A hierarchical progressive self-locking trc prefabricated slab reinforced beam and end constraint method
Patent Information
- Application Number
- CN202611309389.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-27
- Publication Date
- 2026-09-25
AI Technical Summary
[0008]针对现有预制TRC板加固技术中纤维网端部缺少有效锚固、粘结层性能不足以及缺少有效端部约束构造等问题，本发明提供了一种分级递进式自锁TRC预制板加固梁及端部约束方法，实现了纤维网端部的可靠自锁锚固、界面粘结性能的提升以及端部剥离的有效约束，从而显著提高加固梁的整体承载力和延性
本发明中预制TRC板基体材料的优势之处在于利用了SMA纤维的超弹性和裂缝自闭合能力，可在荷载卸载后自主减小裂缝宽度，赋予基体自我修复功能，玄武岩纤维发挥增强和约束裂缝扩展作用。二者协同作用，在提升混凝土抗压强度、抗折强度和断裂韧度的同时，赋予基体裂缝自修复能力，有效提高混凝土梁体的承载能力、延性和长期耐久性能；
Smart Images
Figure CN122812469A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of building structure reinforcement technology, specifically a graded progressive self-locking TRC precast slab reinforcement beam and end constraint method. Background Technology
[0002] With the increasing service life of existing building structures and the raising of load standards, a large number of reinforced concrete beams require reinforcement. In recent years, precast TRC (Textile Reinforced Concrete) slab reinforcement has been increasingly used for reinforcing reinforced concrete beam members due to its advantages such as high strength, corrosion resistance, and ease of construction. Precast TRC slabs are manufactured in a factory and then bonded on-site, effectively reducing on-site wet work, offering excellent construction convenience, and significantly improving the load-bearing capacity of reinforced concrete beams.
[0003] However, the precast TRC slab reinforcement method still has the following technical problems: First, the ends of the fiber mesh lack effective anchorage. As the main reinforcing material of the TRC plate, the fiber woven mesh is naturally truncated at the ends of the reinforcement layer, lacking reliable anchorage measures. This results in the fiber mesh's strength not being fully utilized, and the mesh easily slips or pulls out from the ends under stress, severely affecting the reinforcement effect. Although existing research has attempted to anchor the TRC plate to the beam bottom using end self-locking technology, these are mostly limited to single-stage self-locking anchorage, resulting in limited anchorage efficiency.
[0004] Second, the bonding layer performance is insufficient. In the existing technology, when ordinary cement mortar is used as a bonding layer, it has low shear strength, high brittleness, and is prone to aging and failure; when organic adhesives such as epoxy resin are used as reinforcing bonding layers, they are prone to aging in the natural environment, have poor fire resistance, and have poor compatibility with concrete, making it difficult to meet the requirements for long-term durability.
[0005] Third, there is a lack of effective end restraint structures. Existing precast TRC slab reinforced beams often experience end-peel brittle failure in the end region. The interface between the reinforcement layer and the concrete beam delaminates under the stress concentration at the end, leading to reinforcement failure.
[0006] Fourth, existing fiber mesh self-locking anchoring technologies are mostly used for confining concrete columns or for tensioning fiber cloth. Fiber meshes and fiber cloths differ fundamentally in structural morphology (mesh vs. sheet), stress mechanisms, and winding methods. Directly applying fiber cloth anchoring devices for columns to fiber mesh anchoring at the bottom of beams faces technical obstacles. The mesh nodes of fiber meshes are prone to stress concentration during winding, and the cooperative stress-bearing performance between fiber bundles is completely different from that of fiber cloth. Current technologies lack a graded, progressive self-locking anchoring scheme tailored to the characteristics of fiber meshes.
[0007] Therefore, there is an urgent need for a precast TRC plate reinforced beam structure and construction method that can effectively solve the problems of fiber mesh end anchoring, interface bonding and end peeling. Summary of the Invention
[0008] To address the problems of insufficient effective anchoring at the ends of the fiber mesh, inadequate bonding layer performance, and lack of effective end restraint structures in existing precast TRC slab reinforcement technologies, this invention provides a graded, progressive self-locking TRC precast slab reinforcement beam and end restraint method. This method achieves reliable self-locking anchoring at the ends of the fiber mesh, improves interface bonding performance, and effectively restrains end peeling, thereby significantly improving the overall load-bearing capacity and ductility of the reinforced beam.
