CN116535176A - A kind of material for repairing cracks in concrete pavement and its preparation method - Google Patents

Abstract

A material for repairing concrete pavement cracks and a preparation method thereof, the invention belongs to the field of building materials, in particular to a material for repairing concrete pavement cracks and a preparation method thereof. The purpose of the present invention is to solve the problem that the bonding force between the existing joint filling material and the original concrete is insufficient, it is easy to fall off or crack again, and the traffic is affected. A material for repairing cracks on concrete pavement, which consists of 30% to 50% of alkali slag, 10% to 15% of silica fume, 10% to 40% of recycled fine sand, and 5% to 15% of sulfur according to the mass fraction The calcium aluminate expansion agent is composed of 10% to 25% of water. Methods: 1. Prepare alkali stimulator; 2. Prepare alkali slag; 3. Weigh and mix uniformly. The invention is easy to operate and fast in construction, and is suitable for repairing cracks of various widths and depths; the method provided by the invention only needs to mix dry mixture and water according to a certain ratio and pour them into the cracks to complete the repair work.

Description

A kind of material for repairing cracks in concrete pavement and its preparation method

technical field

The invention belongs to the field of building materials, and in particular relates to a material for repairing cracks on concrete pavement and a preparation method thereof.

Background technique

Concrete pavement is a widely used road structure, which has the advantages of high strength, good durability and low maintenance cost. However, due to environmental factors, traffic load, construction quality and other reasons, concrete pavement will inevitably have cracks and other diseases, which will affect the service life and safety of the pavement. Therefore, timely and effective repair of concrete pavement cracks is an important measure to ensure the smooth flow of the road and prolong the life of the pavement.

At present, the commonly used concrete pavement crack repair methods include filling method, cutting method, replacement method and so on. The joint filling method is to pour specific joint filling materials into the cracks to combine with the original concrete to restore or improve the strength and integrity of the pavement. The cutting method is to cut the concrete around the crack into a regular shape, and then fill it with new concrete or other materials. The replacement method involves removing all the concrete from the entire cracked area and replacing it with new concrete or other material.

These methods have their own advantages and disadvantages. The joint filling method is easy to operate, low in cost, and fast in construction speed, but it has certain requirements on the width and shape of the crack, and the bonding force between the joint filling material and the original concrete is insufficient, and it is easy to fall off or reappear. cracking. The cutting method and replacement method can completely solve the crack problem, but the operation is complicated, the cost is high, the construction time is long, and it has a great impact on traffic.

Therefore, there is still a need for a material that can quickly and effectively repair cracks in the concrete pavement, and can form a firm bond with the original concrete without affecting traffic, and a preparation method thereof.

Contents of the invention

The purpose of the present invention is to solve the problem of insufficient bonding force between the existing filling material and the original concrete, easy to fall off or crack again, and affect traffic, and provide a material for repairing concrete pavement cracks and its preparation method.

A material for repairing cracks on concrete pavement, which consists of 30% to 50% of alkali slag, 10% to 15% of silica fume, 10% to 40% of recycled fine sand, and 5% to 15% of sulfur according to the mass fraction The calcium aluminate expansion agent is composed of 10% to 25% of water.

A kind of preparation method of the material that is used for concrete pavement crack repair, it is to carry out according to the following steps:

1. Dissolve NaOH and naphthalene-based water reducer in potassium silicate with a modulus of 0.8-1.4 to obtain an alkali activator;

The mass ratio of NaOH and potassium water glass described in step 1 is 0.2479:1, and the mass ratio of naphthalene-based water reducer and potassium water glass is (0.45～0.77):1;

2. Mix industrial waste slag or quasi-slag powder with alkali activator to obtain alkali slag;

The mass ratio of industrial waste slag or class slag powder and alkali activator described in step 2 is 5.37:1;

3. Weigh 30% to 50% of alkali slag, 10% to 15% of silica fume, 10% to 40% of recycled fine sand, 5% to 15% of calcium sulfoaluminate expansion agent and 10% ~25% water, mixed evenly, to obtain the material for repairing cracks in concrete pavement.

