CN109020421A - A kind of composite fibre fast repairing material and preparation method thereof - Google Patents

Abstract

The invention discloses a kind of composite fibre fast repairing material and preparation method thereof, organic short fiber: inorganic long fiber: low alkali sulphate aluminium cement: water-reducing agent: defoaming agent=0.9~1.1:2.0~2.5:100:0.5~1:0.03~0.05；Preparation method is as follows: 1) weighing each component and water according to mass ratio；2) water-reducing agent is soluble in water that aqueous solution, aqueous 1/3~1/2 are mixed with low alkali sulphate aluminium cement, it persistently stirs 30s~45s and obtains mortar；3) organic short fiber, inorganic long fiber, defoaming agent and remaining aqueous solution are added into mortar, stirs 30s~45s.Organic staple fibers peacekeeping inorganic long fiber passes through organic solvent and pure-acrylic emulsion surface modification treatment.The fast repairing material overcomes the features such as ordinary cement patching material strength development is slow, flexural strength is low, contraction is big, is highly suitable for the Rapid-Repair of road surface.

Description

A composite fiber rapid repair material and preparation method thereof

technical field

The patent of the invention relates to a composite fiber rapid repair material and a preparation method thereof, belonging to the field of civil engineering materials.

Background technique

In my country, cement concrete pavement is one of the main structural forms of high-grade pavement. Its main advantages are: strong bearing capacity, high temperature stability, long fatigue life, long service life, and wide source of materials. However, the cement concrete pavement itself is relatively brittle, and in engineering practice, due to some unqualified raw materials, inadequate design and maintenance, etc., the cement concrete pavement often suffers from different degrees of damage, which will greatly affect the comfort and safety of driving. Safety, if it is not repaired in time, it may also cause damage to the roadbed, or even block the entire road.

The problem with the cement concrete pavement repair materials currently used is that their hydration time is long, and it generally takes 5 to 7 days before they can be put into use, which is difficult to meet the needs of current highways, urban roads and other transportation hubs; in addition, repair materials are also required. High strength and good durability, that is, high flexural strength, bonding strength and toughness, low shrinkage, etc.

Sulphoaluminate cement has the characteristics of rapid strength development, micro-expansion after hydration reaction, and low alkalinity. It is very suitable as a rapid repair material, but it also has the disadvantages of low flexural strength and low toughness of cement concrete; After a certain amount of fiber, the flexural strength and toughness of cement concrete will be significantly improved. Although the most widely used steel fiber concrete can meet the requirements in terms of strength and toughness, if the steel fiber is not handled properly, it is easy to rust, and it also poses a safety hazard to vehicle tires in road surface repairs. However, inorganic long fibers with high strength and high elastic modulus, such as alkali-resistant glass fibers, do not have the problem of rust and will not affect driving safety, so they are very suitable as internal fibers for sulphoaluminate cement repairs.

The fast repair material needs to be put into use as soon as possible after repair, which means that it is difficult to achieve standard maintenance conditions. At this time, the surface of the repair material is prone to drying shrinkage due to water evaporation, or even cracking, which seriously affects the repair effect; while organic short fibers can Inhibit the appearance of drying shrinkage cracks in the early stage of hydration, such as polypropylene fiber, polyvinyl alcohol fiber, peroxyacetyl nitrate fiber, etc.; organic fibers are distributed in random directions in the rapid repair material, which can play a certain role in its early shrinkage The confinement effect reduces the early shrinkage of the repair material, thereby reducing the risk of early cracking.

Contents of the invention

Technical problem: The purpose of this invention is to provide a composite fiber rapid repair material and its preparation method. The composite fiber rapid repair material has the advantages of micro-expansion, fast strength development, high flexural strength, and is not easy to crack early, and its preparation method The process is simple and suitable for large-scale production applications.

