High-strength water-resistant anti-freezing plastering spraying mortar and preparation method thereof

Abstract

The invention relates to the technical field of building materials, and particularly discloses high-strength water-resistant anti-freezing plastering spraying mortar and a preparation method thereof. The high-strength waterproof anti-freezing plastering spraying mortar is prepared from the following raw materials in percentage by mass: 2.5 percent to 9.3 percent of high-free calcium belite sulphoaluminate clinker, 20 percent to 50 percent of gypsum, 9.4 percent to 56.5 percent of granulated blast furnace slag powder and 8 percent to 34 percent of lightweight aggregate. Through the design of the high-free-calcium belite sulphoaluminate clinker and the raw material design of the high-strength water-resistant anti-freezing plastering spraying mortar, the high-free-calcium belite sulphoaluminate clinker and the granulated blast-furnace slag powder have a synergistic effect, so that the types, the composition and the microstructure of hydration products of a gypsum-based material can be improved; the water-resistant and high-strength hydration products ettringite and C-(A)-S-H are greatly increased, and dense coating of the ettringite and C-(A)-S-H on dihydrate gypsum is realized, so that the problems of poor water resistance, poor freezing resistance and low strength of gypsum-based mortar are solved.

Description

Technical Field

[0001] The invention relates to the technical field of building materials, and in particular to a high-strength, water-resistant and frost-resistant plaster spray mortar and a preparation method thereof. Background Art

[0002] Gypsum-based plaster mortars and spray mortars are premixed dry mortars made with building gypsum (hemihydrate gypsum) as the primary binder, combined with lightweight aggregates and modified admixtures. They offer excellent properties such as environmental friendliness, rapid setting and hardening, lightweight insulation, crack resistance, and high construction efficiency. However, due to the high solubility of its hydration product, dihydrate gypsum, and the absence of colloidal hydration products, gypsum-based mortars suffer from poor water resistance and low strength. They can also pulverize with prolonged contact with water or in humid environments with high humidity. The compressive strength of existing gypsum-based mortars is approximately 4 MPa to 6 MPa, far lower than that of cement-based plaster mortars, limiting their load-bearing capacity. Furthermore, existing gypsum-based mortars also have poor water resistance and frost resistance. Therefore, gypsum-based spray plaster mortars are limited to indoor wall leveling or decorative base treatment in dry areas. They cannot be used outdoors or in load-bearing areas, nor in humid areas such as kitchens, bathrooms, and basements.

[0003] The poor water resistance and low strength of gypsum-based spray plaster mortars severely limit their application. Therefore, there is an urgent need to develop a spray plaster mortar with high-strength, water-resistant, and frost-resistant properties. In addition to addressing the technical bottlenecks of traditional gypsum-based mortars, high-strength, water-resistant, and frost-resistant spray plaster mortars can also address the large shrinkage, cracking, and high cost issues of existing cement-based spray plaster mortars, improve thermal insulation and sound insulation, and significantly improve the performance and quality of wall spray plastering projects. Furthermore, existing gypsum-based mortars have been studied for their application in a single variety: desulfurized gypsum-based building gypsum, phosphogypsum-based building gypsum, anhydrite, α-high-strength gypsum, and fluorinated gypsum. A comprehensive utilization technology applicable to all of these gypsum types has yet to be developed. Therefore, there is an urgent need to develop a high-strength, water-resistant, and frost-resistant spray plaster mortar to expand the application areas of industrial by-product gypsum, provide new technical solutions for the recycling of industrial by-product gypsum, and promote the harmless, large-scale, and resource-based utilization of industrial by-product gypsum. Summary of the Invention

[0004] In response to the above problems, the present invention provides a high-strength, water-resistant and frost-resistant plaster spray mortar and a preparation method thereof. By designing a high-free calcium belite sulphoaluminate clinker and designing the raw materials for the high-strength, water-resistant and frost-resistant plaster spray mortar, the high-free calcium belite sulphoaluminate clinker and granulated blast furnace slag powder synergistically improve the type, composition and microstructure of the hydration products of the gypsum-based material, greatly increase the water-resistant and high-strength hydration products ettringite and C-(A)-SH, and simultaneously achieve dense coating of the dihydrate gypsum by the two, thereby solving the problems of poor water resistance, poor frost resistance and low strength of gypsum-based self-leveling materials.

[0005] In order to solve the above technical problems, the technical solution provided by the present invention is: In a first aspect, the present invention provides a high-strength, water-resistant and frost-resistant plaster spray mortar, comprising the following raw materials in percentage by weight: 2.5% to 9.3% high-free calcium belite sulphoaluminate clinker, 20% to 50% gypsum, 9.4% to 56.5% granulated blast furnace slag powder, and 8% to 34% lightweight aggregate; The high-free calcium belite sulphoaluminate clinker comprises the following mineral components in percentage by mass: 25.31% to 33.27% of anhydrous calcium sulphoaluminate, 6.55% to 12.26% of free calcium sulfate, 14.82% to 19.71% of free calcium oxide, 27.27% to 33.87% of belite and 3.04% to 6.08% of iron phase.

[0006] Compared to the prior art, the high-strength, water-resistant, and frost-resistant plaster spray mortar provided by the present invention introduces a specific amount of free calcium sulfate into high-free-calcium belite sulfoaluminate clinker (referred to as clinker). Anhydrous calcium sulfoaluminate can be dissolved in the free calcium sulfate liquid phase (free calcium sulfate forms a liquid phase when calcined at high temperature), generating a mixture of amorphous anhydrous calcium sulfoaluminate and cubic anhydrous calcium sulfoaluminate. In the presence of free calcium sulfate, the activity of the cubic anhydrous calcium sulfoaluminate is much higher than the orthorhombic anhydrous calcium sulfoaluminate in conventional sulfoaluminate cement clinker. A specific amount of free calcium oxide is introduced into the clinker. The free calcium oxide has high hydration activity and reacts rapidly when exposed to water. Therefore, higher free calcium oxide and appropriate free calcium sulfate significantly enhance the activity of other minerals in the clinker and the clinker as a whole. The clinker reacts rapidly upon contact with water, generating a large amount of highly active monosulfur-type hydrated calcium sulfoaluminate (AFm) microcrystals. Since the above reactants are highly active, the generated AFm crystallites are small in size and highly active, and are in a metastable state. 2+ and SO4 2- ions, it can react rapidly to form a more stable trisulfide type hydrated calcium sulfoaluminate (also known as ettringite, AFt).

[0007] The high-strength, water-resistant and frost-resistant plaster spray mortar provided by the present invention comprises high-free calcium belite sulphoaluminate clinker and granulated blast furnace slag powder, which synergistically improve the type, composition and microstructure of gypsum hydration products. The hydration products AFt and C-(A)-SH gel with excellent water resistance are directionally grown around the dihydrate gypsum, preventing external moisture from dissolving the dihydrate gypsum, thereby significantly improving the water resistance and mechanical properties of the plaster spray mortar. Furthermore, the standard water curing strength is greater than the standard dry air curing strength.

[0008] In this invention, the dihydrate gypsum crystals formed by the addition of gypsum are densely coated with both AFt microcrystals and C-(A)-SH gel. This prevents the water-soluble dihydrate gypsum from dissolving in water even at high gypsum dosages. This solves the problems of poor water resistance, significantly reduced strength, and poor freeze-thaw resistance in gypsum-based spray plaster mortars caused by the high solubility of dihydrate gypsum. As the microstructure becomes denser, the porosity of the high-strength, water-resistant, and frost-resistant spray plaster mortar decreases, thereby gradually improving its mechanical strength.

[0009] Preferably, the belite comprises dicalcium silicate.

[0010] Preferably, the iron phase comprises tetracalcium aluminoferrite.

[0011] Preferably, the high free calcium belite sulphoaluminate clinker further comprises 5.03% to 7.66% of mixed mineral components.

[0012] For example, based on the mass content of high free calcium belite sulfoaluminate clinker being 100%, the mixed mineral components include 2% to 4% of periclase, 0.85% to 2.55% of perovskite, and 0.5% to 1.5% of alkali metal sulfate.

[0013] Preferably, the high free calcium belite sulphoaluminate clinker comprises the following oxides in percentage by mass: SiO2 9.5% to 11.8%, Al2O3 14% to 18%, CaO 55% to 58%, SO3 8% to 11% and Fe2O3 1% to 2%.

[0014] Further preferably, the high free calcium belite sulphoaluminate clinker further comprises 4% to 6.7% of mixed oxides.

