A high temperature spalling inhibitor and its use in ultra-high performance concrete

Abstract

This application relates to the field of building materials technology, specifically disclosing a high-temperature cracking inhibitor and its application in ultra-high performance concrete. The high-temperature cracking inhibitor is prepared from raw materials including a pressure-relieving grid material, a pressure-relieving channel material, high-temperature toughening fibers, and a hydration product bond-type modifier. The mass ratio of the pressure-relieving grid material, pressure-relieving channel material, high-temperature toughening fibers, and hydration product bond-type modifier is 300:(6-15):(50-100):(1-5). The pressure-relieving grid material is composed of substances including porous materials and molten salt inorganic phase change materials; the pressure-relieving channel material is a molten fiber. The inhibitor of this application exhibits excellent high-temperature cracking prevention effect. Furthermore, the inhibitor of this application avoids the use of expensive synthetic organic fibers, and its preparation process and application method are very convenient.

Description

Technical Field

[0001] This application relates to the field of building materials technology, and more specifically, to a high-temperature cracking inhibitor and its application in ultra-high performance concrete. Background Technology

[0002] Ultra-high performance concrete (UHPC), as a special fiber-reinforced cementitious composite material, possesses superior mechanical and durability properties compared to traditional concrete, making it widely used in high-rise / super high-rise buildings, long-span tunnels, and other structures. However, fire, as one of the most frequent disasters, poses a significant challenge to building structural safety. In the face of fire, due to its dense structure and low permeability, UHPC is more susceptible to high-temperature cracking than ordinary concrete, ultimately leading to concrete spalling, exposed reinforcing steel, and impacting the overall service life and safety of the structure. This undoubtedly limits the application scope of UHPC.

[0003] Chinese patent CN114605117A discloses a high-alkalinity, high-temperature resistant, ultra-high-performance concrete material that does not crack after reaching 600℃. The principle behind this is the incorporation of 0.4–0.7% organic fiber by volume into the concrete mix. The fiber's low melting point helps release the vapor pressure accumulated within the concrete, ultimately reducing or eliminating the risk of high-temperature cracking in UHPC. However, incorporating such a large quantity of organic fiber (typically less than 0.05%) can act as an lap aggregate within the concrete, severely impacting its workability. Patent CN115504741 uses a three-batch addition of polypropylene fiber to prepare a high-temperature resistant hybrid fiber-reinforced concrete, aiming for uniform dispersion within the concrete, but the fiber content still reaches 1.8–2.0 kg / m³. 3 This is unsuitable for applications where self-leveling concrete is required. Furthermore, the large-scale incorporation of organic fibers will continuously induce air in the UHPC slurry during mixing, introducing more harmful pores into the already poorly vented UHPC, ultimately impairing its mechanical properties. In addition, synthetic organic fibers are expensive, and incorporating such a large quantity merely for high-temperature melting does not align with the material's original design intent, and the gases produced during combustion and melting will pollute the environment.

[0004] Chinese patents CN105693166A and CN111099865A avoid incorporating organic fibers and instead employ a special dry-heat combined curing method to improve the high-temperature explosion-proof performance of UHPC. This involves first curing in hot water at 60–90°C for 2–4 days, followed by curing in a dry-heat environment at 100–300°C for 1–3 days. This method aims to completely eliminate free water inside the UHPC through specific curing methods, which has some merit. However, it undoubtedly greatly increases the complexity and difficulty of construction. Furthermore, this curing method is only effective for precast components and is not applicable to cast-in-place concrete sections. It also consumes a large amount of energy and is not environmentally friendly. Chinese patent CN112759291 utilizes shape memory alloys to generate shape memory under high-temperature conditions. The shape memory effect allows it to generate pre-compressive stress on the UHPC matrix in a fire environment, thus enabling the preparation of a UHPC resistant to high-temperature bursting by incorporating shape memory alloy fibers. This method is one of the few that can suppress high-temperature bursting of UHPC without incorporating organic fibers, and it has certain theoretical innovations. However, it has the following problems: 1. Although shape memory alloys can generate restoring stress to recover inelastic strain in high-temperature environments, the weak points in the interface transition zone between the shape memory alloy and the UHPC matrix (especially in high-temperature environments) make it questionable whether the tensile stress generated instantaneously during high-temperature bursting of UHPC is comparable to the compressive stress exerted by the shape memory alloy on the UHPC matrix; 2. Shape memory alloys are expensive, further increasing the cost of UHPC; 3. It only has theoretical feasibility and currently has no practical engineering applications.