[0009] To achieve the above objectives, the present invention provides the following technical solution: a graded, progressive, self-locking TRC precast slab reinforced beam, comprising a concrete beam body; A precast TRC slab, wherein the precast TRC slab is bonded to the bottom surface of the concrete beam by an adhesive layer; An alkali-resistant fiber mesh is disposed inside the precast TRC board, and the ends of the alkali-resistant fiber mesh extend beyond the ends of the precast TRC board; The self-locking anchor plate has two long slots parallel to each other along its width, with a spacing of 20-30mm between the two long slots. The end of the alkali-resistant fiber mesh extends out of the end of the prefabricated TRC plate and passes through the two long slots in sequence, and is wrapped around the surface of the self-locking anchor plate in the opposite direction to form a graded progressive S-shaped self-locking anchor. Each level of wrapping generates an anchoring force independently and is superimposed level by level. An inverted conical anchor bolt is inserted into the interior of the concrete beam, and the self-locking anchor plate is fixed to the bottom surface of the concrete beam by the inverted conical anchor bolt. A post-cast concrete layer is poured on the outside of the area where the self-locking anchor plate and the alkali-resistant fiber mesh are wrapped, thus enclosing the ends of the self-locking anchor plate and the alkali-resistant fiber mesh inside. U-shaped fiber cloth, which is wrapped in a U-shape around the outside of the combination of the concrete beam and the precast TRC slab.
[0010] Preferably, the concrete matrix of the precast TRC slab is a hybrid fiber concrete, the raw materials of which include cement, silica fume, fly ash, river sand, water, basalt fiber and shape memory alloy fiber, and the mix ratio is cement: silica fume: fly ash: river sand: water: basalt fiber: shape memory alloy fiber = 1:0.081:0.27:0.541:0.405:0.021:0.015.
[0011] Preferably, the cement is ordinary Portland cement PO 42.5, and the dosage is 380-500 kg / m³.3 ; The amount of silica fume used is 5%-10% of the total amount of cementitious materials; The amount of fly ash used is 20%-30% of the total amount of cementitious materials; The water-to-binder ratio is 0.30-0.40; The fiber content of the basalt fiber and the shape memory alloy fiber is 0.6%-0.9% each, and the total fiber content is controlled below 2.5%.
[0012] Preferably, the bonding layer is a polymer-modified cement mortar containing styrene-butadiene emulsion, the raw materials of which include cement, water, styrene-butadiene emulsion, sand and defoamer, and the mixing ratio is cement:water:styrene-butadiene emulsion:sand:defoamer = 1:0.26:0.15:1.5:0.0016.
[0013] Preferably, the self-locking anchor plate is a Q235 steel plate with a thickness of 5-8mm. The self-locking anchor plate is also provided with anchor bolt holes for the inverted conical anchor bolts to pass through. The width of the long slot is 4-6mm and the length is 100-130mm. The four edges of the self-locking anchor plate and the inner edge of the long slot are all rounded with a chamfer radius of 2-5mm.
[0014] Preferably, the alkali-resistant fiber mesh is a carbon fiber mesh, aramid fiber mesh, basalt fiber mesh, or alkali-resistant glass fiber mesh.
[0015] Preferably, the U-shaped fiber cloth is basalt fiber cloth, which wraps around the bottom of the reinforced beam and extends upward along both sides of the web of the concrete beam to form a circumferential constraint on the end of the reinforcement layer.
