Ultra-light and low-strength foam glass, its preparation method and the arresting system composed thereof

Abstract

The present invention discloses a super-lightweight and low-strength foam glass, belonging to the field of inorganic non-metallic materials engineering and applications, and is composed of the following components in weight percentages: hollow glass microspheres: 50-88%; light inert fillers: 7-45%; organic binders: 1-4%; inorganic binders: 3-15%; thickeners: 0.05-1%; coupling agents: 0.03-0.8%. The preparation method of the above-mentioned foam glass and a barrier system composed of the same are also disclosed. The present invention uses the particle packing method to prepare foam glass instead of the traditional high-temperature foaming method, and can adjust the packing height according to the material thickness required by the barrier system, effectively solving the problem of low thickness of the foam glass prepared by the traditional high-temperature foaming method. The use of low-temperature sintering solves the problems of thermal stress defects, anisotropy of traditional characteristic materials, and long-term service of EMAS.

Description

Technical Field

[0001] The present invention relates to the field of inorganic non-metallic material engineering and applications, and in particular to an ultra-lightweight low-strength foam glass, a preparation method thereof, and a barrier system formed thereby. Background Art

[0002] The Engineered Material Arresting System (EMAS) is a proven technology that effectively reduces the risk of aircraft overrunning the runway, having successfully stopped 18 overrun aircraft. Installed outside the runway end, the EMAS utilizes an ultra-lightweight foam concrete material with specific mechanical properties, typically 20 to 70 cm thick. When an aircraft overruns the runway and travels a certain distance, it enters the foam concrete. Under the pressure of the wheels, the foam concrete collapses and absorbs the aircraft's kinetic energy, slowly slowing the aircraft to a stop while ensuring the safety of both the crew and the aircraft structure.

[0003] EMAS has very stringent requirements for the material's collapse energy absorption performance, which is mainly reflected in two aspects: First, the material's penetration compressive strength range is narrow. For example, the lightweight foam concrete disclosed in Chinese patent application ZL201710311732.6 (A silicate-based lightweight foam concrete and its preparation method) preferably has a penetration compressive strength of 0.2 to 0.45 MPa. If the material's penetration compressive strength is low, after the aircraft rushes into the EMAS, it will not be able to be stopped at the set distance due to insufficient energy absorbed by the material's collapse. If the material's penetration compressive strength is high, the aircraft's wheels may not be able to crush the characteristic material, which may also cause the aircraft to run out of the runway end safety zone; or cause the aircraft's landing gear to break, resulting in serious casualties to the people on board. Second, the material's collapse performance does not change significantly during its service life. Once the material's penetration compressive strength exceeds the design strength range, the EMAS's arresting safety cannot be guaranteed.

[0004] EMAS materials are exposed to the exposed environment of airport runway ends throughout their service life. Existing cement-based ultra-lightweight foamed concrete, however, experiences continuous hydration of its binder under the action of water, leading to an increase in material strength that may exceed design limits. Furthermore, existing cement-based ultra-lightweight foamed concrete suffers from durability issues caused by environmental factors such as freeze-thaw, carbonization, and large temperature swings, resulting in a decrease in its crumple energy absorption properties. Therefore, ensuring the stability of material performance is a major technical challenge in ensuring the long-term serviceability of EMAS.

[0005] Foamed glass has excellent properties such as corrosion resistance and good chemical stability, and can maintain stable performance for a long time in outdoor exposure environments. It is called a green and environmentally friendly material. Moreover, like foamed concrete, it has a lightweight and porous structure and has the characteristics of collapse energy absorption. If it can be applied to the special material arrestment system to replace the existing cement-based ultra-lightweight foamed concrete material, it may effectively solve the problems existing in the current EMAS.

[0006] At present, the preparation method of foamed glass is mostly the powder sintering method. The essence of preparing foamed glass by the powder sintering method is to sinter the batch materials together and foam them by heating. First, raw materials such as glass powder, foaming agent, and additive are mixed and ground into powder to obtain the batch materials. Then, the batch materials are heated and sintered and foamed in a kiln to obtain foamed glass. The sintering and foaming temperature is generally 700-1000°C. At present, the foamed glass prepared by the powder sintering method generally has defects such as too large difference in internal pore diameters, uneven bubble distribution, uneven surface, and even non-foaming of some mixture materials. Moreover, the thickness of the obtained foamed glass is low (generally less than 20 cm), and the overall mechanical properties are relatively high (the compressive strength is generally higher than 0.7 Mpa). Therefore, the existing foamed glass cannot be used in the EMAS system, and solving the problems of poor homogeneity, low thickness, and high compressive strength of the existing foamed glass is the primary task in the field of applying it to the special material arrestment system. Summary of the Invention

[0007] One of the purposes of the present invention is to provide a super-lightweight and low-strength foamed glass to solve the above problems.

