WO2021128629A1

WO2021128629A1 - Sleeve grouting material for prefabricated components and preparation method therefor

Info

Publication number: WO2021128629A1
Application number: PCT/CN2020/082362
Authority: WO
Inventors: 李格丽; 方云辉; 朱少宏; 郭元强; 林添兴
Original assignee: 科之杰新材料集团有限公司
Priority date: 2019-12-24
Filing date: 2020-03-31
Publication date: 2021-07-01
Also published as: CN114685083B; CN112707683B; MY194806A; CN114685083A; CN112707683A

Abstract

The present invention relates to the field of prefabricated component building materials, and particularly relates to a sleeve grouting material for prefabricated components and a preparation method therefor. The grouting material is made by adding water and polycarboxylic acid water reducing agent to prefabricated component sleeve grouting material dry powder and mixing same; the sleeve grouting material dry powder is made of the following components: 70-100 parts by weight of cement, 75-100 parts by weight of mixed sand, 20-30 parts by weight of glass powder, 1-3 parts by weight of expanding agent, 1-3 parts by weight of thickening agent, and 1-3 parts by weight of toughening agent; the mass ratio of prefabricated component sleeve grouting material dry powder to water is 1:0.1-0.15; the polycarboxylic acid water reducing agent is comprehensive shrinkage type polycarboxylic acid water reducing agent, and the dosage is 2%-3%, having both a defoaming and a low hydration heat effect. The comprehensive shrinkage type polycarboxylic acid water reducing agent introduced in the present invention can effectively reduce the effect of air bubbles during use of the polycarboxylic acid water reducing agent, decrease the cement hydration heat, and reduce the shrinkage of the sleeve grouting material during use of the prefabricated components, being conducive to the large-scale popularisation and usage of prefabricated components.

Description

Sleeve grouting material for prefabricated component and preparation method thereof

Technical field

The invention relates to the field of prefabricated component building materials, in particular to a sleeve grouting material for prefabricated components and a preparation method thereof.

Background technique

As the concept of green environmental protection becomes more and more popular, for the construction industry, the application of green building materials and green buildings has become more and more extensive. Rebar sleeve grouting connection technology, as the main means of building green development, is involved in various fields such as industrial and civil construction, roads and bridges, underground engineering, ocean engineering, and nuclear power engineering. The grouting connection technology adopts the method of factory prefabricated components and on-site connection, which not only reduces the tedious process of construction, but also saves energy and reduces emissions and protects the environment. Factory prefabrication can guarantee the quality of prefabricated components. The safety and stability requirements of the entire structure largely depend on the connection between the steel bar and the sleeve. The modern construction requirements are getting higher and higher, and the performance of the sleeve grouting is also required. The better.

In recent years, there has been more and more research on the reinforced sleeve grouting material for prefabricated components. According to the Chinese standard "Grouting for Reinforced Sleeve Connection", the reinforced sleeve grouting material is a cement-based material with appropriate fine aggregates, and Additives, after adding water and stirring, a material with excellent fluidity, early strength, high strength, micro expansion and other properties. Cement-based grouting material is currently the most widely used grout material in grouting engineering. At present, the domestic grouting material is generally composed of cementing components, superplasticized components, and preferred high-strength micro-aggregates, but its performance and cost have become the bottleneck affecting its development.

The grouting materials currently used on the market need to add more admixture components, such as CN106830817A, a prefabricated concrete structure grouting material for prefabricated floor slabs. The publication date is June 13, 2017. The grouting material exists There are 22 different components, and many of them are uncommon chemical components. The raw materials for the preparation of grouting materials are not easy to obtain, and the practicability is not strong; in order to reduce the influence of air bubbles generated during the use of grouting materials and the impact of cement The hydration process is difficult to control and other problems. Most of the grouting materials used on the market are solved by adding defoamers, anti-foaming agents, retarders, etc. The addition of such additives may cause flow in engineering applications. Low performance brings inconvenience in construction.

The preparation of grouting material for reinforcing steel sleeve is prepared by weighing dry powder, adding water, and mixing, such as CN108530006A, a steel sleeve grouting material for fabricated structure connection and its preparation method, published on September 14, 2018; CN108147776A A high-performance grouting material for connecting low-temperature steel bars and a preparation method thereof, published on June 12, 2018, are all prepared by weighing all the components and then mixing them with a mixer. If all materials are directly weighed for mixing, there may be disadvantages such as uneven mixing of materials and unstable performance.