[0015] Illustratively, the mixed oxide includes at least one of MgO, TiO2, Na2O, or K2O.

[0016] Preferably, the specific surface area of ​​the high free calcium belite sulphoaluminate clinker is ≥500m 2 / kg.

[0017] Preferably, the preparation method of the high free calcium belite sulphoaluminate clinker comprises the following steps: Mix limestone, bauxite and gypsum and grind them to obtain raw material; The raw material is calcined at 1200° C. to 1300° C. to obtain high-free calcium belite sulphoaluminate clinker.

[0018] The present invention provides a method for preparing high-free-calcium belite sulfoaluminate clinker. The raw material dosage is designed based on the clinker's mineral composition, thereby calculating the proportions of various oxides in the raw material. Through extensive testing, the present invention has found that the optimal firing temperature for this type of clinker is between 1200°C and 1300°C; neither too high nor too low a temperature can achieve the desired clinker mineral composition. If the firing temperature is too low, the clinker's mineral composition is insufficiently formed. If the firing temperature is too high, some mineral components are decomposed, and the desired mineral composition range cannot be achieved.

[0019] Further preferably, the mass ratio of the limestone, bauxite and gypsum is (60~71):(17~23):(12~19).

[0020] Further preferably, the chemical components in the raw material satisfy: ([CaO]-1.87×[SiO2]-1.05×[Fe2O3]-0.7×[TiO2]-0.55×[Al2O3]-0.7×[SO3]) / (100%-α)= 14.82%~19.71% (1.7×[SO3]-0.45×[Al2O3]+0.28×[Fe2O3]) / (100%-α)=6.55%~12.26% Where α is the loss on ignition of raw meal.

[0021] It should be noted that, in the present invention, [CaO] represents the mass percentage of CaO in the raw meal, [SiO2] represents the mass percentage of SiO2 in the raw meal, [Fe2O3] represents the mass percentage of Fe2O3 in the raw meal, [TiO2] represents the mass percentage of TiO2 in the raw meal, [Al2O3] represents the mass percentage of Al2O3 in the raw meal, and [SO3] represents the mass percentage of SO3 in the raw meal; α=∑mass percentage of each chemical component in the raw meal × loss on ignition of each chemical component.

[0022] The present invention ensures that the content of free calcium oxide in the prepared clinker meets the requirements by limiting {[CaO]-1.87×[SiO2]-1.4×[Fe2O3]-0.7×[TiO2]-0.73([Al2O3]-0.64×[Fe2O3])-0.7[[SO3]-([Al2O3]-0.64×[Fe2O3]) / 3.82]} / (100%-α)=14.82%-19.71%. The invention ensures that the content of free calcium oxide in the prepared clinker meets the requirements by limiting {[CaO]-1.87×[SiO2]-1.4×[Fe2O3]-0.7×[TiO2]-0.73([Al2O3]-0.64×[Fe2O3])-0.7[[SO3]-([Al2O3]-0.64×[Fe2O3]) / 3.82] / (100%-α)=6.55%-12.26%.

[0023] Further preferably, the particle size of the raw material is less than 15% after being sieved through a 0.08 mm square hole sieve.

[0024] For example, calcination is carried out in a rotary kiln, and the time from entering the kiln to leaving the kiln is 30 minutes to 60 minutes. The specific calcination time can be adjusted according to the specific conditions of different rotary kilns.

[0025] For example, after the calcination is completed, the process further includes cooling and grinding to obtain powdery high-free calcium belite sulphoaluminate clinker.

[0026] Preferably, the gypsum includes at least one of desulfurized gypsum-based building gypsum, phosphogypsum-based building gypsum, dried desulfurized gypsum, dried phosphogypsum, wet desulfurized gypsum, wet phosphogypsum, α high-strength gypsum, fluorinated gypsum, anhydrite or dihydrate gypsum.

[0027] In the present invention, desulfurized gypsum-based building gypsum and phosphogypsum-based building gypsum should meet the requirements of GB / T 9776-2022 "Building Gypsum"; desulfurized gypsum, phosphogypsum, and fluorinated gypsum should meet the requirements of GB / T 21371-2019 "Industrial By-product Gypsum Used in Cement", and phosphogypsum should also meet the requirements of GB / T 23456-2018 "Phosporum"; α high-strength gypsum should meet the requirements of JC / T 2038-2010 "α-type high-strength gypsum"; anhydrite and dihydrate gypsum should meet the requirements of GB / T 5483-2024 "Natural Gypsum". When two or more gypsums are used for compounding, there is no requirement for the amount of different gypsums. It should be noted that dried desulfurized gypsum is obtained by drying wet desulfurized gypsum, and dried phosphogypsum is obtained by drying wet phosphogypsum.

[0028] The difficulty of processing different types of gypsum varies significantly in this field. The processing of phosphogypsum is particularly challenging in China. Consequently, many current gypsum processing technologies focus on treating a single type of gypsum. However, the present invention is applicable to nearly all types of gypsum, especially industrial by-product gypsum, without requiring specific gypsum types. It offers high efficiency, energy savings, and wide applicability.

[0029] In the present invention, the granulated blast furnace slag powder should meet the requirements of GB / T 18046-2017 "Granulated blast furnace slag powder for cement, mortar and concrete" for granulated blast furnace slag powder of not less than S75 grade, and more preferably S95 grade.

[0030] Preferably, the lightweight aggregate includes at least one of perlite or vitrified microspheres.

[0031] Preferably, the high-strength, water-resistant and frost-resistant plaster spray mortar comprises the following raw materials in percentage by mass: 3% to 8% of high free calcium belite sulphoaluminate clinker, 20% to 50% of gypsum, 10% to 50% of granulated blast furnace slag powder and 10% to 30% of lightweight aggregate.

[0032] Preferably, the high-strength, water-resistant and frost-resistant plaster spray mortar further comprises the following raw materials in percentage by mass: 0-1% amorphous calcium aluminate.

[0033] Further preferably, the amorphous proportion of the amorphous calcium aluminate is ≥99.0%.

[0034] More preferably, the specific surface area of ​​the amorphous calcium aluminate is ≥500m 2 / kg.

[0035] The preferred amorphous calcium aluminate has extremely high hydration activity and can react completely within 5 minutes.

[0036] In the present invention, high-free calcium belite sulfoaluminate clinker, amorphous calcium aluminate, and granulated blast furnace slag powder have a synergistic hydration effect. The free calcium oxide in the clinker provides a suitable alkaline environment. Under the synergistic excitation of the amorphous calcium aluminate, the glass in the granulated blast furnace slag powder can be activated and stimulated. The generated AFt microcrystals induce the dissolution of substances in the glass. Under the guidance of the AFt microcrystals, the granulated blast furnace slag powder can dissolve [Al(OH)4] - and Ca 2+ , which reacts with the external gypsum to continue to generate AFt and fills the pores; the remaining Ca in the granulated blast furnace slag powder 2+ and SiO3 2- It is also gradually dissolved. The AFt crystals generated by the early clinker reaction are Ca 2+ and SiO3 2- The C-(A)-SH gel generated by the reaction provides growth sites, accelerating its formation. The C-(A)-SH gel can form a wrapping effect around the dihydrate gypsum crystals. Furthermore, these C-(A)SH gels have a low calcium-silicon ratio and a denser microstructure, which enhances their ability to encapsulate the dihydrate gypsum. As the microstructure becomes denser, the porosity of the high-strength, water-resistant, and frost-resistant spray plaster mortar decreases, thereby gradually increasing its mechanical strength.

[0037] Further preferably, the high-strength, water-resistant and frost-resistant plaster spray mortar also includes the following raw materials in percentage by mass: microspheres 0~10%, silica fume 0~3.5%, mineral admixture 0~37%, sand 0~40%, water reducer 0~0.3%, air entraining agent 0~0.02%, redispersible latex powder 0~3.5%, water-retaining thickener 0~0.13%, retarder 0~0.31%, waterproofing agent 0~0.3% and pigment 0~6%.

[0038] More preferably, the mineral admixture includes at least one of fly ash, limestone powder, steel slag powder or dolomite powder.

[0039] The present invention can use mineral admixtures in high-strength water-resistant and frost-resistant plaster spray mortar, increases the types of minerals that can be added in addition to mineral powder, and especially can effectively utilize industrial waste slag (fly ash, steel slag powder), effectively solving the problem of recycling industrial waste slag.