[0008] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0009] A super-lightweight and low-strength foamed glass is composed of the following components in weight percentage:

[0010] Hollow glass microspheres: 50-88%; Lightweight inert filler: 7-45%; Organic binder: 1-4%; Inorganic binder: 3-15%; Thickener: 0.05-1%; Coupling agent: 0.03-0.8%;

[0011] The sum of the weight percentages of the above components is 100%.

[0012] Among them, the hollow glass microspheres serve as the main material of the foam glass structure; the light inert filler is used to improve the fluidity of the powder, making it easy to mix evenly and reducing the raw material cost; the organic binder is used to bond the hollow glass microspheres and the light inert filler; part of the inorganic binder is used to bond the hollow glass microspheres and the light inert filler, and the other part is used to bond the spherical green body; the thickening agent is used to increase the viscosity of the mixture, making it easy to form into a mass and not loose; the coupling agent is used to improve the dispersion state of the hollow glass microspheres and the inert filler, improve the interfacial action between the two substances, and promote the combination of the glass microspheres, filler and organic binder.

[0013] In addition, during preparation, water with a mass ratio of 40-200% of the total weight of the above components is also added.

[0014] The foam glass of the present invention has the advantages of ultra-light weight, low strength, good homogeneity, etc.

[0015] As a preferred technical solution, the bulk density of the hollow glass microspheres is 0.1-0.15 g / cm 3 , and the average particle size is 68 μm. The hollow glass microspheres are a known material, and its main characteristics are that the density is smaller than that of glass microspheres, and it has high compressive strength, high melting point, high resistivity, small thermal conductivity coefficient and thermal shrinkage coefficient. Its main component is borosilicate. The particle size of commercially available hollow glass microspheres is generally 10-250 μm, and the bulk density is generally 0.1-1 g / cm 3 , and the wall thickness is generally 1-2 μm;

[0016] The suitable bulk density of the hollow glass microspheres used in the present invention is 0.1-0.15 g / cm 3 , and the bulk density and particle size of the hollow glass microspheres determine the bulk density and mechanical properties of the finally prepared foam glass: the greater the bulk density of the hollow glass microspheres, the higher the strength, and the smaller the bulk density, the lower the strength; the particle size and wall thickness of the microspheres determine the bulk density. When the wall thickness is constant, the smaller the particle size, the higher the bulk density. The inventors of the present application have proved through a large number of experiments that only when the suitable bulk density of the hollow glass microspheres is 0.1-0.15 g / cm 3 can a porous material with mechanical properties meeting the requirements of the barrier system be prepared, and materials outside this range cannot achieve the present invention.

[0017] As a preferred technical solution, the light inert filler is microsilica powder with a bulk density of 0.15-0.2 g / cm 3 .

[0018] The above-mentioned microsilica powder is microsilica powder directly collected from the dust collection of a smelter, also known as silicon raw ash, and its bulk density is generally 0.13-0.22 g / cm 3, the silicon ash used in the present invention can be purchased from any microsilica powder manufacturer. Those skilled in the art can understand that, in addition to microsilica powder, other materials with similar physical and chemical properties (inert, light weight) that can improve the fluidity of the powder can replace microsilica powder.

[0019] As a preferred technical solution, the organic binder is selected from at least one of polyurethane, epoxy resin, and polyacrylic resin.

[0020] As a preferred technical solution, the inorganic binder components are phosphoric acid and aluminum hydroxide, and the molar ratio of phosphoric acid to aluminum hydroxide is 2.5 - 4:1.

[0021] As a preferred technical solution, the thickener is selected from at least one of methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl methyl cellulose.

[0022] As a preferred technical solution, the coupling agent is selected from one or more of silane coupling agents.

[0023] The second object of the present invention is to provide a method for preparing the above ultra-lightweight and low-strength foam glass, comprising the following steps:

[0024] (1) Preparation of spherical green bodies: Weigh hollow glass microspheres, light inert fillers, organic binders, part of the inorganic binder, thickeners, coupling agents, and part of the water in proportion, pour them into a mixer and stir to obtain a uniformly mixed flexible mass (similar to kneading dough to form "dough"), and then place it in a granulator to obtain spherical green bodies with a diameter of 0.1 - 5 mm;

[0025] (2) Sintering: Fill the spherical green bodies prepared in step (1) into a mold, and heat them in a high-temperature furnace at a heating rate of 5 - 8 °C / min to 300 - 400 °C for atmospheric sintering, hold for 30 - 60 min, and then cool with the furnace to obtain ultra-lightweight and low-strength foam glass.

