A wear-resistant and impact-resistant high-strength rubber concrete and its preparation method

Abstract

This invention discloses a wear-resistant and impact-resistant high-strength rubber concrete and its preparation method. The wear-resistant and impact-resistant rubber concrete, by weight, comprises the following raw materials: 354 parts cement, 52 parts silica fume, 87 parts ultrafine cement, 87 parts fly ash, 417 parts sand, 1156 parts gravel, 30.2 parts rubber, 46.4 parts quartz sand, 8.7 parts water-reducing agent, and 135.7 parts water. The wear-resistant and impact-resistant rubber concrete of this invention conforms to the closest packing model and incorporates quartz sand, rubber particles, silica fume, fly ash, and ultrafine cement. The compressive strength, modulus of elasticity, flexural strength, splitting tensile strength, and impact and abrasion resistance of this invention are superior to those of ordinary rubber concrete.

Description

Technical Field

[0001] This invention relates to the field of building materials, specifically to a wear-resistant and impact-resistant high-strength rubber concrete and its preparation method. Background Technology

[0002] The mountainous regions of western my country have complex terrain, with many deep ravines and canyons, and a large number of bridges and dams. However, this region is also prone to natural disasters such as mudslides and floods. Solid debris such as mud, sand, and rocks move rapidly and in large volumes, exerting strong destructive force. Under the combined effects of mountain torrents and mudslides, dynamic loads, and cavitation, hydraulic structures such as bridge piers and columns commonly experience erosion and spalling of the reinforced concrete protective layer and cracks, causing significant safety hazards and high maintenance costs.

[0003] Since the 1980s, research on rubber concrete has been conducted abroad. Researchers have found that rubber concrete has a lower density, higher ductility, and excellent air permeability and sound insulation compared to traditional concrete. Therefore, scholars both domestically and internationally have conducted extensive research on rubber concrete. Researchers have found that adding rubber particles to concrete instead of fine aggregate can overcome some of the defects of ordinary concrete and improve some mechanical properties. However, at the same time, due to the lower elastic modulus and hydrophobicity of rubber, the incorporation of rubber particles results in weaker bond strength between the rubber particles and the cement matrix, larger pores, and changes in the stress mechanism of concrete, leading to a decrease in the compressive strength of rubber concrete. To address the strength problem of rubber concrete, Li Hailong et al. (Experimental Study on the Influence of Silica Fume on the Compressive Strength and Energy Absorption Properties of Rubber Concrete) found that smaller silica fume particles can effectively fill the pores between rubber particles and the cement matrix, thereby improving the overall compressive strength of rubber concrete. Studies by Torii et al. (Porestructure and chloride ion permeability of mortars containing silica fume) and Xing Jun et al. (Mechanical properties and durability of silica fume / waste tire rubber / concrete composites) have shown that the incorporation of silica fume can effectively improve the impermeability and permeability of rubber concrete. Qiao Weiguo et al. (Orthogonal experimental study on the optimal mix proportion of rubber particle concrete) and Wang Junjun et al. (Study on the mechanical properties of waste rubber concrete) investigated the effects of water-cement ratio and rubber admixture on the strength of rubber concrete. Li Zancheng et al. (Experimental study on the basic mechanical properties of rubber concrete) designed 12 mix proportions with 3 particle sizes and 4 admixture amounts, ultimately determining the optimal particle size and admixture range of rubber powder. Liu Jiaxing et al. (Mechanical properties and energy evolution of ultra-high strength rubber concrete) prepared ultra-high strength rubber concrete by reducing the water-cement ratio and synergistically using steel fiber reinforcement and silica fume. However, the mechanical properties of the existing rubber concrete, especially its abrasion resistance, are difficult to meet the application requirements of hydraulic engineering.

