Construction method for prefabricating and assembling ultra-high performance concrete exterior trimming panel by using stand column

Abstract

The invention relates to the technical field of concrete structure manufacturing, in particular to a construction method for a prefabricated and assembled ultra-high-performance concrete exterior decoration plate by using a stand column. Each prefabricated assembled ultra-high performance concrete exterior trimming plate comprises an exterior facade part and an L-shaped part matched with the corresponding stand column, and each L-shaped part comprises an L-shaped structure capable of surrounding the corresponding stand column from two opposite directions. The outer vertical face part of the prefabricated and assembled ultra-high-performance concrete outer decoration plate is firstly poured, and the L-shaped part of the prefabricated and assembled ultra-high-performance concrete outer decoration plate is poured within a certain time, so that the ultra-high-performance concrete poured twice is fully mixed to form a whole. The method has the advantages that the whole structural form does not need a steel structure, so that the construction difficulty is greatly reduced while the cost is reduced; the hoisting weight and the hoisting construction difficulty are greatly reduced due to split prefabrication; when the decorative breast board is constructed, the purpose of repairing and reinforcing the stand column is achieved.

Description

Technical Field

[0001] This invention relates to the field of concrete structure fabrication technology, and in particular to a construction method for prefabricated and assembled ultra-high performance concrete exterior panels using columns, especially a construction method for irregularly shaped ultra-high performance concrete exterior panels and a method for reinforcing and repairing old columns. Background Technology

[0002] Ordinary fair-faced concrete exterior railings are heavy, posing significant challenges to hoisting and installation, and cannot meet the requirements of high tensile stress in certain projects. To facilitate connection, pre-embedded steel components (such as square tubes and angle brackets) are typically used to externally hang the railings. This method is complex and does not allow for the repair and reinforcement of existing old posts.

[0003] Although alloy exterior railings are lightweight, they are prone to deformation and corrosion, and their decorative effect is inferior to that of concrete. Welding and other construction methods are also unsuitable for projects with tight schedules.

[0004] Ultra-high performance concrete (UHPC) offers the possibility of creating thin-walled, irregularly shaped decorative components due to its extremely high strength and excellent fluidity. Its superior durability, hydrophobic properties, and excellent color and texture effects make it the top choice for exterior balconies renovation.

[0005] The amount of cementitious material used in UHPC generally exceeds 1000 kg / m³. 3 The hydration reaction is intense, and the plastic and chemical shrinkage is much greater than that of conventional concrete. During component casting, shrinkage cracks are easily generated, while the exterior panels have high requirements for appearance. When the guardrail panels are relatively tall, the formwork is prone to damage or deformation during the vertical casting of irregularly shaped components, which greatly increases the formwork cost, brings difficulties to the casting production, and reduces production efficiency.

[0006] The following technical problems exist when using existing technologies to manufacture prefabricated UHPC exterior panels: (1) Most of the existing construction types are external panel construction, which requires drilling holes and other damage to the existing old columns, which can easily cause structural damage to the old columns, and even instability in severe cases. (2) Outward-facing UHPC decorative panels have high aesthetic requirements, but thin-walled UHPC is prone to shrinkage cracks and micro-bubbles, which affect the finished effect of prefabricated decorative panels; (3) When the height of the precast components is relatively high, the use of wooden molds is prone to "molding bulging" defects, so the requirements for the molds are relatively high, which increases the production cost; (4) A set of procedures and methods for UHPC precast decorative panel construction and old column repair and reinforcement construction needs to be established. Summary of the Invention

[0007] The purpose of this invention is to address the shortcomings of the prior art by providing a construction method for prefabricated, assembled, ultra-high-performance concrete exterior panels using columns. This method employs a special structural design and a pouring and curing process involving segmented templates, continuous segmented pouring, and timely steam curing, thereby solving the technical problems of guardrail panel replacement and the repair and reinforcement of old columns.

[0008] The objective of this invention is achieved through the following technical solutions: A construction method for prefabricated ultra-high performance concrete exterior panels using columns, characterized by the following steps: The precast and assembled ultra-high performance concrete exterior panels are poured in sections. Each precast and assembled ultra-high performance concrete exterior panel includes an exterior facade and an L-shaped section that matches the column. The L-shaped section includes an L-shaped structure that can surround the column from two opposite directions. First, pour the exterior facade of the precast and assembled ultra-high performance concrete exterior panel. Then, pour the L-shaped part of the precast and assembled ultra-high performance concrete exterior panel within a certain time, so that the ultra-high performance concrete poured in the two times can be fully mixed to form a whole. Install two prefabricated ultra-high performance concrete exterior panels with opposite L-shaped sections, surround the column with the opposite L-shaped sections, and pour ultra-high performance concrete between the ultra-high performance concrete exterior panels and the column for conventional curing.

[0009] The exterior facade of the precast ultra-high performance concrete exterior panel is achieved by the cooperation of a smooth plastic mold, plywood, and limiting components. A groove-shaped casting area for the exterior facade is provided on one side of the smooth plastic mold. The limiting components are provided on both sides of the smooth plastic mold outside the groove-shaped casting area for limiting support. The plywood is provided on the other side of the smooth plastic mold.