[0040] More preferably, the sand includes at least one of river sand, dry-mixed sand, quartz sand or machine-made sand.

[0041] More preferably, the water reducer includes at least one of a polycarboxylate water reducer, a melamine water reducer, a melamine-based high-efficiency water reducer, a lignin water reducer or a naphthalene-based water reducer.

[0042] More preferably, the air entraining agent includes at least one of a rosin resin air entraining agent, a nonionic surfactant air entraining agent, an alkylbenzene sulfonate air entraining agent, a lignin sulfonate air entraining agent or a carboxylic acid air entraining agent.

[0043] More preferably, the redispersible latex powder includes at least one of acrylic polymer powder, vinyl acetate polymer powder, vinyl acetate-ethylene copolymer powder, styrene-acrylate copolymer powder, butadiene-styrene copolymer powder or ethylene-vinyl chloride copolymer powder.

[0044] More preferably, the water-retaining thickener includes at least one of methyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose (HPMC), carboxymethyl cellulose, starch ether or hydroxyethyl methyl cellulose.

[0045] More preferably, the retarder includes at least one of citric acid, sodium citrate, sodium gluconate, zinc carbonate, tartaric acid or gypsum retarder.

[0046] More preferably, the waterproofing agent includes at least one of a stearate water repellent, a paraffin emulsion water repellent or a silicone penetrating crystalline waterproofing agent.

[0047] More preferably, the pigment includes at least one of titanium dioxide, ultramarine, red iron oxide, yellow iron oxide, black iron oxide, chromium oxide green, cobalt blue, manganese oxide, chromium oxide, ochre, mica or Prussian red.

[0048] Preferably, the compressive strength of the high-strength water-resistant and frost-resistant plaster spray mortar after 28 days of standard curing in water is 15.3 MPa~39.1 MPa.

[0049] Preferably, the high-strength water-resistant and frost-resistant plaster spray mortar has a 28-day standard curing strength in water greater than a 28-day standard curing strength in dry air.

[0050] Preferably, the frost resistance grade of the high-strength water-resistant and frost-resistant plaster spray mortar is F75 or above.

[0051] In a second aspect, the present invention provides a method for preparing the high-strength, water-resistant and frost-resistant plaster spray mortar, comprising the following steps: The raw materials of the high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed, with a water-to-material ratio of 0.25 to 0.46 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0052] The method for preparing a high-strength, water-resistant, and frost-resistant spray plaster mortar provided by the present invention balances the mortar's workability, strength, and volume deformation by limiting the water-to-material ratio. It should be noted that the amount of water used in the present invention is calculated based on the water-to-material ratio and is not included in the raw materials of the high-strength, water-resistant, and frost-resistant spray plaster mortar. The performance data, such as the strength and frost resistance grade of the high-strength, water-resistant, and frost-resistant spray plaster mortar, are based on test results after mixing with water and curing for a certain period of time.

[0053] Preferably, the water-to-material ratio is 0.27-0.4, more preferably 0.3-0.37.

[0054] The present invention has the following beneficial effects: Since the hydration product dihydrate gypsum generated by traditional gypsum-based mortar has high solubility and no colloidal hydration products, the gypsum-based mortar has low strength, poor water resistance, and extremely poor frost resistance, which can cause collapse when exposed to water in severe cases. The high-strength, water-resistant and frost-resistant plaster spray mortar provided by the present invention comprehensively optimizes the types, crystal forms and growth positions of hydration products generated in the early and late stages by adding high-free calcium belite sulphoaluminate clinker, amorphous calcium aluminate and granulated blast furnace slag powder to gypsum, and directionally grows hydration products with excellent water resistance around the dihydrate gypsum, avoiding the dissolution of the dihydrate gypsum by external moisture. Even at high gypsum dosage, the density of the gypsum-based mortar can be greatly improved, thereby further improving its water resistance, frost resistance and mechanical properties.

[0055] Through research, the present invention has found that clinker provides a slight excess of free calcium oxide. Since the calcium sulfate content in the system is moderate, the free calcium oxide, amorphous phase / cubic anhydrous calcium sulfoaluminate, and free calcium sulfate in the clinker can react rapidly to produce a large number of highly active monosulfur-type calcium sulfoaluminate hydrate (AFm) microcrystals, rather than calcium aluminate hydrate (C3AH6) or trisulfur-type calcium sulfoaluminate hydrate (i.e., ettringite, AFt). In addition, since the above reactants are all highly active, the generated AFm microcrystals are small in size, highly active, and in a metastable state. When Ca is added to the system, the reaction is complete. 2+ and SO4 2- ions, it can react quickly to generate more stable AFt; as the external gypsum hydrates and gradually generates dihydrate gypsum crystals, the surrounding Ca2+ and SO4 2- The increased ion concentration induces the AFm reaction to generate AFt crystallites around the dihydrate gypsum. These AFt crystallites gradually encapsulate the dihydrate gypsum crystals generated by the hydration of the externally added gypsum. The AFt crystallites generated in the present invention are relatively small in size and provide a good encapsulation effect, allowing the high-strength, water-resistant, and frost-resistant spray plaster mortar to rapidly form a skeleton, creating a dense microstructure and yielding high early strength. The high-strength, water-resistant, and frost-resistant spray plaster mortar of the present invention exhibits micro-expansion properties. The dihydrate gypsum crystals are doubly and densely coated with ettringite crystallites and C-(A)-SH gel, resulting in a dense structure that significantly improves the mortar's frost resistance.

[0056] Compared to traditional gypsum-based mortars, the high-strength, water-resistant, and frost-resistant spray plaster mortar provided by the present invention exhibits significantly improved water resistance, strength, and frost resistance. Conventional gypsum-based mortars have poor water resistance, with a softening coefficient (i.e., the ratio of their underwater curing strength to their air-curing strength) typically below 0.5. However, the high-strength, water-resistant, and frost-resistant spray plaster mortar provided by the present invention exhibits excellent water resistance, with a ratio of their underwater curing strength to their air-curing strength exceeding 100%. This addresses the issue of traditional gypsum-based mortars, where their underwater strength is significantly lower than their air-curing strength.

[0057] The national standard "Plaster Gypsum" (GB / T 28627-2012) requires that the compressive strength of gypsum-based plaster materials be ≥4.0 MPa. The compressive strength of existing products is generally 4 MPa to 6 MPa, and the compressive strength of existing cement plaster mortar is generally 3 MPa to 15 MPa. The high-strength, water-resistant and frost-resistant plaster spray mortar of the present invention has a compressive strength of up to 15.3 MPa to 39.1 MPa after 28 days of standard curing in water.

[0058] In the frost resistance test of the industry standard "Standard for Test Methods for Basic Properties of Building Mortar", the frost resistance grade of gypsum plaster mortar is only F25 (that is, it can withstand 25 freeze-thaw cycles), and the frost resistance grade of cement plaster mortar is only F50 (that is, it can withstand 50 freeze-thaw cycles). The frost resistance grade of the high-strength and frost-resistant plaster spray mortar of the present invention can reach F75 or above (that is, it can withstand 75 freeze-thaw cycles).

[0059] Cement plaster mortar shrinks greatly and is prone to cracking. According to the standard JGJ / T70-2009 "Standard for Test Methods for Basic Properties of Building Mortar", the shrinkage value generally exceeds 0.21%; the high-strength, water-resistant and frost-resistant plaster spray mortar of the present invention shrinks only 0.023% to 0.098%, which is much lower than the shrinkage value of cement plaster mortar, significantly reducing the risk of cracking of the mortar and greatly improving its durability.

