Method for improving engineering quality of bridge expansion joint

Abstract

The present application relates to a method for improving the engineering quality of bridge expansion joints, belonging to the technical field of bridge reinforcement. The method is based on the function gradient theory, and by pouring super-high toughness filling layer and super-high strength filling layer on the upper surface of the bridge expansion joint transition zone slab in turn, and setting the thickness ratio of the super-high toughness filling layer and the super-high strength filling layer as 0.3-0.7, the composite structure of super-high strength cement-based material and super-high toughness cement-based material is realized. The super-high strength filling layer material and the super-high toughness filling layer material are both functional materials with excellent mechanical properties and durability. The formed function gradient structure form jointly bears the main role, has better integrity, improves the wear resistance and corrosion resistance of the transition zone concrete surface layer, relieves the pressure of the diseases such as net cracking, fracture and spalling of the traditional filling material during service, improves the driving comfort, reduces the maintenance and operation cost of the bridge expansion joint, and ensures the service performance.

Description

Technical Field

[0001] This invention relates to a method for improving the quality of bridge expansion joint engineering, belonging to the field of bridge reinforcement technology. Background Technology

[0002] Bridge expansion joints are auxiliary structures installed between bridge abutments and beam ends, and between adjacent bridge spans. Their main function is to prevent structural damage or failure of the bridge main body caused by factors such as load, temperature difference, and its own shrinkage. They also guide and buffer the overall displacement of the bridge, preventing damage from massive impacts caused by unpredictable forces such as earthquakes. The rapid increase in traffic volume and the ever-increasing weight of vehicles have led to many bridges, before reaching their designed service life, prematurely entering the repair stage due to defects such as wear, erosion, cracking, fracture, spalling, and debonding of the concrete in the transition zone of the expansion joints from the main structure and asphalt pavement. Therefore, the quality control of the concrete in the transition zone has a significant impact on the structural performance of bridge expansion joints, driving safety, and comfort, and is a key aspect of road and bridge maintenance and operation. Currently, steel fiber reinforced concrete, micro-expansion high-strength concrete, or polymer repair mortar are mainly used to treat concrete defects in the transition zone of bridge expansion joints. However, due to their rigidity or flexibility, single filling systems cannot completely cure the defects and are difficult to achieve the expected results. Defects such as wear, erosion, cracking, fracture, and spalling of the concrete in the transition zone continue to occur, increasing the pressure on later operation.

[0003] Patent CN106894332B discloses a repair structure and construction method for the transition zone of expansion joints in highway concrete bridges. The repair structure designed by the method consists of a high-performance wear-resistant overlay layer and an ultra-high toughness self-compacting concrete layer. The high-performance wear-resistant overlay layer is laid on top of the ultra-high toughness self-compacting concrete layer, which is equipped with a prestressed steel hinged truss. However, the repair structure has certain defects in terms of materials and structure: On the one hand, the high-performance wear-resistant overlay layer is cast with cement asphalt mortar, which can improve the wear and tear of the concrete in the transition zone of the bridge expansion joint to a certain extent. However, the cement asphalt mortar has relatively poor durability and is prone to aging, affecting the long-term service performance of the material. On the other hand, the C80 ultra-high toughness self-compacting concrete used in the ultra-high toughness self-compacting concrete layer still has relatively strong rigidity, and the risk of fracture of the lower structure in the transition zone is still relatively high during the load-bearing process. On the other hand, in the method, the high-performance wear-resistant overlay layer mainly plays a wear-resistant role in the entire bridge expansion joint transition zone and does not serve as the main structure. The structural layer is relatively thin and only bears the load transfer function, so its mechanical strength is relatively poor. Therefore, there is an urgent need to further develop methods to improve the quality of bridge expansion joint engineering. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, the present invention aims to provide a method for improving the quality of bridge expansion joint engineering. The method is based on the functional gradient theory to realize a composite structure of ultra-high strength cement-based materials and ultra-high toughness cement-based materials, which combines rigidity and flexibility. This not only improves the wear resistance and erosion resistance of the concrete surface layer in the transition zone, but also alleviates the pressure of traditional filling materials experiencing network cracking, breakage and spalling during service, improves driving comfort, reduces the maintenance and operation costs of bridge expansion joints, and ensures service performance.