Principle of the present invention:

The present invention utilizes 30% to 50% of alkali slag, 10% to 15% of silica fume, 10% to 40% of recycled fine sand, 5% to 15% of calcium sulfoaluminate expansion agent and 10% to 25% of Water prepares materials for concrete pavement crack repair, and these ingredients improve the overall performance of materials for concrete pavement crack repair through synergistic effects. The following is a brief analysis of the synergy between these materials:

Slag and silica fume: Both slag and silica fume have latent cementitious properties, and when mixed with water, they form a cohesive, gel-like substance that contributes to the compressive strength and rate of hardening of concrete , in addition, the synergy between slag and silica fume can increase the density and impermeability of the material;

Regenerated fine sand: Regenerated fine sand is used as aggregate, which helps to improve the compactness and compressive strength of concrete, and its synergistic effect with slag and silica fume forms a uniform and tight aggregate distribution, thereby improving the overall concrete performance;

Calcium sulfoaluminate expansion agent: The role of calcium sulfoaluminate expansion agent is to cause concrete volume expansion, which offsets the shrinkage characteristics of other materials, thereby reducing concrete shrinkage and cracks. In addition, calcium sulfoaluminate expansion agent also Helps to fill cracks and improve the adhesion of repair materials;

Naphthalene-based water reducer: Naphthalene-based water reducer is an efficient dispersant that can reduce the amount of cement in concrete, and it works synergistically with other ingredients to improve the workability and fluidity of concrete, which makes repairing materials easier to construct , to ensure better filling and sealing of cracks;

Water: Water is a key component of concrete and helps to mix and activate other ingredients. Water works synergistically with other materials to ensure the uniformity and fluidity of concrete. In addition, water also participates in hydration reactions, forming with slag and silica fume Stable cementitious substances, thereby enhancing the compressive strength and durability of the material;

In summary, the synergistic effect between these components makes this concrete pavement crack repairing material have excellent compressive strength, durability, compactness and construction performance, making it an ideal material for pavement crack repairing.

The present invention has the following advantages:

(1), the present invention utilizes slag, silica fume, regenerated fine sand and other industrial waste residues and waste materials to save resources, reduce costs and protect the environment; these waste residues and waste materials are difficult to handle and utilize in general, if directly discharged or filled Buried, it will occupy land resources, pollute the environment, and cause waste; and using them as a component of cementitious materials can not only improve the performance of cementitious materials, but also reduce the demand for fresh raw materials, save energy consumption, and reduce the cost of repair projects. Cost, but also in line with the concept of circular economy and green building;

(2), the present invention utilizes the micro-expansion effect that calcium sulfoaluminate expansion agent produces, strengthens the bonding force of wet mixture and crack wall, improves repair strength and durability; Calcium sulfoaluminate expansion agent is a kind of inorganic gelling agent material, it will produce a small amount of expansion during the hydration process, so that the wet mixture can better fit the crack wall, form a tight interface transition zone, and improve the bonding strength between the prosthesis and the matrix. At the same time, due to the expansion agent The addition of it also increases the volume stability of the wet mixture, reduces the occurrence of dry shrinkage cracks, and prolongs the service life of the prosthetic body;

(3) The present invention is easy to operate and fast in construction, and is suitable for repairing cracks of various widths and depths; the method provided by the present invention only needs to mix the dry mixture and water in a certain proportion and then pour it into the cracks to complete The repair work does not require complicated equipment and tools, and the operation is convenient and quick; due to the good fluidity and filling properties of the wet mixture, it can be poured into cracks of various widths and depths, and can be quickly solidified and hardened, and can be recovered in a short time pavement use function; therefore, the present invention is applicable to concrete crack repair work of various types and scales;

(4), the present invention utilizes the fine particles and high activity of silica fume to improve the compactness and strength of the wet mixture; silica fume is a kind of industrial waste slag produced after coal combustion, and it has extremely fine particles (average particle diameter About 10 microns) and high activity (contains a large amount of glassy silica); silica fume is used as a component of the cementitious material, which can fill the microscopic pores in the wet mixture and improve the compactness and impermeability of the wet mixture ; At the same time, silica fume can also undergo secondary hydration reaction with calcium ions in cement hydration products to generate more hydrated calcium silicate gel, which improves the strength and durability of the wet mixture;

(5), the present invention utilizes the rough surface and porous structure of the regenerated fine sand to increase the cohesion and adhesion of the wet mix; The recycled aggregate obtained after processing, sieving, washing, etc. has a rough surface and a porous structure. Using regenerated fine sand as a component of cementitious material can increase the cohesion in the wet mixture and prevent the loss and settlement of the wet mixture; at the same time, the regenerated fine sand can also increase the adhesion between the wet mixture and the crack wall, Improve the bonding strength between the prosthesis and the matrix.