[0004] The erosion and cavitation damage caused by high-velocity sediment-laden water flow on the concrete surfaces of hydraulic structures is a common problem for spillway structures such as overflow dams, spillway tunnels (channels), and sluice gates. This is especially true when the flow velocity is high and the water carries suspended or bedload, exacerbating the erosion and cavitation. Furthermore, groundwater and rivers in the mountainous areas of western my country contain large amounts of harmful ions such as sulfate and chloride ions. Conventional bridge pier concrete materials and pier repair materials have low strength, poor impact toughness, abrasion resistance, and durability. Under the combined impact of sulfate, chloride ions, and solid debris, they cause damage to the concrete layer and corrosion of the reinforcing steel, leading to structural damage to the pier's interior. Existing bridge pier and hydraulic structure repair and reinforcement materials and methods are insufficient to meet the actual needs of engineering projects in the harsh environment of western mountainous areas. Therefore, to adapt to the erosion action of high-velocity water flow on the concrete of dams in large structures such as diversion tunnels and spillways in water conservancy projects,

[0005] There is a need to develop a high-strength, highly wear-resistant, impact-resistant, and durable ultra-high-performance concrete structural protective layer material for use in new bridge construction and old bridge repair and reinforcement projects in the mountainous areas of western my country. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a wear-resistant and impact-resistant high-strength rubber concrete and its preparation method, so as to achieve at least superior compressive strength, elastic modulus, flexural strength, splitting tensile strength and impact and abrasion resistance compared to ordinary rubber concrete.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] A wear-resistant and impact-resistant high-strength rubber concrete, by weight, comprises the following raw materials: 354 parts cement, 52 parts silica fume, 87 parts ultrafine cement, 87 parts fly ash, 417 parts sand, 1156 parts gravel, 30.2 parts rubber, 46.4 parts quartz sand, 8.7 parts water-reducing agent, and 135.7 parts water.

[0009] Furthermore, the quartz sand is high-wear-resistant quartz sand; the particle size of the quartz sand is 280-320μm, and the silica content of the quartz sand is greater than 99%.

[0010] Furthermore, the cement includes at least one of PC.42.5, PO.42.5, PC.52.5, and PO.52.5.

[0011] Furthermore, the stones include at least one of basalt stones, crushed pebbles, granite, and limestone;

[0012] And / or, the size of the stones is 4.75-16 mm.

[0013] Furthermore, the sand is secondary medium sand, including at least one of manufactured sand, ordinary river sand, and washed river sand.

[0014] Furthermore, the ultrafine cement is at least one of Grade II ultrafine silicate cement and Grade I ultrafine silicate cement.

[0015] Furthermore, the fly ash is at least one of Grade I fly ash and Grade II fly ash.

[0016] Furthermore, the water-reducing agent is a polycarboxylate water-reducing agent.

[0017] Furthermore, the silica fume is at least one of Grade I silica fume and Grade II silica fume;

[0018] And / or, the silica content of the silica ash is greater than 85%.

[0019] Furthermore, the rubber includes at least one of rubber powder and rubber granules.

[0020] Furthermore, the method for preparing the rubber concrete is characterized by comprising the following steps:

[0021] The raw materials are added to the mixing device in the following order: gravel, sand, quartz sand, rubber, cement, silica fume, fly ash, ultrafine cement, water-reducing agent, and water. The mixing is continued for 3-5 minutes.

[0022] It is worth noting that the amounts of each raw material in the rubber concrete of this invention are obtained through theoretical calculations:

[0023] The specific calculation method is as follows:

[0024] 1) It is assumed that the packing form between aggregates in concrete is approximately the state of close packing of aggregates. It is believed that concrete is filled with the gaps between the close packing of aggregates and cement paste, and that the gradation of coarse and fine aggregates should follow the Fuller gradation curve, which is conducive to achieving the closest packing of coarse and fine aggregates.

[0025] 2) Theoretical calculation of the densest packing of aggregates

[0026] ① Calculate the porosity of the material

[0027] According to (JGJ52—2006) "Standard for Quality and Testing Methods of Sand and Stone for Ordinary Concrete", the porosity of tightly packed sand and stone is calculated using the following formula, accurate to 1%.

[0028] The porosity of tightly packed sand and gravel is:

[0029] By transformation, we can obtain: V = (1 - v) c )×V c ;

[0030] In the formula: v c V represents the porosity (%) of the compacted mass; V is the apparent volume (m³) of the sand and gravel. 3 );V c The compact volume of sand and stone (m 3 ).