[0005] The objective of this invention is achieved through the following technical solution.

[0006] A method for improving the quality of bridge expansion joint engineering, the method comprising the following steps:

[0007] (1) Remove the original filling material in the reserved groove of the bridge expansion joint transition area to expose the beam and the inner wall of the reserved groove. Roughen the upper surface of the beam to obtain a rough surface with concave and convex dots. Spray a layer of concrete interface adhesive on the rough surface and the inner wall of the reserved groove.

[0008] (2) Pour ultra-high toughness cement-based material into the reserved groove of the bridge expansion joint transition area where concrete interface adhesive was sprayed in step (1), and roughen, sawtooth interface or pre-embed shear reinforcement on the upper surface of the ultra-high toughness cement-based material blank during the pouring process, and form an ultra-high toughness filling layer after complete curing.

[0009] The components and their weight percentages of the ultra-high toughness cement-based material are as follows: 550-750 parts cement, 500-700 parts type I high-activity admixture, 600-800 parts quartz powder, 12-16 parts polyvinyl alcohol (PVA) fiber, 2-3 parts water-reducing agent, 40-70 parts expansion agent, and 400-550 parts water.

[0010] The components and their weight percentages of the Type I high-activity admixture are as follows: 50-70 parts silica fume, 20-80 parts vitrified microspheres, and 430-550 parts Grade I fly ash.

[0011] (3) Spray another layer of concrete interface adhesive onto the surface of the ultra-high toughness filler layer obtained in step (2), and pour ultra-high strength cement-based material. After complete curing, an ultra-high strength filler layer is formed.

[0012] The components and their weight percentages of the ultra-high strength cement-based material are as follows: 800-900 parts of cement, 180-230 parts of type II high-activity admixture, 900-1100 parts of quartz sand, 120-160 parts of steel fiber, 7-10 parts of water-reducing agent, 2-5 parts of defoamer, and 150-190 parts of water.

[0013] The Type II high-activity admixture consists of the following components and their weight percentages: 40-60 parts silica fume, 20-30 parts vitrified microspheres, and 120-140 parts ultrafine mineral powder.

[0014] The thickness ratio of the ultra-high toughness filler layer to the ultra-high strength filler layer is 0.3 to 0.7;

[0015] (4) After pouring, perform standard curing for 28 days at room temperature of 25℃.

[0016] Preferably, the ultra-high strength filling layer, the ultra-high toughness filling layer, and the beam slab are provided with anchor bars laid in a grid pattern to reinforce the bridge expansion joint transition zone as a whole.

[0017] Preferably, the concrete interface adhesive is an acrylic epoxy resin water-based emulsion; the acrylic epoxy resin water-based emulsion is milky white, odorless, and has good anti-corrosion properties, which can significantly improve the mutual adhesion between the interface of the beam and slab and the ultra-high strength filling layer, and between the ultra-high strength filling layer and the ultra-high toughness filling layer.

[0018] Preferably, the cement is silicate cement or ordinary silicate cement with a strength grade of not less than 42.5.

[0019] Preferably, the quartz powder has a continuous gradation with a particle size of 0.106–0.075 mm and a SiO2 content greater than 97%.

[0020] Preferably, the PVA fiber is a high-strength, high-modulus polyvinyl alcohol fiber with a tensile strength greater than 1600 MPa and an elastic modulus greater than 40 GPa, with a diameter of 0.02–0.04 mm and a length of 5–12 mm.

[0021] Preferably, the water-reducing agent is a polycarboxylate-modified ether powder water-reducing agent with a water reduction rate greater than 25%.

[0022] Preferably, the expansive agent is a high-performance concrete expansive agent with dual expansion sources, exhibiting a 7-day restricted expansion rate in water greater than 0.05%, a 1-day compressive strength ratio greater than 120%, and a 28-day compressive strength ratio greater than 100%.