Description of drawings

Fig. 1 is the mechanical performance test piece of embodiment 1, (a) figure is prismatic bending resistance, compressive test piece, (b) figure is dumbbell-shaped tensile test piece;

Fig. 2 is the damage figure of the mechanical performance test piece of embodiment 1, (a) figure is the fracture resistance figure, (b) figure is the compressive damage figure, (c) figure is the tensile damage figure;

Fig. 3 is the bonding performance test piece of embodiment 1, (a) figure is the prismatic bonded flexural test piece, (b) figure is the dumbbell-shaped bonded tensile test piece;

Fig. 4 is the failure diagram of the adhesive performance test piece of Example 1, (a) is the fracture diagram of the bonding resistance, and (b) is the diagram of the tensile failure of the adhesion.

Detailed ways

Embodiment 1: In this embodiment, a material for repairing cracks on concrete pavement consists of 30% to 50% of alkali slag, 10% to 15% of silica fume, and 10% to 40% of regenerated fine sand according to the mass fraction. , 5% to 15% calcium sulfoaluminate expansion agent and 10% to 25% water.

The silica fume described in this embodiment is obtained by collecting and drying dust discharged from thermal power _plants or _cement plants; the dust refers to fine particles containing oxides such as _SiO2 , _Al2O3 , _Fe2O3 Particles; for example: fly ash, cement kiln dust, etc.; the silica fume can react with alkali activators to generate hydration products with high strength, high durability, high impermeability and high crack resistance, such as CSH condensate glue, NASH gel, etc.

The regenerated fine sand described in this embodiment is a mixture of any one or two or more of waste bricks and tiles, waste concrete, waste mortar, and waste stones that have been pulverized into fine particles; the diameter of the regenerated fine sand is 0.3mm~ 1mm. The regenerated fine sand can recycle construction waste and realize resource recycling, and can be used as the aggregate of the material to provide a skeleton structure of the material and increase the compactness and stability of the material.

The calcium sulfoaluminate expansion agent described in this embodiment is obtained by mixing calcium sulfoaluminate and cement in a certain proportion. The calcium sulfoaluminate refers to an inorganic salt compound having expansion properties and early strength properties. For example: calcium trisulfoaluminate, calcium tetrasulfoaluminate, etc. The cement refers to an inorganic gelling material with coagulation and hardening properties. For example: Portland cement, slag cement, pozzolan cement, etc. The calcium sulfoaluminate and cement are mixed in a mass ratio of 1:2 to 2:1. The calcium sulfoaluminate expansion agent can generate a certain expansion stress during the hydration process, so that the material can fully fill the cracks and form a firm bond with the original concrete, and can also improve the early strength of the material and shorten the construction time.

Mechanical performance is the most basic mechanical performance index of the present invention as a road crack repair material. In the research process, the present invention has studied the tensile and compressive properties of single-doped silica fume, double-doped regenerated fine sand and adding calcium sulfoaluminate expansion agent. , flexural properties were systematically studied and compared, and the best results were obtained. The 28-day tensile strength can reach 2MPa-2.5MPa, the compressive strength can reach 70MPa-90MPa, and the flexural strength can reach 6MPa-10MPa.

Fluidity refers to the ability of repairing materials to smoothly enter and fill cracks during construction, and is an important indicator for evaluating the construction performance of repairing materials. Too low flow will cause the repair material to fail to fill the cracks completely, forming voids or honeycombs, reducing the bond strength and impermeability to the base layer; too high flow will cause the repair material to settle or lose after construction, resulting in uneven surfaces or loss to waste. According to previous studies, the present invention regards a fluidity of 200mm-300mm as the criterion for effectively filling cracks in concrete pavement.

Early strength refers to reaching a certain strength and durability in a relatively short period of time to meet the requirements of resuming traffic as soon as possible. Early strength not only affects repair efficiency and cost, but also affects repair effect and life. If the early strength of the repair material is insufficient, it will lead to deformation, cracking or falling off of the repaired area under the action of traffic load, which will reduce the repair quality and benefit. As a concrete pavement crack repairing material, the invention has an initial setting time of 7 minutes to 10 minutes and a final setting time of 20 minutes to 30 minutes, which can meet the requirement of fast repairing of concrete road surface cracks.

The durability of repairing materials is the key to ensuring road quality and prolonging the service life. Studying the durability of repairing materials can improve road safety and comfort, avoid accidents and noise caused by crack expansion, and reduce road maintenance costs and frequency. Save resources and manpower; prolong road life, reduce waste and environmental pollution; promote the development and application of new repair materials, and promote road technology innovation. In the process of durability research, the present invention focuses on the freeze-thaw resistance and chloride ion corrosion resistance of materials to verify the impact of extreme environments such as temperature changes in northern winter and snowmelt spraying on the repairing effect of repairing materials.

