Method for controlling surface bubbles of cast-in-place concrete structure of aluminum formwork system

Abstract

The invention discloses an aluminum mold system cast-in-place concrete structure surface bubble control method, and relates to an aluminum mold system template concrete demolding method, which comprises the following steps of: A, cleaning the surface of a template; b, according to the demolding direction, the template is divided into a front half section and a rear half section according to the ratio of 1: 2-1: 3; c, the surface of the front half section and the surface of the rear half section of the template are evenly coated with an oily release agent and a water-based release agent through a brush tool or a sprayer tool; d, waiting for the oily release agent and the water-based release agent to be completely dried; e, after the release agent is completely dried, concrete pouring is conducted, and vibration is conducted once every 1.5 m of concrete is poured till all concrete is poured; and F, after the concrete is solidified, the formwork is removed from the front half section. Compared with the prior art, the number of bubbles on the surface of the cast-in-place concrete structure is reduced and the quality of the surface of the structure is improved by optimizing the aluminum mold design, the concrete mix proportion and the construction technology.

Description

Technical Field

[0001] The invention relates to a method for demoulding concrete of an aluminum formwork system. Background Art

[0002] In China, with the rapid development of the construction industry, the application of cast-in-place concrete structures with aluminum formwork systems is becoming more and more widespread. However, during the construction process, the problem of bubbles on the concrete surface has always troubled the construction party. The problem of bubbles on the concrete surface is caused by the combined effect of multiple factors. The following are some of the main reasons for bubbles on the concrete surface: Cement type and chemical composition: Grinding aids may be added during cement production. These grinding aids contain surfactants that introduce air and produce bubbles. The fineness and alkali content of cement also affect the formation of bubbles. The finer the cement, the larger the specific surface area, the more violent the reaction with water, and the more gas may be released. The chemical composition of cement, such as too high alkali content, will react with other ingredients in concrete to produce additional gas.

[0003] Aggregate: Unreasonable gradation of aggregate, such as too much coarse aggregate, too little fine aggregate, or improper selection of aggregate particle size, will lead to loose internal structure of concrete and formation of bubbles. The water content and shape of aggregate will also affect the formation of bubbles. Aggregates with high water content will cause fluctuations in concrete slump. Aggregates with irregular shapes, such as flaky gravel, have large surface areas and are prone to produce bubbles during vibration.

[0004] Admixtures: Different types of admixtures have a significant effect on the generation of bubbles in concrete. For example, rosin-based air-entraining agents will produce more bubbles. The amount and quality of admixtures will also affect the number and size of bubbles. Excessive use of admixtures will increase the viscosity of concrete and affect the discharge of bubbles.

[0005] Water consumption and water-cement ratio: Concrete with a larger water consumption and a higher water-cement ratio is prone to air bubbles as the excess water forms blisters.

[0006] Mixing and transportation: Unreasonable mixing time will lead to uneven mixing of concrete, thus affecting the distribution and density of bubbles. Mechanical action during mixing and transportation may also introduce bubbles.

[0007] Release agent: Improper selection and use of release agent will cause bubbles on the concrete surface. Some release agents have strong adsorption to bubbles and will prevent the discharge of bubbles.

[0008] Vibration: Insufficient, uneven or improper vibration time will result in the inability to completely expel bubbles. Especially when the thickness of the concrete layer is too large, it is more difficult to expel bubbles. The speed of vibrator insertion and removal, vibration time and vibration method will affect the generation and expulsion of bubbles.

[0009] Template: The material, finish and cleanliness of the template will also affect the generation of bubbles. Smooth template surfaces produce fewer bubbles, while rough template surfaces are prone to bubbles.

[0010] Ambient temperature and humidity: When constructing in a low temperature environment, the water in the concrete evaporates more slowly, which may make it difficult for bubbles to be discharged.

[0011] Concrete mix ratio: An unreasonable mix ratio will lead to unstable concrete performance, which in turn affects the generation and discharge of bubbles.