[0023] Preferably, the quartz sand is a continuous grade of three particle sizes: 1.25–0.63 mm, 0.63–0.315 mm, and 0.315–0.165 mm, and has a SiO2 content greater than 97%.

[0024] Preferably, the steel fiber is a high-strength micro-fine steel fiber with a tensile strength greater than 2850MPa, a round cross-section, straight ends, and copper plating, with a diameter of 0.18-0.22mm and a length of 12-14mm.

[0025] Preferably, the defoamer is a polyether-modified silicone defoamer. The molecular structure of polyether-modified silicone defoamers contains short-chain polysiloxane hydrophobic groups and polyether hydrophilic groups, which have excellent water solubility and surface activity, are alkali and acid resistant, have high defoaming rate and long foam suppression time.

[0026] Beneficial effects

[0027] (1) This invention provides a method for improving the quality of bridge expansion joint engineering. The method involves sequentially pouring an ultra-high toughness filling layer and an ultra-high strength filling layer onto the upper surface of the beam slab in the transition zone of the bridge expansion joint. The thickness ratio of the ultra-high toughness filling layer to the ultra-high strength filling layer is set to 0.3 to 0.7 to achieve a composite structure of ultra-high strength cement-based material and ultra-high toughness cement-based material. Both the ultra-high strength filling layer material and the ultra-high toughness filling layer material are functional materials with excellent mechanical properties and durability. Through the formation of a functional gradient (the bottom layer increases toughness function - the surface layer increases strength function), they jointly undertake the main function, resulting in better overall integrity. This not only improves the wear resistance and erosion resistance of the concrete surface layer in the transition zone, but also alleviates the pressure of traditional filling materials experiencing network cracking, breakage, and spalling during service, improves driving comfort, reduces the maintenance and operation costs of bridge expansion joints, and ensures service performance.

[0028] (2) This invention provides a method for improving the quality of bridge expansion joint engineering. The method involves roughening the surface of the beam to increase the roughness of the contact surface and improve the interface strength between the beam and the ultra-high toughness filling layer. Then, by roughening, serrifying the interface, or pre-embedding shear bars during the pouring process of the ultra-high toughness filling layer, the integrity of the functional gradient material of the ultra-high strength filling layer and the ultra-high toughness filling layer is strengthened. In addition, the method also sprays concrete interface adhesive between the contact surfaces of different structural materials. This solves the problem of debonding and separation between traditional filling materials and the main structure and asphalt pavement, ensuring that the reserved groove concrete and the ultra-high strength filling layer and the ultra-high toughness filling layer work together to bear the force, greatly improving the wear resistance and erosion resistance of the upper structure of the transition zone, and ensuring the design service life of the concrete in the transition zone of the bridge expansion joint.

[0029] (3) This invention provides a method for improving the quality of bridge expansion joint engineering. The method involves filling the surface layer structure of the bridge expansion joint transition zone with ultra-high strength cement-based material. This ultra-high strength cement-based material is based on the principle of closest packing, with optimized gradation and a scientifically designed mix ratio. Furthermore, by controlling the type II high-activity admixtures and additives of the ultra-high strength cement-based material, the material exhibits advantages such as high strength, excellent durability, and resistance to aging. It also overcomes the shortcomings of conventional ultra-high strength cement-based materials and ultra-high toughness cement-based materials, which require high-temperature steam curing (80–200℃) and stringent process requirements. This method achieves ultra-high strength cement-based materials with a compressive strength greater than 140 MPa and a fracture toughness greater than 20 kJ / m² after 28 days of standard curing at room temperature on-site. 2 The ultra-high toughness cement-based material meets the application index requirements for improving the quality of bridge expansion joint projects.

