Preparation method of chemically filled foam modified fiber rubber concrete

Abstract

The invention relates to a preparation method of chemically filled foam modified fiber rubber concrete. The preparation method comprises the following steps: preparing quantitative foam by using a foaming agent; the preparation method comprises the following steps: dissolving tetraethoxysilane in absolute ethyl alcohol to form a TEOS-ethanol solution; soaking the foam sample in a TEOS-ethanol solution, stirring, and pouring a hydrolysis catalyst to obtain modified foam; adding cement, fly ash, rubber particles, polypropylene fibers and water into a stirrer, fully stirring, and uniformly mixing to obtain cement mortar; adding the modified foam into cement mortar, and uniformly stirring to obtain fiber rubber foam concrete mortar; and pouring the mixture into a mold for molding, demolding, and curing to the age to obtain the product. According to the method, the compressive strength and the deformation resistance of the foam can be enhanced, and the thermal isolation performance and the fire resistance of the foam can be remarkably improved; the filling of the silicon dioxide particles not only can improve the stability of the foam structure on the microscopic level, but also can prolong the service life of the concrete by improving the hardness and wear resistance of the material.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete preparation, and particularly relates to a preparation method of chemically filled foam-modified fiber rubber concrete. Background Art

[0002] With the continuous growth of the construction industry's demand for high-performance, lightweight, energy-saving and environmentally friendly materials, traditional concrete has certain limitations in many aspects. Concrete usually has a relatively high density and thermal conductivity, which restricts its application in some special environments. For example, in a high-temperature environment, the heat insulation performance of concrete is poor, resulting in large fluctuations in the internal temperature of buildings, increasing energy consumption and air-conditioning load; while in a low-temperature environment, concrete is prone to cause indoor heat loss, increasing the heating demand.

[0003] Traditional foam concrete has a large number of pores inside. Although it has good heat insulation and sound insulation properties, its compressive strength is relatively low and it is difficult to withstand large external pressures or heavy loads, resulting in limitations in its application in load-bearing structures. Foam is a thermodynamically unstable system. Under the action of gravity, migration-fusion-drainage behavior (i.e., foam disproportionation phenomenon) occurs, making the liquid film of the foam thinner and the stability worse, affecting the stability and durability of the structure. Under the requirements of multiple properties such as high strength, fire resistance, heat insulation, and sound insulation, the application of traditional foam concrete still faces certain challenges. Therefore, it is of great practical significance to seek a preparation method for concrete with excellent properties such as high strength, fire resistance, heat insulation, and sound insulation. Summary of the Invention

[0004] The purpose of the present invention is to provide a preparation method of chemically filled foam-modified fiber rubber concrete. By introducing silica particles inside the foam, this method can not only effectively enhance the compressive strength and anti-deformation ability of the foam, but also significantly improve its heat insulation performance and fire resistance; in addition, the filling of silica particles can not only improve the stability of the foam structure at the microscopic level, but also extend the service life of the concrete by increasing the hardness and wear resistance of the material.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is: a preparation method of chemically filled foam-modified fiber rubber concrete, comprising the following steps:

[0006] A preparation method of chemically filled foam-modified fiber rubber concrete, comprising the following steps:

[0007] S1. Take a foaming agent and water, stir them with a diluent in a container, start a small foaming machine to produce foam, and then take out the prepared foam sample for standby;

[0008] S2, dissolving tetraethyl orthosilicate in anhydrous ethanol to form a TEOS-ethanol solution with a concentration of 11%-12%;

[0009] S3, soaking the foam sample prepared in step S1 in the TEOS-ethanol solution prepared in step S2 and stirring, and then pouring a hydrolysis catalyst, so that TEOS undergoes a hydrolysis reaction inside the foam to obtain a modified foam; the hydrolysis catalyst is a mixture of deionized water and ammonia water or a mixture of deionized water and hydrochloric acid;

[0010] S4, adding cement, fly ash, rubber particles, polypropylene fiber and water into a mixer and stirring thoroughly to obtain cement mortar;

[0011] S5. Add the modified foam prepared in step S3 to the cement mortar prepared in step S4, and stir evenly to obtain fiber rubber foam concrete mortar; pour it into a standard mold for molding, demoulding, and place it in a standard curing room for curing to the age.