[0012] Existing aluminum mold system template release agents are mainly divided into oily release agents and water-based release agents. Oily release agents have excellent demoulding effects, especially in complex molds, but oily release agents use oil substances as solvents, have high viscosity and low fluidity, that is, if bubbles are generated, the bubble fluidity is poor. The demoulding effect of water-based release agents is slightly inferior to that of oily release agents, but it is more suitable in environments with high environmental protection requirements. However, water-based release agents use water as solvent, have low viscosity and good fluidity, that is, the bubble fluidity is good. Summary of the invention

[0013] In view of the deficiencies in the prior art, the present invention provides a method for controlling bubbles on the surface of a cast-in-place concrete structure of an aluminum formwork system. In order to solve the above technical problems, the present invention is solved by the following technical solutions: A method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system, comprising the following steps: Step A: Clean the surface of the formwork, remove dust and debris, ensure that the surface of the formwork is clean and free of dirt, and then check whether the formwork is damaged or uneven, and if so, repair the formwork; Step B: According to the demolding direction, divide the formwork into the front half and the back half in a ratio of 1:2 to 1:3, and the first demolding part is the front half; Step C: Use a brush tool or a sprayer tool to evenly apply an oily release agent on the surface of the front half of the formwork, and use a brush tool or a sprayer tool to evenly apply a water-based release agent on the surface of the back half of the formwork, and the thickness of the oily release agent and the water-based release agent is consistent; Step D: Wait for the oily release agent and the water-based release agent to dry completely; Step E: After the release agent is completely dry, pour the concrete, and vibrate the concrete every 1.5m until all the pouring is completed; Step F: After the concrete solidifies, remove the formwork from the front half.

[0014] In the above technical scheme, preferably, in step C, when the oily release agent is applied to the dividing part between the front half and the rear half, the oily release agent can be applied to the rear half close to the dividing part, which is the transition section, and then a waterproofing agent is applied on the oily release agent in the transition section, and then a water-based release agent is applied on the waterproofing agent, and the coating thickness of the transition section is consistent with that of the front half and the rear half.

[0015] In the above technical solution, preferably, the length of the transition section does not exceed 10 cm.

[0016] In the above technical solution, preferably, in the transition section, the waterproofing agent is applied after the oily release agent is completely dried, and the water-based release agent is applied after the waterproofing agent is completely dried.

[0017] In the above technical solution, preferably, in step B, the total height of the template does not exceed 15m.

[0018] In the above technical solution, preferably, in step E, the ratio of cement, water, sand and stone in one cubic meter of concrete is 365kg-375kg: 165kg-175kg: 635kg-645kg: 1200kg-1220kg.

[0019] In the above technical solution, preferably, in step E, during vibrating, several vibrators are vertically inserted into the concrete. When the vibrators are inserted into the concrete for the first time, the insertion depth of the vibrators is not less than 100 cm. When the vibrators are not inserted into the concrete for the first time, the insertion depth of the vibrators into the lower layer of concrete is not less than 20 cm. The time for each insertion and vibration is 35s-45s.

[0020] In the above technical solution, preferably, in step A, the template joints are sealed on the outside of the template by a detachable adhesive strip.

[0021] In the above technical solution, preferably, in step A, the single-piece template is integrated from top to bottom.

[0022] In the above technical solution, preferably, when opening the mold, the mold can be opened from top to bottom or from bottom to top.

[0023] The core technical feature of this application is the mixed use of oily release agents and water-based release agents. At present, concrete demoulding mainly uses oily release agents or water-based release agents alone, but these two have their own defects. In the pouring of large concrete pieces, these two have their own defects. For example, if the oily release agent has low fluidity, when the concrete is poured at a high level, the bubbles at the bottom edge are not easy to escape, which will cause empty bags on the concrete surface. Water-based release agents are prone to residue in large-scale buildings, and the demoulding effect is poor. This application combines the advantages of oily release agents and water-based release agents for segmented coating, that is, the template is divided into the front half and the back half. The total length of the back half is much longer than the front half. The front half uses an oily release agent, and the back half uses a water-based release agent. When opening the mold, the mold is opened from the front half and extends to the back half. When opening the mold, the mold can be opened from top to bottom, and it can also be opened from the bottom up. The advantage of this setting is that since the area of ​​water-based release agent coating is larger than that of oil-based release agent coating, bubbles at the edge of the template can still escape relatively easily. When opening the mold, the mold is opened from the front half of the oil-based release agent coating. The initial stage of mold opening is very smooth, and then the back half can be directly removed from the concrete after using the force from the front half, leaving less concrete residue. Not only that, this application also increases the cement ratio in the concrete and changes the vibration parameters. When using a single-sided single-piece template, the technical effect of this application is excellent, with less bubble residue.

[0024] The present application optimizes the design of the aluminum mold, adopts a single side panel, reduces joints and gaps, improves the sealing and stability of the aluminum mold, and thus reduces the generation of bubbles. The present application optimizes the concrete mix ratio, adjusts the concrete mix ratio, optimizes the aggregate grading, increases the cement dosage, adjusts the water-cement ratio and other measures to reduce the generation of bubbles. The present application improves the construction process, adopts a mixture of oily release agents and water-based release agents, increases the flow of bubbles without greatly reducing the demoulding effect, and thus allows the bubbles to be quickly discharged. The present application improves the vibration process, such as adopting appropriate vibration methods, controlling the construction temperature, and strengthening maintenance and other measures to reduce the generation of bubbles.