Bonding performance is the key to crack repairing materials being able to effectively repair cracks. When studying the bonding performance of the material and the original cement-based material of the concrete road, the present invention designs a bonded flexural test and a bonded tensile test of the two materials. research. It is recommended that the bonded flexural strength should reach 1.5MPa-2MPa in 3 days, and the bonded tensile strength should reach 0.5MPa-1MPa in 3 days.

Embodiment 2: The difference between this embodiment and Embodiment 1 is that the alkali slag is obtained after the industrial waste slag or slag-like powder is excited by an alkali activator, wherein the industrial waste slag or slag-like powder and the alkali activator The mass ratio is 5.37:1. Other steps are the same as in the first embodiment.

The industrial waste slag or slag-like powder mentioned in this embodiment refers to waste or man-made substances containing oxides such as SiO ₂ , CaO, Al ₂ O ₃ . For example: blast furnace slag, converter slag, electric furnace slag, metallurgical dust, cement kiln dust, etc.

Embodiment 3: The difference between this embodiment and Embodiment 1 or 2 is that the alkali activator is prepared by dissolving NaOH and naphthalene-based water reducer in potassium water glass with a modulus of 0.8-1.4 Obtained, wherein the mass ratio of NaOH to potassium water glass is 0.2479:1, and the mass ratio of naphthalene-based water reducer to potassium water glass is (0.45-0.77):1. Other steps are the same as those in Embodiment 1 or 2.

The modulus described in this embodiment refers to the mass ratio of SiO ₂ to K ₂ O in potassium silicate. The larger the modulus, the higher the content of SiO ₂ and the lower the alkalinity of the potassium silicate glass; the smaller the modulus, the lower the content of SiO ₂ and the higher the alkalinity of the potassium silicate glass. In the present invention, the potassium silicate with a modulus of 0.8-1.4 can provide suitable alkalinity and viscosity, and is beneficial to stimulate active substances in slag and silica fume.

Embodiment 4: This embodiment differs from Embodiments 1 to 3 in that the naphthalene-based water reducer is a β-naphthalene sulfonate formaldehyde condensate, which is a non-air-entraining water reducer. Other steps are the same as those in Embodiments 1 to 3.

Embodiment 5: The difference between this embodiment and Embodiment 1 to Embodiment 4 is that the silica fume is collected and dried from dust discharged from thermal power plants or cement plants. Other steps are the same as those in Embodiments 1 to 4.

Embodiment 6: The difference between this embodiment and Embodiments 1 to 5 is that the regenerated fine sand is any one or more of waste bricks and tiles, waste concrete, waste mortar and waste stones. Crushed mixture of fine particles. Other steps are the same as those in Embodiments 1 to 5.

Embodiment 7: The difference between this embodiment and Embodiments 1 to 6 is that the calcium sulfoaluminate expansion agent is obtained by mixing calcium sulfoaluminate and cement, wherein the calcium sulfoaluminate and cement The mass ratio is (1～2):(1～2). Other steps are the same as those in Embodiments 1 to 6.

Embodiment 8: This embodiment differs from Embodiments 1 to 7 in that: the particle size of the alkali slag is 30-100 μm; the particle size of the silica fume is 5-30 μm; the regeneration The particle size of the fine sand is 0.3 mm to 1 mm. Other steps are the same as those in Embodiments 1 to 7.

Embodiment 9: The difference between this embodiment and Embodiments 1 to 8 is that a preparation method for a material for repairing concrete pavement cracks is carried out in accordance with the following steps:

1. Dissolve NaOH and naphthalene-based water reducer in potassium silicate with a modulus of 0.8-1.4 to obtain an alkali activator;

The mass ratio of NaOH and potassium water glass described in step 1 is 0.2479:1, and the mass ratio of naphthalene-based water reducer and potassium water glass is (0.45～0.77):1;

2. Mix industrial waste slag or quasi-slag powder with alkali activator to obtain alkali slag;

The mass ratio of industrial waste slag or class slag powder and alkali activator described in step 2 is 5.37:1;

3. Weigh 30% to 50% of alkali slag, 10% to 15% of silica fume, 10% to 40% of recycled fine sand, 5% to 15% of calcium sulfoaluminate expansion agent and 10% ~25% water, mixed evenly, to obtain the material for repairing cracks in concrete pavement. Other steps are the same as those in Embodiments 1 to 8.

Embodiment 10: The difference between this embodiment and Embodiments 1 to 9 is that the method of using the material for repairing concrete pavement cracks described in step 3 is: pouring the material for repairing concrete pavement cracks into In the cracks of the concrete pavement, it shall be compacted and smoothed, and the repair of the cracks of the concrete pavement shall be completed after the material hardens. Other steps are the same as those in Embodiments 1 to 9.

