C140 high-strength concrete and preparation method thereof

Abstract

The invention relates to the technical field of concrete preparation, and discloses C140 high-strength concrete and a preparation method thereof.The C140 high-strength concrete comprises main materials, auxiliary materials and additives, and the main materials further comprise 500 parts of cement, 1050 parts of coarse aggregate and 700 parts of fine aggregate; the auxiliary materials further comprise 50 parts of silica fume, 100 parts of ground slag powder, 15 parts of steel fibers, 3 parts of carbon fibers, 1 part of polypropylene fibers and 15 parts of nano silicon dioxide; the additives further comprise 35 parts of epoxy resin emulsion, 20 parts of acrylic emulsion, 2 parts of a silane coupling agent, 5 parts of a sodium sulfate early strength agent, 0.5 part of a sodium gluconate retarder and 8-12 parts of a water reducing agent, the coarse aggregate is gravel and is continuously graded by 5-20 mm, the crushing index is smaller than 10%, and the needle-sheet-shaped content is smaller than 5%. Steel, carbon and polypropylene fibers are interwoven to form a tough network, toughness is improved, impact and vibration are resisted, the anti-seismic property is effectively improved, the structure can be stabilized, gaps are filled through multiple emulsions and coupling agents, all the components are tightly connected, the emulsion and the coupling agents cooperate with reinforcing steel bars, and the composite material can be used for a large-span structure to solve the structural problem.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete preparation, and in particular to a C140 high-strength concrete and a preparation method thereof. Background Art

[0002] High-strength concrete refers to concrete with a high cubic compressive strength, which is widely used in high-rise buildings, long-span bridges and other places with strict requirements on bearing capacity;

[0003] However, some existing high-strength concretes have the problem of insufficient toughness and seismic resistance. The reason is that the traditional high-strength concrete formula focuses on the pursuit of high strength, often over-relying on cement and aggregates, ignoring the addition of toughening ingredients such as fiber, and failing to form an effective crack-resistant system. When subjected to external impact or earthquake, cracks tend to spread rapidly, leading to brittle structural failure. In addition, since the internal structure of high-strength concrete is relatively dense, although it is beneficial to strength, it reduces deformation capacity and has poor energy dissipation. Moreover, if excessive vibration and improper maintenance are carried out during construction, internal defects will be aggravated and overall performance will be weakened. Summary of the invention

[0004] The object of the present invention is to provide a C140 high-strength concrete and a preparation method thereof, which can effectively solve the problems in the background technology.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] A C140 high-strength concrete and a preparation method thereof, wherein each cubic meter of concrete comprises the following main materials, auxiliary materials and additives:

[0007] The main materials also include 500 parts of cement, 1050 parts of coarse aggregate, and 700 parts of fine aggregate;

[0008] The auxiliary materials also include 50 parts of silica fume, 100 parts of ground slag powder, 15 parts of steel fiber, 3 parts of carbon fiber, 1 part of polypropylene fiber, and 15 parts of nano silicon dioxide;

[0009] The additives also include 35 parts of epoxy resin emulsion, 20 parts of acrylic emulsion, 2 parts of silane coupling agent, 5 parts of sodium sulfate early strength agent, 0.5 parts of sodium gluconate retarder, and 8-12 parts of water reducing agent.

[0010] As a further preferred embodiment of the present invention, the coarse aggregate is crushed stone with a continuous grading of 5-20MM, a crushing index of less than 10%, and a needle-like content of less than 5%. The crushed stone constitutes the skeleton of the concrete and withstands pressure. The fine aggregate is medium sand with a fineness modulus of 2.6-3.0 and a mud content of less than 2%. The medium sand fills the voids in the coarse aggregate to improve workability.

[0011] As a further preferred embodiment of the present invention, the silica fume has a specific surface area of ​​15000-25000m 2 / kg, the activity index after mixing with cement is ≥85%, and the free silicon oxide content is <1%;

[0012] The ground slag powder has a specific surface area of ​​400-600m 2 / kg, the activity index after mixing with cement is ≥75%, and the chloride ion content is <0.06%.