Technical solution: The invention provides a composite fiber rapid repair material, which comprises the following components according to the mass ratio:

Organic short fibers: inorganic long fibers: low-alkali sulfoaluminate cement: water reducer: defoamer = 0.9～1.1:2.0～2.5:100:0.5～1:0.03～0.05.

in:

The short organic fibers are polypropylene fibers, polyvinyl alcohol fibers or peroxyacetyl nitrate fibers, the length of which is 2 mm to 6 mm, the diameter is 0.05 mm to 0.1 mm, and the modulus of elasticity is not higher than 5 GPa.

The long inorganic fibers are alkali-resistant glass fibers or carbon fibers, the length of which is 6mm-15mm, the diameter of single filament is 7μm-12μm, and the modulus of elasticity is higher than 70GPa.

The low-alkali sulphoaluminate cement is grade 42.5 low-alkali sulphoaluminate cement, and its 28-day volume expansion rate is greater than 1%.

The described water reducer is a polycarboxylate water reducer with a solid content of 40% to 50% and a water reducing rate of 35% to 36%; the described defoamer is a polyether type defoamer, modified from It is compounded with silicone polyether and modified siloxane, and its pH value is 6.5-8.5.

The organic short fibers and inorganic long fibers are modified organic short fibers and modified inorganic long fibers which are subjected to surface modification treatment by organic solvent and pure acrylic emulsion in sequence.

The organic solvent is ethanol or acetone; the pure acrylic emulsion is methacrylate, acrylate and acrylic acid ternary copolymer emulsion, and the pure acrylic emulsion also contains 0.2wt% to 0.3wt% of propylene Nitrile, 0.15wt%-0.2wt% allyl peptide amine, 0.1wt%-0.14wt% melamine.

The present invention also provides a kind of preparation method of composite fiber rapid repair material, and this preparation method comprises the following steps:

1) Weigh organic short fibers, inorganic long fibers, low-alkali sulphoaluminate cement, water reducer, and defoamer according to the mass ratio for later use, and use the mass ratio of low-alkali sulphoaluminate cement to water as 100:32 ~38 weigh water;

2) Dissolve the water reducer in the weighed water to obtain an aqueous solution, take 1/3 to 1/2 of the aqueous solution and mix it with low-alkali sulfoaluminate cement, and continue stirring for 30s to 45s to obtain mortar;

3) Add weighed short organic fibers, long inorganic fibers, defoamer and remaining aqueous solution into the mortar, and stir for 30s to 45s to obtain the composite fiber rapid repair material.

in:

The frequency of stirring described in step 2) and step 3) is 60r/min-80r/min.

Since the quick-hardening cement hydrates quickly, the sum of the time used in step 2) and step 3) is less than 90s.

The short organic fibers and long inorganic fibers are all modified organic short fibers and long inorganic fibers after surface modification treatment by organic solvent and pure acrylic emulsion in sequence, and the modification steps are as follows:

Step 1. First soak organic short fibers or long inorganic fibers in an organic solvent and vibrate for 3 to 5 minutes with an ultrasonic cleaner, then wash off the organic solvent on the surface of the fibers and dry them at 40°C to 60°C;

Step 2. Soak the dried organic short fibers or inorganic long fibers in pure acrylic emulsion for 3-5 minutes again, then take them out and dry them at room temperature to obtain modified organic short fibers or modified inorganic long fibers.

Beneficial effect: compared with the prior art, the present invention has the following advantages:

1. The composite fiber rapid repair material provided by the present invention has good construction performance, light weight, rapid strength development, reliable finished product strength, and has the potential to quickly repair infrastructure such as roads, bridges, and tunnels;

2. The present invention uses micro-expansion low-alkali sulfoaluminate cement, which effectively compensates for shrinkage and cracking caused by hydration and excessive water volatilization, and greatly reduces the risk of volume stability of repair materials; organic short fibers and inorganic long fibers are used Composite matching can improve the workability of freshly mixed slurry, improve construction efficiency, and at the same time enhance the anti-cracking risk ability of repair materials and systems, which is very suitable for rapid repair of roads, bridges and tunnels and other application scenarios;

3. The preparation method of the composite fiber rapid repair material provided by the present invention has a simple process and is suitable for large-scale production and application.

Detailed ways

The present invention will be further elaborated below in conjunction with embodiment.