[0005] Therefore, it is of great significance to broaden the application range of high-temperature explosion-proof ultra-high performance concrete by minimizing fiber content and avoiding the use of expensive synthetic organic fibers. Summary of the Invention

[0006] To address the issue that existing ultra-high performance concrete either requires the incorporation of large amounts of slender organic fibers or necessitates complex dry-heat curing regimes to eliminate the risk of high-temperature cracking, this study aims to provide a high-temperature cracking inhibitor and its application in ultra-high performance concrete.

[0007] Firstly, this application provides a high-temperature bursting inhibitor, which adopts the following technical solution:

[0008] A high-temperature burst inhibitor is prepared from raw materials including a pressure-relieving grid material, a pressure-relieving channel material, a high-temperature toughening fiber, and a hydration product bond-type modifier. The mass ratio of the pressure-relieving grid material, the pressure-relieving channel material, the high-temperature toughening fiber, and the hydration product bond-type modifier is 300:(6-15):(50-100):(1-5). The pressure-relieving grid material is composed of substances including porous materials and molten salt inorganic phase change materials. The pressure-relieving channel material is a molten fiber.

[0009] By adopting the above technical solution, under high-temperature conditions, the porous material and molten salt inorganic phase change material in the pressure-relieving grid material will form several "grid points," while the pressure-relieving channel material will form "channels" due to melting. The combination of the two can form a "pressure-relieving network" in the system, that is, by combining "zero-dimensional porous materials" with a small amount of "one-dimensional fiber materials" to form a "three-dimensional pressure-relieving network," the inhibitor of this application has a good high-temperature anti-burst effect. At the same time, the inhibitor of this application avoids the use of expensive synthetic organic fibers, and the preparation process and usage method are very convenient.

[0010] Furthermore, the porous material includes nanoporous material and porous silicate material; the mass ratio of the nanoporous material, porous silicate material and molten salt inorganic phase change material is 3:(0.5~1):(0.5~1).

[0011] Furthermore, the porous material comprises one or more combinations of rice husk ash, zeolite powder, and porous quartz powder. The rice husk ash is obtained by calcining and grinding rice husks at 500–750℃, with a particle size of 100–800 nm. The zeolite powder comprises one or more combinations of anticline zeolite, chalcogenide, calcium zeolite, flaky zeolite, sodium zeolite, mordenite, and zeolite, with a particle size of less than 3 μm.

[0012] Furthermore, the molten salt inorganic phase change material includes one or more combinations of industrial waste glass and hollow glass microspheres, with a fineness of 10–100 μm.

[0013] Further, the porous silicate material comprises one or more combinations of aluminosilicate minerals and silicate product waste, with a fineness of 0.6–1.18 mm. Even further, the porous silicate material can be artificial aluminosilicate minerals and / or artificial silicate product waste. The aluminosilicate minerals include one or more combinations of expanded perlite, shale ceramsite, sludge ceramsite, clay ceramsite, and fly ash ceramsite. The silicate product waste includes one or more combinations of waste aerated concrete, waste foamed cement board, waste foamed concrete, and waste ceramsite foamed concrete board.

[0014] Furthermore, the hydration product bond-type modifier includes one or more combinations of metakaolin and finely ground coal gangue powder, with an alumina content of not less than 42% and a fineness of less than 3 μm.

[0015] By adopting the above technical solutions, the hydration product bond type modifier can, firstly, react with calcium hydroxide in cement to generate CASH gel, which has increased chain length and improved strength compared to ordinary cement hydration products, and consumes calcium hydroxide that decomposes at 400℃, thus improving the high-temperature stability of UHPC; secondly, it can promote the formation of calcium aluminum feldspar mineral phase, which is an aluminosilicate phase product mainly composed of ionic and covalent bonds. Compared with conventional cement hydration products mainly composed of van der Waals bonds and hydrogen bonds, it has better high-temperature stability and can synergistically enhance the high-temperature performance of UHPC with high-temperature toughening fibers.

[0016] Further, the pressure relief channel material includes one or more combinations of waste mask fibers, polypropylene fibers, polyvinyl alcohol fibers, and polyethylene fibers, with a length of 5-20 mm and a diameter of 0.01-1 mm. Further, the waste mask fibers can be obtained by shredding waste masks after disinfection, removal of nose pads and ear loops, and include one or more mixtures of non-woven disposable medical masks, activated carbon masks, and N95 masks.