[0026] The inventor found through a large number of experiments that when the temperature is 150 - 250 °C, the main component of the inorganic binder is Al(H2PO4)3; when the temperature rises to 250 °C, the main component of the inorganic binder is Al(HP2O7)·2.5H2O; when the temperature rises to 350 °C, the inorganic binder phase is all monoclinic cyclic metaphosphate aluminum Al2P6O 18 (B-type Al(PO3)3). In a low-temperature environment, the aluminum phosphate system is weakly acidic, easy to absorb moisture, and its structure is unstable and prone to decomposition. In a high-temperature environment, metaphosphate aluminum is an inorganic macromolecular cyclic structure connected by P-O-P covalent bonds. At this time, the hydroxyl groups in the binder have completely disappeared, and it has good high-temperature stability. Therefore, the sintering temperature of the present invention is set at 300 - 400 °C.

[0027] As a preferred technical solution,

[0028] In the preparation of the spherical green body in step (1), the following steps are further included:

[0029] (a1) Preparation of inorganic adhesive solution: Weigh aluminum hydroxide and phosphoric acid solution according to the formula. Under the stirring rate of 300 - 700 r / min and the condition of constant temperature water bath at 60 - 90 °C, add aluminum hydroxide to the phosphoric acid solution in batches and stir to dissolve until the solution is clear after the reaction is complete, obtaining an inorganic adhesive solution;

[0030] It should be noted that: In step (1), all the weighed materials are mixed and stirred. Before the mixing and stirring, a part of the inorganic binder and a part of water weighed need to be prepared into an inorganic binder solution first;

[0031] (b1) Drying: Place the flexible mass obtained in step (1) in an oven at 50 - 80 °C for constant temperature for 0.5 - 2 h or in a cool and dry indoor environment for 6 - 24 h;

[0032] In the sintering in step (2), the following steps are further included:

[0033] (2a) Screening: Screen spherical green bodies with a diameter of 2 - 5 mm and a bulk density less than 160 kg / m 3 ;

[0034] (2b) Atomization: Heat the remaining inorganic adhesive solution in step (1) to 60 - 90 °C and perform atomization treatment;

[0035] (2c) Wetting: During the process of filling the spherical green body into the mold, spray the atomized inorganic adhesive solution onto the surface of the spherical green body in batches; and, the spherical green bodies are filled in layers according to the particle strength, so that the particle strength of the lower layer ≥ the middle layer ≥ the upper layer, or use different formulas to produce particles with different strengths but the same particle size. For example, reducing the content of hollow glass microspheres and increasing the content of inorganic binder in the formula can make the material have higher strength; the filling thickness of the green body is 0.1 - 0.8 m;

[0036] The purpose of filling in layers is that the foamed glass after sintering has a gradient strength and can provide a blocking force for airplanes with different weights and tire pressures. For blocking large airplanes, when designing the EMAS, materials with high compressive strength characteristics are generally selected to provide a large blocking force. At this time, if a small airplane rushes into the blocking bed, due to its low tire pressure, it may not be able to crush the characteristic material and thus there is no blocking effect, or it may be able to crush a certain depth of the characteristic material, and it may also cause damage to the landing gear structure of the small airplane due to the high blocking force and pose a risk. If the strength of the upper layer of the foam material is low and the strength of the lower layer is high, then it has a blocking force for different types of airplanes.

[0037] (2d) After filling the spherical green body into the mold, apply a pressure of 0.01 to 0.15 Mpa to the green body for 5 to 30 s. The purpose is to make it more conducive to the fitting of adjacent spherical green bodies and form an integral body after sintering.

[0038] As a preferred technical solution, the density of the ultra-light and low-strength foam glass prepared by the method is 90 to 140 kg / m 3 , the "double-hole stress-crush degree curve" is in a three-stage form, the average double-hole penetration compressive strength is 0.2 to 0.5 Mpa, the semi-collapse energy softening coefficient is 80% to 120%, and the frost resistance coefficient is 0.8 to 1.2. Among them, the average double-hole penetration compressive strength is: the average value of the penetration compressive strength at each point when the crush degree is 0.2 to 0.6.