Example 1:

A composite fiber rapid repair material, comprising the following components according to the mass ratio:

Organic short fibers: inorganic long fibers: low-alkali sulphoaluminate cement: water reducer: defoamer = 0.9: 2.5: 100: 0.7: 0.05.

Select polyvinyl alcohol fiber as organic short fiber, its density is 1.3g/cm ³ , length is 3mm, diameter is 0.05mm, elastic modulus is 4.7GPa, and its surface is modified by acetone and pure acrylic emulsion in turn;

Alkali-resistant glass fiber is selected as the inorganic long fiber, the length of which is 6mm, the diameter of the single filament is 7μm, and the elastic modulus is 80GPa, which is subjected to surface modification treatment by acetone and pure acrylic emulsion in turn;

For low-alkali sulfoaluminate cement, choose rapid hardening type 42.5 grade low-alkali sulfoaluminate cement, and the volume expansion rate in 28 days is greater than 1%;

The superplasticizer is high-efficiency polycarboxylate superplasticizer with a solid content of 40% and a water reducing rate of 35%;

The defoamer is polyether type defoamer, which is compounded by modified silicon polyether and modified siloxane, with a pH value of 8.

A preparation method of composite fiber fast repair material, the preparation method comprises the following steps:

1) Weigh organic short fibers, inorganic long fibers, low-alkali sulphoaluminate cement, water reducer, and defoamer according to the mass ratio for later use, and use the mass ratio of low-alkali sulphoaluminate cement to water as 100:38 Weigh water;

2) Dissolve the water reducer in the weighed water to obtain an aqueous solution, take 1/3 of the aqueous solution and mix it with low-alkali sulphoaluminate cement and add it to the mixer, and keep stirring for 30 seconds at a stirring frequency of 60r/min to obtain a mortar;

3) Add weighed short organic fibers, long inorganic fibers, defoamer and remaining aqueous solution to the mortar, and stir for 30 seconds at a stirring frequency of 60 r/min to obtain the composite fiber rapid repair material.

in:

The short organic fibers and long inorganic fibers are all modified organic short fibers and long inorganic fibers after surface modification treatment by acetone and pure acrylic emulsion in turn, and the modification steps are as follows:

Step 1. First, soak organic short fibers or inorganic long fibers in acetone and vibrate for 3 minutes with an ultrasonic cleaner, then wash off the organic solvent on the surface of the fibers and dry them at 40°C;

Step 2. Soak the dried organic short fibers or inorganic long fibers in pure acrylic emulsion for 3 minutes again, then take them out and dry them at room temperature to obtain modified organic short fibers or modified inorganic long fibers.

The pure acrylic emulsion is a ternary copolymerization emulsion of methacrylates, acrylates and acrylic acid, and the pure acrylic emulsion also contains 0.2wt% acrylonitrile, 0.15wt% allyl peptide amine, 0.1wt% melamine .

The composite fiber fast repair material finally obtained after testing has a 28d expansion rate of about 1%, a compressive strength of about 40MPa, and a flexural strength of not less than 10MPa, and is not prone to early cracking.

Example 2:

A composite fiber rapid repair material, comprising the following components according to the mass ratio:

Organic short fibers: inorganic long fibers: low-alkali sulfoaluminate cement: water reducer: defoamer = 0.9: 2.5: 100: 1.0: 0.05.

The organic short fiber is polypropylene fiber, which has a density of 0.91g/cm3, a length of 4mm, a diameter of 0.06mm, and an elastic modulus of 4.6GPa, and its surface is modified by acetone and pure acrylic emulsion in turn;

Carbon fiber is selected as the inorganic long fiber, with a length of 9mm, a single filament diameter of 8μm, and an elastic modulus of 230GPa, which are surface-modified by acetone and pure acrylic emulsion in turn;

For low-alkali sulfoaluminate cement, choose rapid hardening type 42.5 grade low-alkali sulfoaluminate cement, and the volume expansion rate in 28 days is greater than 1%;

The superplasticizer is high-efficiency polycarboxylate superplasticizer with a solid content of 47% and a water reducing rate of 35.3%;

The defoamer is a polyether type defoamer, which is composed of modified silicon polyether and modified siloxane, with a pH value of 7.