[0031] ② Derivation of the formula for the most compact aggregate packing

[0032] Assuming that the porosity is minimized when the two aggregates (coarse aggregate 1 and fine aggregate 2) are mixed most tightly, and that the resulting density is maximized, according to the model assumption, this means that the compact volume of fine aggregate 2 fills the voids in the tightly packed coarse aggregate 1, i.e.: V 1c -V1=V 2c Substituting into the above formula for calculating the porosity of tightly packed sand and gravel, we can obtain: That is

[0033] Furthermore, the mass ratio of coarse aggregate 1 to fine aggregate 2 at the most compact packing is: Substituting the deformed form of porosity for tightly packed sand and gravel into the equation, we obtain... Substitute again get

[0034] In the formula, ρ1 and ρ2 are the apparent densities (kg / m³) of coarse and fine aggregates, respectively. 3 ).

[0035] ρ and v 1c v 2c This can be determined through experiments based on specific aggregates. Through theoretical derivation, a formula for calculating the mass ratio when the two are mixed most tightly can be obtained.

[0036] 3) Theoretical calculation of the densest packing of powder

[0037] ① Calculation of powder mass: The concrete mix design is based on the closest packing theory to achieve the densest packing of aggregates and powder materials, resulting in concrete with small voids and a reasonable pore structure distribution. Therefore, the following relationship exists between the various phases in concrete: V a ×v=V c +V w ,

[0038] In the formula V a Let m be the volume of the aggregate system. 3 v represents the porosity of the aggregate system, in percentages; V c Let m be the volume of the multi-component powder material. 3 V w Let m be the volume of water. 3;m a For the mass of multi-element aggregates, kg; m c ρ is the mass of the multi-component powder material, in kg; ω is the water-cement ratio; ρ a The apparent density of the multi-element aggregate after optimal mixing ratio (kg / m³) 3 );ρ cm ρ represents the apparent density of a multi-component powder material after optimal mixing. w The density of water (kg / m³) 3 ).

[0039] Assuming the water-cement ratio is tested, the mass ratio of the aggregate system and the multi-component powder material can be determined by combining the above four relationships: m a :

[0040] ② The powder is most densely packed

[0041] The optimal proportion of multi-component composite cementitious materials was obtained using the minimum water requirement method for the densest packing of powders. Density represents the degree of filling of the multi-component powder material in the cementitious material system, reflecting the compactness of the cementitious material. Density is calculated using the following formula:

[0042] Where: m w Minimum water requirement for cementitious materials, kg; m b The mass of the cementitious material is expressed in kg.

[0043] ρ cm The apparent density (kg / m³) of multi-component powder materials 3 ),according to Calculate (where β1, β2, and β3 are the mass fractions of different admixtures in the cementitious material, %); ρ m1 ρ m2 ρ m3 The apparent density of each admixture is (kg / m³). 3 ).

[0044] Based on the above closest packing model, the mix proportions for foundation concrete meeting a strength of 60 MPa or higher are calculated as follows: Cement:Fly ash:Ultrafine cement, Fine sand:Aggregate:Water:Water-reducing agent = 1:0.246:0.246:1.31; 3.27:0.38:0.025, with a designed water-cement ratio of 0.35. That is, in 1 cubic meter of concrete, the specific weights of each component are: Cement 354 kg, Fly ash 87 kg, Ultrafine cement 87 kg, Fine sand 464 kg, Aggregate 1156 kg, Water 135.7 kg, and Water-reducing agent 8.7 kg. (In practical applications, it is impossible to achieve completely precise dosages. Slight deviations in dosage that have a minor impact on the mechanical properties of the concrete should also be considered as part of the closest packing model.)

[0045] Therefore, we calculated the mix proportion of the foundation concrete for the most compact packing model (the actual dosage varies slightly). Based on this, we studied the rubber and wear-resistant quartz sand admixtures and found that the optimal rubber admixture ratio was 15-20 v% and the optimal quartz sand admixture ratio was 10 v%.

