel bar arrangement: Based on the stress calculation results of the original concrete beam, high-strength steel bars are arranged in the tension zone at the bottom of the original concrete beam. The high-strength anchor bars are connected to the original concrete beam to form a reinforced steel skeleton. The spacing and number of high-strength steel bars are determined according to the reinforcement requirements and the reinforced concrete structure design analysis. S3. UHPC pouring: According to the actual engineering design and construction needs, combined with the fluidity of UHPC, the beam reinforcement area is divided into sections, and then UHPC is poured; S4. Post-reinforcement inspection: Carry out an appearance inspection on the reinforced beam to check for defects such as cracks and honeycombs.
[0006] Furthermore, the diameter of the drill hole in step S1 is 2-4 mm larger than the diameter of the high-strength anchor bar, and the hole depth is not less than 5 times the diameter of the high-strength anchor bar, to ensure effective anchoring of the high-strength anchor bar.
[0007] Furthermore, during the segmentation described in step S3, the segment length is precisely controlled within a range of 600-1000 mm based on the fluidity of UHPC, and casting holes are reserved on both sides of each template to facilitate exhaust and material distribution during UHPC casting, thereby ensuring casting density.
[0008] Furthermore, the UHPC pouring described in step S3 is specifically as follows: first, the odd-numbered reinforcement area is wrapped with a template, and a pouring hole is reserved on both sides of each template; UHPC that meets the workability and strength requirements is prepared, and the UHPC is poured into the template through the pouring holes. After 24 hours, the template is removed, and the sides of the poured UHPC are coated with epoxy resin structural adhesive with a thickness of 0.5-1.0 mm; then, the even-numbered reinforcement area is wrapped with a template, and pouring holes are reserved on both sides of each template. The UHPC is poured and cured for 24 hours before being removed from the template.
[0009] A reinforced concrete beam reinforcement structure includes an original concrete beam. The original concrete beam surface is treated and then reinforced with a reinforcement bar system formed of high-strength steel bars. The high-strength steel bars are reliably connected to the original concrete beam through high-strength anchor bars. UHPC segments wrap the high-strength steel bars and bond to the original concrete beam surface to form an overall reinforcement system that is subjected to coordinated force.
[0010] Furthermore, the high-strength steel bars include main bars and high-strength anchor bars in the tensile zone at the bottom of the beam. The main bars are made of HRB600 and above strength grade steel bars, and the high-strength anchor bars are made of HRB500 and above strength grade steel bars to meet the reinforcement and anchoring requirements.
[0011] Furthermore, the anchoring structure is a high-strength anchor bar implanted in the original concrete beam. The high-strength anchor bar is bonded and fixed to the original concrete beam by epoxy resin structural adhesive. The diameter of the high-strength anchor bar is 8~16 mm, which ensures the anchoring strength and stability.
[0012] Compared with the prior art, the present invention has the following advantages: This invention addresses the need to reinforce existing reinforced concrete beams. It constructs a reinforced structure through a complete process of pre-treatment of the original concrete beam (surface cleaning, drilling and planting reinforcement bars) - high-strength steel bar reinforcement (forming a reinforced reinforcement bar system) - segmented UHPC casting (including interfacial epoxy resin structural adhesive for enhanced bonding) - and maintenance and inspection. This invention leverages the high strength and durability of UHPC and the mechanical advantages of high-strength steel bars to synergistically improve the load-bearing capacity and ductility of existing beams, resolving issues such as the complexity of traditional reinforcement construction and insufficient durability. Compared to traditional methods, this method offers convenient construction and significantly improved load-bearing capacity. It is suitable for reinforcement and renovation scenarios such as buildings and bridges, providing an effective solution for the safe and longevity of existing structures and promoting the upgrading of reinforcement technology.
[0013] (1) Construction convenience: Segmented casting of UHPC effectively reduces the length of a single casting, reduces shrinkage stress, and avoids cracks. At the same time, the reserved casting hole design facilitates construction operations and improves casting quality and efficiency.
[0014] (2) Synergistic working performance: The synergistic effect of high-strength steel bars and UHPC significantly improves the bending and shear bearing capacity of the beam; the use of epoxy resin structural adhesive enhances the bonding performance between new and old materials, ensuring the overall load-bearing performance.
