CN113651590B

CN113651590B - Building leakage-stopping composite material and using method thereof

Info

Publication number: CN113651590B
Application number: CN202111130747.5A
Authority: CN
Inventors: 滕鑫
Original assignee: East China University of Science and Technology
Current assignee: East China University of Science and Technology
Priority date: 2021-09-26
Filing date: 2021-09-26
Publication date: 2022-04-19
Anticipated expiration: 2041-09-26
Also published as: CN113651590A

Abstract

The invention provides a building leaking stoppage composite material, which consists of active magnesium oxide, rubber particles, water-based acrylate emulsion, a water-based curing agent, magnesium bicarbonate and magnesium chloride. The concrete has the advantages of low shrinkage rate of a consolidation material body, good water resistance, strong crack deformation resistance, high fault tolerance of a formula and the like.

Description

Building leakage-stopping composite material and using method thereof

Technical Field

The invention belongs to the field of building materials, and particularly relates to a building leakage-blocking composite material.

Background

The plugging material can solve the technical problems of repairing cracks and plugging of buildings such as concrete and the like. The plugging agent in the building industry is widely applied to plugging of buildings such as tunnels, bridges, houses and the like in complex construction environments such as underground, underwater, quicksand and the like, water stopping, rush repair, pouring, water proofing, bonding and the like.

Taking the traffic field as an example, tunnel engineering has become an important component in road installations. At present, the total length of the Chinese road tunnel exceeds 2 kilometers. Whether a newly built tunnel or a tunnel which is put into operation, the vault of a tunnel lining is hollow and water leakage of a tunnel shield is a common problem which affects the quality and the service life of tunnel engineering.

The plugging material has the performances of rapid condensation, hardening, substrate material adhesion and the like in a water environment or an air environment, and has the functions of plugging cracks, improving the overall strength of the structure and the like. At present, building plugging materials in the market are short and long, some building plugging materials are low in bonding strength and easy to crack, some building plugging materials are poor in waterproof effect and need to be protected by other waterproof materials, some building plugging materials are good in bonding strength but long in solidification time, some building plugging materials are too high in cost and not suitable for being used in a large range, and the use of the plugging materials is limited by various problems.

Chinese patent CN107935516A discloses a micro-expansive grouting material for grouting arch crown with a mold of a tunnel lining, which is prepared by adding water into 750-800 parts of a cementing component, 900-1350 parts of composite graded quartz sand, 100-150 parts of a graphene oxide modified mineral admixture, 8-10 parts of a volume stability regulator and 2-3 parts of an enhanced water reducing agent, and mixing and stirring the components, wherein the water-material ratio is 0.16-0.19. The graphene oxide modified mineral admixture described in the patent is prepared by dispersing graphene oxide in water, adding silica fume and fly ash, stirring and drying. The volume stability regulator is prepared by uniformly mixing a concrete expanding agent, red brick powder and super absorbent resin SAP according to the mass ratio of 6:3: 1. The micro-expansion grouting material used for grouting with a mold at the arch crown of the tunnel lining has the plastic expansion rate of 0.6-1.2 percent and has the following defects: 1, the preparation method is complex and has high cost. 2, the loss of fluidity of the alloy is larger for 90min by using mineral admixture. 3, although the concrete lining material has certain micro-expansibility, the compression strength, the breaking strength and the bonding strength with concrete are low, the surplus value of the bonding strength with the concrete is not high, and the later-stage bonding performance with the lining concrete is difficult to estimate.