A preparation method of composite fiber fast repair material, the preparation method comprises the following steps:

1) Weigh organic short fibers, inorganic long fibers, low-alkali sulphoaluminate cement, water reducer, and defoamer according to the mass ratio for later use, and use the mass ratio of low-alkali sulphoaluminate cement to water as 100:35 Weigh water;

2) Dissolve the water reducer in the weighed water to obtain an aqueous solution, take 1/2 of the aqueous solution and mix it with low-alkali sulphoaluminate cement and add it to the mixer, and keep stirring for 45 seconds at a stirring frequency of 70r/min to obtain a mortar;

3) Add weighed short organic fibers, long inorganic fibers, defoamer and remaining aqueous solution to the mortar, and stir for 45 seconds at a stirring frequency of 70 r/min to obtain the composite fiber rapid repair material.

in:

The short organic fibers and long inorganic fibers are all modified organic short fibers and long inorganic fibers after surface modification treatment by acetone and pure acrylic emulsion in turn, and the modification steps are as follows:

Step 1. First, soak organic short fibers or inorganic long fibers in acetone and vibrate for 5 minutes with an ultrasonic cleaner, then wash off the organic solvent on the surface of the fibers and dry them at 40°C;

Step 2. Soak the dried organic short fibers or inorganic long fibers in pure acrylic emulsion for 5 minutes again, then take them out and dry them at room temperature to obtain modified organic short fibers or modified inorganic long fibers.

The pure acrylic emulsion is methacrylate, acrylate and acrylic acid ternary copolymer emulsion, and the pure acrylic emulsion also contains 0.23wt% acrylonitrile, 0.16wt% allyl peptide amine, and 0.11wt% melamine.

After testing, the composite fiber rapid repair material finally obtained has a 28d expansion rate of about 1%, a compressive strength of about 40MPa, and a flexural strength of not less than 13MPa, and is not prone to early cracking.

Example 3:

A composite fiber rapid repair material, comprising the following components according to the mass ratio:

Organic short fibers: inorganic long fibers: low-alkali sulfoaluminate cement: water reducer: defoamer = 1.0: 2.3: 100: 0.7: 0.04.

Select polyvinyl alcohol fiber as organic short fiber, its density is 1.3g/cm ³ , length is 5mm, diameter is 0.08mm, elastic modulus is 4.4GPa, and its surface is modified by acetone and pure acrylic emulsion in turn;

Alkali-resistant glass fiber is selected as the inorganic long fiber, with a length of 12 mm, a single filament diameter of 10 μm, and an elastic modulus of 80 GPa, which are surface-modified by acetone and pure acrylic emulsion in turn;

For low-alkali sulfoaluminate cement, choose rapid hardening type 42.5 grade low-alkali sulfoaluminate cement, and the volume expansion rate in 28 days is greater than 1%;

The superplasticizer is high-efficiency polycarboxylate superplasticizer with a solid content of 49% and a water reducing rate of 35.7%;

The defoamer is polyether type defoamer, which is compounded by modified silicon polyether and modified siloxane, with a pH value of 8.5.

A preparation method of composite fiber fast repair material, the preparation method comprises the following steps:

1) Weigh organic short fibers, inorganic long fibers, low-alkali sulphoaluminate cement, water reducer, and defoamer according to the mass ratio for later use, and use the mass ratio of low-alkali sulphoaluminate cement to water as 100:32 Weigh water;

2) Dissolve the water reducer in the weighed water to obtain an aqueous solution, take 1/2.3 of the aqueous solution and mix it with low-alkali sulfoaluminate cement and add it to the mixer, and keep stirring for 35 seconds at a stirring frequency of 75r/min to obtain mortar;

3) Add weighed short organic fibers, long inorganic fibers, defoamer and remaining aqueous solution to the mortar, and stir for 35 seconds at a stirring frequency of 75 r/min to obtain the composite fiber rapid repair material.

in:

The short organic fibers and long inorganic fibers are all modified organic short fibers and long inorganic fibers after surface modification treatment by acetone and pure acrylic emulsion in turn, and the modification steps are as follows:

Step 1. First, soak organic short fibers or long inorganic fibers in acetone and vibrate for 4 minutes with an ultrasonic cleaner, then wash off the organic solvent on the surface of the fibers and dry them at 60°C;

Step 2. Soak the dried organic short fibers or inorganic long fibers in pure acrylic emulsion for 4 minutes again, then take them out and dry them at room temperature to obtain modified organic short fibers or modified inorganic long fibers.