[0013] As a further preferred embodiment of the present invention, the steel fiber is selected to have a length of 30-50 mm, a diameter of 0.5-0.8 mm, and a volume content of about 1%, thereby enhancing tensile strength and toughness and improving fatigue resistance. The polypropylene fiber is selected to have a length of 12-19 mm, which can improve crack resistance and bridge cracks.

[0014] A method for preparing C140 high-strength concrete:

[0015] S1. Turn on the mixer. Before pouring the materials in, check whether the inside of the mixer is clean and whether there are any residual concrete lumps or debris. If there are any, clean them up to avoid affecting the quality of this mixing. Then, slowly pour the well-proportioned cement, silica fume, ground slag powder, and nano-silicon dioxide into the mixer in sequence, start the low-speed mixing mode, control the speed at 15-20r / min, and dry mix for 2 to 3 minutes. The operator needs to pay attention to the mixing situation at all times. The tumbling state of the powdered materials can be checked through the observation hole to ensure that they are fully mixed and evenly mixed to avoid dry powder accumulation or unevenly mixed corners. If dry powder agglomerates, the mixing time should be appropriately extended by 30 to 60 seconds until the dry powder is completely dispersed and the color is uniform.

[0016] S2. After the dry mixing operation in step S1 is completed, the coarse and fine aggregates that have been cleaned in advance and dried or drained are added to the mixer. When adding, they should be poured slowly and evenly from the feed port to prevent the mixer load from increasing instantly or local material accumulation due to the concentrated dumping of aggregates. After all the aggregates are added, the mixer speed is adjusted to 20-25r / min, and the dry mixing is continued for 2 minutes. During this process, pay attention to the rolling of the aggregates in the mixer. You should see that the surface of the aggregates is gradually covered with a uniform layer of powder. If it is found that the powder is unevenly attached to the surface of some aggregates, the mixing can be appropriately suspended, and a shovel is used to manually turn it over, and then the mixing is continued to ensure that each aggregate is fully coated.

[0017] S3. Slowly and evenly sprinkle the pre-dispersed steel fiber, carbon fiber and polypropylene fiber into the mixer. The sprinkling speed should be moderate, neither too fast to cause the fibers to clump together, nor too slow to affect the mixing efficiency. After all the fibers are sprinkled in, adjust the mixer speed to 20-25r / min and dry mix for 1 to 2 minutes.

[0018] S4. Slowly add the pre-mixed epoxy resin emulsion, acrylic emulsion and diluted silane coupling agent mixture into the mixer. When adding, the mixture can be evenly and continuously injected into the mixer according to the established flow rate through a graduated separatory funnel or a metering pump. At the same time, turn on the mixer and increase the speed to 25-30r / min. During the stirring process of 3 to 5 minutes, the emulsion will gradually wrap around the surface of the powder and aggregate. At this time, the color of the concrete will gradually become more moist and begin to show better adhesion. If the emulsion is found to be unevenly wrapped and dry powder is exposed, the stirring time can be appropriately extended by 1 to 2 minutes to ensure that the materials are mixed evenly.

[0019] S5. Pour the dissolved sodium sulfate early strength agent solution and sodium gluconate retarder solution into the mixer. Pour slowly and evenly to avoid the solution flowing into one place and causing excessive concentration of local admixtures. After all the solutions are poured in, continue stirring for 1 to 2 minutes to evenly distribute the admixtures. The effect of the admixtures can be preliminarily judged by detecting the temperature change of the mixed material. If the temperature rise or fall rate is abnormal, check whether the amount and dissolution of the admixtures are correct. Keep the mixer speed at 25-30rmin.