Chinese patent CN107686300A discloses a micro-expansion grouting material for filling tunnel lining, which is prepared from the following components in parts by weight: 35-50 parts of common cement, 5-8 parts of microbeads, 3-5 parts of silica fume, 4-6 parts of an expanding agent, 35-45 parts of quartz sand, 1-2 parts of a water reducing agent, 0.5-1.5 parts of a retarder, 0.1-0.3 part of a water-retaining agent, 0.2-0.4 part of an early strength agent, 0.2-0.3 part of a plastic expanding agent, 0.1-0.3 part of redispersible latex powder and 0.1-0.3 part of a defoaming agent. It has the following disadvantages: 1, the formula of the invention has high cost and is inconvenient for construction engineering application; 2, the retarder is contained in the formula, so that the strength of the grouting material is difficult to control for 12 hours, and the mechanical strength of the grouting material for 12 hours is difficult to ensure; 3, in the performance index detection results of the embodiment, the strength of 7d is low, the surplus value of the bonding strength with concrete is not high, and the later-stage bonding performance of the configured micro-expansion grouting material and lining concrete is difficult to estimate; 4, in the performance index detection results of the examples, the detection of the combination performance of the micro-expansion grouting material and the RPC grouting pipe is lacked.

The inorganic waterproof plugging material can be used for treating the shield water leakage problem. The existing inorganic waterproof plugging material usually takes cement as a main component, and the cement system is promoted to achieve an ideal plugging effect by adding a coagulant and a hardening accelerator. For example, Chinese patent 201610231241.6 discloses a fast-curing waterproof plugging material capable of being constructed at low temperature, which is prepared from the following raw materials, by weight, 45-68 parts of fast-hardening cement, 18-42 parts of aggregate, 0.5-1 part of dispersant, 0.3-1.5 parts of toughening agent, 0.5-1.2 parts of adhesion promoter, 2-7 parts of special auxiliary agent, 0.5-2.3 parts of coagulant and 0.6-2.2 parts of reinforcing agent. The formula of the plugging material disclosed in Chinese patent 20181133867.4 comprises: 60-90 parts of quick-setting cement component, 0-35 parts of ordinary cement component, 1-7 parts of expansion component, 0-1 part of retarder, 0.5-1 part of water reducing agent, 0.5-1 part of powdery defoamer, 0.5-1 part of tackifying and water-retaining agent and 0.5-1 part of rubber powder. At present, organic plugging materials are rarely used for repairing water leakage cracks of tunnel shields.

The epoxy resin material has excellent mechanical property, chemical corrosion resistance and bonding property, and is widely applied to the industrial fields of waterproof anticorrosive paint, epoxy floor paint, electronic encapsulating material, adhesive and the like. It is also commonly used in the field of construction engineering for reinforcing and reinforcing concrete. Early epoxy resin grouting materials were mainly modified epoxy resin grouting materials such as furfural acetone. The material is suitable for reinforcing and reinforcing cracks and structural bodies and high-performance plugging maintenance in an open water-free environment, cannot be directly used for grouting and plugging in an open water and water burst environment, and greatly limits the application of epoxy resin in the field of plugging materials.

In conclusion, the prior art of the plugging material has the following problems and disadvantages;

(1) the synergistic effect of the various additives added is poor, resulting in poor long-term bonding of the plugging material to the base material (concrete material or rock material) to be plugged.

(2) The setting and curing of the plugging material are usually exothermic reactions, the temperature is reduced after the setting, and the volume shrinkage easily causes the cracking of the bonding surface, thereby affecting the plugging effect.

(3) And some additives (such as accelerating agent and hardening accelerator) are used for achieving the purpose of shortening the setting time, and the later strength of the material is sacrificed, so that the plugging material gradually generates internal cracks, and the service life is influenced.

(4) The expansion agent is generally completely expanded in the plasticity stage of the grouting material, basically has no expansion after the grouting material is hardened, cannot ensure the expansion amount of the grouting material in the later curing stage, and is easy to continuously shrink due to the reasons of expansion with heat and contraction with cold, continuous hydration and the like to form cracks after curing.

(5) The faster the plugging agent is coagulated, the greater the influence on the workability, and particularly the difficulty in balancing the relationship between the setting accelerator and the hardening accelerator during the setting adjustment process.