[0046] The beneficial effects of this invention are:

[0047] The rubber concrete of this invention conforms to the closest packing model and incorporates a high-density rubber concrete mix proportion with quartz sand, rubber particles, silica fume, fly ash, and ultrafine cement. The compressive strength, modulus of elasticity, flexural strength, splitting tensile strength, and impact and abrasion resistance of this invention are all superior to those of ordinary rubber concrete. Attached Figure Description

[0048] Figure 1 These are the test results of the compressive strength test in the experimental examples of this invention;

[0049] Figure 2 This is the experimental result of the elastic modulus test in the experimental example of this invention. Detailed Implementation

[0050] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0051] The raw materials used in the following examples and comparative examples are as follows: cement was purchased from Dujiangyan Lafarge Cement Co., Ltd., PC.42.5 composite silicate cement 50kg / bag; silica fume was purchased from Henan Borun New Material Co., Ltd., Grade I silica fume 25kg / bag; ultrafine cement was purchased from Shandong Kangjing New Material Technology Co., Ltd., ultrafine silicate cement Grade II 25kg / bag; fly ash was purchased from Gongyi Borun Refractory Materials Co., Ltd., Grade II fly ash 25kg / bag; sand was purchased from Dujiangyan Chengjian Building Materials Co., Ltd., ordinary manufactured sand. 50kg / bag; gravel purchased from Dujiangyan Chengjian Building Materials Co., Ltd., ordinary crushed stone 50kg / bag; polycarboxylate high-performance water-reducing agent purchased from Tianjin Weihe Technology Development Co., Ltd., polycarboxylate high-performance water-reducing agent 2kg / barrel; rubber granules purchased from Dujiangyan Huayi Rubber Co., Ltd., rubber granules 1-3mm, 25kg / bag; rubber powder purchased from Dujiangyan Huayi Rubber Co., Ltd., 60 mesh; quartz sand purchased from Dujiangyan Chongqing Rongshun Mineral Products Co., Ltd., 20 mesh. The main performance parameters of all quartz sand are as follows:

[0052]

[0053] Example 1

[0054] Prepare 1m 3The wear-resistant and impact-resistant high-strength rubber concrete is made from the following raw materials: 354 kg cement, 52 kg silica fume, 87 kg ultrafine cement, 87 kg fly ash, 417 kg sand, 46.4 kg quartz sand (quartz sand replacement rate 10%), 1156 kg gravel, 135.7 kg water, 8.7 kg polycarboxylate superplasticizer, and 30.2 kg 60 mesh rubber granules. The rubber content was determined experimentally to be 30.2 kg after the basic concrete mix proportion was determined using the closest packing model, with impact and abrasion resistance as the standard.

[0055] The preparation method is as follows: 1. Weigh all materials using an electronic balance; 2. Clean the mixer; 3. Add all the gravel and sand to the mixer and mix thoroughly for 30 seconds; 4. Mix the gravel, sand, quartz sand, rubber, cement, silica fume, fly ash, and ultrafine cement thoroughly for 30 seconds; 5. Add the water-reducing agent and water to the mixer in sequence and mix thoroughly for 3 minutes; 6. Pour the mixed concrete into a mold to prepare concrete specimens.

[0056] Comparative Example 1

[0057] Prepare 1m 3 The wear-resistant and impact-resistant high-strength rubber concrete is prepared from the following raw materials: 354 kg of cement, 52 kg of silica fume, 87 kg of ultrafine cement, 87 kg of fly ash, 464 kg of sand, 1156 kg of gravel, 135.7 kg of water, 8.7 kg of polycarboxylate superplasticizer, and 30.2 kg of 60-mesh rubber granules. The preparation method is the same as in Example 1, except that quartz sand is not added.

[0058] Comparative Example 2

[0059] Prepare 1m 3 The wear-resistant and impact-resistant high-strength rubber concrete is prepared from the following raw materials: 354 kg cement, 52 kg silica fume, 87 kg ultrafine cement, 87 kg fly ash, 394 kg sand, 69.6 kg quartz sand (quartz sand replacement rate 15%), 1156 kg gravel, 135.7 kg water, 8.7 kg polycarboxylate superplasticizer, and 30.2 kg 60 mesh rubber granules. The preparation method is the same as in Example 1, except that the amount of quartz sand replacing ordinary manufactured sand is different.

