Flame-retardant spraying rapid-hardening waterproof inorganic guniting material and preparation method thereof

Abstract

The invention relates to the technical field of coal mine safety protection and building materials, in particular to a flame-retardant spraying rapid-hardening waterproof inorganic guniting material and a preparation method thereof. Comprising the following components in parts by weight: 40-80 parts of cement, 10-30 parts of fine aggregate, 10-30 parts of coarse aggregate, 10-20 parts of magnesium-aluminum hydrotalcite, 5-14 parts of a flame-retardant waterproof functional component, 1-2 parts of a dry powder accelerator and 50-80 parts of water. Compared with the prior art, when the obtained slurry is sprayed to the wall face of the well wall of a mine, the flame-retardant and waterproof performance is excellent, the slurry can be used for a long time, the windproof and waterproof effects of the well wall are enhanced, the supporting effect is further enhanced, the manufacturing process is simple, and the slurry can be applied to the field of coal mines on a large scale.

Description

Technical Field

[0001] The invention relates to the field of coal mine safety protection technology and building material technology, and in particular to a flame retardant spray quick-setting waterproof inorganic spray grout and a preparation method thereof. Background Art

[0002] Coal mine shotcrete is a material used to fill the gaps in coal mine tunnels and shafts to improve the stability and safety of the tunnels and shafts. When mining underground, first use a drill to drill holes and place gunpowder according to technical requirements, and then blast with detonators to create a certain arch. According to the design requirements, use an anchor drill to drill holes again, install anchors, anchor cables, hang nets and other support technical requirements, and then immediately waterproof and windproof the four walls of the shed to increase strength and spray grout to prevent gravel from falling.

[0003] For example, CN102482153A discloses a method for preparing a sprayable hydraulic binder composition containing water, aggregate, hydraulic binder and accelerator as main components, wherein a component containing calcium silicate hydrate (CSH) is added before and / or at the nozzle.

[0004] For example, CN109890584A discloses a multi-component mortar system, which comprises component A and component B, wherein: component A comprises high-alumina cement, at least one setting inhibitor, at least one mineral filler and water, and component B comprises an initiator system for setting-inhibited high-alumina cement, at least one mineral filler and water. The multi-component mortar system is easy to use and suitable for repair and renovation and in particular for printing 3D structures.

[0005] However, the flame retardant and waterproof properties of the above-mentioned coal mine spraying materials are not good and still need to be improved. Therefore, there is an urgent need for an inorganic spraying material with good flame retardant properties and excellent waterproof properties. Summary of the invention

[0006] The purpose of the present invention is to overcome the poor flame retardancy and waterproofness of the coal mine spraying materials in the above-mentioned prior art and to propose a flame retardant spraying quick-setting waterproof inorganic spraying material and a preparation method thereof.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] The first aspect of the present invention provides a flame retardant spray quick-setting waterproof inorganic spray grout, comprising the following components in parts by weight: 40-80 parts of cement, 10-30 parts of fine aggregate, 10-30 parts of coarse aggregate, 10-20 parts of magnesium aluminum hydrotalcite, 5-14 parts of flame retardant and waterproof functional components, 1-2 parts of dry powder quick-setting agent, and 50-80 parts of water.

[0009] Preferably, the flame retardant and waterproof functional component is prepared by the following method:

[0010] Polyacrylamide and silicon carbide whisker are sequentially added to silica sol, and calcium oxide, steel fiber and sisal fiber are sequentially added after stirring, and flame retardant and waterproof functional components are obtained after ball milling.

[0011] Preferably, the mass ratio of the silica sol, silicon carbide whisker, calcium oxide, steel fiber, sisal fiber and polyacrylamide is 100:(5-15):(30-50):(20-30):(20-30):(5-10).

[0012] Preferably, the mass ratio of the silica sol, silicon carbide whisker, calcium oxide, steel fiber, sisal fiber and polyacrylamide is 100:(8-13):(35-45):(22-28):(22-28):(6-9).

[0013] Preferably, the stirring time is 4-10 hours.

[0014] Preferably, the stirring time is 5-8h.

[0015] Preferably, the ball milling time is 20-60 min, and the ball milling speed is 100-200 r / min.

[0016] Preferably, the ball milling time is 25-50 min, and the ball milling speed is 120-180 r / min.

