A chopped-continuous fiber composite reinforced repair composite material and a construction method thereof

Abstract

The present invention provides a short-cut continuous fiber composite reinforced repair composite material and a construction method thereof, comprising a low fiber content layer, a medium fiber content layer, and a surface layer which are arranged in sequence, wherein the low fiber content layer and the medium fiber content layer both contain short-cut reinforced fibers, the short-cut reinforced fibers are at least one of PVA fibers and PE fibers, the low fiber content layer contains 0.08%-0.3% of short-cut reinforced fibers, the medium fiber content layer contains 0.15%-0.6% of short-cut reinforced fibers, and the surface layer contains a three-dimensional fabric of synthetic fiber untwisted yarn, and the thickness of the three-dimensional fabric of synthetic fiber untwisted yarn is 3mm-5mm. The present invention adopts a three-layer gradient structure of bottom, middle, and surface, and configures denser fibers on the surface with greater stress, thereby improving the fiber reinforcement efficiency and the structural repair effect, thereby avoiding the phenomenon of bulging of the repair layer caused by the difficulty in dispersing and agglomerating synthetic fibers.

Description

Technical Field

[0001] The invention relates to the technical field of repair materials, and in particular to a chopped-continuous fiber composite reinforced repair composite material and a construction method thereof. Background Art

[0002] There are many synthetic fibers (such as polyvinyl alcohol (PVA), polyethylene (PE), polyester (PET), etc.) that can be used as reinforcing components of cement-based materials to make high-toughness cement products. ECC (ultra-high ductility concrete) materials, which are developed by combining high-dosage synthetic fibers with cement matrix, are an important choice for repairing and reinforcing wall and road and bridge structures. In most cases, the above-mentioned reinforcing fibers are applied in a short-cut manner, and the fiber length is usually a few millimeters to tens of millimeters. When used for structural repair, the short-cut fibers are usually mixed with cement, admixtures, sand and additives, and then spread on the surface of the structure to be repaired by spraying, smearing, etc., and then leveled, solidified and hardened.

[0003] Since synthetic fibers are difficult to disperse evenly in the cement matrix, in order to disperse the fibers as much as possible and form a composite material with excellent texture, when the fibers are added to the cement mortar and stirred, it is often necessary to disperse the fibers manually or add the fibers to the mixer in small amounts one by one.

[0004] However, since synthetic fibers are light and fluffy, and have a very low bulk density, their loose volume is much larger than the volume of the cement matrix when used in high dosages. Therefore, it is difficult to evenly disperse the fibers during the mixing process, and the fibers are prone to agglomeration and entanglement, resulting in poor workability of the mixture, which brings construction difficulties. Due to the serious fiber agglomeration phenomenon, many "bulges" often appear on the surface of the structure after repair and smoothing. The "bulge" phenomenon is caused by the fiber agglomerates entraining air into the cement matrix, and the bubbles are compressed by external forces during the smoothing process, and the bubbles gradually swell after the external force is removed. These shortcomings not only reduce the construction efficiency, but also seriously affect the quality of the repair project. Summary of the invention

[0005] The present invention adopts an organic combination of short-cut and continuous fibers with different fiber dosages and different matrix compositions to form a three-layer gradient structure of bottom, middle and surface, and configures denser fibers on the surface with greater stress, thereby improving the fiber reinforcement efficiency and the structural repair effect, thereby avoiding the phenomenon of bulging of the repair layer caused by the difficulty in dispersing and agglomerating synthetic fibers.

[0006] In order to solve the above problems, the present invention provides a chopped-continuous fiber composite reinforced repair composite material, comprising a low fiber content layer, a medium fiber content layer, and a surface layer which are arranged in sequence, the low fiber content layer and the medium fiber content layer both contain chopped reinforcing fibers, the chopped reinforcing fibers are at least one of PVA fibers and PE fibers, the low fiber content layer contains 0.08%-0.3% of the chopped reinforcing fibers, the medium fiber content layer contains 0.15%-0.6% of the chopped reinforcing fibers, the surface layer contains a synthetic fiber untwisted yarn three-dimensional fabric, and the thickness of the synthetic fiber untwisted yarn three-dimensional fabric is 3mm-5mm.

[0007] In one embodiment of the present invention, the low-fiber-content cement mortar constituting the low-fiber-content layer contains: 35%-40% of silicate cement, 30%-36% of fly ash, 8%-12% of metakaolin, 15%-20% of washed fine sand, 3%-7% of rubber powder, and 0.5%-1.5% of high-efficiency water reducing agent;

[0008] The medium fiber content cement mortar constituting the medium fiber content layer contains: 35%-40% silicate cement, 30%-36% fly ash, 3%-7% silica fume, 3%-7% kaolin, 15%-20% washed ground sand, and 0.5%-1.5% high-efficiency water reducing agent.