[0039] The test method of the "double-hole stress-crush degree curve" includes the following steps:

[0040] Step 1, cut the foam glass into regular blocks, the length, width, and height of the blocks are not less than 20 cm, check the appearance of the block samples, and there should be no obvious cracks, missing corners, or other defects;

[0041] Step 2, measure the height of the sample with a steel straightedge, and the result is accurate to 0.5 mm;

[0042] Step 3, connect the compression rod to the universal material testing machine, and measure the diameter of the end of the compression rod with a vernier caliper, accurate to 0.01 mm;

[0043] Step 4, place the sample horizontally under the compression rod, make the axis of the compression rod perpendicular to the sample, and its projection on the sample is not less than 5 cm from the periphery of the sample;

[0044] Step 5, start the universal material testing machine, continuously apply a load at a compression speed of 500 mm / min until the crush degree (crush degree = compression depth / sample height) reaches more than 0.8;

[0045] Step 6, retract the compression rod until it is higher than the upper surface of the sample, horizontally move the position of the sample until the projection of the end of the compression rod in the vertical direction is tangent to the cylindrical cavity formed in the sample in Step 5 and is not less than 5 cm from the periphery of the sample;

[0046] Step 7, start the universal material testing machine again, continuously apply a load at a compression speed of 500 mm / min, and record the stress and crush degree during the compression process until the crush degree reaches more than 0.8.

[0047] The sequence of the more preferable preparation method of the present invention is as follows: weighing raw materials → preparing inorganic adhesive solution → stirring to obtain a flexible mass → drying → granulating → screening → filling into a mold → atomizing and wetting → pressurizing → sintering under normal pressure → cooling; among them, drying, screening, and atomizing and wetting are not essential steps for preparing this material, but they are more preferable steps.

[0048] Among them, the purpose of preferably drying in the present invention is to reduce the viscosity of the flexible mass to facilitate cutting into spheres in a granulator. In order to better and faster mix the raw materials evenly, an excessive amount of water needs to be added. However, if too much water is added, drying is required; if the raw material ratio is appropriate and the moisture content of the mixture is low, granulation can be carried out directly.

[0049] The purpose of preferably screening in the present invention is to select materials with uniform particle size and consistent bulk density. One is to facilitate layering and filling according to particle size and bulk density, and the other is to solve the problem of homogeneity within the same layer.

[0050] The purpose of preferably atomizing and wetting in the present invention is that the spraying is more uniform after atomization. The wetting with inorganic binder solution can increase the bonding force between spherical green bodies, better avoid overall looseness after sintering, and prevent the material from being damaged due to insufficient bonding force during handling.

[0051] The preparation method of the present invention is simple to operate and has a low sintering temperature, and can prepare ultra-light and low-strength foam glass with different thicknesses and gradient strengths at low cost.

[0052] The third object of the present invention is to provide a barrier system composed of the above-mentioned ultra-light and low-strength foam glass. The technical solution adopted is that the barrier system sequentially includes a paving surface layer, a waterproof bonding layer, an ultra-light and low-strength foam glass layer, a bonding agent layer, and a protective layer from bottom to top.

[0053] As a preferred technical solution, except for the paving surface layer, the total thickness of the system is 15 - 70 cm, wherein the thickness of the waterproof bonding layer is 0.1 - 1 cm, the thickness of the ultra-light and low-strength foam glass layer is 10 - 70 cm, the thickness of the bonding agent layer is 0.1 - 1 cm, and the thickness of the waterproof layer is 0.1 - 0.5 cm.

[0054] As a preferred technical solution, the waterproof bonding layer is one or more of asphalt and silicone sealant, and the dosage is 0.4 - 3 kg / m 2 .

[0055] As a preferred technical solution, the bonding agent layer is one or more of silicone, epoxy resin, and polyurethane, and the dosage is 0.2 - 1 kg / m 2 .

[0056] As a preferred technical solution, the protective layer is a polyester polymer material.

[0057] The arresting system of the present invention has a simple structure, a convenient installation method, and good weather resistance.

[0058] The installation method of the above-mentioned arresting system is characterized by including the following steps:

[0059] (1) Clean and dry the paving surface layer;

[0060] (2) Lay a waterproof bonding layer on the paving surface layer after the cleaning and drying treatment in the above step, with a dosage of 1 - 4 kg / m 2 ;

[0061] (3) Lay a super-lightweight and low-strength foam glass layer on the waterproof bonding layer;

[0062] (4) Roll-coat an adhesive layer on the super-lightweight and low-strength foam glass layer, with a dosage of 0.2 - 1 kg / m 2 ;

[0063] (5) Install a protective layer on the adhesive layer to obtain the product.

