Method for repairing the outer surface of a concrete precast element

Abstract

The application discloses a concrete prefabricated component outer surface repairing method, which comprises the following steps: cleaning the area to be repaired, using an electric drill to drill off the concrete of the loose repairing area to achieve the effect of chiseling, evaluating the repairing part, analyzing the stress state of the repairing part, color identification, under the action of a color difference meter and a trolley-mounted LED lamp, carrying out multi-point sampling measurement, when the repairing area is less than 1d㎡, sampling no less than 3 points, when the repairing area is greater than 1d㎡, sampling no less than 5 points, the color difference meter is close to the concrete surface during measurement, the average value is obtained, the average CIE Lab value is output by the color difference meter, and the interface of the repairing area is subjected to enhancement treatment. In the application, the concrete prefabricated component repairing method is suitable for repairing the damage of fair-faced concrete prefabricated components such as prefabricated track plates and tunnel segments, and can solve the problems of corner missing, corner chipping, collision damage and the like of the prefabricated components at low cost and high quality.

Description

Technical Field

[0001] This invention relates to the field of precast concrete component repair technology, and more particularly to a method for repairing the outer surface of precast concrete components. Background Technology

[0002] Precast concrete components are building components made of concrete and produced in factories through standardized processes. They include structural load-bearing components such as beams, slabs, columns, and shear walls, as well as municipal landscape components such as stairs and pipe corridors. Their production adopts processes such as fixed pedestal method and formwork method. Through standardized processes such as formwork cleaning, mold assembly, and concrete pouring, millimeter-level precision control is achieved. This technology can shorten the construction period by more than 50% and reduce on-site construction waste by 80%.

[0003] Currently, prefabricated components are widely used in the construction engineering field. However, during transportation and hoisting, these components are prone to appearance defects due to improper protection. Existing repair materials and processes suffer from problems such as poor compatibility, insufficient bonding strength, color differences, uneven repairs, incomplete filling, and inaccurate repair areas. Therefore, a repair method for the outer surface of prefabricated concrete components is proposed. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method for repairing the outer surface of precast concrete components. This method addresses the need for standardized repair of damaged areas in precast components, thereby avoiding color differences, improving repair efficiency and quality, saving labor costs, and facilitating quality control of precast concrete components by supervisors.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for repairing the outer surface of precast concrete components, the method comprising: S1: Clean the area to be repaired, use an electric drill to remove loose concrete in the repair area to achieve a roughening effect, assess the repair area, and analyze the stress state of the repair area. S2: Color recognition. Multi-point sampling measurement is performed under the action of colorimeter and the LED light on the trolley. When the repair area is less than 1 d㎡, the sampling is no less than 3 points, and when it is greater than 1 d㎡, the sampling is no less than 5 points. During the measurement, the colorimeter is in close contact with the concrete surface, the average value is taken, and the average CIE Lab value is output through the colorimeter. S3: Enhance the interface of the repaired area; S4: Prepare repair materials. Use an intelligent color matching system to determine the repair material formula. Utilize the average CIE Lab value measured in S2 to accurately match the closest historical data in the color-formula database of the system. Calculate the color difference ΔE = √(ΔL² + Δa² + Δb²), where L is the brightness, a is the red-green index, b is the yellow-blue index, and ΔL, Δa, and Δb are the differences between the measured value and the closest historical data value. When ΔE is less than 0.1, it is considered to have no color difference. The corresponding formula based on the same batch of reference cement for the precast component is directly obtained from historical data. The formula is determined by adjusting the amount of reference cement, standard sand, oxide raw materials or mineral admixtures, and a small sample is made. When the measured average CIE Lab value still has a calculated color difference ΔE greater than 0.1 compared to the closest historical data in the database, the formula is adjusted and a small sample is made based on this historical data. The adjustment logic is as follows: for every 2.5 increase in brightness L, the amount of white cement added increases by 10%, and the yellow-blue index b decreases by 1; when the red-green index a needs to be increased by 1.5, the amount of iron oxide red pigment is increased by 0.1%; when the yellow-blue index b needs to be increased by 2, the amount of iron oxide yellow pigment is decreased by 0.15%; the pigment ratio is adjusted according to the above logic to make a small sample. After 72 hours of standard curing, the average CIE Lab value of the sample was found to be consistent with that of the original concrete. The automatic batching machine was controlled to accurately add the corresponding amount of raw materials to the preparation tank according to the proportion to prepare cement mortar. The mixing head was replaced with an electric drill to mix evenly, reducing the error of manual operation and achieving a high degree of consistency between the color of the repair material and the color of the precast component, thereby improving the repair efficiency and effect. S5: Damage repair. The prepared cement mortar is evenly filled into the damaged area. After filling, the mortar is sealed with a plastic template or edge template. The plastic template is fixed to the surface of the component by suction cups. After the plastic template is installed, it is vibrated and smoothed to ensure that the repaired surface is uniform and consistent with the component. S6: Curing and color acceptance. After demolding, water curing is carried out for 7 days to ensure that the mortar in the repair area has fully reacted and formed strength, and its color is similar to that of the original component. Two points are taken on the original concrete of the component and two points are taken on the repair area using a colorimeter. When the average deviation of the CIE Lab value is not greater than 0.2, it is considered that the color acceptance has passed. If the color acceptance fails, it is repaired by brushing a small sample of color paste until the color acceptance is passed.