[0009] In one embodiment of the present invention, the volume ratio of low-fiber-content cement mortar to short-cut reinforcing fibers is 100:(0.2-0.3), or the mass ratio of low-fiber-content cement mortar to short-cut reinforcing fibers is 100:(0.08-0.1), and the compressive strength of the low-fiber-content layer reaches 30MPa-50MPa;

[0010] The volume ratio of medium fiber content cement mortar to short chopped reinforcing fibers is 100:(0.4-0.6), or the mass ratio of medium fiber content cement mortar to short chopped reinforcing fibers is 100:(0.15-0.2), and the compressive strength of the medium fiber content layer reaches 60MPa-80MPa.

[0011] In one example of the present invention, a fiber grid is also provided in the medium fiber content layer, the fiber grid has a grid length of 5mm-10mm and a width of 5mm-10mm, and the fiber grid is one or more of bidirectional carbon fiber, alkali-resistant glass fiber, basalt fiber, polyvinyl alcohol fiber, high modulus polyethylene fiber, and steel wire grid.

[0012] In one embodiment of the present invention, it further comprises: a plurality of penetration pieces, each of which passes through the low fiber content layer, the medium fiber content layer, and the surface layer.

[0013] The present invention also provides a construction method of a chopped-continuous fiber composite reinforced repair composite material, which is used to lay the chopped-continuous fiber composite reinforced repair composite material. The specific construction steps include:

[0014] S100: Laying low-fiber cement mortar on the surface of the area to be repaired to form a low-fiber layer;

[0015] S200: medium fiber content cement mortar is laid on the low fiber content layer to form a medium fiber content layer;

[0016] S300: laying a synthetic fiber untwisted yarn three-dimensional fabric on the medium fiber content layer, and rolling the synthetic fiber untwisted yarn three-dimensional fabric with a roller until the synthetic fiber untwisted yarn three-dimensional fabric is pressed into the medium fiber content cement mortar, and the medium fiber content cement mortar emerges from the synthetic fiber untwisted yarn three-dimensional fabric, thereby forming a surface layer tightly connected with the medium fiber content layer;

[0017] S400: The surface of the facing layer is subjected to exhaust treatment with a roller with burrs, and then the surface is smoothed with a roller to obtain a chopped-continuous fiber composite reinforced repair composite material.

[0018] In one example of the present invention, in S100, before laying the low-fiber content cement mortar, the area to be repaired is cleaned and roughened, and an interface agent is coated or sprayed on the surface of the area to be repaired; after laying the low-fiber content cement mortar, the low-fiber content cement mortar is leveled to form a low-fiber content layer.

[0019] In one embodiment of the present invention, S200 specifically includes the following steps:

[0020] S210: before the low-fiber content cement mortar is initially set, a fiber mesh is laid on the surface of the low-fiber content layer, and the edges of the fiber mesh are nailed to the sides of the area to be repaired, and the middle part of the fiber mesh is embedded in the low-fiber content cement mortar;

[0021] S220: After the low-fiber content cement mortar has initially set, medium-fiber content cement mortar is laid on the fiber grid to form a medium-fiber content layer.

[0022] In an example of the present invention, S400 specifically includes the following steps:

[0023] S410: Use a roller with burrs to exhaust the surface of the facing layer, and then smooth the surface with a roller;

[0024] S420: The penetration piece is sequentially passed through the surface layer, the medium fiber content layer and the low fiber content layer until one end of the penetration piece penetrates into the base layer of the area to be repaired, and multiple penetration pieces are arranged in the entire repair area to obtain a short-cut-continuous fiber composite reinforced repair composite material.

[0025] In one embodiment of the present invention, S300 specifically includes the following steps:

[0026] S310: laying a three-dimensional fabric of synthetic fiber untwisted yarn on the medium fiber content layer, and rolling the three-dimensional fabric of synthetic fiber untwisted yarn with a roller until the three-dimensional fabric of synthetic fiber untwisted yarn is pressed into the cement mortar with the medium fiber content, and the cement mortar with the medium fiber content emerges from the three-dimensional fabric of synthetic fiber untwisted yarn, thereby forming a first surface layer tightly connected with the medium fiber content layer;

[0027] S320: laying medium fiber content cement mortar on the first surface layer, and then repeating the step of S310 to form a second surface layer tightly connected to the first surface layer;

[0028] S330: Repeat step S320 0-2 times, and finally obtain multiple surface layers tightly connected to the medium fiber content layer.