[0030] (4) The present invention provides a method for improving the quality of bridge expansion joint engineering. The method uses ultra-high toughness cement-based material to fill the bottom structure of the transition zone of the bridge expansion joint. The ultra-high toughness cement-based material is based on the principle of the closest packing, with optimized gradation and scientifically designed mix ratio. Furthermore, by controlling the type I high-activity admixture and additives of the ultra-high toughness cement-based material, the ultra-high toughness cement-based material has strain hardening characteristics, excellent bending strength and bending toughness, and significantly reduces the risk of the lower structure of the transition zone cracking due to the positive bending moment. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the bridge expansion joint transition zone described in Example 1;

[0032] Figure 2 This is an enlarged schematic diagram of the interface between the ultra-high strength filling layer and the ultra-high toughness filling layer in the schematic diagram of the bridge expansion joint transition zone described in Example 1;

[0033] Figure 3 This is an enlarged schematic diagram of the interface between the ultra-high strength filling layer and the ultra-high toughness filling layer in the schematic diagram of the bridge expansion joint transition zone described in Example 2;

[0034] Figure 4 This is an enlarged schematic diagram of the interface between the ultra-high strength filling layer and the ultra-high toughness filling layer in the schematic diagram of the bridge expansion joint transition zone described in Example 3;

[0035] Among them, 1-bridge deck pavement layer, 2-anchor bar, 3-expansion joint, 4-beam and slab, 5-ultra-high strength filling layer, 6-ultra-high toughness filling layer, 7-roughened interface, 8-serrated interface, 9-shear bar interface. Detailed Implementation

[0036] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. Unless otherwise specified, the methods described are conventional methods, and the raw materials described are available from publicly available commercial sources.

[0037] Raw material information:

[0038] Concrete interface adhesive: PS608 acrylic epoxy resin waterborne emulsion manufactured by BASF Europe.

[0039] Water-reducing agent: PC-1030 polycarboxylate modified ether powder water-reducing agent produced by Suzhou Xingbang Chemical Building Materials Co., Ltd., with a water reduction rate of more than 25%;

[0040] Defoamer: P803 polyether-modified silicone defoamer manufactured by Minling Chemicals, Germany;

[0041] Expansion agent: HCSA-II dual expansion source high-performance concrete expansion agent produced by Tianjin Baoming Co., Ltd. The expansion agent has a 7-day restricted expansion rate in water greater than 0.05%, a 1-day compressive strength ratio greater than 120%, and a 28-day compressive strength ratio greater than 100%.

[0042] Quartz sand: three continuous gradations with particle sizes of 1.25–0.63 mm, 0.63–0.315 mm and 0.315–0.165 mm, and SiO2 content greater than 97%.

[0043] Quartz powder: continuously graded with a particle size of 0.106-0.075 mm and a SiO2 content greater than 97%.

[0044] The steel fiber is a high-strength micro-fine steel fiber with a tensile strength greater than 2850MPa, a round cross-section, straight ends, and copper plating, with a diameter of 0.18-0.22mm and a length of 12-14mm.

[0045] PVA fiber: High-strength, high-modulus polyvinyl alcohol fiber with a tensile strength greater than 1600MPa and an elastic modulus greater than 40GPa, with a diameter of 0.02-0.04mm and a length of 5-12mm.

[0046] Example 1

[0047] A method for improving the quality of bridge expansion joint engineering, the method comprising the following steps:

[0048] (1) Remove the original filling material of the reserved groove under the bridge deck pavement layer 1 in the bridge expansion joint transition area to expose the beam 4 and the inner wall of the reserved groove. Roughen the upper surface of the beam 4 to obtain a rough surface with concave and convex dots. Spray a layer of concrete interface adhesive on the rough surface and the inner wall of the reserved groove.

[0049] (2) Lay anchor bars in a grid pattern to reinforce the bridge expansion joint transition area as a whole. Pour ultra-high toughness cement-based material into the reserved groove of the bridge expansion joint transition area where concrete interface adhesive was sprayed in step (1). During the pouring process, roughen the upper surface of the ultra-high toughness cement-based material blank. After complete curing, an ultra-high toughness filling layer 6 is formed.

[0050] The components and their weight percentages of the ultra-high toughness cement-based material are as follows: 550 parts of silicate cement with a strength grade of not less than 42.5, 500 parts of type I high-activity admixture, 600 parts of quartz powder, 12 parts of PVA fiber, 2 parts of water-reducing agent, 40 parts of expansion agent, and 400 parts of water.