Therefore, the leakage stoppage of the building engineering of the tunnel, the underground building below the underground water level, the underwater building and the like in the prior art is easy to cause repeated leakage, and can only treat the symptoms and not the root causes. It is necessary to redesign the lost circulation material system to solve the above problems.

Disclosure of Invention

The invention provides a building leakage-stopping composite material which comprises the following components in parts by weight:

10-20 parts of active magnesium oxide, 5-15 parts of rubber particles, 15-25 parts of water-based acrylate emulsion, 2-5 parts of water-based curing agent, 0.5-1 part of magnesium bicarbonate and 5-10 parts of magnesium chloride.

Preferably, the rubber particles are obtained by crushing waste rubber raw materials, and the mesh number is more than or equal to 20 meshes.

Preferably, the aqueous curing agent is a water-soluble polyamine epoxy curing agent, including diethylenetriamine and triethylene tetramine.

Preferably, the ratio of the usage amount of the water-based curing agent to the water-based acrylate emulsion is 1: 5 to 8.

Preferably, the ratio of the amount of the magnesium chloride to the amount of the active magnesium oxide is 1: 1.8 to 2.2.

Preferably, the cement is portland cement.

Preferably, the iodine absorption value of the active magnesium oxide is more than 80 g/L, and the mesh number is more than or equal to 120 meshes (namely, the maximum particle size is less than or equal to 125 micrometers).

The invention further provides a use method of the building leaking stoppage composite material, which comprises the following steps:

step 1, according to parts by weight, taking 2-5 parts of aqueous curing agent, 15-25 parts of aqueous acrylate emulsion, 5-10 parts of magnesium chloride, 0.5-1 part of magnesium bicarbonate and 2-5 parts of water, and uniformly stirring to obtain a mixture A;

step 2, adding 10-20 parts by weight of active magnesium oxide and 5-15 parts by weight of rubber particles into the mixture A, and uniformly stirring to obtain a mixture B;

step 3, rapidly and uniformly stirring 1 part of the mixture B, 0-2 parts of cement and 0.2-1 part of water by weight to obtain a mixture C;

and 4, quickly injecting the mixture C obtained in the step 3 into a crack to be blocked while stirring.

The water added in the step 1 mainly plays a role of dispersing agent and promoting mixing, and the amount of the added water can be determined according to the total amount of the fed materials, so as to ensure that the components can be fully mixed into slurry. And (3) adjusting the water quantity added in the step (3) according to the water seepage condition of the cracks needing to be blocked besides the total quantity of the added materials, wherein the using amount of added water is properly reduced in the construction environment with higher water seepage quantity.

Preferably, the feeding sequence of the step 1 is to mix the magnesium chloride, the magnesium bicarbonate and water, then add the water-based acrylate emulsion, and finally add the water-based curing agent.

Preferably, in the step 2, the active magnesium oxide and the rubber particles are uniformly mixed and then added to the mixture a.

Preferably, the crack to be plugged is flushed with a high-pressure water flow before the step 4.

In the technical scheme provided by the invention, the cement is a low-cost construction material, is mixed with the building leakage-stopping composite material for use, and can provide main physical strength for a consolidated material body after the consolidation of the plugging material. The grade of the cement used in the invention is not limited, and the cement can be ordinary portland cement or alumina cement, and the like. If cement is not used, the plugging material is completely used for plugging cracks, a good plugging effect can be achieved, however, the material cost is too high, and the physical strength may not meet the actual requirement.

The invention adopts the water-based epoxy curing agent which can perform curing reaction with carboxyl in the acrylate, so as to enhance the internal acting force of the consolidation material body and be beneficial to improving the bonding property and the durability of the consolidation material body in a humid environment. However, since the price of the curing agent and the acrylic ester is high, the addition amount thereof should be controlled according to the working environment. The addition amount of the curing agent and the acrylic ester can be increased under severe construction environment or cracks which are difficult to repair.