[0016] This invention provides an end constraint method for a graded, progressive self-locking TRC precast slab reinforced beam, used for constructing the aforementioned graded, progressive self-locking TRC precast slab reinforced beam, comprising the following steps: S1. Preparation of precast TRC panels: A formwork is erected, and the first layer of hybrid fiber-reinforced concrete matrix is poured into the mold, compacted, and smoothed. An alkali-resistant fiber mesh is laid on the surface of the first layer of matrix, stretched taut, and kept flat and wrinkle-free. The second layer of hybrid fiber-reinforced concrete matrix is then poured, compacted, and smoothed. After curing, the formwork is removed to obtain a precast TRC panel, with the end of the alkali-resistant fiber mesh extending beyond the end of the precast TRC panel. S2. Beam surface treatment: Roughen the bottom surface of the concrete beam, rinse it with water and let it dry. S3. Bonding layer construction: Prepare polymer-modified cement mortar containing styrene-butadiene emulsion according to the mixing ratio as the bonding layer. Apply the polymer-modified cement mortar evenly to the bottom surface of the concrete beam and the back of the precast TRC slab with a coating thickness of 3-5mm. Attach the precast TRC slab to the bottom surface of the concrete beam and press it firmly to ensure the bonding layer is evenly distributed. Cure until initial curing. S4. Self-locking anchor installation: The ends of the alkali-resistant fiber mesh extending from the end of the precast TRC plate are passed through the two long slots on the self-locking anchor plate, so that the fiber mesh forms an S-shaped winding path on the surface of the self-locking anchor plate, realizing graded progressive S-shaped self-locking anchor; holes are drilled at both ends of the bottom surface of the concrete beam, and inverted conical anchor bolts are inserted to fix the self-locking anchor plate to the bottom surface of the concrete beam through the inverted conical anchor bolts; S5. Construction of post-cast concrete layer: Set up formwork on the outside of the area where the self-locking anchor plate and alkali-resistant fiber mesh are wrapped, and pour post-cast concrete layer to completely wrap the ends of the self-locking anchor plate, the inverted conical anchor bolt and the alkali-resistant fiber mesh inside the concrete, so that the post-cast concrete layer and the precast TRC plate form a continuous reinforcement layer, and cure to the design strength. S6. U-shaped fiber cloth wrapping: A U-shaped fiber cloth is wrapped around the outside of the end area of the reinforcement layer. The fiber cloth impregnated with epoxy resin is wrapped around the bottom of the reinforcement beam and extends upward along both sides of the web of the concrete beam, tightly wrapping the precast TRC plate, the self-locking anchor plate and the concrete beam in a U-shape on the outside of the combination, and then cured.
[0017] Preferably, in step S4, before tightening the nut, washers are sequentially inserted into the end of the inverted conical anchor bolt, and then the nut is tightened to fix the self-locking anchor plate.
[0018] Compared with the prior art, the beneficial effects of the present invention are: The advantage of the precast TRC slab matrix material in this invention lies in utilizing the superelasticity and crack self-closing ability of SMA fibers, which can autonomously reduce crack width after load unloading, giving the matrix a self-repairing function. Basalt fibers play a role in reinforcing and restraining crack propagation. The synergistic effect of the two improves the compressive strength, flexural strength, and fracture toughness of concrete while endowing the matrix with self-repairing cracks, effectively improving the load-bearing capacity, ductility, and long-term durability of concrete beams. The advantage of the styrene-butadiene emulsion polymer-modified cement mortar in this invention lies in the fact that the styrene-butadiene emulsion forms a continuous, flexible polymer film at the interface during cement hydration. The polymer particles are evenly dispersed, and the pores are refined and dense, resulting in a significant narrowing or even disappearance of the interfacial bonding joint. Compared with ordinary cement mortar, the interfacial bonding strength of the bonding layer in this invention is significantly improved, and it also has excellent flexibility, water resistance, and long-term durability. This invention employs a self-locking anchor plate with two elongated slots parallel to each other along its width. An alkali-resistant fiber mesh is wound around the surface of the self-locking anchor plate to form an S-shaped self-locking anchor. This structure utilizes the tension of the fiber mesh itself to generate a self-locking effect that tightens as it is pulled. Each winding stage independently generates anchoring force, which is progressively superimposed. The anchoring force increases with increasing load, effectively preventing slippage and pull-out of the fiber mesh ends. Compared to traditional bolt clamping, the anchoring efficiency is significantly improved. The advantage of the U-shaped fiber cloth in this invention lies in the improvement of end restraint. The U-shaped wrapping of the ends of the precast TRC slab and concrete beam effectively restrains the peeling of the reinforcement layer ends and delays the initiation and expansion of peeling cracks. Attached Figure Description
[0019] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.