[0051] The components and their weight percentages of the Type I high-activity admixture are as follows: 50 parts silica fume, 20 parts vitrified microspheres, and 430 parts Grade I fly ash.

[0052] (3) A layer of concrete interface adhesive is sprayed onto the upper surface of the ultra-high toughness filler layer 6 obtained in step (2), and ultra-high strength cement-based material is poured in. After complete curing, an ultra-high strength filler layer 5 is formed, and a roughened interface 7 is formed between the upper surface of the ultra-high toughness filler layer 6 and the lower surface of the ultra-high strength filler layer 5 (e.g., Figure 2 (as shown);

[0053] The components and their weight percentages of the ultra-high strength cement-based material are as follows: 800 parts of silicate cement with a strength grade of not less than 42.5, 180 parts of type II high-activity admixture, 900 parts of quartz sand, 120 parts of steel fiber, 7 parts of water-reducing agent, 2 parts of defoamer, and 150 parts of water.

[0054] The components and their weight percentages of the Type II high-activity admixture are as follows: 40 parts silica fume, 20 parts vitrified microspheres, and 120 parts ultrafine mineral powder.

[0055] The thickness ratio of the ultra-high toughness filler layer 6 to the ultra-high strength filler layer 5 is 0.3;

[0056] (4) After pouring, standard curing is carried out for 28 days at room temperature (25℃) to obtain the bridge expansion joint transition area (e.g., after improving the project quality) Figure 1 (As shown).

[0057] Example 2

[0058] A method for improving the quality of bridge expansion joint engineering, the method comprising the following steps:

[0059] (1) Remove the original filling material of the reserved groove under the bridge deck pavement layer 1 in the bridge expansion joint transition area to expose the beam 4 and the inner wall of the reserved groove. Roughen the upper surface of the beam 4 to obtain a rough surface with concave and convex dots. Spray a layer of concrete interface adhesive on the rough surface and the inner wall of the reserved groove.

[0060] (2) Lay anchor bars in a grid pattern, pour ultra-high toughness cement-based material into the reserved groove of the bridge expansion joint transition area where concrete interface adhesive was sprayed in step (1), and serrate the upper surface of the ultra-high toughness cement-based material blank during the pouring process. After complete curing, an ultra-high toughness filling layer 6 is formed.

[0061] The components and their weight percentages of the ultra-high toughness cement-based material are as follows: 750 parts of ordinary silicate cement, 700 parts of type I high-activity admixture, 800 parts of quartz powder, 16 parts of PVA fiber, 3 parts of water-reducing agent, 70 parts of expansion agent, and 550 parts of water.

[0062] The components and their weight proportions of the Type I high-activity admixture are as follows:

[0063] 70 parts silica fume, 80 parts vitrified microspheres, and 550 parts Class I fly ash;

[0064] (3) A layer of concrete interface adhesive is sprayed onto the upper surface of the ultra-high toughness filler layer 6 obtained in step (2), and ultra-high strength cement-based material is poured in. After complete curing, an ultra-high strength filler layer 5 is formed, and a serrated interface 8 is formed between the upper surface of the ultra-high toughness filler layer 6 and the lower surface of the ultra-high strength filler layer 5 (e.g., Figure 3 (as shown);

[0065] The components and their weight percentages of the ultra-high strength cement-based material are as follows: 900 parts of ordinary silicate cement, 230 parts of type II high-activity admixture, 1100 parts of quartz sand, 160 parts of steel fiber, 10 parts of water-reducing agent, 5 parts of defoamer, and 190 parts of water.

[0066] The components and their weight percentages of the Type II high-activity admixture are as follows: 60 parts silica fume, 30 parts vitrified microspheres, and 140 parts ultrafine mineral powder.

[0067] The thickness ratio of the ultra-high toughness filler layer 6 to the ultra-high strength filler layer 5 is 0.5;

[0068] (4) After the pouring is completed, the bridge expansion joint transition area is cured for 28 days at room temperature of 25℃ to improve the quality of the project.