[0029] Compared with the prior art, the advantages of the present invention are:

[0030] (1) The present invention uses short-cut and continuous fibers with different fiber dosages and different matrix compositions to form a three-layer gradient structure of bottom, middle and surface, and configures denser fibers on the surface with greater stress, thereby improving the fiber reinforcement efficiency and enhancing the structural repair effect;

[0031] (2) The chopped fibers used in the present invention are used in low and medium dosages when preparing cement mortar. In this way, the fibers are more easily dispersed in the cement mortar during the mixing process, thereby avoiding the phenomenon of bulging of the repair composite material due to fiber agglomeration. In the surface area of ​​the repair composite material where stress is relatively concentrated, a three-dimensional fabric of synthetic fiber untwisted yarn is used, and cement mortar is filled therein with external pressure. Although the fiber dosage in this area is very high, the fiber distribution is very uniform, and no agglomeration or bulging occurs, thereby improving the construction efficiency of the material and reducing the waste of the material.

[0032] (3) The measures adopted by the present invention, such as rolling with a burr roller, smoothing, and injecting into the penetration piece, help to discharge the bubbles inside the repair layer during the solidification and hardening process of the cement mortar, and stabilize the fiber grid. It also helps to closely bond the entire repair layer and each layer after the repair layer hardens, thereby greatly improving the quality of structural repair from the inside to the outside. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic structural diagram of a chopped-continuous fiber composite reinforced repair composite material provided by an embodiment of the present invention.

[0034] Description of reference numerals:

[0035] 100-base; 200-through-piece; 310-low fiber content layer; 320-medium fiber content layer; 330-surface layer; 340-fiber mesh. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below.

[0037] The present embodiment provides a chopped-continuous fiber composite reinforced repair composite material, comprising a low fiber content layer, a medium fiber content layer, and a surface layer arranged in sequence, the low fiber content layer and the medium fiber content layer both contain chopped reinforcing fibers, the chopped reinforcing fibers are at least one of PVA fibers and PE fibers, the low fiber content layer contains 0.08%-0.3% of chopped reinforcing fibers, the medium fiber content layer contains 0.15%-0.6% of chopped reinforcing fibers, the surface layer contains synthetic fiber untwisted yarn three-dimensional fabric, and the thickness of the synthetic fiber untwisted yarn three-dimensional fabric is 3mm-5mm.

[0038] Among them, the three-dimensional fabric of synthetic fiber untwisted yarn is woven from fibers such as PVA, PE or PET, and is in the form of dense filaments, mainly composed of warp fiber bundles. The thickness of the three-dimensional fabric in its natural state is 3mm-5mm.

[0039] Preferably, the three-dimensional fabric of synthetic fiber untwisted yarn is woven from PVA and PE fibers and has a thickness of 4 mm.

[0040] Among them, the low-fiber cement mortar that constitutes the low-fiber content layer contains: 35%-40% of Portland cement, 30%-36% of fly ash, 8%-12% of kaolin, 15%-20% of washed fine sand, 3%-7% of glue powder, and 0.5%-1.5% of high-efficiency water reducer; the medium-fiber cement mortar that constitutes the medium-fiber content layer contains: 35%-40% of Portland cement, 30%-36% of fly ash, 3%-7% of silica fume, 3%-7% of kaolin, 15%-20% of washed ground sand, and 0.5%-1.5% of high-efficiency water reducer.

[0041] Preferably, the low-fiber cement mortar contains: 38% silicate cement, 34% fly ash, 10% kaolin, 18% washed fine sand, 5% rubber powder, and 1% high-efficiency water reducing agent.

[0042] Preferably, the medium fiber content cement mortar contains: 38% silicate cement, 34% fly ash, 5% silica fume, 5% metakaolin, 18% washed ground sand, and 1% high-efficiency water reducing agent.

[0043] Among them, the volume ratio of low fiber content cement mortar to short chopped reinforcing fiber is 100: (0.2-0.3), or the mass ratio of low fiber content cement mortar to short chopped reinforcing fiber is 100: (0.08-0.1), and the compressive strength of the low fiber content layer reaches 30MPa-50MPa. That is, the content of short chopped reinforcing fiber in low fiber content cement mortar is 1 / 10 to 1 / 5 of that in normal ECC.

[0044] Among them, the volume ratio of medium fiber content cement mortar to short chopped reinforcing fiber is 100: (0.4-0.6), or the mass ratio of medium fiber content cement mortar to short chopped reinforcing fiber is 100: (0.15-0.2), and the compressive strength of the medium fiber content layer reaches 60MPa-80MPa. That is, the content of short chopped reinforcing fiber in medium fiber content cement mortar is about 1 / 3 of the content in normal ECC.

[0045] Preferably, the volume ratio of low fiber content cement mortar to chopped reinforcing fibers is 100:0.28.