The pure acrylic emulsion is methacrylates, acrylates, a small amount of acrylic acid ternary copolymer emulsion, also contains 0.27wt% acrylonitrile, 0.18wt% allyl peptide amine, 0.13wt% acrylic acid Melamine.

After testing, the composite fiber rapid repair material finally obtained has a 28d expansion rate of about 1%, a compressive strength of about 45MPa, and a flexural strength of not less than 16MPa, and is not prone to early cracking.

Example 4:

A composite fiber rapid repair material, comprising the following components according to the mass ratio:

Organic short fibers: inorganic long fibers: low-alkali sulfoaluminate cement: water reducer: defoamer = 1.1: 2.0: 100: 0.5: 0.03.

Select polyvinyl alcohol fiber as organic short fiber, its density is 1.3g/cm ³ , length is 6mm, diameter is 0.10, elastic modulus is 4.2GPa, and its surface is modified by acetone and pure acrylic emulsion in turn;

Alkali-resistant glass fibers are selected as inorganic long fibers, with a length of 15 mm, a single filament diameter of 12 μm, and an elastic modulus of 80 GPa, which are surface-modified by acetone and pure acrylic emulsion in turn;

For low-alkali sulfoaluminate cement, choose rapid hardening type 42.5 grade low-alkali sulfoaluminate cement, and the volume expansion rate in 28 days is greater than 1%;

The superplasticizer is high-efficiency polycarboxylate superplasticizer with a solid content of 50% and a water reducing rate of 36%;

The defoamer is polyether type defoamer, which is compounded by modified silicon polyether and modified siloxane, with a pH value of 6.5.

A preparation method of composite fiber fast repair material, the preparation method comprises the following steps:

1) Weigh organic short fibers, inorganic long fibers, low-alkali sulphoaluminate cement, water reducing agent, and defoamer according to the mass ratio for later use, and use the mass ratio of low-alkali sulphoaluminate cement to water as 100:34 Weigh water;

2) Dissolve the water reducer in the weighed water to obtain an aqueous solution, take 1/2.7 of the aqueous solution and mix it with low-alkali sulfoaluminate cement and add it to the mixer, and keep stirring for 40 seconds at a stirring frequency of 80r/min to obtain mortar;

3) Add weighed short organic fibers, long inorganic fibers, defoamer and remaining aqueous solution to the mortar, and stir for 40 seconds at a stirring frequency of 80 r/min to obtain the composite fiber rapid repair material.

in:

The short organic fibers and long inorganic fibers are all modified organic short fibers and long inorganic fibers after surface modification treatment by acetone and pure acrylic emulsion in turn, and the modification steps are as follows:

Step 1. First, soak organic short fibers or long inorganic fibers in acetone and vibrate for 5 minutes with an ultrasonic cleaner, then wash off the organic solvent on the surface of the fibers and dry them at 50°C;

Step 2. Soak the dried organic short fibers or inorganic long fibers in pure acrylic emulsion for 5 minutes again, then take them out and dry them at room temperature to obtain modified organic short fibers or modified inorganic long fibers.

The pure acrylic emulsion is methacrylates, acrylic esters, a small amount of acrylic acid ternary copolymer emulsion, and the pure acrylic emulsion also contains 0.3wt% acrylonitrile, 0.2wt% allyl peptide amine, 0.14wt% melamine .

The composite fiber rapid repair material finally obtained after testing has a 28d expansion rate of about 1%, a compressive strength of about 40MPa, and a flexural strength of not less than 12MPa, and is not prone to early cracking.