Adopt the following examples to verify the beneficial effects of the present invention:

Embodiment 1: a kind of preparation method for the material of concrete pavement crack repair is to carry out according to the following steps:

1. Preparation of silica fume, recycled fine sand and calcium sulfoaluminate expansion agent;

①. Collect and dry the dust discharged from thermal power plants or cement plants to obtain silica fume;

②. Use a ball mill to pulverize the waste bricks to obtain regenerated fine sand after screening and washing;

③, calcium sulfoaluminate and cement are mixed evenly in a mass ratio of 1:2 to obtain calcium sulfoaluminate expansion agent;

2. NaOH and naphthalene-based water reducer are dissolved in potassium silicate with a modulus of 1.0 to obtain an alkali activator;

The mass ratio of NaOH described in step 1 and potassium water glass is 0.2479:1, and the mass ratio of naphthalene series water reducer and potassium water glass is 0.6:1;

3. Mix industrial waste slag or quasi-slag powder with alkali activator to obtain alkali slag;

The mass ratio of industrial waste slag or class slag powder and alkali activator described in step 2 is 5.37:1;

4. Weigh 40% alkali slag, 15% silica fume, 15% regenerated fine sand, 10% calcium sulfoaluminate expansion agent and 20% water according to the mass fraction, and mix evenly to obtain the concrete pavement crack repair materials;

The particle size of the alkali slag described in step 4 is 30-100 μm; the particle size of the silica fume is 5-30 μm; the particle size of the regenerated fine sand is 0.3 mm-1 mm;

The material that is used for the repair of concrete pavement crack that 75kg embodiment 1 prepares is poured in the concrete pavement crack (the length of crack is 10m, wide is 0.5m, is deep 3cm), compacting and smoothing, after material hardening promptly completes repairing For the repair of concrete pavement cracks, the strength of the repaired pavement has reached 90% of the original pavement, and the durability and impermeability have also been significantly improved.

Embodiment 2: a kind of preparation method for the material of concrete pavement crack repair is to carry out according to the following steps:

1. Preparation of silica fume, recycled fine sand and calcium sulfoaluminate expansion agent;

①. Collect and dry the dust discharged from thermal power plants or cement plants to obtain silica fume;

②. Use a ball mill to pulverize the waste concrete blocks, and then sieve and wash to obtain regenerated fine sand;

③, calcium sulfoaluminate and cement are mixed evenly in a mass ratio of 1:2 to obtain calcium sulfoaluminate expansion agent;

2. NaOH and naphthalene-based water reducer are dissolved in potassium silicate with a modulus of 1.0 to obtain an alkali activator;

The mass ratio of NaOH described in step 1 and potassium water glass is 0.2479:1, and the mass ratio of naphthalene series water reducer and potassium water glass is 0.65:1;

3. Mix industrial waste slag or quasi-slag powder with alkali activator to obtain alkali slag;

The mass ratio of industrial waste slag or class slag powder and alkali activator described in step 2 is 5.37:1;

4. Take 50% alkali slag, 10% silica fume, 20% regenerated fine sand, 5% calcium sulfoaluminate expansion agent and 15% water according to the mass fraction, and mix them evenly to obtain the concrete pavement cracking agent. repair materials;

The particle size of the alkali slag described in step 4 is 30-100 μm; the particle size of the silica fume is 5-30 μm; the particle size of the regenerated fine sand is 0.3 mm-1 mm;

32kg of the material prepared in Example 2 for repairing concrete pavement cracks is poured into the concrete pavement cracks (the length of the crack is 8m, the width is 0.4m, and the depth is 2cm), compacted and smoothed, and the repair is completed after the material is hardened. For the repair of concrete pavement cracks, the strength of the repaired pavement has reached 95% of the original pavement, and the durability and impermeability have also been significantly improved.