[0060] Comparative Example 3

[0061] Prepare 1m 3 The wear-resistant and impact-resistant high-strength rubber concrete is prepared from the following raw materials: 354 kg cement, 52 kg silica fume, 87 kg ultrafine cement, 87 kg fly ash, 371 kg sand, 92.8 kg quartz sand (quartz sand replacement rate 20%), 1156 kg gravel, 135.7 kg water, 8.7 kg polycarboxylate superplasticizer, and 30.2 kg 60 mesh rubber granules. The preparation method is the same as in Example 1, except that the amount of quartz sand replacing ordinary manufactured sand is different.

[0062] Comparative Example 4

[0063] Prepare 1m 3 The reference concrete was prepared using the following raw materials: 354 kg of cement, 52 kg of silica fume, 87 kg of ultrafine cement, 87 kg of fly ash, 464 kg of sand, 1156 kg of gravel, 135.7 kg of water, and 8.7 kg of polycarboxylate superplasticizer. The preparation method was the same as in Example 1, except that rubber particles and quartz sand were not added.

[0064] Comparative Example 5

[0065] Prepare 1m 3 The wear-resistant and impact-resistant high-strength rubber concrete is prepared from the following raw materials: 354 kg of cement, 52 kg of silica fume, 87 kg of ultrafine cement, 87 kg of fly ash, 417 kg of sand, 46.4 kg of quartz sand (quartz sand replacement rate 10%), 1156 kg of gravel, 135.7 kg of water, 8.7 kg of polycarboxylate superplasticizer, and 30.2 kg of 60-mesh rubber powder. The preparation method is the same as in Example 1, except that the rubber particles are replaced with rubber powder with a smaller particle size.

[0066] Comparative Example 6

[0067] Prepare 1m 3 The wear-resistant and impact-resistant high-strength rubber concrete is prepared from the following raw materials: 354 kg cement, 52 kg silica fume, 87 kg ultrafine cement, 87 kg fly ash, 394 kg sand, 69.6 kg quartz sand (quartz sand replacement rate 15%), 1156 kg gravel, 135.7 kg water, 8.7 kg polycarboxylate superplasticizer, and 30.2 kg 60 mesh rubber powder. The preparation method is the same as Comparative Example 2, except that the rubber particles are replaced with rubber powder with a smaller particle size.

[0068] Comparative Example 7

[0069] Prepare 1m 3 The wear-resistant and impact-resistant high-strength rubber concrete is prepared from the following raw materials: 354 kg of cement, 52 kg of silica fume, 87 kg of ultrafine cement, 87 kg of fly ash, 371 kg of sand, 92.8 kg of quartz sand (quartz sand replacement rate 20%), 1156 kg of gravel, 135.7 kg of water, 8.7 kg of polycarboxylate superplasticizer, and 30.2 kg of 60-mesh rubber powder. The preparation method is the same as that of Comparative Example 3, except that the rubber particles are replaced with rubber powder with a smaller particle size.

[0070] Experimental Example

[0071] Concrete blocks prepared in Example 1 and Comparative Examples 1-7 were used to determine the compressive strength of 100mm×100mm×100mm cubes. Since the specimens were non-standard, the compressive strength was multiplied by a coefficient of 0.95, and the loading rate was 0.5MPa / s. Splitting tensile strength was measured by cutting 100mm×100mm×100mm cube specimens. Flexural strength was measured by cutting 100mm×100mm×400mm specimens. The modulus of elasticity was measured by cutting 100mm×200mm cylinders and using a graded loading mode, with each load being 20kN and the loading rate being 0.5kN / s.

[0072] 1) Liquidity test

[0073] The flowability of the concrete under the above five mix design was tested using a slump tester and a steel ruler. To maintain consistency in flowability results and facilitate on-site testing and pouring, the flowability test results of the high-density rubber concrete containing quartz sand were kept between 500-600 mm.

[0074] 2) Compression test

[0075] Based on previous research on the optimal dosage of rubber powder and rubber granules, 10%, 15%, and 20% of quartz sand were added to replace ordinary sand, respectively, and compressive strength tests were conducted on rubber concrete containing wear-resistant quartz sand.

[0076] Figure 1 The figure shows the compressive strength results of rubber powder concrete with four different amounts of quartz sand. As can be seen from the figure, the baseline concrete strength is 74.1 MPa. After adding rubber powder, the concrete strength decreased to 62.36 MPa (a decrease of 15.8%). With the increase of rubber particles, the concrete strength further decreased to 60.7 MPa (a decrease of 18.1%).

