Manufacturing process of high-performance concrete prefabricated part

Abstract

The invention relates to the technical field of constructional engineering, and discloses a manufacturing process of a high-performance concrete prefabricated component, which comprises the following steps: S1, raw material preparation: according to a design formula, respectively weighing required raw materials of the concrete prefabricated component; s2, mixing: putting the raw materials into a double-shaft forced stirrer for stirring to obtain concrete slurry; s3, vibration forming is conducted, specifically, the mixed concrete slurry is injected into a prefabricated part mold, bubbles are eliminated through a high-frequency vibrator, and a prefabricated part is compacted; s4, steam curing is conducted, specifically, the formed prefabricated part is put into a steam curing chamber; s5, demolding is conducted; and S6, stacking. The concrete prefabricated part is manufactured through key equipment such as the double-shaft forced mixer, the high-frequency vibrator, the steam curing chamber and the hydraulic jacking device, the quality of the prefabricated part is improved in all directions, the production efficiency is remarkably improved, the production cost is reduced, and the production of the high-performance concrete prefabricated part is more efficient.

Description

Technical Field

[0001] The present invention relates to the technical field of construction engineering, and particularly to a manufacturing process for high-performance concrete precast components. Background Art

[0002] At present, with the acceleration of the urbanization process and the growth of construction engineering demands, prestressed concrete components have been widely used in modern architecture due to their excellent mechanical properties and durability. However, there are many problems in the traditional production process of concrete precast components, such as low production efficiency, high cost, unstable quality, etc. These problems limit the further popularization and application of high-performance concrete precast components in large-scale projects.

[0003] The production cycle of the traditional wet casting process is too long to meet the time requirements of large-scale engineering projects. Secondly, although the dry preparation process improves production efficiency, the internal porosity after forming is relatively high, reducing the mechanical properties of the product. In addition, although the automated production line can significantly improve quality and efficiency, its high cost limits its popularization and application in small and medium-sized enterprises. Summary of the Invention

[0004] In view of the deficiencies of the prior art, the present invention provides a manufacturing process for high-performance concrete precast components, which solves the problems of long production cycle, difficult product quality assurance and high cost.

[0005] To achieve the above objectives, the present invention is realized through the following technical solutions: A manufacturing process for high-performance concrete precast components, comprising the following steps: S1. Raw material preparation: Weigh the raw materials required for the concrete precast components according to the design formula; S2. Mixing: Put the raw materials into a twin-shaft compulsory mixer for mixing to obtain concrete slurry; S3. Vibration forming: Inject the mixed concrete slurry into the precast component mold, and eliminate air bubbles and compact the precast components through a high-frequency vibrator; S4. Steam curing: Put the formed precast components into a steam curing chamber and cure the precast components through steam; S5. Demolding: After the precast components reach the designed strength, use a hydraulic lifting device to take out the precast components from the mold; S6. Stacking: Stack the demolded precast components in a ventilated area in a specified manner for natural curing.

[0006] Preferably, the raw materials in S1 include cement, fine aggregate, coarse aggregate and admixture.

[0007] Preferably, the capacity of the twin-shaft compulsory mixer in S2 is 5 cubic meters and the power is 75 kilowatts.

[0008] Preferably, in S3, the frequency range of the high-frequency vibrator is 60 - 80 Hz, the maximum exciting force is 10 tons, and the vibration time is 3 - 5 minutes.

[0009] Preferably, in S4, the heating rate of the steam curing chamber is 15 - 20 °C per hour, the curing time is 3 - 5 hours, the temperature control accuracy of the steam curing chamber is ±1 °C, and the humidity control range is 40% - 90% RH.

[0010] Preferably, in S5, the rated load of the hydraulic jacking device is 50 tons and the stroke is 1 meter.

[0011] Preferably, in S6, the precast components are separated by cushion woods, the thickness of the cushion woods is 20 mm, and the stacking height does not exceed 3 layers.

[0012] A high-performance concrete precast component, the concrete precast component includes P.O42.5 grade ordinary Portland cement, natural river sand fine aggregate with a particle size less than 5 mm, crushed stone coarse aggregate with a particle size of 5 - 20 mm, and polycarboxylate-based water reducer, and the water reduction rate of the polycarboxylate-based water reducer is 20% - 40%.

[0013] The present invention provides a manufacturing process for a high-performance concrete precast component. It has the following beneficial effects: 1. The present invention manufactures concrete precast components through key equipment such as a twin-shaft forced mixer, a high-frequency vibrator, a steam curing chamber, and a hydraulic jacking device, comprehensively improving the quality of the precast components, significantly increasing the production efficiency, reducing the production cost, and making the production of high-performance concrete precast components more efficient.