[0064] Compared with the prior art, the advantages of the present invention are as follows:

[0065] (1) The present invention uses the particle packing method to prepare foam glass instead of the traditional high-temperature foaming method, and the packing height can be adjusted according to the required material thickness of the arresting system, effectively solving the problem of low thickness of foam glass prepared by the traditional high-temperature foaming method;

[0066] (2) The sintering temperature of the present invention is greatly reduced, with less energy consumption, and super-lightweight and low-strength foam glass can be obtained at low cost;

[0067] (3) Due to the low sintering temperature of the present invention, the hollow glass microspheres and inert fillers constituting the pore structure do not undergo physical and chemical reactions such as melting and foaming. Therefore, the prepared foam glass has good homogeneity, solving the problems of thermal stress defects and anisotropy caused by high-temperature foaming / chemical foaming of traditional special materials (foamed glass, silicate-based special materials);

[0068] (4) The super-lightweight and low-strength foam glass with gradient strength prepared by the particle packing method of the present invention can play an arresting effect on aircraft with different operating weights;

[0069] (5) The present invention can adjust the porosity of the material by adjusting the particle size according to the design requirements of the arresting system, and prepare foam glass with ultra-low density and ultra-low strength;

[0070] (6) The super-lightweight and low-strength foam glass prepared by the present invention is an inert special material, and its structure and performance are better than those of traditional silicate-based special materials, effectively solving the problem of long-term service of EMAS. Description of the Drawings

[0071] Figure 1 It is the structural diagram of the arresting system in Embodiment 1 of the present invention;

[0072] In the figure, 1, paving surface layer; 2, waterproof bonding layer; 3, ultra-lightweight and low-strength foam glass layer; 4, adhesive layer; 5, protective layer. Specific embodiments

[0073] The present invention will be further described below with reference to the accompanying drawings.

[0074] Embodiment 1

[0075] A kind of ultra-lightweight and low-strength foam glass, the weight percentages of each raw material are: hollow glass microspheres 58%, microsilica powder 31%, epoxy resin 3.3%, phosphoric acid 5.4%, aluminum hydroxide 1.6%, carboxymethyl cellulose 0.2%, trichlorovinylsilane 0.5%. In addition to the above components, when preparing, it also includes water with a mass ratio of 80% to the total weight of each component.

[0076] In this embodiment, the hollow glass microspheres are purchased from Shanxi Hainuo Technology Co., Ltd., model HN25, with a bulk density of 0.12 g / cm 3 , and the particle size is 68 μm; the microsilica powder uses silicon ash, with a bulk density of 0.16 g / cm 3 , and the average particle size is 0.3 μm.

[0077] The preparation method of the above ultra-lightweight and low-strength foam glass includes the following steps:

[0078] (1) Prepare a 50wt% phosphoric acid solution. Under the stirring rate of 500 r / min and the condition of a constant water bath at 90 °C, add aluminum hydroxide to the phosphoric acid solution in batches and stir to dissolve until the solution is clear after the reaction is complete, and then add the remaining water to obtain an inorganic adhesive solution;

[0079] (2) Pour the hollow glass microspheres and microsilica powder into a blender for premixing, then pour the epoxy resin, trichlorovinylsilane and part of the inorganic adhesive solution prepared in step (1) (taking 95% of the volume ratio of the inorganic adhesive solution) into the blender and stir, and then pour the carboxymethyl cellulose into the blender and mix evenly to obtain a flexible mass;

[0080] (3) Place the flexible mass obtained in step (2) in an oven at 80 °C for 1 h to remove the excess water in the flexible mass, and then place it in a granulator to obtain spherical green blanks with a diameter of 5 mm;

[0081] (4) Fill the spherical green body obtained in step (3) into a mold, with a filling thickness of 52 cm. During the filling process, atomized remaining inorganic adhesive solution (i.e., the remaining 5 vol% after adding in step (2)) is sprayed onto the surface of the spherical green body in batches; after filling, apply a pressure of 0.05 Mpa to the green body for 10 s; sinter without pressure in a high-temperature furnace by heating to 350 °C at a rate of 5 °C / min, keep the temperature for 45 min, and then cool with the furnace to obtain ultra-lightweight and low-strength foam glass;

[0082] An arresting system composed of the above ultra-lightweight and low-strength foam glass, which is a multi-layer composite structure, such as Figure 1 shown, from bottom to top are paving surface layer 1, waterproof bonding layer 2, ultra-lightweight and low-strength foam glass layer 3, adhesive layer 4 and protective layer 5.