[0017] Furthermore, the high-temperature toughening fiber is composed of whisker-like materials and nanofibers in a mass ratio of 1:(1-2). The whisker-like materials include one or more combinations of calcium silicate whiskers, calcium carbonate whiskers, wollastonite whiskers, mullite whiskers, and gypsum whiskers, and their aspect ratio is not less than 10. The nanofibers include one or more combinations of α-alumina nanofibers, zirconium oxide nanofibers, and graphene oxide nanofibers, and their aspect ratio is not less than 1000.

[0018] Secondly, this application provides an application of a high-temperature cracking inhibitor in ultra-high performance concrete, employing the following technical solution:

[0019] Application of a high-temperature cracking inhibitor in ultra-high performance concrete. The concrete raw materials include the following components by weight: 100 parts cementitious materials; 80-120 parts aggregate; 25-40 parts high-temperature cracking inhibitor; 15-20 parts steel fiber; 1-3 parts water-reducing agent; and 15-25 parts water.

[0020] In summary, this application has the following beneficial effects:

[0021] (1) The high-temperature burst inhibitor used in this application cleverly combines "zero-dimensional porous materials" with a small amount of "one-dimensional fiber materials" to form a "three-dimensional pressure-relieving network" by introducing pressure-relieving grid materials and pressure-relieving channel materials. This overcomes the technical difficulty of traditional methods that require the addition of a large amount of "one-dimensional fiber materials" to form a "three-dimensional pressure-relieving network". Its pressure-relieving principle is as follows: Figure 1 As shown. Specifically, compared to the problem that simply adding a large amount of fiber can affect the workability of concrete, this application introduces materials such as rice husk ash with nanopores, zeolite powder or porous quartz powder, waste glass powder or hollow glass microspheres with micropores (melted at high temperature to form pores), and micro / millimeter-pore artificial aluminosilicate minerals and artificial silicate product waste, etc., so that they form a uniformly distributed multi-scale "pressure relief grid" inside the UHPC. At this time, only a very small amount of fiber is needed to form a vapor pressure relief network. In addition, this invention can also avoid the use of expensive synthetic organic fibers, and achieve high-temperature explosion protection simply by recycling waste mask fibers. In fact, the diameter of waste mask fibers is too large to form an overall "pressure relief network" on their own, but their coupling with the pressure relief grid material can achieve high-temperature explosion protection without affecting the workability and mechanical properties of UHPC.

[0022] (2) The high-temperature bursting inhibitor of this application can effectively disperse the internal steam pressure when ultra-high performance concrete is exposed to fire, so it does not need to be dry heat curing to eliminate internal moisture. That is, it has low humidity sensitivity, saves a lot of energy compared with complex dry heat curing, and can be extended to cast-in-place ultra-high performance concrete components.

[0023] (3) The high-temperature bursting inhibitor of this application can effectively utilize solid wastes from industry, agriculture and construction such as rice husk ash, waste glass and waste aerated concrete, which is of great significance for reducing material costs, saving energy in society and protecting the environment. Attached Figure Description

[0024] Figure 1 This is a schematic diagram illustrating the principle of how a "pressure relief network" composed of multi-scale pressure relief grid materials and pressure relief channel materials suppresses high-temperature bursting of UHPC.

[0025] Figure 2 This is a morphological image after the high-temperature test in Example 1.

[0026] Figure 3 This is a morphological image after the high-temperature test in Example 4.

[0027] Figure 4 This is a morphological image of Comparative Example 1 after the high-temperature test.

[0028] Figure 5 This is a morphological image of Comparative Example 2 after the high-temperature test.

[0029] Figure 6This is a morphological image of Comparative Example 4 after the high-temperature test.

[0030] Figure 7 This is a morphological image of Comparative Example 6 after the high-temperature test.

[0031] Figure 8 This is a morphological image of Comparative Example 7 after the high-temperature test. Detailed Implementation

[0032] The present application will be further described in detail below with reference to the accompanying drawings and embodiments.

[0033] Example

[0034] This application first provides a high-temperature bursting inhibitor, as follows:

[0035] A high-temperature burst inhibitor is prepared from raw materials including a pressure-relieving grid material, a pressure-relieving channel material, a high-temperature toughening fiber, and a hydration product bond-type modifier. The mass ratio of the pressure-relieving grid material, the pressure-relieving channel material, the high-temperature toughening fiber, and the hydration product bond-type modifier is 300:(6-15):(50-100):(1-5). The pressure-relieving grid material is composed of substances including porous materials and molten salt inorganic phase change materials. The pressure-relieving channel material is a molten fiber.