[0020] In the attached diagram: Figure 1 This is a schematic longitudinal section of the overall structure of the graded, progressive, self-locking TRC precast slab reinforced concrete beam in this invention. Figure 2 This is a detailed diagram of the self-locking anchor plate anchoring in this invention; Figure 3 This is a schematic elevation view of the overall structure of the graded, progressively self-locking TRC precast slab reinforced concrete beam in this invention. Figure 4 This is a three-dimensional view of the self-locking anchor plate in this invention; Figure 5 This is a top view of the self-locking anchor plate in this invention; Figure 6 This is a schematic diagram of the graded progressive S-shaped winding path of the fiber web in this invention.
[0021] In the diagram: 1-Concrete beam; 2-Precast TRC slab; 3-Bonding layer; 4-Alkali-resistant fiber mesh; 5-Inverted conical anchor bolt; 6-Washer; 7-Nut; 8-Self-locking anchor plate; 9-Post-cast concrete layer; 10-U-shaped fiber cloth. Detailed Implementation
[0022] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.
[0023] Example 1, as Figures 1-6As shown, this embodiment provides a graded, progressive self-locking TRC precast slab reinforced beam, including a concrete beam body 1; A precast TRC slab 2 is bonded to the bottom surface of the concrete beam 1 via an adhesive layer 3. Alkali-resistant fiber mesh 4 is disposed inside the precast TRC plate 2, and the end of the alkali-resistant fiber mesh 4 extends out of the end of the precast TRC plate 2; The self-locking anchor plate 8 has two long slots parallel to each other along its width. The distance between the two long slots is 20-30mm. The end of the alkali-resistant fiber mesh 4 extends out of the end of the prefabricated TRC plate 2 and passes through the two long slots in sequence and is wrapped around the surface of the self-locking anchor plate 8 in the opposite direction to form a graded progressive S-shaped self-locking anchor. Each level of wrapping generates an anchoring force independently and is superimposed level by level. An inverted conical anchor 5 is inserted into the interior of the concrete beam 1, and the self-locking anchor plate 8 is fixed to the bottom surface of the concrete beam 1 by the inverted conical anchor 5. Post-cast concrete layer 9 is poured on the outside of the area where the self-locking anchor plate 8 and the alkali-resistant fiber mesh 4 are wrapped, and the ends of the self-locking anchor plate 8 and the alkali-resistant fiber mesh 4 are wrapped inside. U-shaped fiber cloth 10, which is wrapped in a U-shape around the outside of the combination of the concrete beam 1 and the precast TRC slab 2.
[0024] It should be noted that the self-locking anchor plate in this embodiment is fundamentally different from existing anchor plates: The existing anchor plate has a single through hole. After the fiber cloth passes through the through hole, it is wrapped around the surface of the anchor plate. It belongs to a single-stage anchoring system. The fiber cloth is fixed after passing through only one hole. The anchoring force depends entirely on the friction between the fiber cloth and the anchor plate. The anchoring efficiency is limited. Moreover, as the load increases, relative slippage may occur between the fiber cloth and the anchor plate.
[0025] In this embodiment, two elongated slots are parallel to each other along the width of the self-locking anchor plate. The ends of the fiber mesh pass through the two slots in sequence and then wrap around the anchor plate surface in the opposite direction, forming an S-shaped winding path. The core innovation of this structure lies in the fact that each level of winding (i.e., the winding after the fiber mesh passes through the first slot and the winding after passing through the second slot) independently generates anchoring force, and the anchoring forces at each level are superimposed—the greater the load, the tighter the fiber mesh covers the anchor plate, and the stronger the self-locking effect. This is the essential meaning of "graded progressive" anchoring, which is completely different from the existing single-stage anchoring in terms of anchoring mechanism.
[0026] The structural differences between fiber mesh and fiber cloth affect the anchoring method: Fiber cloth is a continuous sheet structure with tightly arranged fibers in the width direction, exhibiting strong integrity. Effective anchoring can be achieved simply by passing through a single through-hole. In contrast, fiber mesh is composed of interwoven warp and weft fiber bundles, with abrupt thickness changes at the mesh nodes. If only a single through-hole is used, stress concentration easily occurs at the edge of the hole when the mesh nodes are under stress, leading to premature fiber bundle breakage. This embodiment uses two elongated slots to form an S-shaped winding path, distributing the tensile force among the various winding segments of the fiber mesh, effectively avoiding stress concentration and fully utilizing the cooperative stress-bearing performance between the fiber bundles.