[0017] Preferably, the length of the silicon carbide whisker is 10-50 μm, the diameter is 0.1-0.6 μm, and the particle size of the calcium oxide is 50-100 nm.

[0018] Preferably, the length of the silicon carbide whisker is 18-40 μm, the diameter is 0.2-0.4 μm, and the particle size of the calcium oxide is 60-90 nm.

[0019] Preferably, the cement is ordinary Portland cement PO42.5.

[0020] Preferably, the coarse aggregate is pebbles and crushed stones, and the particle size thereof is 5-10 mm.

[0021] Preferably, the fine aggregate is natural sand or artificial sand, and its particle size is 0.25-0.5 mm.

[0022] The second aspect of the embodiment of the present application provides a method for preparing the flame-retardant spray quick-setting waterproof inorganic spray grout, comprising the following steps:

[0023] S1, weigh cement, coarse aggregate and fine aggregate in proportion and mix them to form powder;

[0024] S2, sequentially adding magnesium aluminum hydrotalcite, flame retardant and waterproof functional components, dry powder accelerator and water to the powder, mixing evenly, and stirring at a speed of 100-400 rpm for 15 minutes to obtain a spraying material.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] Compared with the prior art, the present application utilizes flame retardant and waterproof functional components and magnesium aluminum hydrotalcite to synergistically improve the flame retardant and waterproof properties of inorganic spraying materials, wherein polyacrylamide is first adsorbed on the surface of silicon carbide whiskers and forms an adsorption layer with a certain thickness, and then the silicon carbide whiskers are dispersed in the silica sol through polyacrylamide. This pre-dispersion effect prevents the silicon carbide whiskers from aggregating with each other through van der Waals forces, so that they can be well dispersed in the inorganic spraying material. When flame retardant, the silicon carbide whiskers can form an oxide protective layer with flame retardant properties at high temperature, effectively isolating the fire source and flame retardant flame spread. Moreover, due to its uniform dispersion, the formed protective layer has uniform thickness and excellent fireproof performance. Due to the addition of calcium oxide, calcium oxide is combined with silicon carbide whiskers through the bonding effect of silica sol, and when the inorganic spraying material solidifies, calcium oxide and water can fully react to form calcium hydroxide, and further form a dense gel in the inorganic spraying material. The gel can fill the interface between the steel fiber and sisal fiber and the coarse aggregate or fine aggregate. When the steel fiber and sisal fiber fill the inorganic spraying material, no gap will be generated, thereby preventing the penetration of moisture. Moreover, this gel can form a stable crystalline product with cement, which better fills the gap between various aggregates or fibers, further preventing the entry of moisture. In addition, the steel fiber and sisal fiber simultaneously enhance the mechanical properties of the coating after the inorganic spraying material solidifies.

[0027] In addition, the present application also adds magnesium aluminum hydrotalcite, which is easily decomposed by heat, releasing a large amount of water and carbon dioxide, and absorbing heat to reduce the temperature of the combustion system. In addition, it can also dilute or block combustible gases, so it and the flame retardant functional components improve the flame retardant effect through a variety of flame retardant methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a flow chart of the preparation method of the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] For ease of understanding of the present application, the present application will be described more fully below by way of embodiments. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0031] For simplicity, the present application only explicitly discloses some numerical ranges. However, any lower limit can be combined with any upper limit to form an unclearly recorded range; and any lower limit can be combined with other lower limits to form an unclearly recorded range, and any upper limit can be combined with any other upper limit to form an unclearly recorded range. In addition, although not clearly recorded, each point or single value between the range endpoints is included in the range. Thus, each point or single value can be combined with any other point or single value as its own lower limit or upper limit or with other lower limits or upper limits to form an unclearly recorded range.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present application. The terms used herein in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. It should be noted that, unless otherwise stated, the term "and / or" used herein includes any and all combinations of one or more related listed items, and "above", "below" include the number, and the meaning of "multiple" in "one or more" is more than two.

[0033] Example 1

[0034] Reference Figure 1 As shown, this embodiment provides a method for preparing a flame retardant spray quick-setting waterproof inorganic spray grout, comprising the following steps:

[0035] Preparation of flame retardant and waterproof functional components:

[0036] To the silica sol, polyacrylamide and silicon carbide whiskers with a length of 40 μm and a diameter of 0.3 μm are added in sequence, and after stirring, calcium oxide with a particle size of 80 nm, steel fiber and sisal fiber are added in sequence, wherein the mass ratio of silica sol, silicon carbide whiskers, calcium oxide, steel fiber, sisal fiber and polyacrylamide is 100:10:40:25:25:8, and then ball milled at a speed of 150 r / min for 30 minutes.