[0020] S6. Finally, add the water reducer and the remaining water. The amount of water added is fine-tuned according to the pre-estimated workability of the concrete. First, add 80% to 90% of the estimated water, start the mixer, and stir for 5 to 8 minutes. Initially, the speed can be controlled at 25-30r / min. As the mixture gradually becomes uniform, the speed can be increased to 30-35r / min as needed, until the concrete achieves uniform and good workability without obvious segregation or water seepage.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] In the present invention, steel, carbon, and polypropylene fibers are interwoven into a tough network to increase toughness, resist impact and vibration, effectively improve seismic performance, stabilize the structure, and fill the gaps with a variety of emulsions and coupling agents to tightly connect the components. It works with steel bars and is used in large-span structures to prevent structural problems. DETAILED DESCRIPTION

[0023] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0024] The present invention provides a C140 high-strength concrete and a preparation method thereof, wherein each cubic meter of concrete comprises the following main materials, auxiliary materials and additives:

[0025] The main materials also include 500 parts of cement, 1050 parts of coarse aggregate, and 700 parts of fine aggregate;

[0026] The auxiliary materials also include 50 parts of silica fume, 100 parts of ground slag powder, 15 parts of steel fiber, 3 parts of carbon fiber, 1 part of polypropylene fiber, and 15 parts of nano silicon dioxide;

[0027] The additives also include 35 parts of epoxy resin emulsion, 20 parts of acrylic emulsion, 2 parts of silane coupling agent, 5 parts of sodium sulfate early strength agent, 0.5 parts of sodium gluconate retarder, and 8-12 parts of water reducing agent.

[0028] The coarse aggregate is crushed stone with a continuous gradation of 5-20 mm, a crushing index of <10%, and a needle-like content of <5%. The crushed stone constitutes the skeleton of the concrete and bears pressure. The fine aggregate is medium sand with a fineness modulus of 2.6-3.0 and a mud content of <2%. The medium sand fills the gaps in the coarse aggregate and improves workability. The silica fume is selected with a specific surface area of ​​15000-25000m 2 / kg, the activity index after mixing with cement is ≥85%, and the free silicon oxide content is <1%;

[0029] The ground slag powder has a specific surface area of ​​400-600m 2 / kg, the activity index after mixing with cement is ≥75%, the chloride ion content is <0.06%, and the specific surface area of ​​the silica fume is 15000-25000m 2 / kg, the activity index after mixing with cement is ≥85%, and the free silicon oxide content is <1%.

[0030] The ground slag powder has a specific surface area of ​​400-600m 2 / kg, the activity index after mixing with cement is ≥75%, and the chloride ion content is <0.06%.

[0031] A method for preparing C140 high-strength concrete:

[0032] S1. Turn on the mixer. Before pouring the materials in, check whether the inside of the mixer is clean and whether there are any residual concrete lumps or debris. If there are any, clean them up to avoid affecting the quality of this mixing. Then, slowly pour the well-proportioned cement, silica fume, ground slag powder, and nano-silicon dioxide into the mixer in sequence, start the low-speed mixing mode, control the speed at 15-20r / min, and dry mix for 2 to 3 minutes. The operator needs to pay attention to the mixing situation at all times. The tumbling state of the powdered materials can be checked through the observation hole to ensure that they are fully mixed and evenly mixed to avoid dry powder accumulation or unevenly mixed corners. If dry powder agglomerates, the mixing time should be appropriately extended by 30 to 60 seconds until the dry powder is completely dispersed and the color is uniform.

[0033] S2. After the dry mixing operation in step S1 is completed, the coarse and fine aggregates that have been cleaned in advance and dried or drained are added to the mixer. When adding, they should be poured slowly and evenly from the feed port to prevent the mixer load from increasing instantly or local material accumulation due to the concentrated dumping of aggregates. After all the aggregates are added, the mixer speed is adjusted to 20-25r / min, and the dry mixing is continued for 2 minutes. During this process, pay attention to the rolling of the aggregates in the mixer. You should see that the surface of the aggregates is gradually covered with a uniform layer of powder. If it is found that the powder is unevenly attached to the surface of some aggregates, the mixing can be appropriately suspended, and a shovel is used to manually turn it over, and then the mixing is continued to ensure that each aggregate is fully coated.

