Claims:CLAIMS:
We Claim:
1. A crystalline admixture and silica fume self-repairing concrete, comprising:
a predetermined amount of concrete, fiber and water being mixed together, wherein each of said fiber has a size about 10-500 microns ,wherein a mass ratio of said concrete, crystalline admixture, and water is 100:1-15:15-50, wherein when said capsule wall of one of said fiber is cracked, said adhesive is released from said crystalline admixture for flowing to a fracture surface of said concrete structure so as to repair said fracture surface thereof.
2. The self-repairing concrete, as recited in claim 1, wherein a mass ratio of said capsule wall and said adhesive is 100:40-80, wherein a thickness of said capsule wall is about 1-10 microns.
3. The self-repairing concrete, as recited in claim 2, wherein each of said fiber has a spherical shape with a diameter about 10-500 microns.
4. The self-repairing concrete, as recited in claim 3, wherein said adhesive is a mono-component adhesive selected from the group consisting of mono-component polyurethane adhesives, organosilico anaerobe, acrylic resin adhesives, chloroprene rubber adhesives, and multi-component epoxy adhesives.
5. The self-repairing concrete, as recited in claim 4, wherein said multi-component epoxy adhesive consists of one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, resorcinol epoxy resin, silicone modified bisphenol A epoxy resin or organic titanium modified bisphenol A epoxy resin.
6. The self-repairing concrete, as recited in claim 5, wherein said fiber are pre-mixed with 0.1-0.5% hydrophilic surfactant by weight based on the weight of said fiber and are uniformly distributed in said concrete, wherein said hydrophilic surfactant comprises one or more of sodium alkylbenzenesulfonate, polyoxyethylene, poly-glycide compound or polyol.
7. The self-repairing concrete, as recited in claim 6, wherein each of said fiber further comprises 8-25% diluent by weight based on the weight of said crystalline admixture, said diluent comprising a curing agent chemically reacting with epoxy resin and improving liquidity of said epoxy resin.
8. The self-repairing concrete, as recited in claim 7, wherein said curing agent, which is a middle-low temperature reaction curing agent, comprises one or more of linear chain aliphatic polyamine, polyamide, aromatic amine, modified polyamine, polythiol, carbamide derivative, iminazole derivative, wherein a mass ratio of said curing agent and said epoxy resin is about 12-35%.
9. The self-repairing concrete, as recited in claim 2, wherein said adhesive is a mono-component adhesive selected from the group consisting of mono-component polyurethane adhesives, organosilico anaerobe, acrylic resin adhesives, chloroprene rubber adhesives, and multi-component epoxy adhesives.
10. The self-repairing concrete, as recited in claim 9, wherein said multi-component epoxy adhesive consists of one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, resorcinol epoxy resin, silicone modified bisphenol A epoxy resin or organic titanium modified bisphenol A epoxy resin. , Description:DESCRIPTION:
Field of the invention:
[0001] This invention relates to self-repairing concrete and similar building materials, particularly relates to self-repairing concrete, similar building materials, and methods of process.
Background of the invention:
[0002] As a representative of the traditional building materials, concrete takes advantages of high compressive strength, high durability and low cost, widely used in industrial and civil buildings, bridges, road projects, underground projects, water conservancy and hydropower projects, nuclear power plants, ports and marine engineering etc. Currently, concrete has more than 100 years of history from it been invented, which penetrates to large-span structures, high-rise structures, mega-structure and the special structure.

[0003] The foreseeable future, during the country's modernization construction, concrete is still an indispensable building materials. Due to the use of long-term process and under the influence of the surrounding complex environment, in-service concrete structures is producing micro-cracking and local damage inevitably, which would reduce the life of the structures lightly, or would threaten structures safety. For raw materials, mixing ratio, additives, manufacturing processes, casting processes methods, and conservation area will be reviewed and improved, these methods didn't fundamentally change the performance of concrete weaknesses. Therefore, to repair the crack of the concrete in service timely and effectively has become a major concern of scientists and engineers. Due to earthquakes, wind loads, shock and other causes of damage, can visually detect and fix it manually, using traditional methods (program repair and post-restoration) on the crack repair. In the actual structure of concrete works, there are many small cracks, such as matrix micro-cracking etc, these micro-scale damages due to the limitations of detection technologies may be undetectable.