Summary of the invention

In order to solve the problem of poor fluidity during use of grouting materials mentioned in the above background art, the present invention provides a sleeve grouting material for prefabricated components, which is composed of dry powder of sleeve grouting material for prefabricated components and water and polycarboxylic acid reduction. The dry powder of the sleeve grouting material for prefabricated components is composed of the following components: 70-100 parts by weight of cement, 75-100 parts by weight of mixed sand, 20-30 parts by weight of glass powder, and 1~ 3 parts by weight, 1 to 3 parts by weight of thickener, and 1 to 3 parts by weight of toughening agent; wherein the mass ratio of dry powder of sleeve grouting material for prefabricated member to water is 1:0.1-0.15; The acid water-reducing agent is a comprehensive shrinkage-reducing polycarboxylic acid water-reducing agent with a mixing amount of 2% to 3%, which has the effects of defoaming and low heat of hydration.

On the basis of the above scheme, further, the polycarboxylic acid water reducer is a comprehensive shrinkage type polycarboxylic acid water reducer, with a molecular weight of 30,000 to 50,000, and a water reduction rate of ≥30%, and its structural formula is as follows:

Wherein, R ₁ is -CH ₃ or -CH ₂ CH ₃ , R ₂ is -CH ₃ , R ₃ is -CF ₃ , R ₄ is -H or -CH ₃ , R ₅ is an alkyl group of 1 to 5, and M It is an alkyl group of _1-5 , M 1 is -H or alkyl H, M ₂ is Na or K, a and b are both positive integers, and a=1-20, b=1-50.

On the basis of the above solution, further, the mixed sand is a mixed sand of machine-made sand and molybdenum tailing sand, and the weight ratio of machine-made sand and molybdenum tailing sand is 1:0.1-0.2.

On the basis of the above solution, further, the mixed sand is a mixed sand of machine-made sand and molybdenum tailing sand, and the weight ratio of machine-made sand and molybdenum tailing sand is 1:0.15.

On the basis of the above solution, further, the glass powder is waste glass powder of 100 mesh to 200 mesh.

On the basis of the above solution, further, the waste glass powder is crushed and finely ground waste beer bottles, waste glass plates, and waste beverage bottles, and its silica content is greater than or equal to 80%.

On the basis of the above solution, further, the expansion agent is a water-soluble polyurethane, which is one of polyether type, polyester type, and ether ester mixed polyurethane.

On the basis of the above solution, further, the thickener is cellulose ether.

On the basis of the above solution, further, the thickener is one of hydroxyethyl methyl cellulose ether, hydroxypropyl methyl cellulose ether, and hydroxypropyl methyl cellulose ether.

On the basis of the above scheme, further, the toughening agent is one of methyl methacrylate-butadiene-styrene polymer, acrylonitrile-butadiene-styrene polymer, and chlorinated polyethylene Kind.

The present invention also provides a method for preparing sleeve grouting material for a prefabricated component according to any of the foregoing, which includes the following steps:

Step 1. Weigh each component in parts by weight;

Step 2. Mix the machine-made sand and molybdenum tailing sand in a mortar mixer at a medium speed for 3 to 5 minutes to obtain mixed sand;

Step 3. Add the thickener, toughening agent and expansion agent into the reaction kettle, add water, adjust the temperature to 20℃～40℃, stir for 10min～20min to make it dissolve;

Step 4. Under stirring, add the mixed sand and glass powder obtained in step 2 in step 3, and continue to stir for 20-30 minutes;

Step 5. Add polycarboxylic acid water-reducing agent and cement to the materials of step 4, stir uniformly for 10-20 minutes, and finally add the remaining amount of water to obtain sleeve grouting for prefabricated components.

Compared with the prior art, the reinforced sleeve dry powder grouting material for prefabricated components provided by the present invention involves the following technical principles and beneficial effects:

The polycarboxylate water reducer introduced in the present invention is a comprehensive shrinkage reduction type polycarboxylate water reducer, which can release the fluorocarbon structure and phosphoric acid in its molecular structure during the mixing process with water Ester structure, which has the functions of defoaming and reducing the heat of hydration, and the water reducing agent can reduce the surface tension of the liquid phase of the material under alkaline conditions, achieve the effect of reducing shrinkage, and greatly improve the flow performance. The grouting material prepared by the invention adds a toughening agent to reduce the weakness of the brittleness of the cement-based grouting material, and can be used to treat existing expansion joints and live joints.

In a preferred scheme, the present invention uses molybdenum tailings sand with a small fineness modulus and a machine-made sand with a large fineness modulus to make the mixed sand meet the requirements of gradation, and maintain good water consumption while maintaining good water consumption. The strength of the mixed sand, the filling effect of the mixed sand and the pozzolanic effect of the glass powder make the dry powder grouting system for the prepared steel sleeves compact, the reinforcement effect is obvious, and the mechanical properties are improved.