[0037] Preparation of spraying material:

[0038] S1, weigh 60 parts of cement, 20 parts of crushed stone with a particle size of 10 mm, and 20 parts of natural sand with a particle size of 0.25 mm and mix them to form a powder;

[0039] S2, add 10 parts of magnesium aluminum hydrotalcite, 10 parts of flame retardant and waterproof functional components, 1 part of dry powder accelerator and 60 parts of water to the powder in sequence, mix well, and stir at a speed of 200 rpm for 15 minutes to obtain a spraying material.

[0040] Example 2

[0041] Reference Figure 1 As shown, this embodiment provides a method for preparing a flame retardant spray quick-setting waterproof inorganic spray grout, comprising the following steps:

[0042] Preparation of flame retardant and waterproof functional components:

[0043] To the silica sol, polyacrylamide and silicon carbide whiskers with a length of 40 μm and a diameter of 0.3 μm are added in sequence, and after stirring, calcium oxide with a particle size of 80 nm, steel fiber and sisal fiber are added in sequence, wherein the mass ratio of silica sol, silicon carbide whiskers, calcium oxide, steel fiber, sisal fiber and polyacrylamide is 100:10:40:25:25:8, and then ball milled at a speed of 150 r / min for 30 minutes.

[0044] Preparation of spraying material:

[0045] S1, weigh 80 parts of cement, 30 parts of crushed stone with a particle size of 10 mm, and 30 parts of natural sand with a particle size of 0.25 mm and mix them to form a powder;

[0046] S2, add 10 parts of magnesium aluminum hydrotalcite, 10 parts of flame retardant and waterproof functional components, 1 part of dry powder accelerator and 80 parts of water to the powder in sequence, mix well, and stir at a speed of 200 rpm for 15 minutes to obtain a spraying material.

[0047] Example 3

[0048] Reference Figure 1 As shown, this embodiment provides a method for preparing a flame retardant spray quick-setting waterproof inorganic spray grout, comprising the following steps:

[0049] Preparation of flame retardant and waterproof functional components:

[0050] To the silica sol, polyacrylamide and silicon carbide whiskers with a length of 40 μm and a diameter of 0.3 μm are added in sequence, and after stirring, calcium oxide with a particle size of 80 nm, steel fiber and sisal fiber are added in sequence, wherein the mass ratio of silica sol, silicon carbide whiskers, calcium oxide, steel fiber, sisal fiber and polyacrylamide is 100:10:40:25:25:8, and then ball milled at a speed of 150 r / min for 30 minutes.

[0051] Preparation of spraying material:

[0052] S1, weigh 40 parts of cement, 10 parts of crushed stone with a particle size of 10 mm, and 10 parts of natural sand with a particle size of 0.25 mm and mix them to form a powder;

[0053] S2, add 10 parts of magnesium aluminum hydrotalcite, 10 parts of flame retardant and waterproof functional components, 1 part of dry powder accelerator and 60 parts of water to the powder in sequence, mix well, and stir at a speed of 200 rpm for 15 minutes to obtain a spraying material.

[0054] Example 4

[0055] Reference Figure 1 As shown, this embodiment provides a method for preparing a flame retardant spray quick-setting waterproof inorganic spray grout, comprising the following steps:

[0056] Preparation of flame retardant and waterproof functional components:

[0057] Polyacrylamide and silicon carbide whiskers with a length of 40 μm and a diameter of 0.3 μm are added to the silica sol in sequence, and calcium oxide with a particle size of 80 nm, steel fiber and sisal fiber are added in sequence after stirring. The mass ratio of silica sol, silicon carbide whiskers, calcium oxide, steel fiber, sisal fiber and polyacrylamide is 100:8:38:23:28:8, and then ball milled at a speed of 150 r / min for 30 minutes.

[0058] Preparation of spraying material:

[0059] S1, weigh 60 parts of cement, 20 parts of crushed stone with a particle size of 10 mm, and 20 parts of natural sand with a particle size of 0.25 mm and mix them to form a powder;

[0060] S2, add 10 parts of magnesium aluminum hydrotalcite, 10 parts of flame retardant and waterproof functional components, 1 part of dry powder accelerator and 60 parts of water to the powder in sequence, mix well, and stir at a speed of 200 rpm for 15 minutes to obtain a spraying material.