[0034] S3. Slowly and evenly sprinkle the pre-dispersed steel fiber, carbon fiber and polypropylene fiber into the mixer. The sprinkling speed should be moderate, neither too fast to cause the fibers to clump together, nor too slow to affect the mixing efficiency. After all the fibers are sprinkled in, adjust the mixer speed to 20-25r / min and dry mix for 1 to 2 minutes.

[0035] S4. Slowly add the pre-mixed epoxy resin emulsion, acrylic emulsion and diluted silane coupling agent mixture into the mixer. When adding, the mixture can be evenly and continuously injected into the mixer according to the established flow rate through a graduated separatory funnel or a metering pump. At the same time, turn on the mixer and increase the speed to 25-30r / min. During the stirring process of 3 to 5 minutes, the emulsion will gradually wrap around the surface of the powder and aggregate. At this time, the color of the concrete will gradually become more moist and begin to show better adhesion. If the emulsion is found to be unevenly wrapped and dry powder is exposed, the stirring time can be appropriately extended by 1 to 2 minutes to ensure that the materials are mixed evenly.

[0036] S5. Pour the dissolved sodium sulfate early strength agent solution and sodium gluconate retarder solution into the mixer. Pour slowly and evenly to avoid the solution flowing into one place causing excessive concentration of local admixtures. After all the solutions are poured in, continue stirring for 1 to 2 minutes to evenly distribute the admixtures. The effect of the admixtures can be preliminarily judged by detecting the temperature change of the mixed material. If the temperature rise or fall rate is abnormal, check whether the amount and dissolution of the admixtures are correct. Keep the mixer speed at 25-30R / MIN.

[0037] S6. Finally, add the water reducer and the remaining water. The amount of water added is fine-tuned according to the pre-estimated workability of the concrete. First, add 80% to 90% of the estimated water, start the mixer, and stir for 5 to 8 minutes. Initially, the speed can be controlled at 25-30r / min. As the mixture gradually becomes uniform, the speed can be increased to 30-35r / min as needed, until the concrete achieves uniform and good workability without obvious segregation or water seepage.

[0038] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A C140 high-strength concrete and a preparation method thereof, characterized in that: Each cubic meter of concrete includes the following main materials, auxiliary materials and additives: The main materials also include 500 parts of cement, 1050 parts of coarse aggregate, and 700 parts of fine aggregate; The auxiliary materials also include 50 parts of silica fume, 100 parts of ground slag powder, 15 parts of steel fiber, 3 parts of carbon fiber, 1 part of polypropylene fiber, and 15 parts of nano silicon dioxide; The additives also include 35 parts of epoxy resin emulsion, 20 parts of acrylic emulsion, 2 parts of silane coupling agent, 5 parts of sodium sulfate early strength agent, 0.5 parts of sodium gluconate retarder, and 8-12 parts of water reducing agent.

2. The C140 high-strength concrete and preparation method thereof according to claim 1, characterized in that: The coarse aggregate is crushed stone with a continuous gradation of 5-20 mm, a crushing index of less than 10%, and a needle-like content of less than 5%. The fine aggregate is medium sand with a fineness modulus of 2.6-3.0 and a mud content of less than 2%.

3. The C140 high-strength concrete and preparation method thereof according to claim 1, characterized in that: The silica fume has a specific surface area of ​​15000-25000m 2 / kg, the activity index after mixing with cement is ≥85%, and the free silicon oxide content is <1%; The ground slag powder has a specific surface area of ​​400-600m 2 / kg, the activity index after mixing with cement is ≥75%, and the chloride ion content is <0.06%.