[0069] Example 3

[0070] A method for improving the quality of bridge expansion joint engineering, the method comprising the following steps:

[0071] (1) Remove the original filling material of the reserved groove under the bridge deck pavement layer 1 in the bridge expansion joint transition area to expose the beam 4 and the inner wall of the reserved groove. Roughen the upper surface of the beam 4 to obtain a rough surface with concave and convex dots. Spray a layer of concrete interface adhesive on the rough surface and the inner wall of the reserved groove.

[0072] (2) Lay anchor bars in a grid pattern, pour ultra-high toughness cement-based material into the reserved groove of the bridge expansion joint transition area where concrete interface adhesive was sprayed in step (1), and treat the upper surface of the ultra-high toughness cement-based material blank with shear bars during the pouring process. After complete curing, an ultra-high toughness filling layer 6 is formed.

[0073] The components and their weight percentages of the ultra-high toughness cement-based material are as follows: 650 parts of silicate cement with a strength grade of not less than 42.5, 600 parts of type I high-activity admixture, 700 parts of quartz powder, 14 parts of PVA fiber, 2.5 parts of water-reducing agent, 55 parts of expansion agent, and 475 parts of water.

[0074] The components and their weight percentages of the Type I high-activity admixture are as follows: 60 parts silica fume, 50 parts vitrified microspheres, and 490 parts Grade I fly ash.

[0075] (3) A layer of concrete interface adhesive is sprayed onto the upper surface of the ultra-high toughness filler layer 6 obtained in step (2), and ultra-high strength cement-based material is poured in. After complete curing, an ultra-high strength filler layer 5 is formed. A shear reinforcement interface 8 is formed between the upper surface of the ultra-high toughness filler layer 6 and the lower surface of the ultra-high strength filler layer 5 (e.g., Figure 4 (as shown);

[0076] The components and their weight percentages of the ultra-high strength cement-based material are as follows: 850 parts of silicate cement with a strength grade of not less than 42.5, 205 parts of type II high-activity admixture, 1000 parts of quartz sand, 140 parts of steel fiber, 8.5 parts of water-reducing agent, 2.5 parts of defoamer, and 170 parts of water.

[0077] The components and their weight percentages of the Type II high-activity admixture are as follows: 50 parts silica fume, 25 parts vitrified microspheres, and 130 parts ultrafine mineral powder.

[0078] The thickness ratio of the ultra-high toughness filler layer 6 to the ultra-high strength filler layer 5 is 0.7;

[0079] (4) After the pouring is completed, the bridge expansion joint transition area is cured for 28 days at room temperature of 25℃ to improve the quality of the project.

[0080] According to T~CBMF 37~2018 "Basic Properties and Test Methods of Ultra-High Performance Concrete", the strength of the ultra-high strength filling layer prepared in Examples 1 to 3 was tested, and the results are shown in Table 1. "—" indicates that this test was not performed.

[0081] According to DBJ 61 / T 112~2021 "Technical Specification for Application of High Ductility Concrete", the toughness of the ultra-high toughness filling layer prepared in Examples 1 to 3 was tested, and the results are shown in Table 1.

[0082] According to JGJ / T 70~2009 "Standard for Test Methods of Basic Performance of Building Mortar", the tensile bond strength of the transition zone of the bridge expansion joint described in Examples 1 to 3 was tested, and the results are shown in Table 1.

[0083] Table 1 Performance tests of the ultra-high strength and ultra-high toughness filler layers prepared in Examples 1-3

[0084]

[0085] As can be seen from Table 1, the super-tough filling layer-super-strong filling layer main structure designed based on the functional gradient theory of the present invention has strong overall bonding force and firm interface bonding between each layer, exhibiting excellent mechanical properties. Furthermore, all performance tests were conducted at room temperature for 28 days of curing, and all performance indicators met the standard requirements. This indicates that the bridge expansion joint transition zone in the method of the present invention does not require steam curing and can be cured at room temperature. The method of the present invention can significantly improve the engineering quality of bridge expansion joints.