[0046] Preferably, the volume ratio of low fiber content cement mortar to chopped reinforcing fibers is 100:0.23.

[0047] Preferably, the mass ratio of low fiber content cement mortar to chopped reinforcing fibers is 100:0.09.

[0048] Preferably, the volume ratio of the medium fiber content cement mortar to the chopped reinforcing fibers is 100:0.5.

[0049] Preferably, the mass ratio of the medium fiber content cement mortar to the chopped reinforcing fibers is 100:0.16.

[0050] Preferably, the mass ratio of the medium fiber content cement mortar to the chopped reinforcing fibers is 100:0.18.

[0051] Since the gradient repair layer structure is adopted in the present invention, the fibers in the repair composite material of the present invention are not easy to clump, thereby avoiding the occurrence of bulging. From the fiber dosage, the fiber content in the low fiber dosage layer directly in contact with the wall or road bridge structure to be repaired is the smallest, only 1 / 10 to 1 / 5 of the usual dosage. A small amount of fiber is added to the bottom layer of the repair composite material - the low fiber dosage layer, mainly to increase the bonding strength between the low fiber dosage layer and the substrate and the bonding strength between the low fiber dosage layer and the medium fiber dosage layer.

[0052] In the middle layer, that is, the medium fiber content layer, the fiber content is increased, which can effectively resist the gradually increasing bending stress. In the surface layer, that is, the surface layer, due to the addition of the three-dimensional fabric of synthetic fiber untwisted yarn and the compression of the three-dimensional fabric during the surface smoothing process during construction, the density of the fibers at the surface is the highest, and the crack resistance and bending resistance of the surface are also the strongest. This gradient distribution greatly improves the reinforcement efficiency of the fiber without increasing the total fiber content.

[0053] Among them, a fiber grid is also arranged in the medium fiber content layer. The fiber grid has a grid length of 5mm-10mm and a width of 5mm-10mm. The fiber grid is one or more of bidirectional carbon fiber, alkali-resistant glass fiber, basalt fiber, polyvinyl alcohol fiber, high modulus polyethylene fiber, and steel wire grid.

[0054] Preferably, the fiber grid is bidirectional carbon fiber.

[0055] Preferably, the fiber mesh is alkali-resistant glass fiber.

[0056] Preferably, the fiber grid is a double-layer structure consisting of bidirectional carbon fibers and alkali-resistant glass fibers.

[0057] Preferably, the fiber grid is a double-layer structure consisting of bidirectional carbon fibers and polyvinyl alcohol fibers.

[0058] The repair composite material also includes: a plurality of penetration pieces, and the penetration pieces all pass through the low fiber content layer, the medium fiber content layer, and the surface layer.

[0059] The penetration piece may be at least one of a steel wire nail, a tungsten steel column nail, and an iron nail.

[0060] The present invention also provides a construction method of a chopped-continuous fiber composite reinforced repair composite material, which is used to lay the chopped-continuous fiber composite reinforced repair composite material. The specific construction steps include:

[0061] S100: Laying low-fiber cement mortar on the surface of the area to be repaired to form a low-fiber layer;

[0062] S200: medium fiber content cement mortar is laid on the low fiber content layer to form a medium fiber content layer;

[0063] S300: laying a synthetic fiber untwisted yarn three-dimensional fabric on the medium fiber content layer, and rolling the synthetic fiber untwisted yarn three-dimensional fabric with a roller until the synthetic fiber untwisted yarn three-dimensional fabric is pressed into the medium fiber content cement mortar, and the medium fiber content cement mortar emerges from the synthetic fiber untwisted yarn three-dimensional fabric, thereby forming a surface layer tightly connected with the medium fiber content layer;

[0064] S400: The surface of the facing layer is subjected to exhaust treatment with a roller with burrs, and then the surface is smoothed with a roller to obtain a chopped-continuous fiber composite reinforced repair composite material.

[0065] The method of the invention adopts a simple and effective degassing operation, and uses a roller with burrs and a conventional roller in combination to quickly remove bubbles in the fiber-cement mixture, thereby achieving the effect of a dense internal structure and a smooth and flat surface.

[0066] The roller with burrs is a rubber roller with burrs, and the roller with burrs can also be replaced by a wire brush; the roller is a rubber roller.

[0067] Among them, in S100, before laying the low-fiber content cement mortar, the area to be repaired is cleaned and roughened, and an interface agent is coated or sprayed on the surface of the area to be repaired; after laying the low-fiber content cement mortar, the low-fiber content cement mortar is leveled to form a low-fiber content layer.

[0068] Among them, the interface agent is mainly selected from epoxy resin interface agents and vinyl acetate-ethylene interface agents.