[0027] Advantageously, the concrete matrix of the precast TRC panel 2 is a hybrid fiber concrete, the raw materials of which include cement, silica fume, fly ash, river sand, water, basalt fiber and shape memory alloy fiber, and the mix ratio is cement: silica fume: fly ash: river sand: water: basalt fiber: shape memory alloy fiber = 1:0.081:0.27:0.541:0.405:0.021:0.015.
[0028] Advantageously, the cement is ordinary Portland cement PO 42.5, with a dosage of 380-500 kg / m³. 3 ; The amount of silica fume used is 5%-10% of the total amount of cementitious materials; The amount of fly ash used is 20%-30% of the total amount of cementitious materials; The water-to-binder ratio is 0.30-0.40; The fiber content of the basalt fiber and the shape memory alloy fiber is 0.6%-0.9% each, and the total fiber content is controlled below 2.5%; the river sand is natural river sand with a particle size of no more than 2.5mm; the basalt fiber is 12mm long and 15μm in diameter; the shape memory alloy fiber is NiTi alloy fiber with a diameter of 0.2mm and a length of 20mm.
[0029] Advantageously, the bonding layer 3 is a polymer-modified cement mortar containing styrene-butadiene emulsion, the raw materials of which include cement, water, styrene-butadiene emulsion, sand and defoamer, and the mixing ratio is cement:water:styrene-butadiene emulsion:sand:defoamer = 1:0.26:0.15:1.5:0.0016; The solid content of the styrene-butadiene emulsion is 48%, and the defoamer is a polyether defoamer.
[0030] Advantageously, the self-locking anchor plate 8 is made of Q235 steel plate with a thickness of 5-8mm. The self-locking anchor plate 8 is also provided with anchor bolt holes for the inverted conical anchor bolts 5 to pass through. The width of the long slot is 4-6mm and the length is 100-130mm. The four edges of the self-locking anchor plate 8 and the inner edge of the long slot are all rounded with a chamfer radius of 2-5mm to avoid stress concentration or fiber damage caused by the fiber mesh contacting the sharp edge of the steel plate during the winding process.
[0031] Advantageously, the alkali-resistant fiber mesh 4 is a carbon fiber mesh, aramid fiber mesh, basalt fiber mesh, or alkali-resistant glass fiber mesh.
[0032] Advantageously, the U-shaped fiber cloth 10 is basalt fiber cloth, which wraps around the bottom of the reinforced beam and extends upward along the two webs of the concrete beam 1 to form a circumferential constraint on the end of the reinforced layer.
[0033] Example 2: This example provides an end constraint method for a graded, progressive self-locking TRC precast slab reinforced beam, used for constructing the graded, progressive self-locking TRC precast slab reinforced beam, including the following steps: S1. Preparation of prefabricated TRC panels: The formwork mold is 2300mm long, 150mm wide (the same as the bottom width of the concrete beam), and 30mm thick. The alkali-resistant fiber mesh 4 is made of basalt fiber mesh and extends 500mm beyond the end of the precast TRC slab 2. The first 15mm thick mixed fiber concrete matrix is poured into the mold, vibrated to compact and smoothed; then the alkali-resistant fiber mesh 4 is laid on the surface of the lower matrix, and the mesh is stretched and tightened with heavy objects to ensure that the mesh remains flat and wrinkle-free; then the second 15mm thick mixed fiber concrete matrix is poured, vibrated to compact and smoothed, and the mold is removed after 7 days of curing to obtain the precast TRC board 2. The end of the alkali-resistant fiber mesh 4 extends 500mm beyond the end of the board during the precasting process. S2. Beam surface treatment: The bottom surface of the concrete beam 1 is roughened to form a rough interface. It is then rinsed with water and allowed to air dry naturally to improve the bonding performance between the bonding layer and the beam. S3. Bonding layer construction: Prepare a polymer-modified cement mortar containing styrene-butadiene emulsion as the bonding layer 3 according to the mixing ratio. Apply the polymer-modified cement mortar evenly to the bottom surface of the concrete beam 1 and the back of the precast TRC plate 2 with a coating thickness of 3-5mm. Attach the precast TRC plate 2 to the bottom surface of the concrete beam 1 and press it to make the bonding layer evenly distributed. Cure