Claims (10)

1. a kind of composite fibre fast repairing material, it is characterised in that: the patching material includes following components according to mass ratio:

Organic short fiber: inorganic long fiber: low alkali sulphate aluminium cement: water-reducing agent: defoaming agent=0.9~1.1:2.0~2.5: 100:0.5~1:0.03~0.05.

2. a kind of composite fibre fast repairing material as described in claim 1, it is characterised in that: the organic short fiber is Polypropylene fibre, vinal or Peroxyacetyl nitrate fiber, the length is 2mm~6mm, diameter be 0.05mm~ 0.1mm, elasticity modulus are not higher than 5GPa.

3. a kind of composite fibre fast repairing material as described in claim 1, it is characterised in that: the inorganic long fiber is Alkali-resistant glass fibre or carbon fiber, the length is 6mm~15mm, filament diameter be 7 μm~12 μm, elasticity modulus is higher than 70GPa。

4. a kind of composite fibre fast repairing material as described in claim 1, it is characterised in that: the low alkali aluminium sulfate Cement is 42.5 grades of low alkali sulphate aluminium cements, and cubical expansivity is greater than 1% within 28 days.

5. a kind of composite fibre fast repairing material as described in claim 1, it is characterised in that: the water-reducing agent is poly- carboxylic Sour water-reducing agent, solid content are 40%~50%, and water-reducing rate is 35%~36%；The defoaming agent is polyether-type defoaming agent, It is combined by modified silicon polyethers with modified siloxane, pH value is 6.5~8.5.

6. a kind of composite fibre fast repairing material as described in claim 1, it is characterised in that: the organic short fiber with Inorganic long fiber be successively the modification organic short fiber after organic solvent and pure-acrylic emulsion carry out surface modification treatment with change Property inorganic long fiber.

7. a kind of composite fibre fast repairing material as claimed in claim 6, it is characterised in that: the organic solvent is second Alcohol or acetone；The pure-acrylic emulsion is the ternary copolymer emulsion of methyl acrylic ester, esters of acrylic acid and acrylic acid, and In the pure-acrylic emulsion also the acrylonitrile containing 0.2wt%~0.3wt%, 0.15wt%~0.2wt% propylene peptamine, The melamine of 0.1wt%~0.14wt%.

8. a kind of preparation method of composite fibre fast repairing material as described in claim 1, it is characterised in that: the preparation side Method the following steps are included:

1) organic short fiber, inorganic long fiber, low alkali sulphate aluminium cement, water-reducing agent, defoaming agent are weighed according to mass ratio standby With, and water is weighed according to mass ratio 100:32~38 of low alkali sulphate aluminium cement and water；

2) water-reducing agent is dissolved in weighed water and obtains aqueous solution, aqueous 1/3~1/2 and low alkali sulphate aluminium cement are mixed It closes, persistently stirs 30s~45s and obtain mortar；

3) it is added load weighted organic short fiber, inorganic long fiber, defoaming agent and remaining aqueous solution into mortar, stirring 30s~ The composite fibre fast repairing material can be obtained in 45s.

9. a kind of preparation method of composite fibre fast repairing material as claimed in claim 8, it is characterised in that: step 2) with The frequency of stirring described in step 3) is 60r/min~80r/min.

10. a kind of preparation method of composite fibre fast repairing material as claimed in claim 8, it is characterised in that: described Organic short fiber, inorganic long fiber are that the modification successively after organic solvent and pure-acrylic emulsion carry out surface modification treatment is organic Staple fiber, modified inorganic long fibre, modification procedure are as follows:

Organic short fiber or inorganic long fiber are impregnated in organic solvent first and use supersonic cleaning machine vibration 3 by step 1 Fiber surface organic solvent is washed away again later and is dried at 40 DEG C~60 DEG C by~5min；

The organic short fiber of drying or inorganic long fiber are immersed in 3~5min in pure-acrylic emulsion, Zhi Houqu by step 2 again It dries out and at room temperature and obtains modified organic short fiber or modified inorganic long fibre.