Embodiment 3: a kind of preparation method for the material of concrete pavement crack repair is to carry out according to the following steps:

1. Preparation of silica fume, recycled fine sand and calcium sulfoaluminate expansion agent;

①. Collect and dry the dust discharged from thermal power plants or cement plants to obtain silica fume;

②. Use a ball mill to crush the discarded stones, and then sieve and wash them to obtain regenerated fine sand;

③, calcium sulfoaluminate and cement are mixed evenly in a mass ratio of 1:2 to obtain calcium sulfoaluminate expansion agent;

2. NaOH and naphthalene-based water reducer are dissolved in potassium silicate with a modulus of 1.0 to obtain an alkali activator;

The mass ratio of NaOH described in step 1 and potassium water glass is 0.2479:1, and the mass ratio of naphthalene series water reducer and potassium water glass is 0.55:1;

3. Mix industrial waste slag or quasi-slag powder with alkali activator to obtain alkali slag;

The mass ratio of industrial waste slag or class slag powder and alkali activator described in step 2 is 5.37:1;

4. Take 30% alkali slag, 20% silica fume, 10% regenerated fine sand, 15% calcium sulfoaluminate expansion agent and 25% water according to the mass fraction, and mix them evenly to obtain the concrete pavement cracking agent. repair materials;

The particle size of the alkali slag described in step 4 is 30-100 μm; the particle size of the silica fume is 5-30 μm; the particle size of the regenerated fine sand is 0.3 mm-1 mm;

The material that 144kg embodiment 3 is used for concrete pavement crack repair is poured in the concrete pavement crack (the length of the crack is 12m, wide is 0.6m, and is 4cm deep), compacting and smoothing, after the material is hardened, promptly complete the repair. For the repair of concrete pavement cracks, the strength of the repaired pavement has reached 85% of the original pavement, and the durability and impermeability have also been significantly improved.

Embodiment 4: a kind of preparation method for the material of concrete pavement crack repair is to carry out according to the following steps:

1. Preparation of silica fume, recycled fine sand and calcium sulfoaluminate expansion agent;

①. Collect and dry the dust discharged from thermal power plants or cement plants to obtain silica fume;

②. Use a ball mill to pulverize the waste bricks to obtain regenerated fine sand after screening and washing;

③, calcium sulfoaluminate and cement are mixed evenly in a mass ratio of 1:2 to obtain calcium sulfoaluminate expansion agent;

2. NaOH and naphthalene-based water reducer are dissolved in potassium silicate with a modulus of 1.0 to obtain an alkali activator;

The mass ratio of NaOH described in step 1 and potassium water glass is 0.2479:1, and the mass ratio of naphthalene series water reducer and potassium water glass is 0.75:1;

3. Mix industrial waste slag or quasi-slag powder with alkali activator to obtain alkali slag;

The mass ratio of industrial waste slag or class slag powder and alkali activator described in step 2 is 5.37:1;

4. Take 45% alkali slag, 15% silica fume, 15% regenerated fine sand, 5% calcium sulfoaluminate expansion agent and 20% water according to the mass fraction, and mix them evenly to obtain the concrete pavement crack repair materials;

The particle size of the alkali slag described in step 4 is 30-100 μm; the particle size of the silica fume is 5-30 μm; the particle size of the regenerated fine sand is 0.3 mm-1 mm;

The material that is used for the repair of concrete pavement crack that 27kg embodiment 4 is prepared pours in the concrete pavement crack (the length of the crack is 6m, wide is 0.3m, and is deep 3cm), compacting and smoothing, after the material is hardened, promptly finish repairing For the repair of concrete pavement cracks, the strength of the repaired pavement has reached 90% of the original pavement, and the durability and impermeability have also been significantly improved.

Embodiment 5: a kind of preparation method for the material of concrete pavement crack repair is to carry out according to the following steps:

1. Preparation of silica fume, recycled fine sand and calcium sulfoaluminate expansion agent;

①. Collect and dry the dust discharged from thermal power plants or cement plants to obtain silica fume;

②. Use a ball mill to crush the discarded stones, and then sieve and wash them to obtain regenerated fine sand;

③, calcium sulfoaluminate and cement are mixed evenly in a mass ratio of 1:2 to obtain calcium sulfoaluminate expansion agent;

2. NaOH and naphthalene-based water reducer are dissolved in potassium silicate with a modulus of 1.0 to obtain an alkali activator;

The mass ratio of NaOH described in step 1 and potassium water glass is 0.2479:1, and the mass ratio of naphthalene series water reducer and potassium water glass is 0.7:1;

3. Mix industrial waste slag or quasi-slag powder with alkali activator to obtain alkali slag;

The mass ratio of industrial waste slag or class slag powder and alkali activator described in step 2 is 5.37:1;

4. Take 35% alkali slag, 10% silica fume, 20% regenerated fine sand, 10% calcium sulfoaluminate expansion agent and 25% water according to the mass fraction, and mix them evenly to obtain the concrete pavement crack repair materials;

The particle size of the alkali slag described in step 4 is 30-100 μm; the particle size of the silica fume is 5-30 μm; the particle size of the regenerated fine sand is 0.3 mm-1 mm;

The material that 50kg embodiment 5 is used for concrete pavement crack repairing is poured in the concrete pavement crack (the length of the crack is 10m, wide is 0.5m, and is 2cm deeply), compacting and smoothing, after the material is hardened, promptly finish repairing For the repair of concrete pavement cracks, the strength of the repaired pavement has reached 90% of the original pavement, and the durability and impermeability have also been significantly improved.