[0069] Among them, the low-fiber cement mortar is prepared by mixing silicate cement, fly ash, kaolin, rubber powder, washed fine sand, high-efficiency water reducing agent and short-cut reinforcing fiber, stirring at a low speed for 1min-2min, and then stirring at a high speed for 3min-5min.

[0070] Among them, the medium fiber content cement mortar is prepared by mixing silicate cement, fly ash, silica fume, kaolin, washed ground sand, high-efficiency water reducer and chopped reinforcing fiber, stirring at a low speed for 2 minutes to 3 minutes, and then stirring at a high speed for 4 minutes to 6 minutes.

[0071] Wherein, S200 specifically includes the following steps:

[0072] S210: before the low-fiber content cement mortar is initially set, a fiber mesh is laid on the surface of the low-fiber content layer, and the edges of the fiber mesh are nailed to the sides of the area to be repaired, and the middle part of the fiber mesh is embedded in the low-fiber content cement mortar;

[0073] S220: After the low-fiber content cement mortar has initially set, medium-fiber content cement mortar is laid on the fiber grid to form a medium-fiber content layer.

[0074] In order to strengthen the connectivity between the low fiber content layer and the medium fiber content layer and prevent the medium fiber content layer from slipping with the low fiber content layer under the action of external force, a layer of polyurethane cement can be applied on the fiber mesh before laying the fiber mesh. The polyurethane cement contains: 38% silicate cement, 34% fly ash, 10% kaolin, 18% washed fine sand, 5% polyurethane, and 1% high-efficiency water reducer.

[0075] In order to strengthen the connectivity between the polyurethane cement and the low fiber content layer and the medium fiber content layer, short chopped reinforcing fibers can be added to the polyurethane cement, and the volume ratio of the polyurethane cement to the short chopped reinforcing fibers is 100:0.35.

[0076] Wherein, S400 specifically includes the following steps:

[0077] S410: Use a roller with burrs to exhaust the surface of the facing layer, and then smooth the surface with a roller;

[0078] S420: The penetration piece is sequentially passed through the surface layer, the medium fiber content layer and the low fiber content layer until one end of the penetration piece penetrates into the base layer of the area to be repaired, and multiple penetration pieces are arranged in the entire repair area to obtain a short-cut-continuous fiber composite reinforced repair composite material.

[0079] The present invention utilizes the penetration reinforcement effect of the penetration piece. When the medium fiber content layer and the surface layer cement mortar have not yet solidified, the steel needle injected into the repair layer penetrates the low fiber content from the surface layer and even inserts into the base. In this way, on the one hand, it helps to drag the fiber grid during the solidification stage to slow down the sagging tendency of the mixed material caused by gravity, and on the other hand, after hardening, each repair layer can maintain a high bonding force with the base for a long time.

[0080] In order to strengthen the direct connectivity between the penetration piece and each layer and prevent the penetration piece from coming out of the composite material, a layer of the above-mentioned polyurethane cement may be coated on the surface of the penetration piece before using the penetration piece.

[0081] When the repair area is deep, two or more layers of synthetic fiber untwisted yarn three-dimensional fabric can be used for superposition repair. S300 specifically includes the following steps:

[0082] S310: laying a three-dimensional fabric of synthetic fiber untwisted yarn on the medium fiber content layer, and rolling the three-dimensional fabric of synthetic fiber untwisted yarn with a roller until the three-dimensional fabric of synthetic fiber untwisted yarn is pressed into the cement mortar with the medium fiber content, and the cement mortar with the medium fiber content emerges from the three-dimensional fabric of synthetic fiber untwisted yarn, thereby forming a first surface layer tightly connected with the medium fiber content layer;

[0083] S320: laying medium fiber content cement mortar on the first surface layer, and then repeating the step of S310 to form a second surface layer tightly connected to the first surface layer;

[0084] S330: Repeat step S320 0-2 times, and finally obtain multiple surface layers tightly connected to the medium fiber content layer.

[0085] Embodiment 1:

[0086] This embodiment provides a construction method for a chopped-continuous fiber composite reinforced repair composite material, and the specific construction steps include:

[0087] S100: After necessary cleaning, cleaning and roughening operations are performed on the road surface area to be repaired, an interface agent is applied or sprayed. After the interface agent is absorbed by the substrate, low-fiber cement mortar is immediately applied or sprayed, and then manual leveling is performed to form a low-fiber layer;

[0088] S200: before the low-fiber content cement mortar initially sets, the fiber mesh is laid on the surface of the low-fiber content layer, and the edges of the fiber mesh are nailed to the sides of the area to be repaired, and the middle part of the fiber mesh is embedded in the low-fiber content cement mortar; after the low-fiber content cement mortar initially sets, medium-fiber content cement mortar is laid on the fiber mesh to form a medium-fiber content layer;