[0014] 2. The present invention uses a gradient heating method for steam curing, which not only accelerates the cement hydration reaction and shortens the production cycle, but also avoids defects such as cracks caused by sudden temperature rise, ensuring the structural integrity of the precast components and the steady growth of strength, improving product quality, extending service life, and reducing the later maintenance cost.

[0015] 3. The present invention uses a twin-shaft forced mixer, which can not only meet the large-scale production requirements but also ensure the stable and consistent properties of concrete slurries in different batches. The high-speed rotating twin shafts generate strong shear force and extrusion force, enabling the raw materials to be evenly mixed in a short time, accelerating the hydration reaction, and forming a uniform and stable concrete slurry. At the same time, a high-frequency vibrator is used to promote the full flow of the concrete slurry, fill the mold, reduce air bubbles and porosity, and ensure the complete shape, accurate dimensions, and high mechanical performance of the precast components. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a flow chart of a manufacturing process for a high-performance concrete precast component of the present invention. Detailed implementation mode

[0017] The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0018] Please refer to the attached Figure 1 , the embodiment of the present invention provides a manufacturing process for high-performance concrete precast components, including the following steps: S1. Raw material preparation: Weigh the raw materials required for the concrete precast components respectively according to the design formula; S2. Mixing: Put the raw materials into a twin-shaft forced mixer for mixing to obtain concrete slurry; S3. Vibration molding: Pour the mixed concrete slurry into the precast component mold, and eliminate air bubbles and compact the precast components through a high-frequency vibrator; S4. Steam curing: Put the formed precast components into a steam curing chamber and cure the precast components through steam; S5. Demolding: After the precast components reach the designed strength, use a hydraulic jacking device to take out the precast components from the mold; S6. Stacking: Stack the demolded precast components in a ventilated area in a specified manner for natural curing.

[0019] Specifically, by accurately weighing the required raw materials strictly according to the design formula in S1, the accuracy of the concrete mix ratio can be ensured, which plays a decisive role in controlling the key properties such as the strength, durability, and workability of the concrete precast components. At the same time, problems such as segregation and bleeding caused by improper material ratios can be avoided, thereby improving the construction performance of the concrete and making it easy to pour and vibrate; By putting the raw materials into a twin-shaft forced mixer for mixing in S2, with the unique twin-shaft structure and forced mixing working mode of the mixer, various raw materials can be fully and evenly mixed in a short time, achieving efficient mixing, thereby optimizing the microstructure of the concrete, improving its durability and later strength. In addition, uniform mixing can ensure that the properties of each part of the concrete are consistent, avoiding problems such as excessive local strength differences or other quality problems, and ensuring that the finally produced concrete precast components have high stability and reliability in quality, so as to meet the high standards required for precast components in various projects; The S3 uses a high-frequency vibrator to vibrate. High-frequency vibration can generate a strong force to break the friction and cohesion between the particles inside the concrete, so that the concrete slurry can flow fully in the mold and fill every corner of the mold, ensuring the complete shape and accurate size of the precast components. At the same time, it effectively reduces the residual bubbles, reduces the porosity inside the precast components, improves its density, and enhances the mechanical properties of the precast components such as compressive strength and flexural strength, so that it can withstand greater loads and meet the structural requirements of the project, providing a solid guarantee for the manufacture of high-quality and high-performance concrete precast components. The heat and humidity released by the steam curing room in S4 can create a high temperature and high humidity environment. In such an environment, the hydration reaction speed of cement is greatly accelerated, and various components in the concrete can react chemically quickly, prompting the cement stone to form quickly and continuously crystallize, thereby accelerating the hardening process of prefabricated components, enabling them to obtain higher early strength in a short time, shortening the production cycle, improving production efficiency, and meeting the progress requirements of the project. In addition, the high temperature and high humidity curing environment is conducive to the uniform distribution of moisture inside the concrete, reducing shrinkage cracks caused by moisture evaporation, and improving the structural stability of the components; S5 uses a hydraulic jacking device to perform demoulding operations, avoiding collisions, damages and other problems that may be caused by traditional manual demoulding, and ensuring the integrity and appearance quality of prefabricated components to the greatest extent. At the same time, during the demoulding process, the hydraulic jacking device can evenly apply force to the prefabricated components with its stable jacking force and precise control performance, so that the force is evenly applied to the prefabricated components during the process of leaving the mold, preventing cracks, deformation and other quality defects in the components caused by uneven force, thereby ensuring that the size accuracy and shape of the prefabricated components meet the design requirements, ensuring the quality and accuracy of the prefabricated components, and improving production efficiency; By stacking the demoulding prefabricated components in a ventilated area in a prescribed manner through S6, the prefabricated components can be naturally cured in a relatively stable and suitable environment. A well-ventilated environment is conducive to the moderate evaporation of moisture on the surface of the prefabricated components, maintaining the humidity balance inside the concrete, and continuously providing the necessary moisture conditions for the hydration reaction of cement, thereby promoting further hydration of cement, thereby continuously improving the strength and density of the prefabricated components and allowing them to meet the various performance indicators required by the design.