[0004] Therefore, it becomes very difficult to repair these undetectable cracks and damages, if not impossible. If the cracks or damages cannot be timely and effectively restoration, the structure will not only affect the normal use of the performance and shorten the life, but also macro-cracks may be triggered and led to structural brittle fracture, resulting in serious catastrophic accidents. There is an urgent need to adopt a certain technology or method, can take the initiative to automatically part of the crack and damage repairing, restore or even increase the strength of concrete materials in order to achieve the purpose of extending the service life of concrete structures. Existing technologies cannot improve the solution of concrete micro-cracks self-diagnosing and self-repairing the problems. The self-repairing of the concrete is conducted by adding special components (such like shape memory alloy) to form intelligent self-repairing system that can be automatically triggered to fix the damage or crack of the concrete material.
Summary of the invention:
[0005] The present disclosure proposes a self-repairing concrete used crystalline admixture and silica fume. The following presents a simplified summary in order to provide a basic understanding of some aspects of the claimed subject matter. This summary is not an extensive overview. It is not intended to identify key/critical elements or to delineate the scope of the claimed subject matter. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later.

[0006] It is an object of the present invention to provide a self-repairing concrete having crystalline admixture and silica fumethat can effectively achieve self-repairing of the micro cracks of the concrete. Through appropriate distribution ratio of components, and process conditions etc., form a polymer fiber self-repairing concrete structures.

[0007] The invention's technical program is a used crystalline admixture and silica fumeself-repairing concrete, wherein said concrete mixed polymer fiber with repairing concrete function, said concrete mass ratio is concrete: fiber: water=100:1-15:15-50.

[0008] A preferred program is wherein said fiber including adhesives, fiber wall packed said adhesives made of crystalline admixture. Said urea-formaldehyde resin polymer including Melamine-formaldehyde, urea-melamine-formaldehyde, are also described in the application of this invention self-healing concrete material and methods.

[0009] A preferred program is wherein said fiber wall polymers and capsule-core mass ratio is 100:40-80, the fiber Shaped like spherical, granules diameter is 10-500 µm, wall thickness is 1-10 µm.

[0010] A preferred program is said adhesives are mono-component adhesives, comprising: mono-component polyurethane adhesives, organosilico anaerobe, acrylic resin adhesives and chloroprene rubber adhesives, or multi-component epoxy adhesives; said adhesives having excellent fluidity and cohesion strength.

[0011] A preferred program is said multi-component epoxy adhesives, comprising one or more: bisphenols an epoxy resin, bisphenols F epoxy resin, bisphenols S epoxy resin, resorcinol epoxy resin, organosilicon modified bisphenols A epoxy resin or organotitanium modified bisphenols A epoxy resin.

[0012] A preferred program is said fibers premixed hydrophilc surfactant 0.1-5%, said hydrophilc surfactant uniform distributed in said concrete; said hydrophilc surfactant comprising one or more: sodium alkylbenzenesulfonate, polyoxyethylene, polyglycide or polyol.

[0013] A preferred program is said curing agent is middle-low temperature reaction curing agent, comprising one or more linear chain aliphatic polyamine, polyamide, aromatic amine, modified polyamine, polythiol, carbamide derivative, iminazole derivative; said curing agent and epoxy resin mass ratio is 12-35%.

[0014] Another technical program of the invention solve the existing concrete micro-cracks of the self-diagnosis and self-repairing technical problems is providing a method of processing using crystalline admixtureself-repairing concrete.

[0015] A preferred program is a method of processing using crystalline admixturefibers self-repairing concrete, comprising:
(1) Weighting enough water, mixing appreciable proportion crystalline admixturefibers, stirring gently, still to fibers well-diversified;
(2) Put water into concrete stirred vessel, mixing corresponding quality concrete;
(3) Stirring concrete slurry slowly, and then stirring concrete slurry rapidly;
(4) Mixing filling agent, comprising dinas, field poured, meaning to put into concrete slurry as three times, each time one third, vibrating, trouble-shooting of bubbles; still filling with mould.