Fig. 1 is the mechanical performance test piece of embodiment 1, (a) figure is prismatic bending resistance, compressive test piece, (b) figure is dumbbell-shaped tensile test piece;

Fig. 2 is the damage figure of the mechanical performance test piece of embodiment 1, (a) figure is the fracture resistance figure, (b) figure is the compressive damage figure, (c) figure is the tensile damage figure;

Fig. 3 is the bonding performance test piece of embodiment 1, (a) figure is the prismatic bonded flexural test piece, (b) figure is the dumbbell-shaped bonded tensile test piece;

Fig. 4 is the damage diagram of the bond performance test piece of embodiment 1, (a) figure is the bonded anti-bending damage figure, (b) figure is the bonded tensile damage figure;

The mechanical properties of the material used for repairing concrete pavement cracks prepared in Examples 1 to 5 are tested, and the test results are shown in Table 1;

Table 1

The tensile strength in Table 1 is tested according to GB/T 17671-2021 "Cement Mortar Strength Test Method (ISO Method)";

The compressive strength in Table 1 is tested according to GB/T 17671-2021 "Cement Mortar Strength Test Method (ISO Method)";

The flexural strength in Table 1 is tested according to GB/T 17671-2021 "Cement Mortar Strength Test Method (ISO Method)";

The bonding tensile strength in Table 1 is tested according to GB/T 17671-2021 "Cement Mortar Strength Test Method (ISO Method)";

The bonding flexural strength in Table 1 is tested according to GB/T 17671-2021 "Cement Mortar Strength Test Method (ISO Method)";

The initial setting time in Table 1 is tested according to GB/T 17671-2021 "Cement mortar strength test method (ISO method)";

The final setting time in Table 1 is tested according to GB/T 17671-2021 "Cement Mortar Strength Test Method (ISO Method)".

Freeze-thaw cycle conditions: put the alkali slag cementitious material-cement mortar bond performance test piece that has been cured for 28 days at minus 25°C for 45 minutes, then thaw at 25°C for 45 minutes at room temperature, and test its properties after 100 freeze-thaw cycles. Bond strength.

Chloride ion corrosion conditions: Soak the alkali slag cementitious material-cement mortar bond performance test piece that has been cured for 28 days in 10% NaCl solution for 7 days, and then test its bond strength.

The data of the material used for concrete pavement crack repair before freezing, after freezing, before corrosion and after corrosion prepared by embodiments 1 to 5 are listed in Table 2;

Table 2

Comparative example 1: the slag among the embodiment 1 is replaced with other commonly used cementitious materials, such as cement, is to be finished according to the following steps:

1. Preparation of silica fume, recycled fine sand and calcium sulfoaluminate expansion agent;

①. Collect and dry the dust discharged from thermal power plants or cement plants to obtain silica fume;

②. Use a ball mill to pulverize the waste bricks to obtain regenerated fine sand after screening and washing;

③, calcium sulfoaluminate and cement are mixed evenly in a mass ratio of 1:2 to obtain calcium sulfoaluminate expansion agent;

2. Weigh 40% cement, 15% silica fume, 15% regenerated fine sand, 10% calcium sulfoaluminate expansion agent and 20% water according to the mass fraction, and mix them evenly to obtain the concrete pavement crack repair s material;

The particle size of the alkali slag in step 4 is 30-100 μm; the particle size of the silica fume is 5-30 μm; the particle size of the regenerated fine sand is 0.3 mm-1 mm.

The material compressive strength (28d): 35.36MPa, tensile strength (28d): 1.13MPa, flexural strength (28d): 7.27MPa, bonded flexural strength prepared by comparative example 1 for concrete pavement crack repair (28d): 3.26MPa, bond tensile strength (28d): 1.14MPa, bond strength after freeze-thaw cycles (100 times): flexural resistance: 1.77MPa, tensile strength 0.85MPa, chloride ion corrosion (10% concentration 7 Days) post bond strength: flexural: 1.95MPa, tensile 0.92MPa.