[0077] For concrete with added rubber powder, the compressive strength first increases and then decreases with increasing quartz sand content. When the quartz sand content reaches 20%, the strength of the rubber concrete decreases to 56.77 MPa, a reduction of approximately 9% compared to rubber concrete without quartz sand, and a reduction of 23.3% compared to the baseline concrete. Therefore, to improve the wear resistance and density of rubber concrete, it is necessary to modify and reinforce it based on rubber concrete with 20% quartz sand content.

[0078] For concrete with rubber particle content, the compressive strength trend becomes slightly more complex with increasing quartz sand content. This is mainly due to the more complex interface between the rubber particles and the wear-resistant quartz sand. When the quartz sand content is 10%, the strength of the rubber particle concrete increases by 16%, approximately twice that of the rubber powder concrete. When the quartz sand content increases from 10% to 15%, the compressive strength of the rubber particle concrete decreases to 57.51 MPa. With the quartz sand content increasing to 20%, its strength also increases slightly.

[0079] 3) The elastic modulus of rubber concrete after incorporating quartz sand was studied at the optimal dosage of rubber particles and rubber powder. The results are as follows: Figure 2 As shown. By Figure 2 It can be seen that the elastic modulus of the benchmark concrete is 35.37 GPa. Under the optimal rubber particle and rubber powder content of 20%, the elastic modulus of rubber concrete decreases slightly with the increase of rubber particle content. After adding quartz sand, the elastic modulus of rubber concrete first decreases and then increases. When the quartz sand content is 20%, its elastic modulus can be increased to the level of ordinary rubber powder concrete. However, after adding quartz sand to rubber particle concrete, when the quartz sand content is 10%, its elastic modulus decreases to 27.49 GPa. With the increase of quartz sand content, its elastic modulus gradually recovers to the level of ordinary rubber particle concrete.

[0080] In summary, the test results of concrete fluidity, compressive strength, and elastic modulus show that the addition of quartz sand will lead to complex trends in the changes of concrete compressive strength and elastic modulus. When the quartz sand content reaches 20%, the 28-day compressive strength of concrete is 56.8 MPa, and the elastic modulus is 33.02 GPa. Therefore, considering the target strength of 60 MPa and the requirement to improve the elastic modulus of rubber concrete, a 10% quartz sand content is taken as the optimal content in the mix proportion of rubber aggregate concrete.

[0081] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A wear-resistant and impact-resistant high-strength rubber concrete, characterized in that: By weight, the raw materials include: 354 parts cement, 52 parts silica fume, 87 parts ultrafine cement, 87 parts fly ash, 417 parts sand, 1156 parts gravel, 30.2 parts rubber, 46.4 parts quartz sand, 8.7 parts water-reducing agent, and 135.7 parts water. The cement is at least one of PC.42.5, PO.42.5, PC.52.5, and PO.52.5; The ultrafine cement is at least one of Grade II ultrafine silicate cement and Grade I ultrafine silicate cement; The sand is medium sand from Zone II, selected from at least one of manufactured sand, ordinary river sand, and washed river sand.

2. The rubber concrete according to claim 1, characterized in that: The stones include at least one of basalt stones, crushed pebbles, granite, and limestone; And / or, the size of the stones is 4.75-16 mm.

3. The rubber concrete according to claim 1, characterized in that: The fly ash is at least one of Grade I fly ash and Grade II fly ash.

4. The rubber concrete according to claim 1, characterized in that: The water-reducing agent is a polycarboxylate water-reducing agent.

5. The rubber concrete according to claim 1, characterized in that: The silica fume is at least one of Grade I silica fume and Grade II silica fume; And / or, the silica content of the silica ash is greater than 85%.

6. The rubber concrete according to claim 1, characterized in that: The rubber includes at least one of rubber powder and rubber granules.

7. The method for preparing rubber concrete according to claim 1, characterized in that: Includes the following steps: The raw materials are added to the mixing device in the following order: gravel, sand, quartz sand, rubber, cement, silica fume, fly ash, ultrafine cement, water-reducing agent, and water. The mixing is continued for 3-5 minutes.

Images