[0036] The porous materials include nanoporous materials and porous silicate materials; the mass ratio of nanoporous materials, porous silicate materials and molten salt inorganic phase change materials is 3:(0.5~1):(0.5~1).

[0037] Furthermore, the porous materials include one or more combinations of rice husk ash, zeolite powder, and porous quartz powder. Rice husk ash is obtained by calcining and grinding rice husks at 500–750℃, with a particle size of 100–800 nm. Zeolite powder is composed of one or more combinations of anticline, chalcogenide, calcium zeolite, flaky zeolite, sodium zeolite, mordenite, and zeolite, with a particle size less than 3 μm. Porous quartz powder has a particle size less than 10 μm.

[0038] Furthermore, the porous silicate material includes one or more combinations of aluminosilicate minerals and silicate product waste, with a fineness of 0.6–1.18 mm. Aluminosilicate minerals include one or more combinations of expanded perlite, shale ceramsite, sludge ceramsite, clay ceramsite, and fly ash ceramsite. Silicate product waste includes one or more combinations of waste aerated concrete, waste foamed cement board, waste foamed concrete, and waste ceramsite foamed concrete board.

[0039] Furthermore, molten salt inorganic phase change materials include one or more combinations of industrial waste glass and hollow glass microspheres, with a fineness of 10–100 μm.

[0040] The hydration product bond modifier includes one or more combinations of metakaolin and finely ground coal gangue powder, with an alumina content of not less than 42% and a fineness of less than 3 μm. In this embodiment, the alumina content of the metakaolin and finely ground coal gangue powder is 45%.

[0041] The pressure-relieving channel material includes one or more combinations of waste mask fibers, polypropylene fibers, polyvinyl alcohol fibers, and polyethylene fibers, with a length of 5–20 mm and a diameter of 0.01–1 mm. Waste mask fibers can be obtained by shredding waste masks after disinfection, removal of nose pads and ear loops, and include one or more mixtures of non-woven disposable medical masks, activated carbon masks, and N95 masks.

[0042] The high-temperature toughening fiber is composed of whisker-like substances and nanofibers in a mass ratio of 1:(1~2).

[0043] Furthermore, the whisker-like materials include one or more combinations of calcium silicate whiskers, calcium carbonate whiskers, wollastonite whiskers, mullite whiskers, and gypsum whiskers, and their aspect ratio is not less than 10. The nanofibers include one or more combinations of α-alumina nanofibers, zirconium oxide nanofibers, and graphene oxide nanofibers, and their aspect ratio is not less than 1000.

[0044] An embodiment of this application also provides an ultra-high performance concrete, the raw materials of which include the following components:

[0045] 100 parts cementitious material; 80-120 parts aggregate; 25-40 parts high-temperature cracking inhibitor; 15-20 parts steel fiber; 1-3 parts water-reducing agent; 15-25 parts water.

[0046] The cementitious material is composed of cement and mineral admixtures in a mass ratio of 1:0.2 to 0.4.

[0047] Furthermore, the mineral admixtures include ultrafine mineral powder and ultrafine fly ash, with a mass ratio of 1:0.5 to 1, and a fineness of less than 3 μm. The cement strength grade is not lower than 42.5; in this embodiment, the cement is Conch PO·42.5.

[0048] The aggregate consists of river sand or manufactured sand with a continuous gradation of 0.075–2.36 mm.

[0049] The steel fibers are straight copper-plated steel fibers with a length of 13mm and a diameter of 0.2mm.

[0050] The water-reducing agent is a polycarboxylate water-reducing agent with a water reduction rate of not less than 40%. In this embodiment, the polycarboxylate water-reducing agent of model Subote 801 is used.

[0051] The preparation method of ultra-high performance concrete includes the following steps:

[0052] (1) Add cementitious materials, high-temperature cracking inhibitors and aggregates and dry mix for 30 seconds;

[0053] (2) Add 3 / 4 water and water-reducing agent and mix for 2 minutes, then add the remaining water and water-reducing agent and continue mixing for 2 minutes;

[0054] (3) Slowly add steel fibers and continue stirring for 3 minutes, then pour into a mold;

[0055] (4) After 24 hours, the formwork is removed and the concrete is cured in a standard or natural manner for 28 days to obtain the ultra-high performance concrete.