[0086] The above detailed description further illustrates the purpose, technical solution, and beneficial effects of the invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for improving the quality of bridge expansion joint engineering, characterized in that: The method steps are as follows: (1) Remove the original filling material in the reserved groove of the bridge expansion joint transition area to expose the beam and the inner wall of the reserved groove. Roughen the upper surface of the beam to obtain a rough surface with concave and convex dots. Spray a layer of concrete interface adhesive on the rough surface and the inner wall of the reserved groove. (2) Pour ultra-high toughness cement-based material into the reserved groove in the transition area of ​​the bridge expansion joint, and roughen, sawtooth the interface or pre-embed shear reinforcement on the upper surface of the ultra-high toughness cement-based material blank during the pouring process. After complete curing, an ultra-high toughness filling layer is formed. (3) Spray another layer of concrete interface adhesive onto the surface of the ultra-high toughness filler layer, and pour ultra-high strength cement-based material. After complete curing, an ultra-high strength filler layer is formed. The thickness ratio of the ultra-high toughness filler layer to the ultra-high strength filler layer is 0.3~0.7; (4) After pouring, perform standard curing for 28 days at room temperature (25℃); The components and their weight percentages of the ultra-high toughness cement-based material are as follows: 550-750 parts cement, 500-700 parts type I high-activity admixture, 600-800 parts quartz powder, 12-16 parts polyvinyl alcohol (PVA) fiber, 2-3 parts water-reducing agent, 40-70 parts expansion agent, and 400-550 parts water. The components and their weight percentages of the Type I high-activity admixture are as follows: 50-70 parts silica fume, 20-80 parts vitrified microspheres, and 430-550 parts Grade I fly ash. The components and their weight percentages of the ultra-high strength cement-based material are as follows: cement 800-900 parts, type II high-activity admixture 180-230 parts, quartz sand 900-1100 parts, steel fiber 120-160 parts, water-reducing agent 7-10 parts, defoamer 2-5 parts, and water 150-190 parts; wherein, the components and their weight percentages of the type II high-activity admixture are as follows: silica fume 40-60 parts, vitrified microspheres 20-30 parts, and ultrafine mineral powder 120-140 parts.

2. The method for improving the quality of bridge expansion joint engineering according to claim 1, characterized in that: The cement is silicate cement or ordinary silicate cement with a strength grade of not less than 42.5; the water-reducing agent is a polycarboxylate-modified ether powder water-reducing agent with a water reduction rate of more than 25%; and the concrete interface binder is an acrylic epoxy resin water-based emulsion.

3. The method for improving the quality of bridge expansion joint engineering according to claim 2, characterized in that: The quartz powder has a continuous gradation with a particle size of 0.106~0.075mm and a SiO2 content greater than 97%; the PVA fiber is a high-strength, high-modulus polyvinyl alcohol fiber with a tensile strength greater than 1600MPa and an elastic modulus greater than 40GPa, with a diameter of 0.02~0.04mm and a length of 5~12mm; the expansive agent is a high-performance concrete expansive agent with dual expansion sources, exhibiting a 7-day restricted expansion rate in water greater than 0.05%, a 1-day compressive strength ratio greater than 120%, and a 28-day compressive strength ratio greater than 100%.

4. The method for improving the quality of bridge expansion joint engineering according to claim 2, characterized in that: The quartz sand is a continuous grade of three particles with particle sizes of 1.25~0.63mm, 0.63~0.315mm and 0.315~0.165mm, respectively, and has a SiO2 content greater than 97%; the steel fiber is a high-strength micro-fine steel fiber with a tensile strength greater than 2850MPa, a round cross-section, straight ends, and copper plating, with a diameter of 0.18~0.22mm and a length of 12~14mm; the defoamer is a polyether-modified organosilicon defoamer.

5. A method for improving the quality of bridge expansion joint engineering according to any one of claims 1 to 4, characterized in that: The ultra-high strength filling layer, ultra-high toughness filling layer, and beam slab are equipped with anchor bars laid in a grid pattern to comprehensively reinforce the transition zone of the bridge expansion joint.

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