In a preferred scheme, the present invention uses water-soluble polyurethane as the expansion agent, which swells in contact with water, has the dual properties of elastic water-stopping and water-stopping, and its volume expansion rate is relatively large. The expansion rate can be changed by adjusting the water consumption to meet Different requirements for early expansion and later expansion.

In a preferred solution, the present invention uses molybdenum tailings sand and waste glass powder as raw materials for preparing the reinforced sleeve grouting material for prefabricated components, which belongs to waste utilization. The performance of the prepared reinforced sleeve grouting material can meet the requirements and is beneficial to the rationalization of resources. Utilization meets the requirements of sustainable development.

In the preparation method provided by the present invention, the specific preparation steps and process sequence are matched to make the prepared grouting material more uniform and more stable in performance.

Detailed ways

In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not All examples. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

The present invention also provides the following embodiments:

Example 1

In terms of parts by weight, weigh 63 parts of machine-made sand and 7 parts of molybdenum tailing sand, and mix them in a mortar mixer at medium speed for 5 minutes to obtain mixed sand. Add 1 part of water-soluble polyether polyurethane, 1 part of hydroxyethyl methyl cellulose ether, and 1 part of methyl methacrylate-butadiene-styrene polymer into the reactor, add water, and adjust the temperature to 20°C , Stir for 20 minutes to dissolve, then under stirring, add 20 parts of mixed sand and 100 mesh beer bottle ground powder, continue to stir for 20 minutes, then add 1 part of polycarboxylic acid water reducing agent and 70 parts of cement, and stir evenly for 20 minutes. The remaining amount of water is added to obtain the sleeve grouting material for the prefabricated component.

Example 2

In terms of parts by weight, weigh 68 parts of machine-made sand and 12 parts of molybdenum tailing sand, and mix them in a mortar mixer at medium speed for 4 minutes to obtain mixed sand. Add 2 parts of water-soluble polyester polyurethane, 2 parts of hydroxypropyl methyl cellulose ether, and 2 parts of acrylonitrile-butadiene-styrene polymer into the reactor, add water, adjust the temperature to 30℃, and stir for 15min , To dissolve, then under stirring, add 25 parts of mixed sand and 150 mesh waste glass ground powder, continue to stir for 25 minutes, then add 3 parts of polycarboxylic acid water reducing agent and 80 parts of cement, stir evenly for 15 minutes, add the balance Water to obtain the sleeve grouting material for the prefabricated component.

Example 3

In terms of parts by weight, weigh 68 parts of machine-made sand and 12 parts of molybdenum tailing sand, and mix them in a mortar mixer at medium speed for 3 minutes to obtain mixed sand. Add 2 parts of water-soluble polyester polyurethane, 2 parts of hydroxypropyl methyl cellulose ether, and 2 parts of acrylonitrile-butadiene-styrene polymer into the reactor, add water, adjust the temperature to 40℃, and stir for 10 minutes , To dissolve it, then under stirring, add 25 parts of mixed sand and 150 mesh waste glass ground powder, continue to stir for 30 minutes, then add 3 parts of polycarboxylic acid water reducing agent and 80 parts of cement, stir evenly for 20 minutes, add the balance Water to obtain the sleeve grouting material for the prefabricated component.

Example 4

In terms of parts by weight, weigh 80 parts of machine-made sand and 20 parts of molybdenum tailing sand, and mix them in a mortar mixer at medium speed for 5 minutes to obtain mixed sand. Add 3 parts of water-soluble polyester, polyether mixed polyurethane, 3 parts of hydroxypropyl methyl cellulose ether, and 3 parts of chlorinated polyethylene into the reactor, add water, adjust the temperature to 30°C, and stir for 15 minutes to make it Dissolve, then under stirring, add 30 parts of mixed sand and 200 mesh waste beverage bottle ground powder, continue to stir for 25 minutes, then add 5 parts of polycarboxylic acid water reducing agent and 100 parts of cement, stir evenly for 20 minutes, and add the balance of water , That is, the sleeve grouting material for the prefabricated component is obtained.

Comparison

In parts by weight, weigh 80 parts of ordinary Portland cement, 85 parts of quartz sand, 2 parts of expansion agent, 4 parts of standard high-performance water reducing agent, 0.5 part of defoamer, 0.5 part of retarder, and 20 parts of water , Placed in a mortar mixer and stirred for 20 minutes to obtain a reinforced sleeve grouting material for prefabricated components.