[0020] The raw materials in S1 include cement, fine aggregate, coarse aggregate and admixtures.

[0021] Specifically, cement, as a cementitious material, undergoes a hydration reaction when it comes into contact with water. The resulting gel can tightly bond fine aggregate and coarse aggregate together to form a solid whole, providing essential strength support for concrete and determining the basic mechanical properties of prefabricated components. Fine aggregates can effectively improve the workability of concrete, enabling the concrete to flow more smoothly during mixing, transportation, and pouring, facilitating construction operations. Coarse aggregates play a skeletal role in concrete, bearing the main load, enhancing the compressive strength and durability of concrete, and ensuring that precast components can withstand large external forces during actual use. Admixtures can significantly reduce the water consumption and lower the water-cement ratio without reducing the workability of concrete, thereby improving the strength and durability of concrete. This achieves excellent performance in multiple aspects such as strength, workability, and durability for high-performance concrete precast components, providing a fundamental guarantee for producing high-quality precast components that meet various engineering requirements.

[0022] In S2, the capacity of the twin-shaft compulsory mixer is 5 cubic meters, and the power is 75 kilowatts.

[0023] Specifically, the relatively large capacity of the twin-shaft compulsory mixer means that it can handle a large amount of raw materials at one time, meeting the needs of large-scale production, improving production efficiency, and ensuring the consistent properties of concrete slurries in different batches during batch production, avoiding quality fluctuations caused by frequent mixing of small batches of materials. Moreover, the powerful 75-kilowatt power provides strong driving force for the mixer, enabling the twin shafts to rotate at high speed and generate strong shear force and extrusion force, which can uniformly mix various materials such as cement, aggregates, and admixtures in a short time, accelerate the hydration reaction between cement and water, and enable the cement paste to fully wrap the aggregate particles, forming a uniform and stable concrete slurry.

[0024] In S3, the frequency range of the high-frequency vibrator is 60 - 80 Hz, the maximum exciting force is 10 tons, and the vibration time is 3 - 5 minutes.

[0025] Specifically, the high-frequency vibration of the high-frequency vibrator can generate powerful oscillation energy, which is quickly transmitted to the concrete slurry injected into the mold, causing the particles inside the slurry to have intense relative movement, enabling the concrete slurry to flow more smoothly in the mold and fill every fine corner of the mold, ensuring the precise shape and size of the precast component. The maximum exciting force of 10 tons provides strong power support for this vibration. Even for concrete with poor fluidity or large aggregate particle size, it can ensure sufficient vibration intensity, making the concrete slurry more dense and reducing the porosity.

[0026] In S4, the heating rate of the steam curing chamber is 15 - 20 °C per hour, the curing time is 3 - 5 hours, the temperature control accuracy of the steam curing chamber is ±1 °C, and the humidity control range is 40% - 90% RH.

[0027] Specifically, the way of gradient heating avoids the sharp change of temperature. At the initial stage of heating, the temperature is increased at a relatively gentle speed, enabling the moisture and cement components inside the precast components to gradually adapt to the temperature change, and avoiding excessive temperature stress inside the components caused by sudden temperature rise, thereby effectively preventing the generation of defects such as cracks, ensuring the structural integrity of the precast components. Moreover, as the heating process progresses, at a reasonable heating rate of 15 - 20 °C per hour, the hydration reaction of cement is gradually accelerated, providing favorable conditions for the setting and hardening of concrete. And the curing time is controlled within 3 - 5 hours, giving sufficient time for the cement to undergo hydration reaction, promoting the steady growth of the strength of concrete, meeting the strength standard required by the design, thus improving the overall quality of the precast concrete components, enabling them to play a reliable role in actual engineering applications and meeting the requirements of various complex environments and working conditions.

[0028] In S5, the rated load of the hydraulic jacking device is 50 tons and the stroke is 1 meter.

[0029] Specifically, the rated load of 50 tons of the hydraulic jacking device can easily carry and jack up large high-performance precast concrete components. Whether it is heavy components such as beams and columns, they can achieve height increase with this powerful jacking force. And the 1-meter stroke effectively guarantees the spatial transfer of the components, facilitating subsequent demoulding operations, greatly reducing the risk of damage to the precast components, thereby effectively improving the production quality and transfer efficiency of the precast components, and ensuring the efficient and orderly progress of the entire production process.