[0006] Preferably, the method for enhancing the interface of the repair area in step S3 is to spray nano-silica penetrating liquid onto the repair area, which penetrates into the pores of the concrete base layer through capillary action, reacts with free calcium to generate CSH gel, forms a rough and activated surface, and enhances the adhesion of subsequent materials.

[0007] Preferably, for repair areas larger than 1 dm² in step S2, reinforcement treatment is also required. Specifically, several fixing points are selected around the surface, acrylic structural adhesive is applied to the fixing points, and the steel wire mesh or carbon fiber mesh is fixed and covered with the acrylic structural adhesive as a reinforcement material.

[0008] Preferably, a repair cart body is provided on one side of the colorimeter, the colorimeter is placed on the repair cart body, a bracket is installed on one side of the repair cart body, a metal rod is fixedly installed on one side of the bracket, a ball joint is provided at the end of the metal rod, an LED light is installed on the ball joint, a battery, a storage box and a vehicle-mounted electric drill box are provided on the repair cart body, a vehicle-mounted electric drill is installed in the vehicle-mounted electric drill box, and casters are provided at the bottom of the repair cart body.

[0009] Preferably, the repair trolley body is equipped with a control panel and an intelligent color matching controller, the intelligent color matching controller realizing the color matching control of the intelligent color matching system.

[0010] Preferably, an automatic batching machine is provided on the top of the main body of the repair trolley, and a batching pipe is connected to the automatic batching machine.

[0011] Preferably, a preparation tank is provided on the top of the main body of the repair trolley, and the material dispensing pipe is located above the preparation tank.

[0012] Compared with the prior art, the beneficial effects of the present invention are: 1. The present invention provides a method for repairing precast concrete components, which is applicable to the repair of damaged fair-faced concrete precast components such as precast track slabs and tunnel segments. It solves the problems of chipped edges, corners, and damage to precast components at low cost and with high quality. However, the mix ratio of the repair concrete used in this method may differ from that of the original concrete, resulting in inconsistent strength. Therefore, it is not suitable for repairing components with severe damage in the main stress areas.

[0013] 2. In this invention, the method for repairing precast concrete components solves the problems of obvious color difference, low quality, and easy cracking and peeling after repair with ordinary mortar by using standard cement mortar preparation.

[0014] 3. The present invention provides a method for repairing precast concrete components, which improves the efficiency and quality of repair work and saves labor costs. Attached Figure Description

[0015] Figure 1 This is a three-dimensional structural diagram of the left side of the repair vehicle body of the present invention; Figure 2 This is a three-dimensional structural diagram of the right side of the repair vehicle body of the present invention; Figure 3 This is a cross-sectional structural schematic diagram of the present invention; Figure 4 This is a three-dimensional structural diagram of the adhesive template of the present invention viewed from the left side; Figure 5 This is a three-dimensional structural schematic diagram of the adhesive template of the present invention viewed from the right side; Figure 6 This is a three-dimensional structural diagram illustrating another application of the suction cup of the present invention.

[0016] In the diagram: 1. Repair cart body; 2. Battery; 3. Storage box; 4. Onboard electric drill box; 5. Control panel; 6. Intelligent color matching controller; 7. Casters; 8. LED lights; 9. Colorimeter; 10. Automatic batching machine; 11. Batching pipe; 12. Preparation tank; 13. Plastic template; 14. Template interior; 15. Wavy texture; 16. Template exterior; 17. Suction cup; 18. Handle; 19. Card holder; 20. Metal rod; 21. Ball joint; 22. Template fixing strap. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] In the description of this patent, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this patent based on the specific circumstances.