[0012] Preferably, in step S1, the mass component ratio between the foaming agent and water is 1:50; and the bulk density of the prepared foam sample is 30 g / L.

[0013] Preferably, in step S2, the mass component ratio between tetraethyl orthosilicate and anhydrous ethanol is 1:9.

[0014] Preferably, in step S3, the mass component ratio between the foam sample and the TEOS-ethanol solution is 51:30.

[0015] Preferably, in step S3, the hydrolysis catalyst is a mixture of 4 parts of deionized water and 1 part of aqueous ammonia; or the hydrolysis catalyst is a mixture of 4 parts of deionized water and 1 part of hydrochloric acid.

[0016] Preferably, in step S4, the cement mortar is prepared from 550-570 parts of cement, 130-140 parts of fly ash, 90-110 parts of rubber particles, 1 part of 2-5 mm fiber, and 210-260 parts of water.

[0017] Preferably, in step S5, 95% of the prepared modified foam is added to 90% of the prepared cement mortar.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] In the present invention, tetraethyl orthosilicate (TEOS) is used as a precursor during the foaming process, hydrolyzing and condensing inside the pores to form silica particles, which fill the pores and can act as a reinforcing phase. It can effectively improve the compressive strength and deformation resistance of the foam. The structure of the foam itself is relatively fragile. After filling with silica, the particles can bear part of the externally applied pressure, preventing excessive deformation and collapse of the pores. Silica has a low thermal conductivity. After being filled into the foam, it can further reduce the heat conduction ability of the foam. At the same time, the silica particles can interfere with the heat transfer path inside the foam, making it more difficult for heat to pass through the foam. In addition, silica can increase the hardness and wear resistance of the foam, making the surface of the filled foam more solid. When subjected to external forces such as friction and scratching, it can better maintain its shape and performance, effectively improving the comprehensive performance of fiber rubber concrete. Detailed implementation manners

[0020] The present invention will be further described in detail below in conjunction with embodiments.

[0021] Embodiment 1

[0022] A preparation method of fiber rubber concrete modified by chemically filled foam includes the following steps:

[0023] S1. Take 1 part of foaming agent and 50 parts of water and stir them in a container as a diluent. Start a small foam generator to produce foam, and then take out the prepared foam sample for standby;

[0024] S2. Dissolve 3 parts of tetraethyl orthosilicate in 27 parts of absolute ethanol to form a TEOS-ethanol solution with a concentration of 11.6%;

[0025] S3. Immerse the foam sample prepared in step S1 in the TEOS-ethanol solution prepared in step S2 and stir. Then pour in 4 parts of deionized water and 1 part of ammonia water as a hydrolysis catalyst (alkaline), and TEOS undergoes a hydrolysis reaction inside the foam to obtain modified foam;

[0026] S4. Add 560 parts of PO42.5 ordinary Portland cement, 140 parts of fly ash, 100 parts of rubber particles, 1 part of 3mm polypropylene fiber, and 250 parts of water to a mechanical mixer and stir well to mix evenly to obtain cement mortar;

[0027] S5. Add the modified foam prepared in step S3 to the cement mortar prepared in step S4, stir evenly to obtain fiber rubber foam concrete mortar; pour it into a standard mold for molding, demold after 24 hours, and cure it in a standard curing room for 28 days to obtain.

[0028] Embodiment 2

[0029] A preparation method of chemically filled foam-modified fiber rubber concrete, comprising the following steps:

[0030] S1. Take 1 part of foaming agent and 50 parts of water, stir them in a container as diluent, start a small foaming machine to form foam with a bulk density of 30 g / L, and then take out the prepared foam sample for standby;

[0031] S2. Dissolve 3 parts of tetraethyl orthosilicate in 27 parts of absolute ethanol to form a TEOS-ethanol solution;

[0032] S3. Immerse the foam sample prepared in step S1 in the TEOS-ethanol solution prepared in step S2 and stir, then pour in 4 parts of deionized water and 1 part of hydrochloric acid as a hydrolysis catalyst (acidic), and TEOS undergoes a hydrolysis reaction inside the foam to obtain modified foam;

[0033] S4. Add 560 parts of PO42.5 ordinary Portland cement, 140 parts of fly ash, 100 parts of rubber particles, 1 part of 3-mm polypropylene fiber, and 250 parts of water to a mechanical mixer, stir well, and mix evenly to obtain cement mortar;

[0034] S5. Add the modified foam prepared in step S3 to the cement mortar prepared in step S4, stir evenly to obtain fiber rubber foam concrete mortar; pour it into a standard mold for molding, demold after 24 hours, and place it in a standard curing room for curing for 28 days to obtain.