[0015] (3) Improvement: The high density and impermeability of UHPC effectively resist erosion from the external environment and extend the service life of the structure; the corrosion resistance of high-strength steel bars further ensures the long-term performance stability of the reinforced structure.
[0016] (4) Economical: Compared with traditional reinforcement methods, the present invention reduces the amount of wet work and construction period, thus reducing the overall cost; at the same time, the improvement of structural performance reduces the subsequent maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 is a flow chart of the reinforcement method of the present invention; Figure 2 A schematic diagram of a reinforced concrete beam reinforcement structure according to the present invention; Figure 3 A schematic diagram of the arrangement of high-strength steel bars according to the present invention; Figure 4 Schematic diagram of the segmented casting of odd-numbered sections of UHPC according to the present invention; Figure 5 Schematic diagram of the segmented casting of even-numbered sections of UHPC according to the present invention; Figure 6 is a schematic cross-sectional view of the reinforcement structure of the present invention; In the figure: 1. Original concrete beam; 2. High-strength anchor bars; 3. UHPC; 4. High-strength longitudinal bars; 5. Odd-numbered UHPC sections; 6. Epoxy resin structural adhesive; 7. Even-numbered UHPC sections. DETAILED DESCRIPTION
[0018] In order to further explain the present invention, it is described below with reference to the following specific embodiments.
[0019] Example 1: A reinforced concrete beam reinforcement method based on segmented casting of high-strength steel bars and UHPC, comprising the following steps: S1. Determination of the number of segments: Based on the test results and load requirements, determine the cross-sectional area of the high-strength longitudinal reinforcement 4 and the number of high-strength anchor bars 2, and determine the properties of the UHPC material to be used; determine the number of segments in the beam reinforcement area based on the length of the original concrete beam 1 and the properties of the UHPC material; S2. Beam pretreatment: Use an electric grinder to thoroughly remove the paint layer, loose concrete, and oil stains on the surface of the original concrete beam 1. After grinding, the surface roughness reaches 6 mm. Cracks with a width greater than 0.2 mm are repaired using pressure-injected epoxy resin structural adhesive 6. Cracks with a width less than 0.2 mm are sealed using epoxy resin structural adhesive 6. S3, drilling and planting reinforcement: Drill holes at the bottom of the original concrete beam 1 at the designed position. The hole diameter is 3 mm larger than the diameter of the high-strength anchor bar 2 and the hole depth is 5 times the diameter of the high-strength anchor bar 2. Use an industrial vacuum cleaner to clean the dust in the hole, inject Class A anchor glue, and implant the high-strength anchor bar 2. Let it stand and cure for 48 hours without disturbance. S3, interface enhancement: Spray a layer of epoxy resin structural adhesive 6 on the surface of the original concrete beam 1 to form a rough bonding layer to enhance the bonding performance with UHPC3; S4. High-strength steel bar installation: Rebar processing: Cut and bend high-strength steel bars according to the designed dimensions to ensure that the ends of the steel bars are straight and the bending angle and curvature meet the requirements of the specifications; Rebar fixing: Connect the processed high-strength steel bars to the original concrete beam 1 through high-strength anchor bars 2, and fix them by combining binding and welding to ensure that the position of the steel skeleton is accurate and firm; S5. Template production and installation: Customize detachable steel formwork, ensure the inner surface of the formwork is smooth and apply release agent, ensure the formwork joints are tight to prevent slurry leakage, install the odd-numbered formwork sections first, reserve a 60 mm diameter casting hole on both sides of each formwork section, and fix the formwork with bolts and support systems to ensure the formwork is firm and accurately positioned; S6. UHPC3 preparation and pouring: Mix UHPC3 according to the mix ratio at a professional mixing station, using a forced mixer to ensure uniformity of the mixture; The mixed UHPC3 was transported to the pouring site by a small concrete pump truck and slowly injected from the reserved pouring holes. Its self-compacting property was used to fill the formwork to avoid vibration damaging the steel fiber distribution. 24 hours after the odd-numbered sections were poured, the formwork was removed, the sides of the UHPC3 were roughened, cleaned, and then coated with epoxy resin structural adhesive 6. Then the even-numbered sections of the formwork were installed and the UHPC3 was poured. S7, curing and demoulding: After pouring odd-numbered UHPC5 and even-numbered UHPC7 sections, immediately cover them with plastic film and add insulation blankets. Use watering to maintain a moist surface for at least 14 days. After pouring UHPC3 for 24 hours, carefully remove the formwork to avoid damaging the reinforcement layer. S8. Inspection and acceptance: After reinforcement, the surface of the beam is smooth, without defects such as cracks, honeycombs, and pitting, and the segmented joints are tightly connected.