[0060] The dry density of the high-strength water-resistant and frost-resistant plaster spray mortar in the embodiment of the present invention is 1000kg / m 3 ~1400kg / m3 and ≤1000kg / m 3 There are two major categories, with low dry density and low thermal conductivity. They can be used for internal and external walls, and have good thermal insulation performance. At the same time, they can solve the problems of cold bridges and thermal bridges in the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 This is an electron microscope photograph of the high-strength water-resistant and frost-resistant plaster spray mortar in Example 5 of the present invention after 28 days of curing; Figure 2 This is an electron microscope photograph of the high-strength water-resistant and frost-resistant plaster spray mortar in Example 6 of the present invention after 28 days of curing; Figure 3 This is an electron microscope photograph of the gypsum-based plaster spray mortar in Comparative Example 2 of the present invention after 28 days of curing. DETAILED DESCRIPTION

[0062] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0063] In the present invention, amorphous calcium aluminate was purchased from Anhui Qiming New Materials Co., Ltd., has no crystalline phase, and has a specific surface area of ​​551m 2 / kg, density is 2.95g / cm 3 ; Desulfurization gypsum-based building gypsum can be purchased from Luanxian Fuyou Renewable Resources Co., Ltd., or from Shijiazhuang Rongqiang New Building Materials Co., Ltd., phosphogypsum-based building gypsum is purchased from Shandong Shantian Chemical Technology Co., Ltd., fluorgypsum is purchased from Anhui Jinyang Fluorine Chemical Co., Ltd., anhydrite is purchased from Anhui Huantai New Materials Co., Ltd., α high-strength gypsum is purchased from Pingyi County Yuantong Gypsum Products Co., Ltd., desulfurization gypsum is purchased from Qian'an Yangang, phosphogypsum is purchased from Qinhuangdao Huaying Phosphoric Acid Co., Ltd., wet desulfurization gypsum is purchased from Qian'an Yangang, wet phosphogypsum is purchased from Qinhuangdao Huaying Phosphoric Acid Co., Ltd., dried desulfurization gypsum is made by drying wet desulfurization gypsum, and dried phosphogypsum is made by drying wet phosphogypsum; S95-grade granulated blast furnace slag powder is purchased from Qian'an Shengjiu Building Materials Co., Ltd., and S75-grade granulated blast furnace slag powder is purchased from Yunnan Xinping Yongfu Environmental Protection Co., Ltd.

[0064] Secondary fly ash was purchased from Huashan Fly Ash Distribution Office in Kaiping District; limestone powder was purchased from Tangshan Guoxin Shengmei Trading Co., Ltd., with a specific surface area of ​​253m 2 / kg. Microbeads were purchased from Beijing Zhengyuan Yixinxin Materials Co., Ltd. The water reducer was selected from naphthalene-based water reducer, melamine water reducer, C900 polycarboxylic acid water reducer, or Xindadi (XDD) polycarboxylic acid water reducer. The water repellent was ELOTEX® SEAL80, a highly active redispersible silane-based water repellent. The redispersible latex powder was selected from acrylic polymer powder, vinyl acetate-ethylene copolymer powder, or styrene-acrylate copolymer powder. PO 42.5 grade ordinary Portland cement was purchased from Tangshan Jidong Qixin Cement Co., Ltd.

[0065] Other products whose manufacturers are not specified are commercially available.

[0066] In order to better illustrate the present invention, further examples are given below.

[0067] Example 1 This embodiment provides a high-free-calcium belite sulphoaluminate clinker comprising the following mineral components by weight: 25.84% anhydrous calcium sulphoaluminate, 12.14% free calcium sulfate, 15.39% free calcium oxide, 33.29% belite, 5.78% iron phase, and 7.56% miscellaneous mineral components. The high-free-calcium belite sulphoaluminate clinker comprises the following oxides by weight: 11.60% SiO2, 14.20% Al2O3, 55.20% CaO, 10.50% SO3, 1.90% Fe2O3, and 6.60% miscellaneous oxides.

[0068] The preparation method of the high free calcium belite sulphoaluminate clinker comprises the following steps: S100. Weigh the raw materials limestone, bauxite, and gypsum according to the designed chemical composition ratio. The mass ratio of limestone, bauxite, and gypsum is 60.5:21.0:18.5. Mix and grind. After passing through a 0.08 mm square hole sieve, the residue is 13%, thereby obtaining a raw meal.

[0069] The chemical components in the raw material meet the following requirements: ([CaO]-1.87×[SiO2]-1.05×[Fe2O3]-0.7×[TiO2]-0.55×[Al2O3]-0.7×[SO3]) / (100%-α)= 15.39% (1.7×[SO3]-0.45×[Al2O3]+0.28×[Fe2O3]) / (100%-α)=12.14% Where α is the loss on ignition of raw meal.

[0070] S200, the raw material was calcined in a rotary kiln at 1250 ° C and ground to obtain a specific surface area of ​​530m 2 / kg high free calcium belite sulphoaluminate clinker.

[0071] Example 2 This embodiment provides a high-free-calcium belite sulphoaluminate clinker comprising the following mineral components by weight: 25.31% anhydrous calcium sulphoaluminate, 12.26% free calcium sulfate, 14.82% free calcium oxide, 33.87% belite, 6.08% iron phase, and 7.66% miscellaneous mineral components. The high-free-calcium belite sulphoaluminate clinker comprises the following oxides by weight: 11.80% SiO2, 14.00% Al2O3, 55.00% CaO, 10.50% SO3, 2.00% Fe2O3, and 6.70% miscellaneous oxides.

[0072] The preparation method of the high free calcium belite sulphoaluminate clinker comprises the following steps: S100. Weigh the raw materials limestone, bauxite, and gypsum according to the designed chemical composition ratio. The mass ratio of limestone, bauxite, and gypsum is 60.0:21.3:18.7. Mix and grind. After passing through a 0.08 mm square hole sieve, the residue is 12%, thereby obtaining a raw meal.

[0073] The chemical components in the raw material meet the following requirements: ([CaO]-1.87×[SiO2]-1.05×[Fe2O3]-0.7×[TiO2]-0.55×[Al2O3]-0.7×[SO3]) / (100%-α)= 14.82% (1.7×[SO3]-0.45×[Al2O3]+0.28×[Fe2O3]) / (100%-α)=12.26% Where α is the loss on ignition of raw meal.

[0074] S200, calcined the raw material in a rotary kiln at 1200℃ and ground it to obtain a specific surface area of ​​520m 2 / kg high free calcium belite sulphoaluminate clinker.

[0075] Example 3 This embodiment provides a high-free-calcium belite sulphoaluminate clinker comprising the following mineral components by weight: 32.08% anhydrous calcium sulphoaluminate, 9.57% free calcium sulfate, 16.92% free calcium oxide, 29.27% ​​belite, 6.08% iron phase, and 6.08% miscellaneous mineral components. The high-free-calcium belite sulphoaluminate clinker comprises the following oxides by weight: 10.20% SiO2, 17.40% Al2O3, 55.20% CaO, 9.80% SO3, 2.00% Fe2O3, and 5.40% miscellaneous oxides.

[0076] The preparation method of the high free calcium belite sulphoaluminate clinker comprises the following steps: S100. Weigh the raw materials limestone, bauxite, and gypsum according to the designed chemical composition ratio. The mass ratio of limestone, bauxite, and gypsum is 61.9:20.6:17.5. Mix and grind. After passing through a 0.08 mm square hole sieve, the residue is 14%, thereby obtaining a raw meal.

[0077] The chemical components in the raw material meet the following requirements: ([CaO]-1.87×[SiO2]-1.05×[Fe2O3]-0.7×[TiO2]-0.55×[Al2O3]-0.7×[SO3]) / (100%-α)= 16.92% (1.7×[SO3]-0.45×[Al2O3]+0.28×[Fe2O3]) / (100%-α)=9.57% Where α is the loss on ignition of raw meal.

[0078] S200, calcined the raw material in a rotary kiln at 1300℃ and ground it to obtain a specific surface area of ​​510m 2 / kg high free calcium belite sulphoaluminate clinker.

[0079] Example 4 This embodiment provides a high-free-calcium belite sulphoaluminate clinker comprising the following mineral components by weight: 31.92% anhydrous calcium sulphoaluminate, 6.55% free calcium sulfate, 19.71% free calcium oxide, 32.14% belite, 4.56% iron phase, and 5.12% miscellaneous mineral components. The high-free-calcium belite sulphoaluminate clinker comprises the following oxides by weight: 11.20% SiO2, 17.00% Al2O3, 58.00% CaO, 8.00% SO3, 1.50% Fe2O3, and 4.30% miscellaneous oxides.

[0080] The preparation method of the high free calcium belite sulphoaluminate clinker comprises the following steps: S100. Weigh the raw materials limestone, bauxite, and gypsum according to the designed chemical composition ratio. The mass ratio of limestone, bauxite, and gypsum is 66.4:19.3:14.3. Mix and grind. After passing through a 0.08 mm square hole sieve, the residue is 13%, thereby obtaining a raw meal.

[0081] The chemical components in the raw material meet the following requirements: ([CaO]-1.87×[SiO2]-1.05×[Fe2O3]-0.7×[TiO2]-0.55×[Al2O3]-0.7×[SO3]) / (100%-α)= 19.71% (1.7×[SO3]-0.45×[Al2O3]+0.28×[Fe2O3]) / (100%-α)=6.55% Where α is the loss on ignition of raw meal.