[0089] S300: laying a synthetic fiber untwisted yarn three-dimensional fabric on the medium fiber content layer, and rolling the synthetic fiber untwisted yarn three-dimensional fabric with a roller until the synthetic fiber untwisted yarn three-dimensional fabric is pressed into the medium fiber content cement mortar, and the medium fiber content cement mortar emerges from the synthetic fiber untwisted yarn three-dimensional fabric, thereby forming a surface layer tightly connected with the medium fiber content layer;

[0090] S400: Use a roller with burrs to exhaust the surface of the surface layer, then smooth the surface with the roller, and use a nail gun to randomly but as evenly as possible shoot steel nails into the repaired area, so that the steel nails vertically penetrate each repair layer. When the entire repair area is hardened, grind off the exposed steel nails on the surface to obtain a short-cut-continuous fiber composite reinforced repair composite material.

[0091] Among them, the low-fiber cement mortar contains: 38% Portland cement, 34% fly ash, 10% kaolin, 18% washed fine sand, 5% rubber powder, and 1% high-efficiency water reducer. The volume ratio of low-fiber cement mortar to chopped reinforcing fiber is 100:0.28.

[0092] The medium fiber content cement mortar contains: 38% silicate cement, 34% fly ash, 5% silica fume, 5% kaolin, 18% washed fine sand, 1% high efficiency water reducer, and the volume ratio of medium fiber content cement mortar to short chopped reinforcing fiber is 100:0.5;

[0093] The three-dimensional fabric of synthetic fiber untwisted yarn is woven from PVA and PE fibers with a thickness of 4mm.

[0094] The repair composite material prepared in this embodiment is as follows Figure 1 As shown, the base 100 is the road surface to be repaired, and then a low fiber content layer 320, a medium fiber content layer 320, and a surface layer 330 are laid in sequence on the base 100, and a fiber grid 340 is also provided on the side of the medium fiber content layer 320 close to the low fiber content layer 320, and a plurality of penetration pieces 200 (that is, steel wire nails in this embodiment) pass through the surface layer 330, the medium fiber content layer 320, and the low fiber content layer 320 and penetrate into the base 100.

[0095] The repair composite material prepared in Example 1 was tested. The test showed that the destructive strength of the composite reinforced repair material was 703 kN.

[0096] The equivalent bending toughness, equivalent bending strength, flexural strength and compressive strength of the repaired composite material after 60 days are tested, and the data are as follows:

[0097]

[0098] The test results show that the repair composite material of the present invention has good equivalent bending toughness, equivalent bending strength, flexural strength, compressive strength, etc. And by testing the internal structure of the repair composite material, it can be found that the short-cut reinforcement fibers in the cement are relatively evenly distributed without agglomeration.

[0099] Embodiment 2:

[0100] This embodiment provides a construction method for a chopped-continuous fiber composite reinforced repair composite material, and the specific construction steps include:

[0101] S100: After necessary cleaning, cleaning and roughening operations are performed on the road surface area to be repaired, an interface agent is applied or sprayed. After the interface agent is absorbed by the substrate, low-fiber cement mortar is immediately applied or sprayed, and then manual leveling is performed to form a low-fiber layer;

[0102] S200: before the low-fiber content cement mortar initially sets, the fiber mesh is laid on the surface of the low-fiber content layer, and the edges of the fiber mesh are nailed to the sides of the area to be repaired, and the middle part of the fiber mesh is embedded in the low-fiber content cement mortar; after the low-fiber content cement mortar initially sets, medium-fiber content cement mortar is laid on the fiber mesh to form a medium-fiber content layer;

[0103] S300: laying a synthetic fiber untwisted yarn three-dimensional fabric on the medium fiber content layer, and rolling the synthetic fiber untwisted yarn three-dimensional fabric with a roller until the synthetic fiber untwisted yarn three-dimensional fabric is pressed into the medium fiber content cement mortar, and the medium fiber content cement mortar emerges from the synthetic fiber untwisted yarn three-dimensional fabric, thereby forming a surface layer tightly connected with the medium fiber content layer;

[0104] S400: Use a roller with burrs to exhaust the surface of the surface layer, then smooth the surface with the roller, and use a nail gun to randomly but as evenly as possible shoot steel nails into the repaired area, so that the steel nails vertically penetrate each repair layer. When the entire repair area is hardened, grind off the exposed steel nails on the surface to obtain a short-cut-continuous fiber composite reinforced repair composite material.

[0105] Among them, the low-fiber cement mortar contains: 38% silicate cement, 34% fly ash, 10% kaolin, 18% washed fine sand, 5% rubber powder, and 1% high-efficiency water reducer. The mass ratio of low-fiber cement mortar to chopped reinforcing fiber is 100:0.09.