[0056] The following is an illustration through specific examples.

[0057] Example 1

[0058] This embodiment provides a high-temperature bursting inhibitor, the raw materials of which include the following components:

[0059] 300 parts of pressure-relieving grid material, 10 parts of pressure-relieving channel material, 65 parts of high-temperature toughening fiber, and 3 parts of hydration product bond-type modifier. The high-temperature burst inhibitor is obtained by uniformly mixing the above raw materials.

[0060] The pressure-relieving grid material is composed of porous quartz powder with a particle size of 5-10μm, waste glass with a fineness of 10-100μm, and waste aerated concrete with a thickness of 0.6-1.18mm in a mass ratio of 3:1:0.5.

[0061] The pressure relief channel is made of waste non-woven disposable medical mask fiber with a length of 12mm and a diameter of 0.1mm.

[0062] The hydration product bond modifier is composed of metakaolin and finely ground coal gangue in a mass ratio of 2:1, and the particle size of the mixture is 1-3 μm.

[0063] The high-temperature toughening fiber is composed of mullite whiskers and α-alumina nanofibers in a mass ratio of 1:1, wherein the aspect ratio of the mullite whiskers is 12 and the aspect ratio of the α-alumina nanofibers is 1100.

[0064] This embodiment also provides an ultra-high performance concrete using the above-mentioned high-temperature bursting inhibitor, the raw materials of which include the following components:

[0065] The product includes 100 parts of cementitious materials, specifically 76 parts of Conch PO·42.5 cement, 12 parts of ultrafine mineral powder, and 12 parts of ultrafine fly ash, wherein the particle size of the ultrafine mineral powder and ultrafine fly ash is 1-3μm; 120 parts of aggregate, specifically 0.075-2.36mm continuously graded river sand; 38 parts of high-temperature cracking inhibitor; 15 parts of straight steel fibers with a diameter of 0.2mm and a length of 13mm; 2 parts of polycarboxylate superplasticizer; and 20 parts of water.

[0066] The preparation method of ultra-high performance concrete in this embodiment includes the following steps:

[0067] (1) Add cementitious materials, high-temperature cracking inhibitors and aggregates and dry mix for 30 seconds;

[0068] (2) Add 3 / 4 water and water-reducing agent and mix for 2 minutes, then add the remaining water and water-reducing agent and continue mixing for 2 minutes;

[0069] (3) Slowly add steel fibers and continue stirring for 3 minutes, then pour into a mold;

[0070] (4) After 24 hours, the formwork is removed and the concrete is cured in a standard or natural manner for 28 days to obtain the ultra-high performance concrete.

[0071] Example 2

[0072] This embodiment provides a high-temperature bursting inhibitor, the raw materials of which include the following components:

[0073] 300 parts of pressure-relieving grid material, 15 parts of pressure-relieving channel material, 100 parts of high-temperature toughening fiber, and 5 parts of hydration product bond-type modifier. The high-temperature burst inhibitor is obtained by uniformly mixing the above raw materials.

[0074] The pressure-relieving grid material is composed of rice husk ash, glass hollow microspheres with a fineness of 10-100μm, and expanded perlite of 0.6-1.18mm in a mass ratio of 3:0.5:1. The rice husk ash is obtained by calcining rice husks at 650℃ and grinding them, with a particle size of 100-800nm.

[0075] The pressure relief channel is made of waste non-woven disposable medical mask fiber with a length of 6mm and a diameter of 0.01mm.

[0076] The hydration product bond modifier is composed of metakaolin and finely ground coal gangue in a mass ratio of 2:1, and the particle size of the mixture is 1-3 μm.

[0077] The high-temperature toughening fiber is composed of calcium silicate whiskers and zirconia nanofibers in a mass ratio of 1:2, wherein the aspect ratio of the calcium silicate whiskers is 15 and the aspect ratio of the zirconia nanofibers is 1200.

[0078] This embodiment also provides an ultra-high performance concrete using the above-mentioned high-temperature bursting inhibitor, the raw materials of which include the following components:

[0079] The product includes 100 parts of cementitious materials, specifically 76 parts of Conch PO·42.5 cement, 12 parts of ultrafine mineral powder, and 12 parts of ultrafine fly ash, wherein the particle size of the ultrafine mineral powder and ultrafine fly ash is 1-3μm; 80 parts of aggregate, specifically 0.075-2.36mm continuously graded river sand; 24 parts of high-temperature cracking inhibitor; 17 parts of straight steel fibers with a diameter of 0.2mm and a length of 13mm; 1 part of polycarboxylate superplasticizer; and 15 parts of water.