[0016] Another technical program of the invention solve the existing concrete micro-cracks of the self-diagnosis and self-repairing technical problems is providing a method of processing using crystalline admixturefibers self-repairing concrete. Through appropriate distribution ratio of components, and process conditions etc, form a polymer fiberself-repairing concrete structures and its surface and internal features, to ensure the representativeness of the sample, in order to better evaluate the integrity of the structure of self-repairing concrete.

[0017] A preferred program is using crystalline admixturefibers self-repairing concrete, wherein comprising:
(1) Weighting enough water, mixing appreciable proportion crystalline admixturefibers, stirring gently, still to fibers well-diversified;
(2) Put water into concrete stirred vessel, mixing corresponding quality concrete;
(3) Stirring concrete slurry slowly, and then stirring concrete slurry rapidly;
(4) Vibrated concrete slurry, progressively or step by step watering workpiece.
(5) Stewing one or two hours, and then stripping, strike off overflow concrete slurry of mould, stewing 21 to 26 hours;
(6) After disassembly the mould, transferring workpiece to concrete incubator, incubating 25 to 31 days.

[0018] The invention providing a method of processing using crystalline admixture and silica fumeself-repairing concrete. Through the control of surface properties of fiber, making fiber and concrete to form a good interface. Through appropriate distribution ratio of components, and process conditions etc, form a polymer fiberself-repairing concrete structures and its surface and internal features, to ensure the representativeness.

[0019] The invention using diluents, curing agent and epoxy resin, form a good fluidity, curing high-strength polymer, bonding the crack surface effectively, to the purpose of restore the mechanical properties and the usage.

[0020] The invention using the fiber materials, which has good dispersion and stability, through a typical production process of concrete, fiberare evenly dispersed in the matrix of concrete, in the process of mixing and the conservation, crystalline admixture material fragmentation does not occur. In the crack process, fiber release adhesives under the stress, repairing the concrete.

[0021] In one aspect, the invention provides a class of epoxy adhesives used in concrete materials self-repairing, comprising epoxy resin 100, diluent10-30, curing agent15-35.

[0022] Adding epoxy diluents which can reduce the viscosity of the material and increase liquidity. The modified epoxy resin used polymer material parcels. Curing agent can be used directly or be used after micro-encapsulation.

[0023] In another aspect, the invention provides methods for preparing self-healing of concrete repairing agent fiber. Prepared by chemical self-healing of concrete composite materials used in fiber technology, wrapped up repair agents such as epoxy resin to form a sealed envelope. The advantages lie in the formation of fiber, the capsule core is isolated from the outside environment, making it from the outside temperature, oxygen and ultraviolet light and other factors, in appropriate conditions, and capsule core can be released after envelope is broken. Used for self-healing of fiber must have the appropriate mechanical strength and heat resistance, active capsule core material should have low viscosity, the expansion coefficient is small after reaction, high performance of adhesive strength, thus, it not only ensure composite molding maintain the integrity of the process, but also in the micro-crack front-end break under stress or heat release capsule core. These methods are:

[0024] In another aspect, the invention provides a good dispersion of crystalline admixture and silica fume material, which can be used manufacture self-healing of concrete materials, comprising Polymer fiber: 100, Surfactant: 0.5-5.

[0025] Mixing surfactant in polymer fiber material, using mixing equipment for mixing. During the self-repairing concrete material preparation process, the crystalline admixture material reunion does not occur, and distributed evenly in the concrete structure.

[0026] After typical experiments of concrete process and cracks, manufacture self-repairing concrete materials. In the self-repairing concrete materials, the crack stress makes the fiber rupture, released capsule core was siphon through the micro-cracks capillary, which flow to the crack surface, occurring polymerization reacting with the curing agent, forming a high strength polymers material repairing crack face, so as to achieve the purpose of repair material. Compared with material starting state and the destruction of the state, the mechanical properties of significant recovery, especially the bending strength.

[0027] In another aspect, the invention provides methods for preparing self-healing of concrete repairing agent fiber. For the ratio of concrete which includes the organic fiber containing, using the following process can produce evenly dispersion and stability of fiberself-repairing concrete materials, would be not occur fragmentation during mixing and conservation.
(1) Weighting enough water, mixing appreciable proportion crystalline admixturefiber, stirring gently, still to fiber well-diversified;
(2) Put water into concrete stirred vessel, mixing corresponding quality concrete;
(3) Stirring concrete slurry slowly, and then stirring concrete slurry rapidly;
(4) Vibrated concrete slurry, progressively or step by step watering workpiece.
(5) Stewing one hour, and then stripping, strikes off overflow concrete slurry of mould, stewing 24 hours;
(6) After disassembly the mould, transferring workpiece to concrete incubator, incubating 28 days.