[0019] Example: Refer to Figure 1-6 A method for repairing the outer surface of a precast concrete component, the method comprising: S1: Clean the area to be repaired, use an electric drill to remove loose concrete in the repair area to achieve a roughening effect, assess the repair area, and analyze the stress state of the repair area. S2: Color recognition. Multi-point sampling measurement is performed under the action of colorimeter 9 and the LED light 8 on the trolley. When the repair area is less than 1 d㎡, the sampling is no less than 3 points, and when it is greater than 1 d㎡, the sampling is no less than 5 points. During the measurement, colorimeter 9 is in close contact with the concrete surface, and the average value is taken. The average CIE Lab value is output through colorimeter 9. S3: Enhance the interface of the repaired area; S4: Prepare repair materials. An intelligent color matching system determines the repair material formula. Using the average CIE Lab value measured in S2, it precisely matches the closest historical data in the system's color-formula database and calculates the color difference. Where L is the brightness, a is the red-green index, b is the yellow-blue index, and ΔL, Δa, and Δb are the differences between the measured value and the closest historical value. When ΔE is less than 0.1, it is considered to have no color difference. The corresponding formula based on the same batch of reference cement for the precast component is directly obtained from historical data. The formula is determined by adjusting the amount of reference cement, standard sand, oxide raw materials or mineral admixtures, and a small sample is made. When the measured average CIE Lab value still has a calculated color difference ΔE greater than 0.1 compared to the closest historical data in the database, the formula is adjusted and a small sample is made based on this historical data. The adjustment logic is as follows: for every 2.5 increase in brightness L, the amount of white cement added increases by 10%, and the yellow-blue index b decreases by 1; when the red-green index a needs to be increased by 1.5, the amount of iron oxide red pigment is increased by 0.1%; when the yellow-blue index b needs to be increased by 2, the amount of iron oxide yellow pigment is decreased by 0.15%; the pigment ratio is adjusted according to the above logic to make a small sample. After 72 hours of standard curing, the average CIE Lab value of the sample was found to be consistent with that of the original concrete. The automatic batching machine was controlled to accurately add the corresponding amount of raw materials to the preparation tank according to the proportion to prepare cement mortar. The mixing head was replaced with an electric drill to mix evenly, reducing the error of manual operation and achieving a high degree of consistency between the color of the repair material and the color of the precast component, thereby improving the repair efficiency and effect. S5: Damage repair. The prepared cement mortar is evenly filled into the damaged area. After filling, the adhesive template 13 or the side template is sealed. The adhesive template 13 is fixed to the surface of the component by suction cup 17. After the adhesive template 13 is installed, it is vibrated and smoothed to ensure that the repair surface is uniform and consistent with the component. S6: Curing and color acceptance. After demolding, water curing is carried out for 7 days to ensure that the mortar in the repair area has fully reacted and formed strength, and its color is similar to that of the original component. Two points are taken on the original concrete of the component and two points are taken on the repair area using a colorimeter 9. The average deviation of the CIE Lab value is not greater than 0.2, which is considered as passing the color acceptance. If the color acceptance fails, it is repaired by brushing a small sample of color paste until the color acceptance is passed.

[0020] As a technical optimization of the present invention, the method for enhancing the interface of the repair area in step S3 is as follows: spray nano-silica penetrating liquid onto the repair area, which penetrates into the pores of the concrete base layer through capillary action, reacts with free calcium to generate CSH gel, forming a rough and activated surface, and enhancing the adhesion of subsequent materials. For repair areas larger than 1 dm² in step S2, reinforcement treatment is also required. Specifically, several fixing points are selected around the surface, acrylic structural adhesive is applied to the fixing points, and steel wire mesh or carbon fiber mesh is fixed and covered with acrylic structural adhesive as reinforcement material.

[0021] As a technical optimization of the present invention, a repair cart body 1 is provided on one side of the colorimeter 9. The colorimeter 9 is placed on the repair cart body 1 for easy portability and convenient removal for measuring concrete. A bracket 19 is installed on one side of the repair cart body 1, and a metal rod 20 is fixedly installed on one side of the bracket 19. A ball joint 21 is provided at the end of the metal rod 20. An LED light 8 is installed on the ball joint 21. The rotation range of the LED light 8 can be adjusted by rotating the ball joint 21. The repair cart body 1 is provided with a battery 2, a storage box 3, and a vehicle-mounted electric drill box 4. The vehicle-mounted electric drill box 4 is equipped with a battery 2, a storage box 3, and a drill box 4. The vehicle-mounted electric drill and repair trolley body 1 are equipped with casters 7 at the bottom. Multiple casters 7 are attached to the bottom of the repair trolley body 1, with four sets, for easy movement and adaptation to complex construction site environments. A battery 2 is located at the bottom of the repair trolley body 1, providing power to the electric drill, control panel 5, intelligent color controller 6, etc. When not in use, the electric drill is stored in the electric drill box 4. The electric drill can be used to remove loose concrete from damaged precast components, and can also be used to drill holes and insert small-diameter expansion bolts to fix wire mesh, ensuring a good connection between the repaired area and the precast component. The repair trolley body 1 is equipped with a storage box 3, which can carry standard sand, etc. Ordinary silicate cement, iron oxide red pigments, mineral admixtures, water, etc. The initial setting time of this cement is not less than 45 minutes and the final setting time is not more than 10 hours. To ensure that the bonding performance and strength of the cement mortar meet the requirements, the specific surface area of ​​this cement should be between 300-350 m² / kg.