The rubber particles are used for replacing the traditional sand material or aggregate, so that enough elasticity can be provided for the consolidated material body after the plugging material is consolidated. However, the mutual adhesion between the rubber particles and the cement is not satisfactory. The rubber particles are added in the invention, so that the elasticity of the consolidation material body can be improved, and the mutual fusion of the epoxy resin and the cement is facilitated. The addition amount of the rubber particles is determined according to the addition amount of the acrylate.

The magnesium bicarbonate releases carbon dioxide gas after being heated, micro bubbles can be formed in the solidified material body, and the shrinkage rate of the solidified material body is reduced. And when the magnesium bicarbonate is added too much, the generated micro bubbles are too much and are easy to gather to form large bubbles, so that the strength of the consolidation material body is reduced, and when the magnesium bicarbonate is added too little, the effect cannot be achieved.

The quick-drying cement is replaced by the active magnesium oxide and the magnesium chloride, the quick-drying cement can be better contained with rubber particles, the compressive strength of the consolidation material body is improved, the initial strength of the consolidation initial stage can be provided, the construction difficulty is reduced, and meanwhile, the magnesium hydroxide after the decomposition of the magnesium bicarbonate can form a stable gel structure with the active magnesium oxide and the magnesium chloride, so that the shrinkage rate of the consolidation material body can be reduced in a humid environment. However, too much addition may affect the useful life of the consolidated material body.

The beneficial effects of the invention include:

1. low shrinkage of the consolidation material

By the optimized compounding of the active magnesium oxide, the rubber particles, the water-based acrylate emulsion, the water-based curing agent, the magnesium bicarbonate and the magnesium chloride, the provided plugging composite material has the shrinkage compensation performance in the consolidation process, and the shrinkage rate of the consolidated body is lower.

2. The water resistance is good.

The plugging material provided by the invention combines the advantages of the organic plugging material and the inorganic plugging material, has high underwater bonding strength, and can be used for working conditions with large amount of water seepage.

3. Strong ability of resisting crack and deformation

The added rubber particles and the internal microporous structure enable the solidified body to have certain elasticity, so that the external stress applied to the crack can be absorbed, and secondary cracking of the plugging part is avoided. Is particularly suitable for building facilities such as roads, bridges, tunnels and the like.

4. Reasonable raw material compatibility

The aqueous acrylate emulsion is cured and dehydrated to form a film, micropores on the surface of rubber particles can be sealed, microbubbles formed by carbon dioxide can be sealed, and the defects of water seepage, corrosion and the like caused by the fact that the micropores are communicated with each other to form capillaries can be avoided while certain structural elasticity is provided.

5. The fault tolerance of the formula is higher

The concrete material has no precise requirement on the proportion of various raw materials, and a solidification material body with smaller shrinkage can be obtained within the proportion range of the formula, so that the requirement of rapid construction under complex working conditions can be met, and the construction quality is improved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram showing the preparation of a sample for underwater adhesion strength measurement in the example of the present invention. A mould 1, a soaked substrate 3, a space 2 into which the mixture C is to be injected.

Detailed Description

In the following examples, the aqueous acrylate emulsion used was BASF joncryl 631 or BASF watersoxy 1422; the used waterborne epoxy curing agent containing amino is a commercially available triethylene tetramine waterborne epoxy curing agent; the cement used was P42.5R portland cement; the active magnesium oxide is produced by national magnesium industry (Huaian) limited company, the iodine absorption value is 80-120 g/L, and the mesh number is more than or equal to 120 meshes. The rubber particles are obtained by crushing waste rubber tires serving as raw materials, and the mesh number of the rubber particles is more than or equal to 20 meshes.

The examples, where specific techniques or conditions are not indicated, can be performed according to techniques or conditions described in literature in the art, or according to product specifications, or according to common general knowledge in the art. The reagents or instruments used are not indicated by manufacturers, and all are conventional products which can be obtained by purchasing through normal channels.