[0082] S200, the raw material is calcined in a rotary kiln at 1250 ° C and ground to obtain a specific surface area of ​​525m 2 / kg high free calcium belite sulphoaluminate clinker.

[0083] Example 5 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 3.1% of the high-free calcium belite sulphoaluminate clinker of Example 1, 28% of gypsum (desulfurized gypsum-based building gypsum), 20.4% of S95-grade granulated blast furnace slag powder, 8% of lightweight aggregate (perlite), 40% of sand (20% river sand, 20% dry-mixed sand), 0.08% of a water-reducing agent, 0.12% of a water-retaining thickener (0.04% starch ether, 0.08% hydroxyethyl cellulose), and 0.3% of a retarder (0.15% of sodium citrate, 0.15% of sodium neogluconate).

[0084] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.25 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0085] After curing the high-strength water-resistant and frost-resistant plaster spray mortar of this embodiment for 28 days, an electron microscope scanning test was performed. The test results are as follows: Figure 1 shown.

[0086] Example 6 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 3.1% of the high-free calcium belite sulphoaluminate clinker of Example 1, 25% of gypsum (desulfurized gypsum-based building gypsum), 20.4% of S75-grade granulated blast furnace slag powder, 8% of lightweight aggregate (perlite), 36% of sand (16% of river sand, 20% of dry-mixed sand), 0.08% of a water-reducing agent, 1% of a redispersible latex powder, 0.12% of a water-retaining thickener (0.04% of starch ether, 0.08% of hydroxyethyl cellulose), 0.3% of a retarder (0.15% of sodium citrate, 0.15% of sodium neogluconate), and 6% of a pigment (titanium dioxide).

[0087] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.25 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0088] After curing the high-strength water-resistant and frost-resistant plaster spray mortar of this embodiment for 28 days, an electron microscope scanning test was performed. The test results are as follows: Figure 2 shown.

[0089] Example 7 The present embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 3.1% of the high-free calcium belite sulphoaluminate clinker of Example 1, 28% of gypsum (α high-strength gypsum), 35.52% of S95-grade granulated blast furnace slag powder, 12% of lightweight aggregate (vitrified microspheres), 16% of sand (8% river sand, 8% dry-mixed sand), 4% of microspheres, 1% of silica fume, 0.08% of a water-reducing agent, 0.1% of a water-retaining thickener (0.02% starch ether, 0.08% hydroxyethyl cellulose), and 0.2% of a retarder (0.1% of citric acid, 0.1% of sodium neogluconate).

[0090] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.30 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0091] Example 8 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 3.1% of the high-free calcium belite sulphoaluminate clinker of Example 1, 28% of gypsum (desulfurized gypsum-based building gypsum), 35.82% of S95-grade granulated blast furnace slag powder, 8% of lightweight aggregate (perlite), 20% of sand (10% of river sand, 10% of dry-mixed sand), 4% of microbeads, 0.5% of silica fume, 0.16% of a water-reducing agent, 0.12% of a water-retaining thickener (0.02% of starch ether, 0.1% of hydroxyethyl cellulose), and 0.3% of a retarder (0.15% of sodium citrate, 0.15% of sodium neogluconate).

[0092] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.27 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0093] Example 9 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 8.55% of the high-free calcium belite sulphoaluminate clinker of Example 1, 0.45% of amorphous calcium aluminate, 20% of gypsum (phosphogypsum-based building gypsum), 56.5% of S95-grade granulated blast furnace slag powder, 14% of lightweight aggregate (perlite), 0.14% of a water-reducing agent, 0.11% of a water-retaining thickener (0.03% of starch ether and 0.08% of hydroxyethyl cellulose), and 0.25% of a retarder (0.1% of citric acid and 0.15% of sodium neogluconate).

[0094] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.35 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0095] Example 10 The present embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 2.75% of the high-free calcium belite sulfoaluminate clinker of Example 1, 0.3% of amorphous calcium aluminate, 28% of gypsum (desulfurized gypsum-based building gypsum), 34.96% of S95-grade granulated blast furnace slag powder, 9% of lightweight aggregate (perlite), 20% of sand (10% of river sand, 10% of dry-mixed sand), 4% of microbeads, 0.06% of a water-reducing agent, 0.5% of a redispersible latex powder, 0.08% of a water-retaining thickener (0.02% of starch ether, 0.06% of hydroxyethyl cellulose), 0.1% of a waterproofing agent, and 0.25% of a retarder (0.1% of citric acid, 0.15% of sodium neogluconate).

[0096] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.37 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0097] Example 11 The present embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 2.79% of the high-free calcium belite sulfoaluminate clinker of Example 1, 0.31% of amorphous calcium aluminate, 28% of gypsum (fluorgypsum), 34.6% of S95-grade granulated blast furnace slag powder, 12% of lightweight aggregate (perlite), 16% of sand (8% of river sand, 8% of dry-mixed sand), 4% of microbeads, 1% of silica fume, 0.08% of a water reducer, 1% of a redispersible latex powder, 0.08% of a water-retaining thickener (0.02% of starch ether, 0.06% of hydroxyethyl cellulose), 0.1% of a waterproofing agent, and 0.04% of a retarder (0.02% of citric acid, 0.02% of sodium neogluconate).

[0098] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.29 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0099] Example 12 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 8.1% of the high-free calcium belite sulfoaluminate clinker of Example 1, 0.9% of amorphous calcium aluminate, 20% of gypsum (desulfurized gypsum-based building gypsum), 17.33% of S95-grade granulated blast furnace slag powder, 14% of lightweight aggregate (perlite), 37% of mineral admixture (limestone powder), 0.15% of a water-reducing agent, 2% of a redispersible latex powder, 0.05% of a water-retaining thickener (0.03% of starch ether and 0.02% of hydroxyethyl cellulose), 0.2% of a waterproofing agent, and 0.27% of a retarder (0.12% of citric acid and 0.15% of sodium neogluconate).

[0100] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.40 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0101] Example 13 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 8.1% of the high-free calcium belite sulfoaluminate clinker of Example 2, 0.9% of amorphous calcium aluminate, 20% of gypsum (desulfurized gypsum-based building gypsum), 33.2% of S75-grade granulated blast furnace slag powder, 32% of lightweight aggregate (vitrified microspheres), 3.5% of silica fume, 0.2% of a water reducer, 0.01% of an air entraining agent, 1.5% of a redispersible latex powder, 0.08% of a water-retaining thickener (0.03% of starch ether and 0.05% of methyl cellulose), 0.2% of a waterproofing agent, and 0.31% of a retarder (0.18% of citric acid and 0.13% of sodium neogluconate).

[0102] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.40 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0103] Example 14 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 8.1% of the high-free calcium belite sulfoaluminate clinker of Example 2, 0.9% of amorphous calcium aluminate, 20% of gypsum (desulfurized gypsum-based building gypsum), 17.33% of S95-grade granulated blast furnace slag powder, 14% of lightweight aggregate (perlite), 37% of mineral admixture (fly ash), 0.15% of a water-reducing agent, 2% of a redispersible latex powder, 0.05% of a water-retaining thickener (0.03% of starch ether and 0.02% of hydroxyethyl cellulose), 0.2% of a waterproofing agent, and 0.27% of a retarder (0.12% of citric acid and 0.15% of sodium neogluconate).

[0104] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.40 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0105] Example 15 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 8.1% of the high-free calcium belite sulfoaluminate clinker of Example 2, 0.9% of amorphous calcium aluminate, 20% of gypsum (desulfurized gypsum-based building gypsum), 33.21% of S95-grade granulated blast furnace slag powder, 32% of lightweight aggregate (perlite), 3.5% of silica fume, 0.19% of a water reducer, 0.01% of an air entraining agent, 1.5% of a redispersible latex powder, 0.08% of a water-retaining thickener (0.03% of starch ether and 0.05% of methyl cellulose), 0.2% of a water-repellent agent, and 0.31% of a retarder (0.18% of citric acid and 0.13% of sodium neogluconate).

[0106] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.42 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0107] Example 16 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 8.1% of the high-free calcium belite sulfoaluminate clinker of Example 2, 0.9% of amorphous calcium aluminate, 40% of gypsum (desulfurized gypsum-based building gypsum), 20.17% of S95-grade granulated blast furnace slag powder, 28% of lightweight aggregate (perlite), 0.22% of a water reducer, 0.02% of an air entraining agent, 2% of a redispersible latex powder, 0.08% of a water-retaining thickener (0.03% of starch ether and 0.05% of hydroxyethyl cellulose), 0.2% of a waterproofing agent, and 0.31% of a retarder (citric acid).