[0022] As a technical optimization of the present invention, the repair cart body 1 is equipped with a control panel 5 and an intelligent color matching controller 6. The intelligent color matching controller 6 realizes the color matching control of the intelligent color matching system. The repair cart body 1 is equipped with an intelligent color matching controller 6 and a colorimeter 9. The intelligent color matching controller 6 controls the color matching of the intelligent color matching system. The colorimeter 9 measures the average CIE Lab value of the component from the damaged surface under the illumination of LED light 8. The repair cart body 1 has its own D65... The system includes a standard LED light source (8), and a pre-set color-formula database in the intelligent color matching system. This database contains no fewer than 50 different cement mortar color ratios and corresponding pigments (iron oxide red, iron oxide yellow, chromium oxide green, and other inorganic pigments have good weather resistance and stability and can be used for concrete repair). The cement mortar prepared according to this ratio will have a color consistent with the preset color after final setting and curing. The system automatically matches three of the closest colors and sends them to the control panel (5). The mortar color is manually selected. The main body (1) of the repair cart is equipped with an automatic batching machine (10). The automatic batching machine (10) automatically and accurately mixes the raw materials required for the cement mortar according to the selected mortar color on the control panel (5) and sends them to the mortar preparation tank (12). The general ratio is cement:sand:water:pigment = 1:2.5:0.45:0.02. The specific ratio depends on the corresponding ratio below the color swatch.

[0023] As a technical optimization of the present invention, an automatic batching machine 10 is provided on the top of the repair trolley body 1, and a batching pipe 11 is connected to the automatic batching machine 10. A preparation tank 12 is provided on the top of the repair trolley body 1, and the batching pipe 11 is located above the preparation tank 12. A stainless steel cement mortar preparation tank 12 is provided on the top of the repair trolley body 1. The worker replaces the electric drill with a double S square head mixing head and uses the electric drill to mix the cement mortar for 3 minutes. Mechanical mixing is more uniform than manual mixing, so as to ensure that the performance of the cement mortar meets the requirements. The prepared cement mortar is then evenly filled into the damaged area.

[0024] The sides are fixed using a plastic template 13. The plastic template 13 has an inner template 14 and an outer template 15 on each side. The outer template 15 has suction cups 17 made of soft plastic at both ends. Because the surface of the precast fair-faced concrete component is relatively smooth, when fixing the template, pressing down on the handles 18 of the soft plastic suction cups 17 creates a negative pressure chamber inside the suction cups 17, where the internal air pressure is lower than the external atmospheric pressure. The inner template 14 of the plastic template 13 has wavy lines 15 arranged around its perimeter to increase the coefficient of friction. According to the formulas F=pS and f=μN, the entire plastic template 13 will be fixed to the surface of the fair-faced concrete component. After fixing, the mortar is vibrated and smoothed to ensure the repaired surface is flat and consistent with other parts of the component. After the cement mortar has fully set, the plastic template 13 is removed, and the surface is covered with plastic film for curing. After 7 days of curing, the design strength and color are achieved, completing the concrete repair.

[0025] When it is inconvenient for the adhesive template 13 to be directly attached to the suction cup 17, a fixing template strap 22 is fixedly installed on the side of the adhesive template 13. The suction cup 17 is then attached to one side of the fixing template strap 22. Thus, the position of the adhesive template 13 can be moved through transmission, which is convenient for use in different environments.