[0083] Among them, the waterproof bonding layer 2 is paved with #34518 asphalt produced by Kleifu; the adhesive layer 4 is silicone sealant 668 produced by Guibao Technology; the protective layer 5 is an unsaturated polyester top cover produced by Dongcai Technology; it should be noted that the paving surface layer 1 is the airport runway pavement, which is divided into cement concrete pavement (with a density generally of 1900 - 2500 kg / m 3 , and a thickness generally of about 30 cm) and asphalt concrete pavement (with a density generally of 2400 kg / m 3 , and a thickness generally of 20 cm). The present invention does not make specific requirements on the thickness, density, strength and other characteristics of the paving surface, as long as it meets the airport pavement construction specifications.

[0084] The above method for installing the arresting system includes the following steps:

[0085] Step 1, clean and dry the paving surface layer 1;

[0086] Step 2, lay the waterproof bonding layer 2 on the paving surface layer 1. The asphalt paving temperature shall not be lower than 140 °C, and the dosage is 2.5 kg / m 2 ; the thickness of the waterproof bonding layer 2 in this embodiment is about 3 mm, and the density is about 1.3 g / cm 3 ;

[0087] Step 3, install the ultra-lightweight and low-strength foam glass layer 3 on the waterproof bonding layer 2; the thickness is 20 - 70 cm, and the density is 90 - 140 kg / m 3 ; the thickness and density need to be calculated according to the aircraft weight and tire pressure;

[0088] Step 4, roll-coat the adhesive layer 4 on the ultra-lightweight and low-strength foam glass layer 3, with a dosage of 0.3 kg / m 2 ; the thickness of the adhesive layer 4 is about 1 mm, and the density is about 1.2 g / cm 3 ;

[0089] Step 5, install a protective layer 5 on the adhesive layer 4. The thickness of the protective layer 5 is about 3 mm, and the density is 2000 kg / m 3 .

[0090] Example 2:

[0091] A super-lightweight and low-strength foam glass, with the weight percentages of each raw material as follows: hollow glass microspheres 75%, microsilica powder 9%, epoxy resin 3.35%, phosphoric acid 9.5%, aluminum hydroxide 2.5%, hydroxymethyl cellulose 0.25%, trichlorovinylsilane 0.4%. In addition to the above components, when preparing, water with a mass ratio of 68% of the total weight of each component is also included.

[0092] The preparation method of the above super-lightweight and low-strength foam glass includes the following steps:

[0093] (1) Prepare a phosphoric acid solution with a mass concentration of 50%. Under the stirring rate of 400 r / min and the condition of a constant water bath at 80 °C, add aluminum hydroxide to the phosphoric acid solution in batches and stir to dissolve until the solution is clear after the reaction is complete, then add the remaining water to obtain an inorganic adhesive solution;

[0094] (2) Pour hollow glass microspheres, microsilica powder, epoxy resin, hydroxymethyl cellulose, and trichlorovinylsilane into a blender and stir to obtain a uniformly mixed flexible mass;

[0095] (3) Place the flexible mass obtained in step (2) in a cool and dry indoor environment for 18 h to remove excess moisture in the flexible mass, and then place it in a granulator to obtain spherical green blanks with a diameter of 1 - 5 mm;

[0096] (4) Screen the spherical green blanks obtained in step (3), and select spherical green blanks with diameters of 2 mm, 4 mm, and 5 mm and a bulk density < 160 kg / m 3 ;

[0097] (5) Layer the spherical green blanks obtained in step (4) into a mold, with 2 mm, 4 mm, and 5 mm spherical green blanks from bottom to top. The filling thickness is 63 cm, and the thickness of each layer is 21 cm. Apply a pressure of 0.08 Mpa to the green blanks for 20 s; sinter without pressure in a high-temperature furnace by heating to 380 °C at a rate of 4 °C / min, keep the temperature for 60 min, and then cool with the furnace to obtain the super-lightweight and low-strength foam glass.

[0098] A barrier system composed of the above super-lightweight and low-strength foam glass. This system is a multi-layer composite structure, which is successively a paving surface layer 1, a waterproof adhesive layer 2, a super-lightweight and low-strength foam glass layer 3, an adhesive layer 4, and a protective layer 5 from bottom to top.

[0099] Among them, the waterproof bonding layer 2 is paved with zero-degree asphalt produced by Zhongtian Road Industry; the adhesive layer 4 is a two-component silicone sealant produced by Tuoli Technology; the protective layer 5 is an unsaturated polyester top cover produced by Dongcai Technology.