[0108] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.40 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0109] Example 17 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 8.1% of the high-free calcium belite sulfoaluminate clinker of Example 2, 0.9% of amorphous calcium aluminate, 20% of gypsum (desulfurized gypsum-based building gypsum), 35.07% of S95-grade granulated blast furnace slag powder, 33% of lightweight aggregate (18% of perlite and 15% of vitrified microspheres), 0.22% of a water-reducing agent, 2% of a redispersible latex powder, 0.11% of a water-retaining thickener (0.03% of starch ether and 0.08% of hydroxyethyl cellulose), 0.3% of a waterproofing agent, and 0.3% of a retarder (0.15% of sodium citrate and 0.15% of sodium neogluconate).

[0110] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.43 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0111] Example 18 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 2.5% of the high-free calcium belite sulfoaluminate clinker of Example 2, 0.5% of amorphous calcium aluminate, 28% of gypsum (desulfurized gypsum-based building gypsum), 29.72% of S95-grade granulated blast furnace slag powder, 26% of lightweight aggregate (perlite), 8% of microspheres, 3% of silica fume, 0.2% of a water reducer, 1.5% of a redispersible latex powder, 0.08% of a water-retaining thickener (0.02% of starch ether and 0.06% of hydroxyethyl cellulose), 0.3% of a waterproofing agent, and 0.2% of a retarder (0.1% of citric acid and 0.1% of sodium neogluconate).

[0112] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.42 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0113] Example 19 The present embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 8.24% of the high-free calcium belite sulfoaluminate clinker of Example 3, 1% of amorphous calcium aluminate, 20% of gypsum (desulfurized gypsum-based building gypsum), 23% of S95-grade granulated blast furnace slag powder, 31% of lightweight aggregate (17% of perlite and 14% of vitrified microspheres), 4% of sand (2% of river sand and 2% of dry-mixed sand), 8% of microspheres, 2.5% of silica fume, 0.21% of a water reducer, 1.5% of a redispersible latex powder, 0.08% of a water-retaining thickener (0.03% of starch ether and 0.05% of hydroxyethyl cellulose), 0.2% of a waterproofing agent, and 0.27% of a retarder (0.15% of a gypsum retarder and 0.12% of sodium neogluconate).

[0114] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.40 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0115] Example 20 The present embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 2.79% of the high-free calcium belite sulfoaluminate clinker of Example 3, 0.31% of amorphous calcium aluminate, 28% of gypsum (desulfurized gypsum-based building gypsum), 19.72% of S95-grade granulated blast furnace slag powder, 27% of lightweight aggregate (17% of perlite and 10% of vitrified microspheres), 20% of sand (10% of river sand and 10% of dry-mixed sand), 0.1% of a water reducer, 1.5% of a redispersible latex powder, 0.08% of a water-retaining thickener (0.02% of starch ether and 0.06% of hydroxyethyl cellulose), 0.2% of a waterproofing agent, and 0.3% of a retarder (0.15% of sodium citrate and 0.15% of sodium neogluconate).

[0116] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.38 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0117] Example 21 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 9.24% of the high-free calcium belite sulphoaluminate clinker of Example 3, 20% of gypsum (desulfurized gypsum-based building gypsum), 23% of S95-grade granulated blast furnace slag powder, 31% of lightweight aggregate (17% of perlite and 14% of vitrified microspheres), 4% of sand (2% of river sand and 2% of dry-mixed sand), 10% of microspheres, 2.2% of silica fume, 0.21% of a water reducer, 0.08% of a water-retaining thickener (0.03% of starch ether and 0.05% of hydroxyethyl cellulose), and 0.27% of a retarder (0.15% of a gypsum retarder and 0.12% of sodium neogluconate).

[0118] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.40 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0119] Example 22 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 5.4% of the high-free calcium belite sulfoaluminate clinker of Example 3, 0.6% of amorphous calcium aluminate, 38% of gypsum (desulfurized gypsum-based building gypsum), 9.42% of S95-grade granulated blast furnace slag powder, 34% of lightweight aggregate (perlite), 10% of microspheres, 0.3% of silica fume, 0.2% of a water reducer, 0.02% of an air-entraining agent, 1.5% of a redispersible latex powder, 0.13% of a water-retaining thickener (0.03% of starch ether and 0.1% of methyl cellulose), 0.2% of a water-repellent agent, and 0.23% of a retarder (0.1% of citric acid and 0.13% of sodium neogluconate).

[0120] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.40 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0121] Example 23 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 5.4% of the high-free calcium belite sulfoaluminate clinker of Example 3, 0.6% of amorphous calcium aluminate, 45% of gypsum (desulfurized gypsum-based building gypsum), 18.7% of S95-grade granulated blast furnace slag powder, 28% of lightweight aggregate (perlite), 0.3% of a water reducer, 0.02% of an air entraining agent, 1.5% of a redispersible latex powder, 0.08% of a water-retaining thickener (0.03% of starch ether and 0.05% of hydroxyethyl cellulose), 0.2% of a waterproofing agent, and 0.2% of a retarder (citric acid).

[0122] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.40 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0123] Example 24 The present embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 8.28% of the high-free calcium belite sulfoaluminate clinker of Example 3, 0.92% of amorphous calcium aluminate, 20% of gypsum (desulfurized gypsum-based building gypsum), 25.42% of S95-grade granulated blast furnace slag powder, 28% of lightweight aggregate (15% of perlite, 13% of vitrified microspheres), 5% of sand (2.5% of river sand, 2.5% of dry-mixed sand), 8% of microspheres, 0.24% of a water reducer, 3.5% of a redispersible latex powder, 0.08% of a water-retaining thickener (0.03% of starch ether, 0.05% of hydroxyethyl cellulose), 0.3% of a waterproofing agent, and 0.26% of a retarder (0.1% of sodium citrate, 0.15% of sodium neogluconate, and 0.01% of zinc carbonate).

[0124] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.41 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0125] Example 25 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 5.4% of the high-free calcium belite sulfoaluminate clinker of Example 3, 0.6% of amorphous calcium aluminate, 50% of gypsum (desulfurized gypsum-based building gypsum), 19.51% of S95-grade granulated blast furnace slag powder, 12% of lightweight aggregate (perlite), 12% of sand (6% of river sand, 6% of dry-mixed sand), 0.18% of a water-reducing agent, 0.11% of a water-retaining thickener (0.03% of starch ether, 0.08% of hydroxyethyl cellulose), and 0.2% of a retarder (0.1% of citric acid, 0.1% of sodium neogluconate).

[0126] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.33 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0127] Example 26 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 5.4% of the high-free calcium belite sulfoaluminate clinker of Example 4, 0.6% of amorphous calcium aluminate, 50% of gypsum (anhydrite), 16.71% of S75-grade granulated blast furnace slag powder, 14% of lightweight aggregate (perlite), 12% of sand (6% of river sand, 6% of dry-mixed sand), 0.06% of a water reducer, 1% of a redispersible latex powder, 0.07% of a water-retaining thickener (0.03% of starch ether, 0.04% of hydroxyethyl cellulose), 0.1% of a waterproofing agent, and 0.06% of a retarder (0.02% of citric acid, 0.04% of sodium neogluconate).

[0128] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.32 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0129] Example 27 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 5.4% of the high-free calcium belite sulfoaluminate clinker of Example 4, 0.6% of amorphous calcium aluminate, 50% of gypsum (α high-strength gypsum), 17.61% of S95-grade granulated blast furnace slag powder, 14% of lightweight aggregate (perlite), 12% of sand (6% of river sand, 6% of dry-mixed sand), 0.08% of a water-reducing agent, 0.11% of a water-retaining thickener (0.03% of starch ether, 0.08% of hydroxyethyl cellulose), and 0.2% of a retarder (0.1% of citric acid, 0.1% of sodium neogluconate).

[0130] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.33 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0131] Example 28 This embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 5.4% of the high-free calcium belite sulfoaluminate clinker of Example 4, 0.6% of amorphous calcium aluminate, 50% of gypsum (desulfurized gypsum), 17.04% of S95-grade granulated blast furnace slag powder, 14% of lightweight aggregate (perlite), 12% of sand (6% of river sand, 6% of dry-mixed sand), 0.15% of a water reducer, 0.5% of a redispersible latex powder, 0.07% of a water-retaining thickener (0.03% of starch ether, 0.04% of hydroxyethyl cellulose), and 0.24% of a retarder (0.12% of citric acid, 0.12% of sodium neogluconate).