until preliminary curing. S4. Self-locking anchor installation: The alkali-resistant fiber mesh 4 extending from the end of the prefabricated TRC plate 2 is passed through two long slots on the self-locking anchor plate 8, so that the fiber mesh forms an S-shaped winding path on the surface of the self-locking anchor plate, realizing graded progressive S-shaped self-locking anchoring; this structure uses the tension of the fiber mesh itself to generate a self-locking effect that gets tighter and tighter as it is pulled, and each level of winding independently generates anchoring force and is superimposed level by level. Then, drill holes at predetermined positions at both ends of the bottom surface of the concrete beam 1, with the hole positions corresponding to the anchor bolt holes on the self-locking anchor plate 8 and the mesh holes at the ends of the alkali-resistant fiber mesh 4. Use an 18mm drill bit to drill the holes, with a hole depth of not less than 130mm. After cleaning the holes, inject anchoring adhesive. Pass the inverted conical anchor bolts 5 through the anchor bolt holes on the self-locking anchor plate 8 and the mesh holes at the ends of the alkali-resistant fiber mesh 4 in sequence, so that the self-locking anchor plate 8 fits against the bottom surface of the beam. Then, insert the anchor bolts into the holes, rotate them to insert them, and ensure that they are perpendicular to the surface of the beam. Wipe away the overflowing anchoring adhesive and wait for the anchoring adhesive to cure. Insert the washers 6 into the ends of the anchor bolts in sequence, tighten the nuts 7, and fix the self-locking anchor plate 8 to the bottom surface of the concrete beam 1. S5. Construction of post-cast concrete layer: Formwork is erected on the outside of the area where the self-locking anchor plate 8 and alkali-resistant fiber mesh 4 are wrapped, and a post-cast concrete layer 9 is poured to completely enclose the self-locking anchor plate 8, the end of the inverted conical anchor bolt 5, the end of the alkali-resistant fiber mesh 4, and the wrapping nodes inside the concrete. The surface is smoothed so that the post-cast concrete layer 9 and the precast TRC plate 2 form a continuous reinforcement layer. After curing for 7 days, the bonding layer 3 and the post-cast concrete layer 9 reach the design strength. S6, wrapped in U-shaped fiber cloth: Finally, wrap a U-shaped fiber cloth 10 around the outer side of the end area of the reinforcement layer; mix the two components of epoxy resin adhesive A and B in a ratio of 100:31 and stir evenly; lay the cut fiber cloth flat on the plastic sheet, pour in the evenly mixed epoxy resin adhesive, spread it evenly on the surface with a brush, and scrape out the air bubbles under the fiber cloth with a scraper to ensure that the epoxy resin adhesive fully wets the fiber cloth; wrap the evenly wetted fiber cloth around the bottom of the reinforcement beam, extend it upward along the web of both sides of the beam, and tightly wrap it in a U-shape around the outside of the combination of the precast slab, self-locking anchor plate and beam body. After wrapping, scrape out the air bubbles generated between the fiber cloth and the concrete surface with a scraper, and then apply a layer of epoxy resin adhesive to the surface of the fiber cloth to ensure that the fiber cloth is firmly bonded to the concrete surface. Curing is completed after 7 days.
[0034] Advantageously, in step S4, before tightening the nut 7, washers 6 are sequentially inserted into the end of the inverted conical anchor bolt 5, and then the nut 7 is tightened to fix the self-locking anchor plate 8.
[0035] This embodiment uses a self-locking anchor plate in conjunction with fiber mesh winding to achieve a self-locking anchoring effect that tightens as it is pulled, effectively preventing slippage at the ends of the fiber mesh; the use of U-shaped fiber cloth to wrap the ends effectively constrains the peeling stress; and the use of SMA-basalt hybrid fiber concrete as the matrix of the precast TRC slab effectively improves the compressive strength, flexural strength, and fracture toughness of the concrete, and endows the matrix with self-healing ability for cracks; overall, it enhances the load-bearing capacity and ductility of the reinforced beam.