[0080] The preparation method of ultra-high performance concrete in this embodiment includes the following steps:

[0081] (1) Add cementitious materials, high-temperature cracking inhibitors and aggregates and dry mix for 30 seconds;

[0082] (2) Add 3 / 4 water and water-reducing agent and mix for 2 minutes, then add the remaining water and water-reducing agent and continue mixing for 2 minutes;

[0083] (3) Slowly add steel fibers and continue stirring for 3 minutes, then pour into a mold;

[0084] (4) After 24 hours, the formwork is removed and the concrete is cured in a standard or natural manner for 28 days to obtain the ultra-high performance concrete.

[0085] Example 3

[0086] This embodiment provides a high-temperature bursting inhibitor, the raw materials of which include the following components:

[0087] 300 parts of pressure-relieving grid material, 6 parts of pressure-relieving channel material, 50 parts of high-temperature toughening fiber, and 1 part of hydration product bond-type modifier. The high-temperature burst inhibitor is obtained by uniformly mixing the above raw materials.

[0088] The pressure-relieving grid material is composed of zeolite powder with a particle size of 1-3μm, waste glass with a fineness of 10-100μm, and waste aerated concrete with a thickness of 0.6-1.18mm in a mass ratio of 3:0.7:0.6.

[0089] The pressure relief channel is made of waste non-woven disposable medical mask fiber with a length of 20mm and a diameter of 1mm.

[0090] The hydration product bond modifier is composed of metakaolin and finely ground coal gangue in a mass ratio of 2:1, and the particle size of the mixture is 1-3 μm.

[0091] The high-temperature toughening fiber is composed of mullite whiskers and α-alumina nanofibers in a mass ratio of 1:1, wherein the aspect ratio of the mullite whiskers is 10 and the aspect ratio of the α-alumina nanofibers is 1000.

[0092] This embodiment also provides an ultra-high performance concrete using the above-mentioned high-temperature bursting inhibitor, the raw materials of which include the following components:

[0093] The product includes 100 parts of cementitious materials, specifically 76 parts of Conch PO·42.5 cement, 12 parts of ultrafine mineral powder, and 12 parts of ultrafine fly ash, wherein the particle size of the ultrafine mineral powder and ultrafine fly ash is 1-3μm; 100 parts of aggregate, specifically 0.075-2.36mm continuously graded river sand; 40 parts of high-temperature cracking inhibitor; 20 parts of straight steel fibers with a diameter of 0.2mm and a length of 13mm; 3 parts of polycarboxylate superplasticizer; and 25 parts of water.

[0094] The preparation method of ultra-high performance concrete in this embodiment includes the following steps:

[0095] (1) Add cementitious materials, high-temperature cracking inhibitors and aggregates and dry mix for 30 seconds;

[0096] (2) Add 3 / 4 water and water-reducing agent and mix for 2 minutes, then add the remaining water and water-reducing agent and continue mixing for 2 minutes;

[0097] (3) Slowly add steel fibers and continue stirring for 3 minutes, then pour into a mold;

[0098] (4) After 24 hours, the formwork is removed and the concrete is cured in a standard or natural manner for 28 days to obtain the ultra-high performance concrete.

[0099] Example 4

[0100] The difference between Example 4 and Example 1 is that in the high-temperature bursting inhibitor, the waste non-woven disposable medical mask fiber is replaced with polypropylene fiber of the same specification and dosage.

[0101] Comparative Example

[0102] Comparative Example 1

[0103] The difference between Comparative Example 1 and Example 1 is that in the high-temperature detonation inhibitor, porous quartz powder was replaced with fly ash of the same particle size, the waste glass and waste aerated concrete composition was replaced with river sand of the same particle size, and the content of waste non-woven disposable medical mask fiber and other parameters remained unchanged. The concrete was cured for 28 days after demolding.

[0104] Comparative Example 2

[0105] The difference between Comparative Example 2 and Example 1 is that the amount of waste non-woven disposable medical mask fiber in the high-temperature bursting inhibitor was changed to 3 parts, while the rest remained unchanged. The concrete was cured for 28 days after demolding.