[0028] Step (3) of the invention described using of organic materials crystalline admixture repair concrete structure manufacturing method, the mixing is to first slow stirring (100-300 rpm), and changed to the rapid mixing (700-1000 rpm).

[0029] Step (4) of the invention described using of organic materials crystalline admixture repair concrete structure manufacturing method, Vibrated concrete slurry, trouble-shooting of bubbles; still filling with mould, step by step.

[0030] Step (4) of the invention described using of organic materials fiber repair concrete structure manufacturing method, field poured, meaning to put into concrete slurry as three times, each time one third, vibrating, trouble-shooting of bubbles; still filling with mould.

[0031] The beneficial effect of this invention is containcrystalline admixture of concrete materials experienced 8 MPa pre-damage and curing treatment, compared with the corresponding concrete material; its flexural strength was unchanged or increased. After the same conditions of concrete materials, flexural strength decreased significantly. These data show that fiber materials during the damage process, epoxy resin was released, reacted with curing agent in the micro-cracks, repaired of damaged structures, achieved to self-repairing concrete materials capabilities. Therefore, the use of fiber can be made self-healing concrete materials, to achieve self-diagnose and repair micro-cracks in concrete, preventing micro-cracks expanded, maintaining the mechanical structure of the building, having great economic value and environmental value.

[0032] Further, objects and advantages of the present invention will be apparent from a study of the following portion of the specification, the claims, and the attached drawings.
Detailed description of drawings:
[0033] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention, and, together with the description, explain the principles of the invention.

[0034] FIG. 1 shows the invention using of crystalline admixture and silica fumeself-repairing concrete.

[0035] FIG. 2 shows the fracture morphology of self-repairing concrete composite materials.

[0036] FIG. 3 shows the concrete interface of self-repairing concrete composite materials.

[0037] FIG. 4 shows the didn't were broken during concrete manufacturing process.
Detailed invention disclosure:
[0038] Various embodiments of the present invention will be described in reference to the accompanying drawings. Wherever possible, same or similar reference numerals are used in the drawings and the description to refer to the same or like parts or steps.

[0039] Embodiment 1

[0040] Using diluents to improve the fluidity of epoxy resin and adhesive performance, increasing repair efficiency of self-repairing concrete composite materials. adding 20% of the 17 alkyl imidazole curing agent in the E-51 epoxy adhesive, and then adding 20% N-butyl glycidyl ether, the viscosity from the 8200 mpa•s down to 200 MPa•s, the epoxy adhesive fluidity is increasing, which took advantages of capillary siphon; tensile strength varied from 14.0 MPa to 17.6 MPa, modulus from 223.3 MPa increase to 334.0 MPa, which proved that N-butyl ether improve the mechanical properties of epoxy resin. FTIR analyzed showing that the diluents involved in the epoxy adhesive and curing agent cross-linking reaction.

[0041] Embodiment 2

[0042] With crystalline admixture as an envelope, put capsule core materials such as repair agents epoxy resin wrapped, preparation for self-repairing concrete composite material fibers. Dissolved 10.0 grams urea in 20.0 grams 37% formaldehyde, using triethanolamine adjusted pH to 8.5, in mixing state and 70° C. constant temperature conditions, reacted 1 hour, obtained prepolymer. Added 80-160 ml distilled water, add 14.0 grams epoxy resin of example 1 said, a strong stirring for 20 minutes, got a better stability of the oil/water emulsion. Within 2 hours, with 2% sulfuric acid adjusts pH to 4-5. In the stirring speed 300-1200 rpm, reaction temperature 50-80° C. conditions, reacted 2-3 hours. Product was cooled, washed by distilled water, dried and other steps got a white crystalline admixture material. The fibershowed spherical, with an average particle diameter of 120 microns, wall thickness of 3.5 microns, electron microscope photographs shown in FIG. 1.