[0020] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.
Claims
1. A reinforced concrete beam reinforcement method based on segmented casting of high-strength steel bars and UHPC, characterized in that: The steps include: S1. Beam pretreatment: The original concrete beam surface was cleaned and mechanically polished to make it rough. Holes were drilled in the bottom reinforcement area of the original concrete beam, high-strength anchor bars were implanted, dust in the holes was cleaned, and epoxy resin structural adhesive was injected. S2. High-strength steel bar arrangement: Based on the stress calculation results of the original concrete beam, high-strength steel bars are arranged in the tension zone at the bottom of the original concrete beam. The high-strength anchor bars are connected to the original concrete beam to form a reinforced steel skeleton. The spacing and number of high-strength steel bars are determined according to the reinforcement requirements and the reinforced concrete structure design analysis. S3. UHPC pouring: According to the actual engineering design and construction needs, combined with the fluidity of UHPC, the beam reinforcement area is divided into sections, and then UHPC is poured; S4. Post-reinforcement inspection: Carry out an appearance inspection on the reinforced beam to check for defects such as cracks and honeycombs.
2. The reinforced concrete beam reinforcement method based on segmented casting of high-strength steel bars and UHPC according to claim 1, characterized in that: The diameter of the drill hole in step S1 is 2 to 4 mm larger than the diameter of the high-strength anchor bar, and the hole depth is not less than 5 times the diameter of the high-strength anchor bar.
3. The reinforced concrete beam reinforcement method based on segmented casting of high-strength steel bars and UHPC according to claim 1, characterized in that: During the segmentation described in step S3, the segment length is precisely controlled within a range of 600-1000 mm according to the fluidity of UHPC, and casting holes are reserved on both sides of each template.
4. The reinforced concrete beam reinforcement method based on segmented casting of high-strength steel bars and UHPC according to claim 1, characterized in that: The UHPC pouring described in step S3 is specifically as follows: first, the odd-numbered reinforcement area is wrapped with a template, and a pouring hole is reserved on both sides of each template segment; UHPC that meets the workability and strength requirements is prepared, and the UHPC is poured into the template through the pouring holes. After 24 hours, the template is removed, and the sides of the poured UHPC are coated with epoxy resin structural adhesive with a thickness of 0.5-1.0 mm; then, the even-numbered reinforcement area is wrapped with a template, and pouring holes are reserved on both sides of each template segment. The UHPC is poured and cured for 24 hours before being removed from the template.
5. A reinforced concrete beam reinforcement structure formed by the method according to any one of claims 1 to 4, characterized in that: It includes the original concrete beam. After the surface of the original concrete beam is treated, a reinforcement system formed by high-strength steel bars is arranged. The high-strength steel bars are reliably connected to the original concrete beam through an anchoring structure. UHPC segments wrap the high-strength steel bars and bond to the surface of the original concrete beam to form an overall reinforcement system with coordinated force.
6. The reinforced concrete beam reinforcement structure according to claim 5, characterized in that: The high-strength steel bars include main bars and high-strength anchor bars in the tension zone at the bottom of the original concrete beam. The main bars are made of HRB600 and above strength grade steel bars, and the high-strength anchor bars are made of HRB500 and above strength grade steel bars.
7. The reinforced concrete beam reinforcement structure according to claim 5, characterized in that: The anchoring structure is a high-strength anchor bar embedded in the original concrete beam. The high-strength anchor bar is fixed to the original concrete beam by epoxy resin structural adhesive. The diameter of the high-strength anchor bar is 8-16 mm.