[0036] Example 3 The difference between this embodiment and Embodiment 1 is that: the alkali-resistant fiber mesh (4) is made of carbon fiber mesh; the self-locking anchor plate (8) has a thickness of 8mm, a width of 150mm, a long slot width of 6mm, a length of 130mm, a spacing of 30mm between the two holes, and a chamfer radius of 5mm; the U-shaped fiber cloth (10) has 2 wrapping layers. The remaining structure and construction method are the same as in Embodiment 2.
[0037] Example 4 The difference between this embodiment and Embodiment 1 is that: the alkali-resistant fiber mesh (4) is made of aramid fiber mesh; the diameter of the inverted conical anchor bolt (5) is 20mm, and the strength grade is 10.9; the thickness of the self-locking anchor plate (8) is 5mm, the width of the long slot is 4mm, the length is 100mm, the distance between the two holes is 20mm, and the chamfer radius is 2mm. The rest of the structure and construction method are the same as in Embodiment 2.
[0038] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.
[0039] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A graded, progressive, self-locking TRC precast slab reinforced beam, characterized in that: Including concrete beams (1); A precast TRC slab (2) is bonded to the bottom surface of the concrete beam (1) by an adhesive layer (3); Alkali-resistant fiber mesh (4) is disposed inside the precast TRC plate (2), and the end of the alkali-resistant fiber mesh (4) extends out of the end of the precast TRC plate (2); The self-locking anchor plate (8) has two long slots parallel to each other along the width direction. The distance between the two long slots is 20-30mm. The end of the alkali-resistant fiber mesh (4) extends out of the end of the prefabricated TRC plate (2) and passes through the two long slots in sequence and is wrapped around the surface of the self-locking anchor plate (8) in the opposite direction to form a graded progressive S-shaped self-locking anchor. Each level of wrapping generates an anchoring force independently and is superimposed level by level. An inverted conical anchor (5) is inserted into the interior of the concrete beam (1), and the self-locking anchor plate (8) is fixed to the bottom surface of the concrete beam (1) by the inverted conical anchor (5); Post-cast concrete layer (9) is poured on the outside of the area where the self-locking anchor plate (8) and the alkali-resistant fiber mesh (4) are wrapped, and the ends of the self-locking anchor plate (8) and the alkali-resistant fiber mesh (4) are wrapped inside. U-shaped fiber cloth (10) is wrapped in a U-shape around the outside of the combination of the concrete beam (1) and the precast TRC plate (2).
2. The graded, progressive, self-locking TRC precast slab reinforced beam according to claim 1, characterized in that: The concrete matrix of the precast TRC slab (2) is a hybrid fiber concrete. The raw materials of the hybrid fiber concrete include cement, silica fume, fly ash, river sand, water, basalt fiber and shape memory alloy fiber. The mix ratio is cement: silica fume: fly ash: river sand: water: basalt fiber: shape memory alloy fiber = 1:0.081:0.27:0.541:0.405:0.021:0.
015.
3. The graded, progressive, self-locking TRC precast slab reinforced beam according to claim 2, characterized in that: The cement is ordinary Portland cement PO 42.5, with a dosage of 380-500 kg / m³. 3 ; The amount of silica fume used is 5%-10% of the total amount of cementitious materials; The amount of fly ash used is 20%-30% of the total amount of cementitious materials; The water-to-binder ratio is 0.30-0.40; The fiber content of the basalt fiber and the shape memory alloy fiber is 0.6%-0.9% respectively, and the total fiber content is controlled below 2.5%.
4. The graded, progressive self-locking TRC precast slab reinforced beam according to claim 3, characterized in that: The bonding layer (3) is a polymer-modified cement mortar containing styrene-butadiene emulsion. Its raw materials include cement, water, styrene-butadiene emulsion, sand and defoamer. The mixing ratio is cement:water:styrene-butadiene emulsion:sand:defoamer = 1:0.26:0.15:1.5:0.0016.