[0035] Control example

[0036] Preparation method of traditional foam concrete: Take 1 part of foaming agent and 50 parts of water, dilute and stir them in a dilution bottle, start a small foaming machine to prepare foam, and then take out the prepared foam for standby; successively add 560 parts of PO42.5 ordinary Portland cement, 140 parts of fly ash, 100 parts of rubber particles and 1 part of 3-mm polypropylene fiber and 250 parts of water to a mechanical mixer, stir well to ensure uniform mixing; then add the foam to the cement mortar, stir evenly, pour the fiber rubber foam concrete mortar into a standard mold for molding, demold after 24 hours, and place it in a standard curing room for curing for 28 days.

[0037] Table 1 Performance test data of traditional foam concrete and foam-modified fiber rubber concrete

[0038]

[0039] As can be seen from Table 1, the foam-modified fiber rubber concrete of the present invention has effectively enhanced compressive strength, significantly decreased thermal conductivity, significantly improved the thermal insulation performance of traditional foam concrete, and the fire resistance limit has increased by about 0.9 - 1 h. Thus, the strength, fire resistance, and heat insulation performance of foam concrete are comprehensively improved.

[0040] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be covered by the protection scope of the present invention.

Claims

1. A preparation method of chemically filled foam-modified fiber rubber concrete, characterized in that It includes the following steps: S1. Take a foaming agent and water, stir them in a container with a diluent, start a small foaming machine to produce foam, and then take out the prepared foam sample for standby; S2. Dissolve tetraethyl orthosilicate in absolute ethanol to form a TEOS-ethanol solution with a concentration of 11%-12%; S3. Immerse the foam sample prepared in step S1 in the TEOS-ethanol solution prepared in step S2 and stir, then pour in a hydrolysis catalyst, and TEOS undergoes a hydrolysis reaction inside the foam to obtain a modified foam; the hydrolysis catalyst is a mixture of deionized water and ammonia water or a mixture of deionized water and hydrochloric acid; S4. Add cement, fly ash, rubber particles, polypropylene fibers, and water to a mixer and stir well to obtain a cement mortar by mixing evenly; S5. Add the modified foam prepared in step S3 to the cement mortar prepared in step S4, stir evenly to obtain a fiber rubber foam concrete mortar; pour it into a standard mold for molding, demolding, and place it in a standard curing room for curing until the age, then it can be obtained.

2. The preparation method of a fiber rubber concrete modified by chemical filling foam according to claim 1, characterized in that, In step S1, the mass component ratio between the foaming agent and water is 1:50; the bulk density of the prepared foam sample is 30 g / L.

3. A preparation method of fiber rubber concrete modified by chemical filling foam according to claim 1, characterized in that, In step S2, the mass component ratio between tetraethyl orthosilicate and absolute ethanol is 1:

9.

4. A method for preparing fiber rubber concrete modified by chemical filling foam according to claim 1, characterized in that, In step S3, the mass component ratio between the foam sample and the TEOS-ethanol solution is 51:

30.

5. A preparation method of fiber rubber concrete modified by chemical filling foam according to claim 1, characterized in that, In step S3, the hydrolysis catalyst is a mixture of 4 parts of deionized water and 1 part of ammonia water; or the hydrolysis catalyst is a mixture of 4 parts of deionized water and 1 part of hydrochloric acid.

6. A preparation method of chemically filled foam-modified fiber rubber concrete according to claim 1, characterized in that, In step S4, the cement mortar is prepared from 550-570 parts of cement, 130-140 parts of fly ash, 90-110 parts of rubber particles, 1 part of 2-5 mm fibers, and 210-260 parts of water.

7. A preparation method of chemically filled foam modified fiber rubber concrete according to claim 1, characterized in that In step S5, 95% of the prepared modified foam is added to 90% of the prepared cement mortar.

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