[0026] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0027] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for repairing the outer surface of precast concrete components, characterized in that: The method includes: S1: Clean the area to be repaired, use an electric drill to remove loose concrete in the repair area to achieve a roughening effect, assess the repair area, and analyze the stress state of the repair area. S2: Color recognition. Multi-point sampling measurement is carried out under the action of colorimeter (9) and the LED light (8) on the car. When the repair area is less than 1 d㎡, the sampling is not less than 3 points, and when it is greater than 1 d㎡, the sampling is not less than 5 points. When measuring, the colorimeter (9) is close to the concrete surface, and the average value is taken. The average CIE Lab value is output through the colorimeter (9). S3: Enhance the interface of the repaired area; S4: Prepare repair materials. An intelligent color matching system determines the repair material formula. Using the average CIELab value measured in S2, it precisely matches the closest historical data in the system's color-formula database and calculates the color difference. Where L is the brightness, a is the red-green index, b is the yellow-blue index, and ΔL, Δa, and Δb are the differences between the measured value and the closest historical value. When ΔE is less than 0.1, it is considered to have no color difference. The corresponding formula based on the same batch of reference cement for the precast component is directly obtained from historical data. The formula is determined by adjusting the amount of reference cement, standard sand, oxide raw materials or mineral admixtures, and a small sample is made. When the measured average CIE Lab value still has a calculated color difference ΔE greater than 0.1 compared to the closest historical data in the database, the formula is adjusted and a small sample is made based on this historical data. The adjustment logic is as follows: for every 2.5 increase in brightness L, the amount of white cement added increases by 10%, and the yellow-blue index b decreases by 1; when the red-green index a needs to be increased by 1.5, the amount of iron oxide red pigment is increased by 0.1%; when the yellow-blue index b needs to be increased by 2, the amount of iron oxide yellow pigment is decreased by 0.15%; the pigment ratio is adjusted according to the above logic to make a small sample. After 72 hours of standard curing, the average CIE Lab value of the sample was found to be consistent with that of the original concrete. The automatic batching machine was controlled to accurately add the corresponding amount of raw materials to the preparation tank according to the proportion to prepare cement mortar. The mixing head was replaced with an electric drill to mix evenly, reducing the error of manual operation and achieving a high degree of consistency between the color of the repair material and the color of the precast component, thereby improving the repair efficiency and effect. S5: Damage repair, fill the damaged area evenly with the prepared cement mortar, and seal the plastic template (13) after filling. The plastic template (13) is fixed to the surface of the component by suction cup (17). After the plastic template (13) is installed, it is vibrated and smoothed to ensure that the repair surface is uniform and consistent with the component. S6: Curing and color acceptance. After demolding, water curing is carried out for 7 days to ensure that the mortar in the repaired part fully reacts and forms strength and is similar in color to the original component. A colorimeter (9) is used to take two points on the original concrete of the component and two points on the repaired part for measurement. When the average deviation of the CIE Lab value is not greater than 0.2, it is considered that the color acceptance is passed. If the color acceptance is not passed, it is repaired by brushing a small sample of color paste until the color acceptance is passed.

2. The method for repairing the outer surface of a precast concrete component according to claim 1, characterized in that, The method for enhancing the interface of the repair area described in step S3 is to spray nano-silica penetrating liquid onto the repair area, which penetrates into the pores of the concrete base layer through capillary action, reacts with free calcium to generate CSH gel, forms a rough and activated surface, and enhances the adhesion of subsequent materials.

3. The method for repairing the outer surface of a precast concrete component according to claim 1, characterized in that, For repair areas larger than 1 dm² in step S2, reinforcement treatment is required. Specifically, several fixing points are selected around the surface, acrylic structural adhesive is applied to the fixing points, and the steel wire mesh or carbon fiber mesh is fixed and covered with the acrylic structural adhesive as a reinforcement material.

4. The method for repairing the outer surface of a precast concrete component according to claim 1, characterized in that, The colorimeter (9) is provided with a repair cart body (1) on one side. The colorimeter (9) is placed on the repair cart body (1). A card holder (19) is installed on one side of the repair cart body (1). A metal rod (20) is fixedly installed on one side of the card holder (19). A ball joint (21) is provided at the end of the metal rod (20). An LED light (8) is installed on the ball joint (21). A battery (2), a storage box (3) and a vehicle-mounted electric drill box (4) are provided on the repair cart body (1). A vehicle-mounted electric drill is installed in the vehicle-mounted electric drill box (4). A caster wheel (7) is provided at the bottom of the repair cart body (1).

5. A method for repairing the outer surface of a precast concrete component according to claim 4, characterized in that, The main body (1) of the repair vehicle is equipped with a control panel (5) and an intelligent color matching controller (6), which realizes the color matching control of the intelligent color matching system.

6. A method for repairing the outer surface of a precast concrete component according to claim 5, characterized in that, An automatic batching machine (10) is provided on the top of the main body (1) of the repair trolley, and a batching pipe (11) is connected to the automatic batching machine (10).

7. A method for repairing the outer surface of a precast concrete component according to claim 6, characterized in that, The top of the repair trolley body (1) is provided with a preparation tank (12), and the feeding pipe (11) is located above the preparation tank (12).

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