4. The method for preparing C140 high-strength concrete according to claim 1, characterized in that: The steel fiber is selected to have a length of 30-50 mm, a diameter of 0.5-0.8 mm, and a volume content of about 1%, so as to enhance the tensile strength and toughness and improve the fatigue resistance. The polypropylene fiber is selected to have a length of 12-19 mm, so as to improve the crack resistance and bridge the cracks.

5. The method for preparing C140 high-strength concrete according to claim 1, characterized in that: The following steps are involved: S1. Turn on the mixer. Before pouring the materials in, check whether the inside of the mixer is clean and whether there are any residual concrete lumps or debris. If there are any, clean them up to avoid affecting the quality of this mixing. Then, slowly pour the well-proportioned cement, silica fume, ground slag powder, and nano-silicon dioxide into the mixer in sequence, start the low-speed mixing mode, control the speed at 15-20r / min, and dry mix for 2 to 3 minutes. The operator needs to pay attention to the mixing situation at all times. The tumbling state of the powdered materials can be checked through the observation hole to ensure that they are fully mixed and evenly mixed to avoid dry powder accumulation or unevenly mixed corners. If dry powder agglomerates, the mixing time should be appropriately extended by 30 to 60 seconds until the dry powder is completely dispersed and the color is uniform. S2. After the dry mixing operation in step s1 is completed, the coarse and fine aggregates that have been cleaned in advance and dried or drained are added to the mixer. When adding, they should be poured slowly and evenly from the feed port to prevent the mixer load from increasing instantly or local material accumulation due to the concentrated dumping of aggregates. After all the aggregates are added, the mixer speed is adjusted to 20-25r / min, and the dry mixing is continued for 2 minutes. During this process, pay attention to the rolling of the aggregates in the mixer. You should see that the surface of the aggregates is gradually covered with a uniform layer of powder. If it is found that the powder on the surface of some aggregates is unevenly attached, the mixing can be appropriately suspended, and a shovel is used to manually turn it over, and then the mixing is continued to ensure that each aggregate is fully coated. S3. Slowly and evenly sprinkle the pre-dispersed steel fiber, carbon fiber and polypropylene fiber into the mixer. The sprinkling speed should be moderate, neither too fast to cause the fibers to pile up into clumps, nor too slow to affect the mixing efficiency. After all the fibers are sprinkled in, adjust the mixer speed to 20-25r / min and dry mix for 1 to 2 minutes. S4. Slowly add the pre-mixed epoxy resin emulsion, acrylic emulsion and diluted silane coupling agent mixture into the mixer. When adding, the mixture can be evenly and continuously injected into the mixer according to the established flow rate through a graduated separatory funnel or a metering pump. At the same time, turn on the mixer and increase the speed to 25-30r / min. During the stirring process of 3 to 5 minutes, the emulsion will gradually wrap around the surface of the powder and aggregate. At this time, the color of the concrete will gradually become more moist and begin to show better adhesion. If the emulsion is found to be unevenly wrapped and dry powder is exposed, the stirring time can be appropriately extended by 1 to 2 minutes to ensure that the materials are mixed evenly. S5. Pour the dissolved sodium sulfate early strength agent solution and sodium gluconate retarder solution into the mixer. Pour slowly and evenly to avoid the solution flowing into one place and causing excessive concentration of local admixtures. After all the solutions are poured in, continue stirring for 1 to 2 minutes to evenly distribute the admixtures. The effect of the admixtures can be preliminarily judged by detecting the temperature change of the mixed material. If the temperature rise or fall rate is abnormal, check whether the amount and dissolution of the admixtures are correct. Keep the mixer speed at 25-30r / min. S6. Finally, add the water reducer and the remaining water. The amount of water added is fine-tuned according to the pre-estimated workability of the concrete. First, add 80% to 90% of the estimated water, start the mixer, and stir for 5 to 8 minutes. Initially, the speed can be controlled at 25-30r / min. As the mixture gradually becomes uniform, the speed can be increased to 30-35r / min as needed, until the concrete achieves uniform and good workability without obvious segregation or water seepage.