[0132] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.33 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0133] Example 29 The present embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 5.4% of the high-free calcium belite sulfoaluminate clinker of Example 4, 0.6% of amorphous calcium aluminate, 50% of gypsum (wet desulfurized gypsum), 15.5% of S95-grade granulated blast furnace slag powder, 14% of lightweight aggregate (perlite 7%, vitrified microspheres 7%), 12% of sand (river sand 6%, dry-mixed sand 6%), 0.15% of water reducer, 2% of redispersible latex powder, 0.07% of water-retaining thickener (starch ether 0.03%, hydroxyethyl cellulose 0.04%), 0.2% of waterproofing agent, and 0.08% of retarder (citric acid 0.04%, sodium neogluconate 0.04%).

[0134] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.33 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0135] Example 30 The present embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 5.4% of the high-free calcium belite sulfoaluminate clinker of Example 4, 0.6% of amorphous calcium aluminate, 50% of gypsum (phosphogypsum), 16.53% of S95-grade granulated blast furnace slag powder, 14% of lightweight aggregate (10% of perlite, 4% of vitrified microspheres), 12% of sand (6% of river sand, 6% of dry-mixed sand), 0.15% of a water-reducing agent, 1% of a redispersible latex powder, 0.07% of a water-retaining thickener (0.03% of starch ether, 0.04% of hydroxyethyl cellulose), 0.1% of a waterproofing agent, and 0.15% of a retarder (0.05% of citric acid, 0.05% of sodium citrate, and 0.05% of sodium neogluconate).

[0136] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.35 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0137] Example 31 The present embodiment provides a high-strength, water-resistant and frost-resistant plaster spray mortar, which is composed of the following raw materials in percentage by weight: 5.4% of the high-free calcium belite sulfoaluminate clinker of Example 4, 0.6% of amorphous calcium aluminate, 50% of gypsum (fluorgypsum), 15.91% of S95-grade granulated blast furnace slag powder, 14% of lightweight aggregate (perlite), 12% of sand (6% of river sand, 6% of dry-mixed sand), 0.2% of a water-reducing agent, 1.5% of a redispersible latex powder, 0.07% of a water-retaining thickener (0.03% of starch ether, 0.04% of hydroxyethyl cellulose), 0.2% of a waterproofing agent, and 0.12% of a retarder (0.1% of citric acid, 0.02% of sodium neogluconate).

[0138] The preparation method of high-strength water-resistant and frost-resistant plaster spray mortar comprises the following steps: The raw materials of the above-mentioned high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.33 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

[0139] Comparative Example 1 This comparative example provides a cement-based plaster spray mortar, which is composed of the following raw materials in percentage by weight: 19% of PO42.5 grade ordinary Portland cement, 5.3% of fly ash, 75.06% of river sand, 0.21% of water reducer, 0.11% of air entraining agent and 0.32% of hydroxyethyl cellulose.

[0140] The preparation method of cement-based plaster spray mortar comprises the following steps: The raw materials of the above-mentioned cement-based plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.45 to obtain cement-based plaster spray mortar.

[0141] Comparative Example 2 This comparative example provides a gypsum-based plaster spray mortar, which is composed of the following raw materials in percentage by weight: 45% desulfurized gypsum-based building gypsum, 23.22% limestone powder, 28% perlite, 0.12% water reducer, 0.3% waterproofing agent, 0.06% starch ether, 0.1% hydroxyethyl cellulose, 0.2% citric acid and 3% glue powder.

[0142] The preparation method of gypsum-based plaster spray mortar comprises the following steps: The raw materials of the above-mentioned gypsum-based plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.40 to obtain gypsum-based plaster spray mortar.

[0143] After curing the gypsum-based spray mortar for 28 days, an electron microscope scanning test was performed. The test results are as follows: Figure 3 shown.

[0144] Comparative Example 3 This comparative example provides a gypsum-based sprayable plaster mortar, comprising the following raw materials by weight (similar to Example 5, except for the different mineral components in the clinker): 3.1% high-belite sulphoaluminate cement clinker, 28% gypsum (desulfurized gypsum-based building gypsum), 20.4% S95-grade granulated blast furnace slag powder, 8% lightweight aggregate (perlite), 40% sand (20% river sand, 20% dry-mixed sand), 0.08% water-reducing agent, 0.12% water-retaining thickener (0.04% starch ether, 0.08% hydroxyethyl cellulose), and 0.3% retarder (0.15% sodium citrate, 0.15% sodium neogluconate). The high-belite sulphoaluminate cement clinker comprises the following mineral components by weight: 28% anhydrous calcium sulphoaluminate, 16% free calcium sulfate, 3% free calcium oxide, 45% belite, 6% iron phase, and 2% miscellaneous mineral components.

[0145] The preparation method of gypsum-based plaster spray mortar comprises the following steps: The raw materials of the above-mentioned gypsum-based plaster spray mortar are mixed and then water is added and mixed at a water-to-material ratio of 0.25 to obtain gypsum-based plaster spray mortar.

[0146] Verification test The mortars provided in Examples 5 to 31 and Comparative Examples 1 to 3 were subjected to performance tests, and the test results are shown in Tables 1 and 2.

[0147] The test methods, specifications and product standards adopted are: Bulk density and water retention rate tests are carried out in accordance with the national standard GB / T28627-2023 "Plastering Gypsum", dry strength tests are carried out in accordance with the national standard GB / T 17669.3-1999 "Determination of Mechanical Properties of Building Gypsum", wet strength tests are carried out in accordance with GB / T 17671-2021 "Test Method for Strength of Cement Mortar (ISO Method)", shrinkage rate, tensile bond strength and frost resistance tests are carried out in accordance with the industry standard JGJ / T70-2009 "Standard for Test Methods for Basic Properties of Building Mortar".

[0148] Table 1 Performance test results of mortars of embodiment and comparative example 1

[0149] Table 2 Performance test results of mortars of embodiment and comparative example 2

[0150] As can be seen from the table, the high-strength, water-resistant, and frost-resistant spray plaster mortars in Examples 5 to 31 of the present invention have a 28-day dry compressive strength of 13.5 MPa to 35.9 MPa, and a 28-day wet compressive strength of 15.3 MPa to 39.1 MPa. The ratio of 28-day wet strength to dry strength exceeds 100%. The cement-based mortar in Comparative Example 1 has a 28-day dry compressive strength and wet compressive strength of only 11.9 MPa and 12.2 MPa, respectively. Given that the bulk density of the cement-based mortar is approximately twice that of the high-strength, water-resistant, and frost-resistant spray plaster mortar, the compressive strength of Comparative Example 1 is far lower than that of the Examples. The raw materials and proportions of the gypsum-based mortar in Comparative Example 2 are similar to those in Example 23. The perlite content and water-cement ratio in Comparative Example 2 and Example 23 are identical (aside from the cementitious material, the most significant factors influencing strength are the perlite content and water-cement ratio). While the gypsum content is also identical, the present invention significantly improves the mortar's strength and water resistance by adding appropriate amounts of high-free-calcium belite sulphoaluminate clinker and granulated blast furnace slag powder. The 28-day dry strength of Comparative Example 2 is 4.5 MPa, while that of Example 23 is 13.8 MPa. The 28-day wet strength of Comparative Example 2 is 2.2 MPa (strength decreases exponentially after wet curing), while that of Example 23 is 15.6 MPa. The 28-day wet strength to dry strength ratio of Comparative Example 2 is 48.9%, while that of Example 23 is a whopping 113%. Comparative Example 3 and Example 5 use the same raw material ratio, but different clinkers. By using clinker with optimized mineral components, the present invention significantly improves the mechanical properties of the mortar. The 28-day dry strength of Comparative Example 3 is 16.3 MPa, while that of Example 5 is 26.9 MPa. The 28-day wet strength of Comparative Example 3 is 15.7 MPa, while that of Example 5 is 29.4 MPa. The 28-day wet strength to dry strength ratio of Comparative Example 3 is 96%, while that of Example 5 is as high as 109%. The above data and comparison demonstrate that the high-strength, water-resistant, and frost-resistant spray plaster mortar of the present invention has high strength and excellent water resistance. The compressive strength after 28 days of standard curing in water is greater than that after 28 days of standard curing in the air.