[0025] The technical effects of this application include: Bubble quantity control, by optimizing the design and construction process, the number of bubbles on the surface of the structure is controlled within a certain range to ensure the appearance quality and overall performance of the structure. Bubble size control, by adjusting the concrete mix ratio and construction process, the size of the bubbles is controlled within a certain range to avoid bubbles that are too large or too small to ensure the strength and durability of the structure. Bubble distribution optimization, by reasonably designing the template and construction process, the distribution of bubbles on the surface of the structure is optimized to avoid concentrated or large-area bubbles, so as to improve the uniformity and overall performance of the structure.

[0026] By optimizing the design and construction process, the generation of bubbles can be reduced, and the treatment and maintenance costs of the concrete structure surface can be reduced, thereby reducing the project cost. By adopting advanced detection technology and optimizing the construction process, the efficiency of bubble detection and treatment can be improved, the construction period can be shortened, and the efficiency of project construction can be improved. By optimizing the design and construction process, the quality of the concrete structure surface can be improved, and the service life of the structure can be extended, thereby increasing the economic benefits of the project.

[0027] Through the research on bubble control technology of cast-in-place concrete structure with aluminum formwork system, the quality of concrete structure surface can be improved, the safety and stability of the project can be ensured, and higher quality construction products can be provided to the society. The research and application of this technology will promote the technological progress and innovative development of the construction industry and improve the overall technical level of the industry. The research and application of technology will reduce the number and size of bubbles on the surface of concrete structures, reduce pollution and damage to the environment, and enhance the environmental awareness of the society. DETAILED DESCRIPTION

[0028] Embodiment 1: A method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system, comprising the following steps: Step A: The formwork is a single-sided single-piece formwork, and the single piece is 15 meters high. First, clean the surface of the formwork, remove dust and debris, and ensure that the surface of the formwork is clean and free of dirt, and then check whether the formwork is damaged or uneven. If so, repair the formwork, which can be repaired by sheet metal repair or filling with soil, to minimize the gaps and protrusions in the formwork; after the formwork is checked, assemble it, and after assembly, seal the formwork joints on the outside of the formwork with detachable adhesive strips.

[0029] Step B: Determine the demoulding direction to be from top to bottom. Divide the template into the front half and the back half at a ratio of 5 meters:10 meters, with the front half on the upper side of the back half.

[0030] Step C: Use a brush or sprayer to evenly apply the oily release agent to the inner surface of the front half of the template. The oily release agent can be applied to the back half near the separation of the front and back halves. This is the transition section, and the length of the transition section does not exceed 10 cm. In the transition section, apply the waterproofing agent after the oily release agent is completely dry. Apply the water-based release agent after the waterproofing agent is completely dry, and apply the back half at the same time. Step D: Wait for the oily release agent and the water-based release agent to dry completely.

[0031] The water-based release agent is the aluminum mold release agent-2315N produced by Quanzhou Aosile Industrial Materials Co., Ltd., and the oil-based release agent is the concrete release agent produced by Sichuan Kelirun New Materials Technology Co., Ltd.

[0032] Step E: After the release agent is completely dry, concrete is poured. The concrete is vibrated once every 1.5m until all the concrete is poured. During pouring, the ratio of cement, water, sand and stone in one cubic meter of concrete is 375kg:165kg:635kg:1200kg. During vibration, several vibrators are vertically inserted into the concrete. When inserted into the concrete for the first time, the vibrator is inserted into the concrete to a depth of 100cm. When not inserted into the concrete for the first time, the vibrator is inserted into the lower concrete to a depth of 20cm. The time for each insertion and vibration is 45s, and the vibration frequency is 8000 times / min. The actual stop of vibration is when the concrete no longer sinks significantly, no bubbles appear, and the slurry begins to overflow. If necessary, secondary vibration is carried out. The secondary vibration is to re-vibrate the concrete at an appropriate time after the concrete is poured to improve the density and strength of the concrete. The secondary vibration time should be carried out 1-4 hours before the initial setting of the concrete, especially 1 hour before the initial setting, the effect is best. When the vibrator is inserted into the concrete for the first time during the secondary vibration, the insertion depth is 100 cm. When it is not inserted into the concrete for the first time, the vibrator is inserted into the lower layer of concrete to a depth of 20 cm. The time for each insertion and vibration is 30 seconds, and the vibration frequency is 4000 times / minute.