[0106] The medium fiber content cement mortar contains: 38% silicate cement, 34% fly ash, 5% silica fume, 5% metakaolin, 18% washed ground sand, 1% high-efficiency water reducer, and the mass ratio of medium fiber content cement mortar to short-cut reinforcing fiber is 100:0.18;

[0107] The three-dimensional fabric of synthetic fiber untwisted yarn is woven from PE and PET fibers with a thickness of 4mm.

[0108] Embodiment three:

[0109] This embodiment provides a construction method for a chopped-continuous fiber composite reinforced repair composite material, and the specific construction steps include:

[0110] S100: After necessary cleaning, cleaning and roughening operations are performed on the road surface area to be repaired, an interface agent is applied or sprayed. After the interface agent is absorbed by the substrate, low-fiber cement mortar is immediately applied or sprayed, and then manual leveling is performed to form a low-fiber layer;

[0111] S200: before the low-fiber content cement mortar initially sets, the fiber mesh is laid on the surface of the low-fiber content layer, and the edges of the fiber mesh are nailed to the sides of the area to be repaired, and the middle part of the fiber mesh is embedded in the low-fiber content cement mortar; after the low-fiber content cement mortar initially sets, medium-fiber content cement mortar is laid on the fiber mesh to form a medium-fiber content layer;

[0112] S300: laying a first layer of synthetic fiber untwisted yarn three-dimensional fabric on the medium fiber content layer, and rolling the first layer of synthetic fiber untwisted yarn three-dimensional fabric with a roller until the first layer of synthetic fiber untwisted yarn three-dimensional fabric is pressed into the medium fiber content cement mortar, and the medium fiber content cement mortar emerges from the first layer of synthetic fiber untwisted yarn three-dimensional fabric, thereby forming a first surface layer tightly connected to the medium fiber content layer;

[0113] Then, a medium-fiber-content cement mortar is laid on the first surface layer, and then a second layer of synthetic fiber untwisted yarn three-dimensional fabric is laid thereon, and a roller is used to roll on the second layer of synthetic fiber untwisted yarn three-dimensional fabric until the second layer of synthetic fiber untwisted yarn three-dimensional fabric is pressed into the medium-fiber-content cement mortar, and the medium-fiber-content cement mortar emerges from the second layer of synthetic fiber untwisted yarn three-dimensional fabric, thereby forming a second surface layer tightly connected to the first surface layer;

[0114] S400: Use a roller with burrs to exhaust the surface of the second surface layer, then smooth the surface with the roller, and use a nail gun to randomly but as evenly as possible shoot steel nails into the repaired area, so that the steel nails vertically penetrate each repair layer. When the entire repair area is hardened, grind off the exposed steel nails to obtain a short-cut-continuous fiber composite reinforced repair composite material.

[0115] Among them, the low-fiber cement mortar contains: 38% Portland cement, 34% fly ash, 10% kaolin, 18% washed fine sand, 5% rubber powder, and 1% high-efficiency water reducer. The volume ratio of low-fiber cement mortar to chopped reinforcing fiber is 100:0.28.

[0116] The medium fiber content cement mortar contains: 38% silicate cement, 34% fly ash, 5% silica fume, 5% kaolin, 18% washed fine sand, 1% high efficiency water reducer, and the volume ratio of medium fiber content cement mortar to short chopped reinforcing fiber is 100:0.5;

[0117] The three-dimensional fabric of synthetic fiber untwisted yarn is woven from PVA and PE fibers with a thickness of 4mm.

[0118] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A chopped-continuous fiber composite reinforced repair composite material, characterized in that: The invention comprises a low fiber content layer, a medium fiber content layer and a surface layer which are arranged in sequence, wherein the low fiber content layer and the medium fiber content layer both contain short-cut reinforcing fibers, wherein the short-cut reinforcing fibers are at least one of PVA fibers and PE fibers, wherein the low fiber content layer contains 0.08%-0.3% of the short-cut reinforcing fibers, and the medium fiber content layer contains 0.15%-0.6% of the short-cut reinforcing fibers, and the surface layer contains a three-dimensional fabric of synthetic fiber untwisted yarn, and the thickness of the three-dimensional fabric of synthetic fiber untwisted yarn is 3mm-5mm; The low-fiber-content cement mortar constituting the low-fiber-content layer contains: 35%-40% of silicate cement, 30%-36% of fly ash, 8%-12% of metakaolin, 15%-20% of washed fine sand, 3%-7% of rubber powder, and 0.5%-1.5% of high-efficiency water reducing agent; The medium fiber content cement mortar constituting the medium fiber content layer contains: 35-40% of silicate cement, 30%-36% of fly ash, 3%-7% of silica fume, 3%-7% of metakaolin, 15%-20% of washed ground sand, and 0.5%-1.5% of high-efficiency water reducing agent.