[0151] The 28-day shrinkage of the high-strength, water-resistant, and frost-resistant spray plaster mortars in Examples 5 to 31 of the present invention was only 0.023% to 0.098%. The 28-day shrinkage of the cement-based mortar in Comparative Example 1 was as high as 0.21%, more than 10 times that of the high-strength, water-resistant, and frost-resistant spray plaster mortar. These data and comparisons demonstrate that the high-strength, water-resistant, and frost-resistant spray plaster mortar of the present invention exhibits superior crack resistance compared to cement mortar.

[0152] The 28-day tensile bond strengths of the high-strength, water-resistant, and frost-resistant spray plaster mortars in Examples 5 to 31 of the present invention ranged from 0.66 MPa to 1.26 MPa. The 28-day tensile bond strengths of the mortars in Comparative Examples 1 to 3 were only 0.37 MPa, 0.26 MPa, and 0.68 MPa, respectively. These data and comparisons demonstrate that the high-strength, water-resistant, and frost-resistant spray plaster mortars of the present invention exhibit significant advantages in terms of substrate bonding strength.

[0153] In Examples 5 to 31 of the present invention, the strength loss rate of the high-strength water-resistant and frost-resistant plaster spray mortar after 75 freeze-thaw cycles was only 9.69% to 23.75%, and the mass loss rate was only 2.10% to 3.96%. The strength loss rate and mass loss rate of the cement mortar in Comparative Example 1 after 50 freeze-thaw cycles reached 24.5% and 4.61%, respectively. The strength loss rate and mass loss rate of the cement mortar in Comparative Example 3 after 50 freeze-thaw cycles reached 22.15% and 4.36%, respectively. Although the bulk density of cement-based mortar far exceeds that of high-strength water-resistant and frost-resistant plaster spray mortar, the frost resistance of Comparative Examples 1 and 3 is inferior to that of the embodiment. The gypsum-based mortar in Comparative Example 2 was completely crushed and had no strength after 5 freeze-thaw cycles, which also verified that the frost resistance of traditional gypsum-based mortar is poor.

[0154] In summary, the high-strength, water-resistant and frost-resistant plaster spray mortar provided by the present invention has better performance than cement-based mortar and gypsum-based mortar in all aspects. It can be widely used in interior and exterior wall plaster spraying of buildings, and is especially suitable for cold, rainy areas or areas with high performance requirements. It has lower cost and broad prospects.

[0155] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-strength, water-resistant and frost-resistant plaster spray mortar, characterized in that: The raw materials include the following percentages by weight: high free calcium belite sulphoaluminate clinker 2.5% to 9.3%, gypsum 20% to 50%, granulated blast furnace slag powder 9.4% to 56.5% and lightweight aggregate 8% to 34%; The high-free calcium belite sulphoaluminate clinker comprises the following mineral components in percentage by mass: 25.31% to 33.27% of anhydrous calcium sulphoaluminate, 6.55% to 12.26% of free calcium sulfate, 14.82% to 19.71% of free calcium oxide, 27.27% to 33.87% of belite and 3.04% to 6.08% of iron phase.

2. The high-strength, water-resistant and frost-resistant plaster spray mortar according to claim 1, characterized in that: The high-free calcium belite sulphoaluminate clinker comprises the following oxides in percentage by mass: SiO2 9.5%-11.8%, Al2O3 14%-18%, CaO 55%-58%, SO3 8%-11% and Fe2O3 1%-2%.

3. The high-strength water-resistant and frost-resistant plaster spray mortar according to claim 1, characterized in that: The preparation method of the high-free-calcium belite sulphoaluminate clinker comprises the following steps: Mix limestone, bauxite and gypsum and grind them to obtain raw material; The raw material is calcined at 1200° C. to 1300° C. to obtain high-free calcium belite sulphoaluminate clinker.

4. The high-strength, water-resistant and frost-resistant plaster spray mortar according to claim 3, characterized in that: The chemical components in the raw material meet the following requirements: ([CaO]-1.87×[SiO2]-1.05×[Fe2O3]-0.7×[TiO2]-0.55×[Al2O3]-0.7×[SO3]) / (100%-α)= 14.82%~19.71% (1.7×[SO3]-0.45×[Al2O3]+0.28×[Fe2O3]) / (100%-α)=6.55%~12.26% Where α is the loss on ignition of raw meal.

5. The high-strength water-resistant and frost-resistant plaster spray mortar according to claim 1, characterized in that: The gypsum includes at least one of desulfurized gypsum-based building gypsum, phosphogypsum-based building gypsum, dried desulfurized gypsum, dried phosphogypsum, wet desulfurized gypsum, wet phosphogypsum, α high-strength gypsum, fluorinated gypsum, anhydrite or dihydrate gypsum; The lightweight aggregate includes at least one of perlite or vitrified microspheres.

6. The high-strength, water-resistant and frost-resistant plaster spray mortar according to claim 1, characterized in that: The high-strength, water-resistant and frost-resistant plaster spray mortar further comprises the following raw materials in percentage by weight: 0-1% amorphous calcium aluminate.

7. The high-strength, water-resistant and frost-resistant plaster spray mortar according to claim 6, characterized in that: The amorphous ratio of the amorphous calcium aluminate is ≥99.0%, and the specific surface area is ≥500m 2 / kg.

8. The high-strength, water-resistant and frost-resistant plaster spray mortar according to claim 1, characterized in that: The high-strength, water-resistant and frost-resistant plaster spray mortar also includes the following raw materials in percentage by mass: 0-10% microbeads, 0-3.5% silica fume, 0-37% mineral admixture, 0-40% sand, 0-0.3% water reducer, 0-0.02% air entraining agent, 0-3.5% redispersible latex powder, 0-0.13% water-retaining thickener, 0-0.31% retarder, 0-0.3% waterproofing agent and 0-6% pigment.

9. The high-strength, water-resistant and frost-resistant plaster spray mortar according to claim 8, characterized in that: The mineral admixture includes at least one of fly ash, limestone powder, steel slag powder or dolomite powder; The sand includes at least one of river sand, dry-mixed sand, quartz sand or machine-made sand; The water reducer includes at least one of a polycarboxylate water reducer, a melamine water reducer, a melamine-based high-efficiency water reducer, a lignin water reducer or a naphthalene-based water reducer; The air entraining agent includes at least one of a rosin resin air entraining agent, a nonionic surfactant air entraining agent, an alkylbenzene sulfonate air entraining agent, a lignin sulfonate air entraining agent or a carboxylic acid air entraining agent; The redispersible latex powder includes at least one of acrylic polymer rubber powder, vinyl acetate polymer rubber powder, vinyl acetate-ethylene copolymer rubber powder, styrene-acrylate copolymer rubber powder, butadiene-styrene copolymer rubber powder or ethylene-vinyl chloride copolymer rubber powder; The water-retaining thickener comprises at least one of methyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, carboxymethyl cellulose, starch ether or hydroxyethyl methyl cellulose; The retarder comprises at least one of citric acid, sodium citrate, sodium gluconate, zinc carbonate, tartaric acid or gypsum retarder; The waterproofing agent includes at least one of a stearate water repellent, a paraffin emulsion water repellent or an organosilicon penetrating crystallization water repellent; The pigment includes at least one of titanium dioxide, ultramarine, red iron oxide, yellow iron oxide, black iron oxide, chromium oxide green, cobalt blue, manganese oxide, chromium oxide, ochre, mica or Prussian red.

10. The high-strength, water-resistant and frost-resistant plaster spray mortar according to any one of claims 1 to 9, characterized in that: The compressive strength of the high-strength water-resistant and frost-resistant plaster spray mortar after 28 days of standard curing in water is 15.3MPa~39.1MPa; The 28-day standard curing strength in water of the high-strength water-resistant and frost-resistant plaster spray mortar is greater than the 28-day standard curing strength in dry air; The frost resistance grade of the high-strength water-resistant and frost-resistant plaster spray mortar is F75 or above.

11. The method for preparing the high-strength, water-resistant and frost-resistant plaster spray mortar according to any one of claims 1 to 10, characterized in that: The following steps are involved: The raw materials of the high-strength water-resistant and frost-resistant plaster spray mortar are mixed and then water is added and mixed, with a water-to-material ratio of 0.25-0.46 to obtain the high-strength water-resistant and frost-resistant plaster spray mortar.

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