[0033] Step F: After the concrete solidifies, remove the formwork from the front half. When removing the formwork, first remove the removable rubber strip, then release the single-side formwork from its two side formworks, then open the front half of the formwork horizontally, and then open the formwork horizontally again. Remove the other formworks according to the above steps and clean them.

[0034] Embodiment 2: A method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system, comprising the following steps: Step A: The formwork is a single-sided single-piece formwork, and the single piece is 10 meters high. First, clean the surface of the formwork, remove dust and debris, and ensure that the surface of the formwork is clean and free of dirt, and then check whether the formwork is damaged or uneven. If so, repair the formwork, which can be repaired by sheet metal repair or filling with soil, to minimize the gaps and protrusions in the formwork; after the formwork is checked, assemble it, and after assembly, seal the formwork joints on the outside of the formwork with detachable adhesive strips.

[0035] Step B: Determine the demoulding direction to be from top to bottom. Divide the template into the front half and the back half in a ratio of 2.5 meters:7.5 meters, with the front half on the upper side of the back half.

[0036] Step C: Use a brush or sprayer to evenly apply the oily release agent to the inner surface of the front half of the template. The oily release agent can be applied to the back half near the separation of the front and back halves. This is the transition section, and the length of the transition section does not exceed 10 cm. In the transition section, apply the waterproofing agent after the oily release agent is completely dry. Apply the water-based release agent after the waterproofing agent is completely dry, and apply the back half at the same time. Step D: Wait for the oily release agent and the water-based release agent to dry completely.

[0037] The water-based release agent is the aluminum mold release agent-2315N produced by Quanzhou Aosile Industrial Materials Co., Ltd., and the oil-based release agent is the concrete release agent produced by Sichuan Kelirun New Materials Technology Co., Ltd.

[0038] Step E: After the release agent is completely dry, concrete is poured. The concrete is vibrated once every 1.5m until all the concrete is poured. During pouring, the ratio of cement, water, sand and stone in one cubic meter of concrete is 370kg:160kg:640kg:1210kg. During vibration, several vibrators are vertically inserted into the concrete. When inserted into the concrete for the first time, the vibrator is inserted into the concrete to a depth of 100cm. When it is not inserted into the concrete for the first time, the vibrator is inserted into the lower concrete to a depth of 20cm. The time for each insertion and vibration is 45s, and the vibration frequency is 8000 times / min. The actual stop of vibration is when the concrete no longer sinks significantly, no bubbles appear, and the slurry begins to overflow. If necessary, secondary vibration is carried out. The secondary vibration is to re-vibrate the concrete at an appropriate time after the concrete is poured to improve the density and strength of the concrete. The secondary vibration time should be carried out 1-4 hours before the initial setting of the concrete, especially 1 hour before the initial setting, the effect is best. When the vibrator is inserted into the concrete for the first time during the secondary vibration, the insertion depth is 100 cm. When it is not inserted into the concrete for the first time, the vibrator is inserted into the lower layer of concrete to a depth of 20 cm. The time for each insertion and vibration is 30 seconds, and the vibration frequency is 4000 times / minute.

[0039] Step F: After the concrete solidifies, remove the formwork from the front half. When removing the formwork, first remove the removable rubber strip, then release the single-side formwork from its two side formworks, then open the front half of the formwork horizontally, and then open the formwork horizontally again. Remove the other formworks according to the above steps and clean them. Embodiment 3: A method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system, comprising the following steps: Step A: The formwork is a single-sided single-piece formwork, and the single piece is 15 meters high. First, clean the surface of the formwork, remove dust and debris, and ensure that the surface of the formwork is clean and free of dirt, and then check whether the formwork is damaged or uneven. If so, repair the formwork, which can be repaired by sheet metal repair or filling with soil, to minimize the gaps and protrusions in the formwork; after the formwork is checked, assemble it, and after assembly, seal the formwork joints on the outside of the formwork with detachable adhesive strips.

[0040] Step B: Determine the demoulding direction to be from bottom to top. Divide the template into the front half and the back half at a ratio of 5 meters:10 meters, with the front half below the back half.

[0041] Step C: Use a brush or sprayer to evenly apply the oily release agent to the inner surface of the front half of the template. The oily release agent can be applied to the back half near the separation of the front and back halves. This is the transition section, and the length of the transition section does not exceed 10 cm. In the transition section, apply the waterproofing agent after the oily release agent is completely dry. Apply the water-based release agent after the waterproofing agent is completely dry, and apply the back half at the same time. Step D: Wait for the oily release agent and the water-based release agent to dry completely.