5. A graded, progressive, self-locking TRC precast slab reinforced beam according to claim 4, characterized in that: The self-locking anchor plate (8) is made of Q235 steel plate with a thickness of 5-8mm. The self-locking anchor plate (8) is also provided with anchor bolt holes for the inverted conical anchor bolts (5) to pass through. The width of the long slot is 4-6mm and the length is 100-130mm. The four edges of the self-locking anchor plate (8) and the inner edge of the long slot are all rounded with a chamfer radius of 2-5mm.
6. A graded, progressive, self-locking TRC precast slab reinforced beam according to claim 5, characterized in that: The alkali-resistant fiber mesh (4) is a carbon fiber mesh, aramid fiber mesh, basalt fiber mesh or alkali-resistant glass fiber mesh.
7. A graded, progressive, self-locking TRC precast slab reinforced beam according to claim 6, characterized in that: The U-shaped fiber cloth (10) is basalt fiber cloth. The U-shaped fiber cloth (10) passes around the bottom of the reinforced beam and extends upward along the two sides of the web of the concrete beam (1), forming a circumferential constraint on the end of the reinforced layer.
8. A method for end restraint of a graded, progressively self-locking TRC precast slab reinforced beam, used for constructing a graded, progressively self-locking TRC precast slab reinforced beam as described in any one of claims 1-7, characterized in that, Includes the following steps: S1. Preparation of precast TRC slab: Set up a formwork, pour the first layer of mixed fiber concrete matrix in the formwork, vibrate to compact and smooth it; lay the alkali-resistant fiber mesh (4) on the surface of the first layer matrix, straighten and tighten it and keep it flat and wrinkle-free; then pour the second layer of mixed fiber concrete matrix, vibrate to compact and smooth it, and remove the formwork after curing to obtain the precast TRC slab (2), with the end of the alkali-resistant fiber mesh (4) extending out of the end of the precast TRC slab (2); S2. Beam surface treatment: Roughen the bottom surface of the concrete beam (1), rinse it with water and let it dry. S3, Bonding layer construction: Prepare polymer-modified cement mortar containing styrene-butadiene emulsion as bonding layer (3) according to the mixing ratio. Apply the polymer-modified cement mortar evenly to the bottom surface of the concrete beam (1) and the back of the precast TRC plate (2) with a coating thickness of 3-5mm. Attach the precast TRC plate (2) to the bottom surface of the concrete beam (1) and press it to make the bonding layer evenly distributed. Cure until preliminary curing. S4. Self-locking anchor installation: The ends of the alkali-resistant fiber mesh (4) extending from the end of the precast TRC plate (2) are respectively passed through the two long slots on the self-locking anchor plate (8), so that the fiber mesh forms an S-shaped winding path on the surface of the self-locking anchor plate, realizing graded progressive S-shaped self-locking anchor; Drill holes at both ends of the bottom surface of the concrete beam (1), and insert inverted conical anchor bolts (5) to fix the self-locking anchor plate (8) to the bottom surface of the concrete beam (1) through the inverted conical anchor bolts (5); S5. Construction of post-cast concrete layer: Formwork is erected on the outside of the area where the self-locking anchor plate (8) and alkali-resistant fiber mesh (4) are wrapped, and the post-cast concrete layer (9) is poured. The ends of the self-locking anchor plate (8), the inverted cone anchor bolt (5) and the alkali-resistant fiber mesh (4) are completely wrapped in the concrete, so that the post-cast concrete layer (9) and the precast TRC plate (2) form a continuous reinforcement layer, and are cured to the design strength. S6. U-shaped fiber cloth wrapping: A U-shaped fiber cloth (10) is wrapped around the outside of the end area of the reinforcement layer. The fiber cloth impregnated with epoxy resin is wrapped around the bottom of the reinforcement beam and extends upward along the two sides of the web of the concrete beam (1). It is tightly wrapped in a U-shape around the outside of the combination of the precast TRC plate (2), the self-locking anchor plate (8) and the concrete beam (1) and cured.
9. The end constraint method for a graded, progressive self-locking TRC precast slab reinforced beam according to claim 8, characterized in that: In step S4, before tightening the nut (7), washers (6) are sequentially inserted into the end of the inverted conical anchor bolt (5), and then the nut (7) is tightened to fix the self-locking anchor plate (8).