[0100] The above-mentioned installation method of the barrier system includes the following steps:

[0101] Step 1, clean and dry the paving surface layer 1;

[0102] Step 2, lay the waterproof bonding layer 2 on the paving surface layer 1. The asphalt paving temperature shall not be lower than 130°C, and the dosage is 2 kg / m 2 ;

[0103] Step 3, install the ultra-light and low-strength foam glass layer 3 on the waterproof bonding layer 2;

[0104] Step 4, roll-coat the adhesive layer 4 on the ultra-light and low-strength foam glass layer 3, and the dosage is 0.2 kg / m 2 ;

[0105] Step 5, install the protective layer 5 on the adhesive layer 4.

[0106] Example 3:

[0107] Based on Example 1, only the following content is different: the weight percentages of each raw material are: hollow glass microspheres 88%, microsilica powder 7%, epoxy resin 1.25%, phosphoric acid 2.37%, aluminum hydroxide 0.63%, carboxymethyl cellulose 0.15%, trichlorovinyl silane 0.6%. In addition to the above components, water with a mass ratio of 40% of the total weight of each component is also included during preparation; no drying is performed; the sintering temperature is 300°C; the rest remains unchanged.

[0108] Example 4:

[0109] Based on Example 1, compared with Example 1, only the weight percentages of hollow glass microspheres and microsilica powder are different, which are 88% and 7% respectively.

[0110] Example 5

[0111] Based on Example 2, there is only no atomization and wetting step. The rest remains unchanged.

[0112] The results show that without the atomization and wetting step, only relying on pressure to make the green bodies fit together results in weak bonding force between the green bodies, and the crushing strength of the material after sintering decreases, and the semi-collapse energy softening coefficient and freeze resistance coefficient decrease significantly.

[0113] Comparative Example 1

[0114] This comparative example is based on Example 2, with only the sintering temperature changed to 290 °C and the rest remaining unchanged. The results show that when the sintering temperature is too low, the inorganic binder phase cannot all be monoclinic cyclic metaphosphate aluminum Al2P6O 18 (type B Al(PO3)3), resulting in a slight decrease in the crushing strength of the material, but a significant decrease in the softening coefficient of the semi-crushing energy and the anti-freezing coefficient.

[0115] Comparative Example 2

[0116] This comparative example is based on Example 2, with only the raw material composition different. The weight percentages of each raw material are as follows: hollow glass microspheres 90%, microsilica 4.5%, epoxy resin 2.35%, phosphoric acid 2.0%, aluminum hydroxide 0.5%, carboxymethyl cellulose 0.25%, trichlorovinylsilane 0.4%. The rest remains unchanged.

[0117] The results show that when the proportion of hollow glass microspheres is too high and the proportion of inorganic binder is too low, that is, the content of inorganic binder per unit volume is small, it cannot bond the microspheres together well, resulting in low strength of the green body pore wall, and thus a significant reduction in the crushing strength.

[0118] Comparative Example 3

[0119] This comparative example is based on Example 2, with only the raw material composition different. The weight percentages of each raw material are as follows: hollow glass microspheres 70%, microsilica 10%, epoxy resin 3.35%, phosphoric acid 12.2%, aluminum hydroxide 3.8%, carboxymethyl cellulose 0.25%, trichlorovinylsilane 0.4%. The rest remains unchanged.

[0120] The results show that when the proportion of hollow glass microspheres is low and the proportion of inorganic binder is high, that is, the content of inorganic binder per unit volume is large, the density of the sintered material is large and the pore wall strength is high, resulting in a significant increase in the crushing strength.

[0121] Comparative Example 4

[0122] Silicate-based special material

[0123] The silicate-based special material in this comparative example refers to the LANZU-1 type silicate-based special material produced by Aviation Science and Technology Development Co., Ltd. (Beijing) using P·II 52.5R cement produced by Dalian Onoda Cement Co., Ltd. as the main raw material.

[0124] Comparative Example 5

[0125] Conventional foamed glass

[0126] The conventional foamed glass of this comparative example is from Sinosteel Maanshan Institute of Mining Research New Materials Technology Co., Ltd. The main components (by mass percentage) are: waste glass 68.5%, albite 15.1%, hollow glass microspheres 11.76%, sodium nitrate 0.18%, calcium carbonate 0.06%, borax 0.66%, boric acid 3.45%, and fluorite 0.29%.

[0127] The ultra-lightweight and low-strength foamed glass prepared in Examples 1 to 5 and the process and performance indicators of Comparative Examples 1-5 are compared in Table 1 below.

[0128] Table 1

[0129]

[0130] In Table 1, the unit of the sintering temperature is °C. The test method for the density (unit: kg / m 3 ) is the volume method, the thickness (unit: cm) is measured with a steel ruler, and the test of the crushing strength (unit: MPa), the softening coefficient of the semi-collapse energy (industry standard: 80-120, unit: %), the mass loss rate (industry standard: 0-5, unit: %), and the frost resistance coefficient (industry standard 0.8-1.2) refers to or references MH / T 5111-2015.