[0042] The water-based release agent is the aluminum mold release agent-2315N produced by Quanzhou Aosile Industrial Materials Co., Ltd., and the oil-based release agent is the concrete release agent produced by Sichuan Kelirun New Materials Technology Co., Ltd.

[0043] Step E: After the release agent is completely dry, concrete is poured. The concrete is vibrated once every 1.5m until all the concrete is poured. During pouring, the ratio of cement, water, sand and stone in one cubic meter of concrete is 370kg:165kg:640kg:1200kg. During vibration, several vibrators are vertically inserted into the concrete. When inserted into the concrete for the first time, the vibrator is inserted into the concrete to a depth of 100cm. When it is not inserted into the concrete for the first time, the vibrator is inserted into the lower concrete to a depth of 20cm. The time for each insertion and vibration is 45s, and the vibration frequency is 8000 times / min. The actual stop of vibration is when the concrete no longer sinks significantly, no bubbles appear, and the slurry begins to overflow. If necessary, secondary vibration is carried out. The secondary vibration is to re-vibrate the concrete at an appropriate time after the concrete is poured to improve the density and strength of the concrete. The secondary vibration time should be carried out 1-4 hours before the initial setting of the concrete, especially 1 hour before the initial setting, the effect is best. When the vibrator is inserted into the concrete for the first time during the secondary vibration, the insertion depth is 100 cm. When it is not inserted into the concrete for the first time, the vibrator is inserted into the lower layer of concrete to a depth of 20 cm. The time for each insertion and vibration is 30 seconds, and the vibration frequency is 4000 times / minute.

[0044] Step F: After the concrete solidifies, remove the formwork from the front half. When removing the formwork, first remove the removable rubber strip, then release the single-side formwork from its two side formworks, then open the front half of the formwork horizontally, and then open the formwork horizontally again. Remove the other formworks according to the above steps and clean them.

Claims

1. A method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system, characterized by: It includes the following steps: Step A: Clean the template surface, remove dust and debris, ensure that the template surface is clean and free of dirt, and then check whether the template is damaged or uneven. If so, repair the template; Step B: According to the demoulding direction, the template is divided into the front half and the back half in a ratio of 1:2 to 1:3, and the first demoulding part is the front half; Step C: Use a brush or a sprayer to evenly apply the oily release agent to the surface of the front half of the template, and use a brush or a sprayer to evenly apply the water-based release agent to the surface of the back half of the template. The thickness of the oily release agent and the water-based release agent is the same. Step D: Wait for the oily release agent and the water-based release agent to dry completely; Step E: After the release agent is completely dry, pour the concrete, and vibrate the concrete every 1.5m until the pouring is completed; Step F: After the concrete has set, remove the formwork starting from the first half.

2. The method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system according to claim 1, characterized in that In step C, when the oily release agent is applied to the dividing part between the front half and the back half, the oily release agent can be applied to the back half close to the dividing part, which is the transition section, and then a waterproofing agent is applied on the oily release agent in the transition section, and then a water-based release agent is applied on the waterproofing agent. The coating thickness of the transition section is consistent with that of the front half and the back half.

3. The method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system according to claim 2, characterized in that: The length of the transition section shall not exceed 10 cm.

4. The method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system according to claim 2, characterized in that: In the transition section, apply the waterproofing agent after the oily release agent is completely dry, and apply the water-based release agent after the waterproofing agent is completely dry.

5. The method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system according to claim 1 is characterized by: In step B, the total height of the formwork does not exceed 15m.

6. The method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system according to claim 1, characterized in that In step E, the proportions of cement, water, sand and stone in one cubic meter of concrete are 365kg-375kg: 165kg-175kg: 635kg-645kg: 1200kg-1220kg.

7. The method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system according to claim 1, characterized in that In step E, during vibration, several vibrators are vertically inserted into the concrete. When the vibrators are inserted into the concrete for the first time, the insertion depth of the vibrators is not less than 100 cm. When the vibrators are not inserted into the concrete for the first time, the insertion depth of the vibrators into the lower layer of concrete is not less than 20 cm. The time for each insertion and vibration is 35s-45s.

8. The method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system according to claim 1 is characterized by: In step A, the template seams are sealed with removable adhesive strips on the outside of the template.

9. The method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system according to claim 1, characterized in that: In step A, the single-piece template is integrated from top to bottom.

10. The method for controlling bubbles on the surface of cast-in-place concrete structure of aluminum formwork system according to claim 9, characterized in that: When opening the mold, the mold can be opened from top to bottom or from bottom to top.