Example 1

Step 1, according to parts by weight, taking 2 parts of aqueous curing agent, 15 parts of aqueous acrylate emulsion, 5 parts of magnesium chloride, 0.5 part of magnesium bicarbonate and 2 parts of water, and uniformly stirring to obtain a mixture A. The adding sequence is that the magnesium chloride and the magnesium bicarbonate are mixed with water, then the mixture is mixed with the water-based acrylic ester emulsion, and finally the water-based curing agent is added.

And 2, adding 10 parts of active magnesium oxide and 5 parts of rubber particles into the mixture A by weight, and uniformly stirring to obtain a mixture B.

And 3, rapidly and uniformly stirring 1 part of the mixture B and 0.2 part of water in parts by weight to obtain a mixture C.

And 4, quickly injecting the mixture C obtained in the step 3 into a mold while stirring. After curing for 24 hours, the mold was removed to obtain a sample.

And 5, measuring the shrinkage rate.

Prism samples of 150 mm x 550 mm were prepared according to the above steps 1 to 4. According to GB/T50081-2019 test method Standard for physical and mechanical Properties of concrete, shrinkage of 28 days after demolding is measured.

And 6, measuring the compressive strength.

Prism samples of 150 mm x 150 mm were prepared according to the above steps 1 to 4. According to GB/T50081-2019 'test method standard of concrete physical and mechanical properties', the compressive strength of 28 days after demoulding is measured.

And 7, measuring the elastic modulus under static pressure.

Prism samples of 150 mm x 300 mm were prepared according to the above steps 1 to 4. According to GB/T50081-2019 'test method standard of concrete physical and mechanical properties', the static compression elastic modulus of 28 days after demoulding is measured.

And 8, measuring the underwater bonding rupture strength.

As shown in FIG. 1, a matrix 3 having a size of 150 mm by 250 mm was produced from portland cement, and cured for 28 days or more. The substrate 3 is soaked in water for more than 12 hours. Mixture C was prepared according to this example, steps 1 through 3. The mould 1 used has internal dimensions of 150 mm x 550 mm, the soaked substrates 3 being placed on both sides of the mould 1, leaving a space 2 in the middle, the volume of the space 2 being at least 50 mm x 150 mm. The mixture C was poured into the space 2, immersed in water to cure for 24 hours, and then demolded to obtain a sample having dimensions of 150 mm × 550 mm. Curing for 28 days in an environment with 25 ℃ and relative humidity above 90%. The flexural strength is determined by referring to the method described in chapter 10 of GB/T50081-2019 test method Standard for physical and mechanical Properties of concrete.

Example 2

Step 1, according to parts by weight, taking 5 parts of aqueous curing agent, 25 parts of aqueous acrylate emulsion, 5 parts of magnesium chloride, 1 part of magnesium bicarbonate and 5 parts of water, and uniformly stirring to obtain a mixture A.

And 2, mixing 9 parts of active magnesium oxide and 10 parts of rubber particles in parts by weight, adding the mixture into the mixture A, and uniformly stirring to obtain a mixture B.

And step 3, rapidly and uniformly stirring 1 part of the mixture B, 2 parts of Portland cement with the label of 42.5R and 1 part of water in parts by weight to obtain a mixture C.

Shrinkage, compressive strength, static compression modulus of elasticity and underwater bond flexural strength were measured 28 days after demolding as described in example 1.

Example 3

Step 1, taking 3 parts of aqueous curing agent, 20 parts of aqueous acrylate emulsion, 9 parts of magnesium chloride, 0.8 part of magnesium bicarbonate and 4 parts of water by weight, and uniformly stirring to obtain a mixture A.

And 2, mixing 20 parts by weight of active magnesium oxide and 8 parts by weight of rubber particles, adding the mixture into the mixture A, and uniformly stirring to obtain a mixture B.

And step 3, rapidly and uniformly stirring 1 part of the mixture B, 1 part of Portland cement with the label of 42.5R and 0.5 part of water in parts by weight to obtain a mixture C.