[0061] Comparative Example 1

[0062] Compared with Example 1, most of the components are the same except that no flame retardant functional component is added.

[0063] Comparative Example 2

[0064] Compared with Example 1, most of the steps are the same except that magnesium aluminum hydrotalcite is not added.

[0065] Comparative Example 3

[0066] Compared with Example 1, most of them are the same, except that the flame retardant functional component is directly changed to silicon carbide whiskers.

[0067] Test Case

[0068] The slurries obtained from Examples 1 to 4 and Comparative Examples 1 to 3 were directly sprayed onto the surface of the test stone, and the coatings were obtained after solidification and their performance was tested.

[0069] The mechanical properties of the coating were tested according to GB / T 50081-2019, the fire rating and fire resistance of the coating were tested according to GB 50016-2014, and the waterproof rating of the concrete was tested according to GB55030-2022. The results are shown in Table 1 below.

[0070] Table 1 Mechanical properties of Examples 1 to 3 and Comparative Examples 1 to 3

[0071]

[0072] It can be seen from Table 1 that the mechanical excellence of the coating obtained by spraying the slurry obtained in the embodiment of the present application is far superior to that of the coating obtained in the comparative example, and the fire resistance grade of the coating can reach Class A, and its waterproof grade can reach P12. When the slurry obtained in the present application is sprayed onto the wall of the mine shaft, it has excellent flame retardant and waterproof properties, can be used for a long time, enhances the windproof and waterproof properties of the shaft wall, further enhances the support effect, and has a simple manufacturing process, and can be used on a large scale in the coal mining field.

[0073] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A flame retardant quick-setting waterproof inorganic spray grout, characterized in that: The invention comprises the following components in parts by weight: 40-80 parts of cement, 10-30 parts of fine aggregate, 10-30 parts of coarse aggregate, 10-20 parts of magnesium-aluminum hydrotalcite, 5-14 parts of flame retardant and waterproof functional components, 1-2 parts of dry powder quick-setting agent and 50-80 parts of water.

2. The flame-retardant quick-setting waterproof inorganic spray grout according to claim 1, characterized in that: The flame retardant and waterproof functional component is prepared in the following manner: Polyacrylamide and silicon carbide whisker are sequentially added to silica sol, and calcium oxide, steel fiber and sisal fiber are sequentially added after stirring, and flame retardant and waterproof functional components are obtained after ball milling.

3. The flame-retardant quick-setting waterproof inorganic spray grout according to claim 2, characterized in that: The mass ratio of the silica sol, silicon carbide whisker, calcium oxide, steel fiber, sisal fiber and polyacrylamide is 100:(5-15):(30-50):(20-30):(20-30):(5-10).

4. The flame-retardant quick-setting waterproof inorganic spray grout according to claim 2, characterized in that: The stirring time is 4-10h.

5. The flame retardant quick-setting waterproof inorganic spray grout according to claim 2, characterized in that: The ball milling time is 20-60 min, and the ball milling speed is 100-200 r / min.

6. The flame-retardant quick-setting waterproof inorganic spray grout according to claim 2, characterized in that: The length of the silicon carbide whisker is 10-50 μm, the diameter is 0.1-0.6 μm, and the particle size of the calcium oxide is 50-100 nm.

7. The flame-retardant quick-setting waterproof inorganic spray grout according to claim 1, characterized in that: The cement is ordinary Portland cement PO42.

5.

8. The flame-retardant quick-setting waterproof inorganic spray grout according to claim 1, characterized in that: The coarse aggregate is pebbles and crushed stones, and the particle size thereof is 5-10 mm.

9. The flame-retardant quick-setting waterproof inorganic spray grout according to claim 1, characterized in that: The fine aggregate is natural sand or artificial sand, and its particle size is 0.25-0.5mm.

10. A method for preparing a flame-retardant quick-setting waterproof inorganic spray grout according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, weigh cement, coarse aggregate and fine aggregate in proportion and mix them to form powder; S2, sequentially adding magnesium aluminum hydrotalcite, flame retardant and waterproof functional components, dry powder accelerator and water to the powder, mixing evenly, and stirring at a speed of 100-400 rpm for 15 minutes to obtain a spraying material.

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