[0043] Embodiment 3

[0044] Using surfactant to improve the manufacture of concrete self-repairing polymer materials fibers fluidity and dispersion. Mixed 1.5 grams sodium dodecyl benzene sulfonate the invention said in 100 grams of polymer fiber of epoxy resin material, and then stirring for 30 minutes, got a good fluidity and dispersion powder-like substance.

[0045] Embodiment 4

[0046] Using crystalline admixture material for preparing self-repairing concrete samples. Weight 38.0 grams of water, add 2.0 grams of fiber to said water, stirring till fibers fully dispersed; pouring water into the concrete mixing container, mixed 100.0 grams concrete; stirring, vibrating, and watering the workpiece etc; Stewed one hour, and then stripping, scraped mold overflow of concrete slurry, Stewed 24 hours; After disassembly the mould, transferring workpiece to concrete incubator, incubating 28 days.

[0047] Flexural strength testing and fracture morphology for self-repairing concrete. In the fracture process, most of organic crystalline admixture destruction under the stress, a small portion appearance organic fiber/concrete interface separation, shown in FIG. 2. Organic fiber and concrete can be formed a good interface, shown in FIG. 3. Testing mechanical properties using three-point bending method, the sample size was 4 cm×4 cm×16 cm, imposed 8 MPa generated pre-cracks. Flexural strength of concrete materials was 11.3 MPa. After the designed destruction pressure, flexural strength of concrete decreased to 5.5 MPa. The organic fiber concrete composite material through the designed destruction pressure and heat repair process, the flexural strength of 11.15 MPa, through the same pressure damage and repair processes at room temperature, flexural strength was 10.0 MPa. These figures showed that: concrete composite materials used organic fiber, compared with material starting state and the destructed state, bending strength was little change or increase, mechanical properties was significant recovery, proved that the organic fiber had functions for the concrete structure micro-cracks repair. In the self-repairing concrete materials, the crack stress makes the fiber rupture, released capsule core was siphon through the micro-cracks capillary, which flow to the crack surface, occurring polymerization reacting with the curing agent, forming a high strength polymers material repairing crack face, so as to achieve the purpose of repairing material.

[0048] Embodiment 5

[0049] Using urea-melamine-formaldehyde polymer fiber material for preparing self-repairing concrete. Weight 38.0 grams of water, add 5.0 grams of fiber to said water, stirring till fibers fully dispersed; pouring water into the concrete mixing container, mixed 60.0 grams concrete, 20.0 grams of sandstone, 10 grams of phosphorous slag powder and 10 grams of fly ash and other materials; stirring, vibrating, and watering the workpiece etc; Stewed one hour, and then stripping, scraped mold overflow of concrete slurry, Stewed 24 hours; After disassembly the mould, transferring workpiece to concrete incubator, incubating 28 days.

[0050] Embodiment 6

[0051] Methods for preparing self-healing of concrete using melamine-formaldehyde polymer fiber, which can produce evenly dispersion and stability of fiberself-repairing concrete materials.
(1) Weighting enough water, mixing appreciable proportion crystalline admixturefiber, stirring gently, still to fiber well-diversified;
(2) Put water into concrete stirred vessel, mixing corresponding quality concrete;
(3) Stirring concrete slurry slowly (300 rpm), and then stirring concrete slurry rapidly (800 rpm);
(4) Vibrated concrete slurry, step by step watering workpiece, field poured, meaning to put into concrete slurry as three times, each time one third, vibrating, trouble-shooting of bubbles; still filling with mould.
(5) Stewing one hour, and then stripping, strikes off overflow concrete slurry of mould, stewing 24 hours;
(6) After disassembly the mould, transferring workpiece to concrete incubator, incubating 28 days.

[0052] Take a sample from said concrete, using 5% sulfuric acid corroded 5 minutes, rinse with distilled water. Dried, electron microscopy observed, shown as FIG. 4. During the concrete material prepared by mixing, curing and maintenance process, used fiber didn't was broken. This phenomenon indicated that use polymer crystalline admixture technology to prepare self-healing process concrete material has good operability, self-repairing properties repeatability and the industrial applications.

[0053] It will readily be apparent that numerous modifications and alterations can be made to the processes described in the foregoing examples without departing from the principles underlying the invention, and all such modifications and alterations are intended to be embraced by this application.