Example 4

Step 1, taking 4 parts of aqueous curing agent, 20 parts of aqueous acrylate emulsion, 9 parts of magnesium chloride, 1 part of magnesium bicarbonate and 3 parts of water by weight, and uniformly stirring to obtain a mixture A.

And 2, mixing 16 parts of active magnesium oxide and 5 parts of rubber particles in parts by weight, adding the mixture into the mixture A, and uniformly stirring to obtain a mixture B.

And step 3, rapidly and uniformly stirring 1 part of the mixture B, 1.2 parts of Portland cement with the label of 42.5R and 0.7 part of water in parts by weight to obtain a mixture C.

The test results of examples 1 to 4 are shown in table 1 below.

Table 1 test results of performance test of samples obtained in each example after 28 days of curing

	Example 1	Example 2	Example 3	Example 4
					Shrinkage (%)	1.53	1.98	1.65	1.81
Compressive strength (MPa)	10.2	19.7	13.5	14.8
					Static compression modulus of elasticity (Jipa)	3.98	3.17	2.88	3.53
Breaking strength of underwater adhesive (MPa)	2.89	4.02	3.51	3.77

The experimental results show that the building leaking stoppage composite material provided by the invention is low in shrinkage rate, excellent in underwater bonding performance and high in fault tolerance of raw material proportion, and is particularly suitable for scenes such as repeated leaking building crack leaking stoppage construction and the like.

While there have been shown and described what are at present considered the fundamental principles and essential features of the invention and its advantages, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing exemplary embodiments, but is capable of other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. The building leakage-stopping composite material is characterized by comprising a mixture B consisting of the following components in parts by weight: 10-20 parts of active magnesium oxide, 5-15 parts of rubber particles, 15-25 parts of water-based acrylate emulsion, 2-5 parts of water-based curing agent, 0.5-1 part of magnesium bicarbonate and 5-10 parts of magnesium chloride; the cement-based composite material also comprises cement, wherein the cement is used in an amount of 0-2 parts by weight per 1 part of the mixture B.

2. The building plugging composite material of claim 1, wherein the activated magnesium oxide has an iodine absorption value of greater than 80 g/l and a mesh number of 120 mesh or greater.

3. The building plugging composite material of claim 1, wherein the aqueous curing agent is a water-soluble polyamine epoxy curing agent.

4. The building plugging composite material of claim 3, wherein the water-soluble polyamine epoxy hardener is diethylenetriamine or triethylenetetramine.

5. The building plugging composite material of claim 1, wherein the ratio of the water-based curing agent to the water-based acrylate emulsion is 1: 5-8 by weight.

6. The building plugging composite material of claim 1, wherein the rubber particles are obtained by crushing waste rubber raw materials, and the mesh number of the rubber particles is greater than or equal to 20 meshes.

7. The use method of the building lost circulation composite material as defined in claim 1, which is characterized by comprising the following steps: step 1, according to parts by weight, taking 2-5 parts of aqueous curing agent, 15-25 parts of aqueous acrylate emulsion, 5-10 parts of magnesium chloride, 0.5-1 part of magnesium bicarbonate and 2-5 parts of water, and uniformly stirring to obtain a mixture A; step 2, adding 10-20 parts by weight of active magnesium oxide and 5-15 parts by weight of rubber particles into the mixture A, and uniformly stirring to obtain a mixture B; step 3, rapidly and uniformly stirring 1 part by weight of the mixture B, 0-2 parts by weight of cement and 0.2-1 part by weight of water to obtain a mixture C; and 4, rapidly injecting the mixture C obtained in the step 3 into a crack to be blocked while stirring.

8. The use method of the building leakage-stopping composite material as claimed in claim 7, wherein the feeding sequence of the step 1 is to mix the magnesium chloride and the magnesium bicarbonate with water, then add the water-based acrylate emulsion, and finally add the water-based curing agent.

9. The method for using the building leakage blocking composite material as described in claim 7, wherein the step 2 is to mix the active magnesium oxide and the rubber particles uniformly and then add the mixture to the mixture A.