[0131] It can be seen from the performance data in Table 1 and the requirements of the industry standard "Specialty Material Arresting System" (MH / T5111-2015): The ultra-lightweight and low-strength foamed glass of the present invention can meet the performance requirements for use in the specialty material arresting system at the runway end of the airport; and compared with the traditional foamed glass, the sintering temperature and density are significantly reduced, and the thickness is significantly increased; compared with the silicate-based specialty materials, the crushing strength is comparable, but the durability indicators such as the softening coefficient of the semi-collapse energy, the mass loss rate, and the frost resistance coefficient are significantly better.

[0132] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A preparation method of ultra-light and low-strength foam glass, characterized in that the ultra-light and low-strength foam glass is composed of the following components in weight percentage: Hollow glass microspheres: 50 - 88%; Light inert fillers: 7 - 45%; Organic binder: 1 - 4%; Inorganic binder: 3 - 15%; Thickener: 0.05 - 1%; Coupling agent: 0.03 - 0.8%; The sum of the weight percentages of the above components is 100%; The preparation method includes the following steps: (1) Preparation of spherical green bodies: Weigh hollow glass microspheres, light inert fillers, organic binder, part of the inorganic binder, thickener, coupling agent, and part of the water in proportion, pour them into a blender and stir to obtain a uniformly mixed flexible mass, and then place it in a granulator to obtain spherical green bodies with a diameter of 0.1 - 5 mm; (2) Sintering: Fill the spherical green bodies prepared in step (1) into a mold, and heat them in a high-temperature furnace at a rate of 5 - 8 °C / min to 300 - 400 °C for atmospheric sintering, keep the temperature for 30 - 60 min, and then cool with the furnace to obtain ultra-light and low-strength foam glass.

2. The method according to claim 1, characterized in that in the preparation of the spherical green bodies in step (1), the following steps are also included: (a1) Preparation of inorganic adhesive solution: Weigh aluminum hydroxide and phosphoric acid solution according to the formula, and add aluminum hydroxide to the phosphoric acid solution in batches under the stirring rate of 300 - 700 r / min and the condition of constant temperature water bath at 60 - 90 °C, stir and dissolve until the solution is clear after the reaction is complete to obtain an inorganic adhesive solution; (b1) Drying: Place the flexible mass obtained in step (1) in an oven at 50 - 80 °C for constant temperature for 0.5 - 2 h or in a cool and dry indoor environment for 6 - 24 h; in the sintering in step (2), the following steps are also included: (2a) Screening: Screening spherical green compacts with a diameter of 2 to 5 mm and a bulk density of less than 160 kg / m 3 ; (2b) Atomization: Heat the remaining inorganic adhesive solution in step (1) to 60 - 90 °C and perform atomization treatment; (2c) Wetting: During the process of filling the spherical green bodies into the mold, spray the atomized inorganic adhesive solution onto the surface of the spherical green bodies in batches; and the spherical green bodies are filled in layers according to the particle strength, so that the particle strength of the lower layer ≥ the middle layer ≥ the upper layer, and the filling thickness of the green bodies is 0.1 - 0.8 m; (2d) After filling the spherical green bodies into the mold, apply a pressure of 0.01 - 0.15 Mpa to the green bodies for 5 - 30 s.

3. The method according to claim 1 or 2, characterized in that, The density of the ultra-light and low-strength foam glass prepared by the method is 90-140 kg / m 3 , the double-hole stress-crush degree curve is in a three-stage form, the average double-hole penetration compressive strength is 0.2-0.5 Mpa, the semi-crushing energy softening coefficient is 80%-120%, and the frost resistance coefficient is 0.8-1.

2.

4. The method according to claim 1, wherein The bulk density of the hollow glass microspheres is 0.1 to 0.15 g / cm 3 , and the particle size is 40 to 100 μm.

5. The method according to claim 1, wherein The light inert filler is microsilica powder with a bulk density of 0.15 - 0.2 g / cm 3 .

6. The method according to claim 1, characterized in that the organic binder is selected from at least one of polyurethane, epoxy resin, and polyacrylic resin; the component of the inorganic binder is phosphoric acid and aluminum hydroxide, and the molar ratio of phosphoric acid to aluminum hydroxide is 2.5 - 4:1; the thickener is selected from at least one of methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl methyl cellulose; the coupling agent is selected from one or more of silane coupling agents.

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