Comparative example 2: the slag among the embodiment 2 is replaced with other commonly used cementitious materials, such as cement, is finished in the following steps:

1. Preparation of silica fume, recycled fine sand and calcium sulfoaluminate expansion agent;

①. Collect and dry the dust discharged from thermal power plants or cement plants to obtain silica fume;

②. Use a ball mill to pulverize the waste bricks to obtain regenerated fine sand after screening and washing;

③, calcium sulfoaluminate and cement are mixed evenly in a mass ratio of 1:2 to obtain calcium sulfoaluminate expansion agent;

2. Weigh 50% cement, 10% silica fume, 20% regenerated fine sand, 5% calcium sulfoaluminate expansion agent and 15% water according to the mass fraction, and mix them evenly to obtain the concrete pavement crack repair s material;

The particle size of the alkali slag in step 4 is 30-100 μm; the particle size of the silica fume is 5-30 μm; the particle size of the regenerated fine sand is 0.3 mm-1 mm.

The material compressive strength (28d): 40.33MPa, tensile strength (28d): 2.05MPa, flexural strength (28d): 7.15MPa, bonded flexural strength prepared by comparative example 2 for concrete pavement crack repair (28d): 3.78MPa, bond tensile strength (28d) 1.26MPa, bond strength after freeze-thaw cycles (100 times): flexural resistance: 2.95MPa, tensile strength 0.97MPa, chloride ion corrosion (10% concentration for 7 days ) After bonding strength: flexural: 2.38MPa, tensile 1.05MPa.

Claims (10)

1. A material for repairing concrete pavement cracks is characterized in that it consists of 30% to 50% alkali slag, 10% to 15% silica fume, 10% to 40% regenerated fine sand, 5% %-15% of calcium sulfoaluminate expansion agent and 10%-25% of water. 2. A kind of material for concrete pavement crack repair according to claim 1, it is characterized in that described alkali slag is obtained after being excited by alkali slag powder by industrial waste slag or quasi-slag powder, wherein industrial waste slag or quasi-slag powder The mass ratio of slag powder to alkali activator is 5.37:1. 3. A kind of material for concrete pavement crack repair according to claim 2, it is characterized in that described alkali activator is that NaOH and naphthalene series water reducing agent are dissolved in the potassium silicate of modulus 0.8～1.4 prepared in , wherein the mass ratio of NaOH to potassium water glass is 0.2479:1, and the mass ratio of naphthalene-based water reducer to potassium water glass is (0.45-0.77):1. 4. A material for repairing concrete pavement cracks according to claim 3, characterized in that said naphthalene-based water reducer is β-naphthalenesulfonate formaldehyde condensate, which is a non-air-entraining water reducer Aqua. 5. A material for repairing cracks in concrete pavements according to claim 1, characterized in that said silica fume is collected and dried from dust discharged from thermal power plants or cement plants. 6. A material for repairing cracks in concrete pavement according to claim 1, characterized in that the regenerated fine sand is any one or both of discarded bricks and tiles, discarded concrete, discarded mortar and discarded stones A mixture of the above crushed fine particles. 7. A kind of material for concrete pavement crack repair according to claim 1, it is characterized in that described calcium sulfoaluminate expansion agent is obtained after mixing calcium sulfoaluminate and cement, wherein calcium sulfoaluminate The mass ratio with cement is (1～2):(1～2). 8. A material for repairing cracks in concrete pavement according to claim 1, characterized in that the particle size of the alkali slag is 30-100 μm; the particle size of the silica fume is 5-30 μm; The particle size of the regenerated fine sand is 0.3 mm to 1 mm. 9. a kind of preparation method for the material of concrete pavement crack repair according to claim 1 is characterized in that it is to carry out according to the following steps: 1. Dissolve NaOH and naphthalene-based water reducer in potassium silicate with a modulus of 0.8-1.4 to obtain an alkali activator; The mass ratio of NaOH and potassium water glass described in step 1 is 0.2479:1, and the mass ratio of naphthalene-based water reducer and potassium water glass is (0.45～0.77):1; 2. Mix industrial waste slag or quasi-slag powder with alkali activator to obtain alkali slag; The mass ratio of industrial waste slag or class slag powder and alkali activator described in step 2 is 5.37:1; 3. Weigh 30% to 50% of alkali slag, 10% to 15% of silica fume, 10% to 40% of recycled fine sand, 5% to 15% of calcium sulfoaluminate expansion agent and 10% ~25% water, mixed evenly, to obtain the material for repairing cracks in concrete pavement. 10. a kind of preparation method for the material that is used for concrete pavement crack repair according to claim 9, it is characterized in that the using method of the material that is used for concrete pavement crack repair described in step 3 is: will be used for concrete pavement The crack repairing material is poured into the cracks of the concrete pavement, compacted and smoothed, and the cracks of the concrete pavement are repaired after the material hardens.