2. The chopped-continuous fiber composite reinforced repair composite material according to claim 1, characterized in that: The volume ratio of the low-fiber content cement mortar to the chopped reinforcing fibers is 100:(0.2-0.3), or the mass ratio of the low-fiber content cement mortar to the chopped reinforcing fibers is 100:(0.08-0.1), and the compressive strength of the low-fiber content layer reaches 30MPa-50MPa; The volume ratio of the medium fiber content cement mortar to the chopped reinforcing fibers is 100:(0.4-0.6), or the mass ratio of the medium fiber content cement mortar to the chopped reinforcing fibers is 100:(0.15-0.2), and the compressive strength of the medium fiber content layer reaches 60MPa-80MPa.

3. The chopped-continuous fiber composite reinforced repair composite material according to claim 1, characterized in that: A fiber grid is also provided in the medium fiber content layer. The fiber grid has a grid length of 5mm-10mm and a width of 5mm-10mm. The fiber grid is one or more of bidirectional carbon fiber, alkali-resistant glass fiber, basalt fiber, polyvinyl alcohol fiber, high modulus polyethylene fiber, and steel wire grid.

4. The chopped-continuous fiber composite reinforced repair composite material according to claim 1, characterized in that: Also includes: A plurality of penetrations are provided, and the penetrations all pass through the low fiber content layer, the medium fiber content layer, and the surface layer.

5. A construction method for chopped-continuous fiber composite reinforced repair composite material, characterized in that: For laying the chopped-continuous fiber composite reinforced repair composite material according to claim 1, the specific construction steps include: S100: Laying low-fiber cement mortar on the surface of the area to be repaired to form a low-fiber layer; S200: laying medium fiber content cement mortar on the low fiber content layer to form a medium fiber content layer; S300: laying a three-dimensional fabric of synthetic fiber untwisted yarn on the medium fiber content layer, and rolling the three-dimensional fabric of synthetic fiber untwisted yarn with a roller until the three-dimensional fabric of synthetic fiber untwisted yarn is pressed into the medium fiber content cement mortar, and the medium fiber content cement mortar emerges from the three-dimensional fabric of synthetic fiber untwisted yarn, thereby forming a surface layer tightly connected to the medium fiber content layer; S400: performing exhaust treatment on the surface of the surface layer with a roller with burrs, and then smoothing the surface with the roller to obtain the chopped-continuous fiber composite reinforced repair composite material.

6. The construction method according to claim 5, characterized in that: In S100, before laying the low-fiber cement mortar, the area to be repaired is cleaned and roughened, and an interface agent is coated or sprayed on the surface of the area to be repaired; after laying the low-fiber cement mortar, the low-fiber cement mortar is leveled to form the low-fiber layer.

7. The construction method according to claim 5, characterized in that: The S200 specifically includes the following steps: S210: before the low-fiber content cement mortar initially sets, laying a fiber grid on the surface of the low-fiber content layer, nailing the edge of the fiber grid to the side of the area to be repaired, and embedding the middle part of the fiber grid into the low-fiber content cement mortar; S220: After the low-fiber content cement mortar is initially set, medium-fiber content cement mortar is laid on the fiber grid to form the medium-fiber content layer.

8. The construction method according to claim 5, characterized in that: The S400 specifically includes the following steps: S410: performing exhaust treatment on the surface of the surface layer using a roller with burrs, and then smoothing the surface with the roller; S420: The penetration piece is sequentially passed through the surface layer, the medium fiber content layer and the low fiber content layer until one end of the penetration piece penetrates into the base layer of the area to be repaired, and a plurality of the penetration pieces are arranged in the entire repair area to obtain the chopped-continuous fiber composite reinforced repair composite material.

9. The construction method according to any one of claims 5 to 8, characterized in that: The S300 specifically includes the following steps: S310: laying the synthetic fiber untwisted yarn three-dimensional fabric on the medium fiber content layer, and rolling the synthetic fiber untwisted yarn three-dimensional fabric with a roller until the synthetic fiber untwisted yarn three-dimensional fabric is pressed into the medium fiber content cement mortar, and the medium fiber content cement mortar emerges from the synthetic fiber untwisted yarn three-dimensional fabric, thereby forming a first surface layer tightly connected to the medium fiber content layer; S320: laying the medium fiber content cement mortar on the first surface layer, and then repeating the step of S310, so as to form a second surface layer tightly connected to the first surface layer; S330: Repeat the step of S320 0-2 times, and finally obtain a plurality of surface layers tightly connected to the medium fiber content layer.

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