[0106] Comparative Example 3

[0107] The difference between Comparative Example 3 and Example 1 is that the amount of waste non-woven disposable medical mask fiber in the high-temperature bursting inhibitor was changed to 20 parts, while the rest remained unchanged. The concrete was cured for 28 days after demolding.

[0108] Comparative Example 4

[0109] The difference between Comparative Example 4 and Example 1 is that the amount of waste non-woven disposable medical mask fiber in the high-temperature cracking inhibitor was changed to 30 parts, while the rest remained unchanged. The concrete was cured for 28 days after demolding.

[0110] Comparative Example 5

[0111] The difference between Comparative Example 5 and Example 1 is that in the high-temperature detonation inhibitor, porous quartz powder was replaced with fly ash of the same particle size, the waste glass and waste aerated concrete composition was replaced with river sand of the same particle size, and the amount of waste non-woven disposable medical mask fiber was changed to 80 parts, with the rest remaining unchanged. The concrete was cured for 28 days after demolding.

[0112] Comparative Example 6:

[0113] The difference between Comparative Example 6 and Example 1 is that in the high-temperature detonation inhibitor, porous quartz powder was replaced with fly ash of the same particle size, waste aerated concrete was replaced with river sand of the same particle size, and the content of waste non-woven disposable medical mask fiber and other parameters remained unchanged. The concrete was cured for 28 days after demolding.

[0114] Comparative Example 7:

[0115] The difference between Comparative Example 7 and Example 1 is that in the high-temperature detonation inhibitor, waste glass was replaced with river sand of the same particle size, while the fiber content of waste non-woven disposable medical masks and other parameters remained unchanged. The concrete was cured for 28 days after demolding.

[0116] Performance testing

[0117] The concrete samples from each embodiment and comparative example were subjected to work-related, mechanical, and high-temperature performance tests according to T / CECS864-2021: Test Methods for Ultra-High Performance Concrete. The high-temperature bursting test was conducted in a high-temperature furnace using the ISO834 heating curve. The bursting morphology of the concrete samples from the relevant embodiments and comparative examples after high-temperature testing is shown in the figures below. Figure 2-8 As shown in Table 1, the remaining test results can be found in Table 2.

[0118]

[0119]

[0120] As shown in the performance test results of Examples 1-3, the concrete using the inhibitor of this application exhibits excellent high-temperature anti-cracking performance, and its mechanical and workability are also outstanding. This is because, compared to solutions that negatively impact concrete workability by simply adding a large amount of fiber, this application cleverly combines "zero-dimensional porous materials" with a small amount of "one-dimensional fiber materials" to form a "three-dimensional pressure-relieving network," which not only provides excellent high-temperature anti-cracking performance but also ensures that the concrete retains good workability. Further analysis of the performance of Example 4 reveals that Example 4 uses polypropylene fiber instead of waste mask fiber. The performance of Example 4 is similar to that of Example 1, indicating that the technical solution of this application can indeed make full use of waste mask fiber, and that expensive polypropylene fiber offers no advantage over the waste mask fiber used in this application.

[0121] Analysis of Comparative Example 1 revealed that replacing the pressure-relieving grid material in the high-temperature cracking inhibitor with fly ash and river sand of the same particle size caused the inhibitor to lose its "pressure-relieving grid" function during a fire. This made it difficult for the small amount of discarded mask fibers to form a "pressure-relieving network," ultimately leading to high-temperature cracking. Further analysis of Comparative Example 2 showed that due to the insufficient amount of discarded mask fibers, the "pressure-relieving network" could not be established effectively, resulting in poor high-temperature cracking resistance of the concrete.

[0122] Further analysis of the performance of Comparative Examples 3 and 4 revealed that as the amount of waste mask fibers used gradually increased, the high-temperature crack resistance of the concrete deteriorated, and its mechanical and workability properties also decreased significantly. Combined with the invention of Comparative Example 5, which simply used a large amount of waste mask fibers, the high-temperature crack resistance of the concrete improved, but its mechanical and workability properties decreased even more than those of Comparative Examples 3 and 4. This indicates that while using a large amount of waste mask fibers can improve the high-temperature crack resistance of concrete, this only considers the effect of the waste mask fibers themselves, without considering their interaction with other components, leading to a significant decrease in the mechanical and workability properties of the concrete. Combined with Comparative Examples 3-4, this demonstrates that the "pressure relief network" of this application is a clever combination of appropriate amounts of "zero-dimensional porous materials" and "one-dimensional fiber materials." Furthermore, regarding the resource reuse of waste mask fibers, this application overcomes the problem that waste mask fibers, due to their large diameter, cannot form a complete "pressure relief network" on their own. By coupling them with pressure relief grid materials, high-temperature crack resistance can be achieved without affecting the workability and mechanical properties of UHPC.