The test method in the grouting material JG/T408-2013 "Sleeve Grouting for Reinforcing Steel Bar Connection" prepared by the above comparative examples and examples was tested for performance, and the specific test data is shown in the following table:

Table 1

It can be seen from the above comparison that the present invention achieves good fluidity, high compressive strength, and good shrinkage effect by adding comprehensive shrinkage-reducing polycarboxylic acid water-reducing agent, water-soluble polyurethane expansion agent and composite sand. effect.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions recorded in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the technical solutions of the embodiments of the present invention. range.

Claims

A sleeve grouting material for prefabricated components is characterized in that: the dry powder of sleeve grouting material for prefabricated components is mixed with water and a polycarboxylic acid water reducing agent; the dry powder of sleeve grouting material for prefabricated components is composed of the following components Composition: 70-100 parts by weight of cement, 75-100 parts by weight of mixed sand, 20-30 parts by weight of glass powder, 1-3 parts by weight of expanding agent, 1-3 parts by weight of thickening agent, 1-3 parts by weight of toughening agent ；

Wherein, the mass ratio of the dry powder of the sleeve grouting material for the prefabricated member to the water is 1:0.1-0.15;

The polycarboxylic acid water-reducing agent is a comprehensive shrinkage-reducing polycarboxylic acid water-reducing agent with a blending amount of 2% to 3%, which has the effects of defoaming and low heat of hydration.
The sleeve grouting material for prefabricated components according to claim 1, characterized in that: the polycarboxylic acid water reducer is a comprehensive shrinkage type polycarboxylic acid water reducer with a molecular weight of 30,000 to 50,000 and a water reduction rate of ≥30 %, its structural formula is as follows:

Wherein, R 1 is -CH 3 or -CH 2 CH 3 , R 2 is -CH 3 , R 3 is -CF 3 , R 4 is -H or -CH 3 , R 5 is an alkyl group of 1 to 5, and M It is an alkyl group of 1-5 , M 1 is -H or alkyl H, M 2 is Na or K, a and b are both positive integers, and a=1-20, b=1-50.
The sleeve grouting material for prefabricated components according to claim 1, wherein the mixed sand is a mixed sand of machine-made sand and molybdenum tailing sand, and the weight ratio of machine-made sand and molybdenum tailing sand is 1:0.1-0.2.
The sleeve grouting material for prefabricated components according to claim 1, wherein the mixed sand is a mixed sand of machine-made sand and molybdenum tailing sand, and the weight ratio of machine-made sand and molybdenum tailing sand is 1:0.15.
The sleeve grouting material for prefabricated components according to claim 1, wherein the glass powder is waste glass powder of 100 mesh to 200 mesh.
The sleeve grouting material for prefabricated components according to claim 5, characterized in that: the waste glass powder is crushed and finely ground waste beer bottles, waste glass plates, and waste beverage bottles, and its silicon dioxide content is ≥80% .
The sleeve grouting material for prefabricated components according to claim 1, wherein the expansion agent is a water-soluble polyurethane, which is one of polyether type, polyester type, and ether ester mixed polyurethane.
4. The sleeve grouting material for prefabricated components according to claim 1, wherein the thickening agent is cellulose ether.
The sleeve grouting material for prefabricated components according to claim 8, wherein the thickener is hydroxyethyl methyl cellulose ether, hydroxypropyl methyl cellulose ether, and hydroxypropyl methyl cellulose ether. One of them.
The sleeve grouting material for prefabricated components according to claim 1, wherein the toughening agent is methyl methacrylate-butadiene-styrene polymer, acrylonitrile-butadiene-styrene polymer , One of chlorinated polyethylene.
The method for preparing sleeve grouting material for prefabricated members according to any one of claims 1-10, characterized in that it comprises the following steps:

Step 1. Weigh each component in parts by weight;

Step 2. Mix the machine-made sand and molybdenum tailing sand in a mortar mixer for 3 to 5 minutes to obtain mixed sand;

Step 3. Add the thickener, toughening agent and expansion agent into the reaction kettle, add water, adjust the temperature to 20℃～40℃, stir for 10min～20min to make it dissolve;

Step 4. Under stirring, add the mixed sand and glass powder obtained in step 2 in step 3, and continue to stir for 20-30 minutes;

Step 5. Add polycarboxylic acid water-reducing agent and cement to the materials of step 4, stir uniformly for 10-20 minutes, and finally add the remaining amount of water to obtain sleeve grouting for prefabricated components.