[0030] In S6, the precast components are separated by cushion woods. The thickness of the cushion woods is 20 mm and the stacking height does not exceed 3 layers.

[0031] Specifically, the cushion woods play a buffering role between the precast components, avoiding damage situations such as deformation and cracks of the components caused by excessive local pressure, ensuring the integrity and appearance quality of the precast components. Moreover, the cushion woods separate the components, making each component relatively independent, avoiding direct contact and friction between the components, preventing problems such as corner defects and surface scratches caused by collisions, ensuring that the precast components always maintain a good state during stacking. And restricting the stacking height can reduce the risk of collapse caused by unstable center of gravity, ensuring the safety of the construction site.

[0032] A kind of high-performance precast concrete component, the precast concrete component includes P.O42.5 grade ordinary portland cement, natural river sand fine aggregate with a particle size less than 5 mm, crushed stone coarse aggregate with a particle size of 5 - 20 mm, and polycarboxylate-based water reducer. The water reducing rate of the polycarboxylate-based water reducer is 20% - 40%.

[0033] Specifically, P.O42.5 ordinary Portland cement, as the core cementitious material, has good cementing ability. After contacting water, it can quickly undergo hydration reaction, and the generated gel will tightly bond fine aggregate and coarse aggregate together, providing a solid strength foundation for concrete, ensuring that precast components can withstand large external forces during actual use and meeting the strength requirements of engineering structures. Natural river sand fine aggregate with a particle size less than 5 mm has uniform particles and hard texture. It can fill the voids between coarse aggregates, effectively improving the grading of concrete, making the aggregate distribution more uniform, significantly enhancing the workability of concrete, enabling good fluidity of concrete during mixing, transportation and pouring, facilitating construction operations, and also contributing to improving the density and durability of concrete. Crushed stone coarse aggregate with a particle size of 5 - 20 mm can bear most of the loads, enhancing the compressive strength and flexural strength of concrete and ensuring the structural stability of precast components. Polycarboxylate superplasticizer is the key additive in the whole formula. Without affecting the workability of concrete, it can significantly reduce the water consumption and lower the water-cement ratio, thereby making the pore structure of concrete more dense and improving the strength and durability of concrete.

[0034] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A manufacturing process for high performance concrete prefabricated components, characterized in that: The following steps are involved: S1. Raw material preparation: weigh the raw materials of the required precast concrete components according to the design formula; S2, mixing: putting the raw materials into a double-shaft forced mixer for mixing to obtain concrete slurry; S3, vibration molding: inject the mixed concrete slurry into the precast component mold, and use a high-frequency vibrator to eliminate bubbles and make the precast component dense; S4, steam curing: placing the prefabricated components after forming into a steam curing room, and curing the prefabricated components by steam; S5, demoulding: after the prefabricated component reaches the designed strength, the prefabricated component is taken out of the mold by using a hydraulic jacking device; S6. Stacking: Stack the demoulded prefabricated components in a ventilated area in a prescribed manner for natural curing.

2. The manufacturing process of a high performance concrete prefabricated component according to claim 1, characterized in that: The raw materials in S1 include cement, fine aggregate, coarse aggregate and admixtures.

3. The manufacturing process of a high performance concrete prefabricated component according to claim 1, characterized in that: The capacity of the twin-shaft forced mixer in S2 is 5 cubic meters and the power is 75 kilowatts.

4. The manufacturing process of a high performance concrete prefabricated component according to claim 1, characterized in that: The frequency range of the S3 medium-high frequency vibrator is 60-80 Hz, the maximum exciting force is 10 tons, and the vibration time is 3-5 minutes.

5. The manufacturing process of a high performance concrete prefabricated component according to claim 1, characterized in that: The heating rate of the steam curing room in S4 is 15-20°C per hour, the curing time is 3-5 hours, the temperature control accuracy of the steam curing room is ±1°C, and the humidity control range is 40% to 90%RH.

6. The manufacturing process of a high performance concrete prefabricated component according to claim 1, characterized in that: The rated load of the hydraulic jacking device in S5 is 50 tons and the stroke is 1 meter.

7. The manufacturing process of a high performance concrete prefabricated component according to claim 1, characterized in that: The prefabricated components in S6 are separated by wooden blocks, the thickness of the wooden blocks is 20 mm, and the stacking height does not exceed 3 layers.

8. A high-performance precast concrete component, according to the manufacturing process of a high-performance precast concrete component according to any one of claims 1 to 7, characterized in that: The precast concrete components include P.O42.5 grade ordinary Portland cement, natural river sand fine aggregate with a particle size of less than 5mm, crushed stone coarse aggregate with a particle size of 5-20mm and polycarboxylic acid series water reducer, and the water reduction rate of the polycarboxylic acid series water reducer is 20% to 40%.

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