[0123] Analysis of the performance methods of Comparative Examples 6 and 7 shows that the grid material in Comparative Example 6 lacks porous material, and the grid material in Comparative Example 7 lacks molten salt inorganic phase change material. This leads to a significant decrease in the high-temperature anti-cracking performance of concrete, indicating that the grid material is very important in the formation process of the "pressure relief network" of this application. Moreover, the supporting role of the porous material at the grid points and the melting and pressure relief role of the molten salt inorganic phase change material at the grid points are both very important.

[0124] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A high temperature pop inhibitor characterized in that, It is prepared from raw materials including pressure-relieving grid material, pressure-relieving channel material, high-temperature toughening fiber, and hydration product bond-type modifier, wherein the mass ratio of the pressure-relieving grid material, pressure-relieving channel material, high-temperature toughening fiber, and hydration product bond-type modifier is 300:(6-15):(50-100):(1-5); the pressure-relieving grid material is composed of substances including porous materials and molten salt inorganic phase change materials; the pressure-relieving channel material is a molten fiber; The porous material includes nanoporous materials and porous silicate materials; the mass ratio of the nanoporous materials, porous silicate materials and molten salt inorganic phase change materials is 3:(0.5-1):(0.5-1); the nanoporous materials include one or more combinations of rice husk ash, zeolite powder and porous quartz powder; the molten salt inorganic phase change materials include one or more combinations of industrial waste glass and hollow glass microspheres, with a fineness of 10-100 μm; The hydration product bond modifier includes one or more combinations of metakaolin and finely ground coal gangue powder, with an alumina content of not less than 42% and a fineness of less than 3μm; the high-temperature toughening fiber is composed of whisker-like substances and nanofibers in a mass ratio of 1:(1~2).

2. The high temperature popcorning suppressant of claim 1, wherein, The rice husk ash is obtained by calcining rice husks at 500-750℃ and grinding them into fine powder, with a particle size of 100-800 nm.

3. The high temperature popcorning suppressant of claim 1, wherein, The zeolite powder is composed of one or more of the following: analcime, chalcogenide, calcium zeolite, flaky zeolite, sodium zeolite, mordenite, and zeolite, with a particle size of less than 3 μm.

4. The high temperature popcorπng suppressant of claim 1, wherein, The porous silicate material includes one or more combinations of aluminosilicate minerals and silicate product waste, with a fineness of 0.6–1.18 mm.

5. The high temperature popcorπ inhibitor of claim 4, wherein The aluminosilicate minerals include one or more combinations of expanded perlite, shale ceramsite, sludge ceramsite, clay ceramsite, and fly ash ceramsite; the silicate product waste includes one or more combinations of waste aerated concrete, waste foamed cement board, waste foamed concrete, and waste ceramsite foamed concrete board.

6. The high temperature popcorπ inhibitor of claim 1, wherein The pressure relief channel material includes one or more combinations of waste mask fibers, polypropylene fibers, polyvinyl alcohol fibers, and polyethylene fibers, with a length of 5 to 20 mm and a diameter of 0.01 to 1 mm.

7. The high temperature popcorning suppressant of claim 1 wherein, The whisker-like material includes one or more combinations of calcium silicate whiskers, calcium carbonate whiskers, wollastonite whiskers, mullite whiskers, and gypsum whiskers, and its aspect ratio is not less than 10; the nanofiber includes one or more combinations of α-alumina nanofibers, zirconium oxide nanofibers, and graphene oxide nanofibers, and its aspect ratio is not less than 1000.

8. The application of a high-temperature bursting inhibitor as described in any one of claims 1-7 in ultra-high performance concrete.

9. Use of the high temperature spalling inhibitor according to claim 8 in ultra-high performance concrete, characterized in that, The concrete raw materials comprise the following components by weight: 100 parts cementitious materials; 80-120 parts aggregate; 25-40 parts high-temperature cracking inhibitor; 15-20 parts steel fiber; 1-3 parts water-reducing agent; and 15-25 parts water.

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