[0010] The L-shaped portion of the precast assembled ultra-high performance concrete exterior panel is achieved through the cooperation of a molding template, a detachable and combinable wooden support, and a limiting component. The molding template surrounds the casting area of ​​the L-shaped portion, and the detachable and combinable wooden support and the limiting component are both used to limit and support the molding template.

[0011] The molding template is provided with vent holes, which have removable plugs.

[0012] Twelve hours after the precast ultra-high performance concrete exterior panels are poured, the formwork is immediately removed, and a steam curing shed is immediately covered for steam curing. The temperature is raised to 90±5℃ at a rate not exceeding 12℃ / h and held at that temperature for 48 hours. Then, the temperature is lowered to ambient temperature at a rate not exceeding 15℃ / h.

[0013] Spraying moisture at the pouring overlap between the exterior facade section and the L-shaped section of the precast assembled ultra-high performance concrete exterior panel, and then tamping with reinforcing bars.

[0014] The advantages of this invention are: (1) Using prefabricated UHPC as the exterior panel results in better durability and a longer lifespan; due to its hydrophobic properties, the finished product is more resistant to dirt and has better color and texture effects.

[0015] (2) The entire structure does not require steel structure, which reduces costs and greatly reduces construction difficulty. Prefabrication in sections greatly reduces hoisting weight and hoisting construction difficulty.

[0016] (3) Under the same load, compared with the external installation of decorative panels of the same size, this technology can effectively reduce the principal tensile stress of the structure.

[0017] (4) While constructing the decorative railing, the purpose of repairing and reinforcing the columns can be achieved.

[0018] (5) The modular mold design reduces the risk of "molding expansion", lowers the requirements for templates, reduces construction difficulty and construction cost, and improves construction efficiency.

[0019] (6) Steam curing should be carried out immediately after demolding, which can quickly improve the strength of UHPC and further reduce the later shrinkage of UHPC, thereby reducing the risk of component cracking.

[0020] (7) Steam curing greatly shortens the curing time and improves construction efficiency. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the single prefabricated ultra-high performance concrete exterior panel in this invention; Figure 2 This is a schematic diagram of the structure of two prefabricated, assembled ultra-high performance concrete exterior panels in this invention; Figure 3 This is a schematic diagram of the casting of the exterior facade of the prefabricated ultra-high performance concrete exterior panel in this invention. Figure 4 This is a schematic diagram of the L-shaped section of the prefabricated ultra-high performance concrete exterior panel in this invention. Figure 5 This is a schematic diagram of the installation structure of the prefabricated and assembled ultra-high performance concrete exterior panels and columns in this invention. Detailed Implementation

[0022] The features and other related features of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments, so as to facilitate understanding by those skilled in the art: like Figure 1-5As shown in the figure, labels 1-18 represent: 1. Precast assembled ultra-high performance concrete exterior panel; 2. Exterior facade section; 3. L-shaped section; 4. First exterior panel; 5. Second exterior panel; 6. L-shaped section; 7. Ultra-high performance concrete exterior panel; 8. Smooth plastic mold; 9. Plywood; 10. Limiting component; 11. Limiting component; 12. Vent hole; 13. Limiting component; 14. Demountable and combinable wooden support; 15. UHPC pouring port; 16. Column; 17. UHPC pouring area; 18.

[0023] Example: Figures 1 to 5 As shown, this embodiment utilizes a prefabricated assembly method for ultra-high performance concrete exterior panels on columns to manufacture the exterior panels outside the columns. Specifically, it includes the following steps: 1) The prefabricated ultra-high performance concrete exterior panel 1 is poured in sections. Each prefabricated ultra-high performance concrete exterior panel includes the exterior facade part 2 and the L-shaped part 3 that matches the column. By utilizing the original column, it is possible to achieve the construction of prefabricated exterior panels without steel components, and to repair and reinforce the old column.

[0024] Combination Figure 1 and Figure 2 As shown, the L-shaped portion 3 includes an L-shaped structure that can surround the column from two opposite directions, so that the prefabricated ultra-high performance concrete exterior panel 1 in this embodiment is actually divided into two structures, namely the first exterior panel 4 and the second exterior panel 5. The L-shaped portion 6 provided on the first exterior panel 4 and the L-shaped portion 7 provided on the second exterior panel 5 have the same size and structural form, but the opening direction is opposite, so that after the two exterior panels are constructed, the L-shaped portions of the two panels can fit together to surround the outside of the column.

[0025] 2) Divide the roof truss where the columns are located into sections, with each section being 3-5m in length, and install baffles at the joints between the sections.

[0026] 3) First, pour the precast and assembled ultra-high performance concrete exterior panel 1 for the exterior facade part 2. This can not only ensure the aesthetic effect of the exterior facade display part, but also reduce the risk of "formwork bulging", reduce the requirements for the formwork, and reduce costs.

[0027] like Figure 3 As shown, a casting mold for the exterior facade 2 is constructed by using a smooth plastic mold 9, plywood 10, and limiting members 11. A recessed casting area for the exterior facade 2 is provided on one side of the smooth plastic mold 9. Limiting members 11 are provided on both sides of the smooth plastic mold 9 outside this recessed casting area for limiting and support. Plywood 10 is provided on the other side of the smooth plastic mold 9. Figure 3 In the middle, the groove-shaped casting area on the smooth rubber mold 9 has been filled with ultra-high performance concrete 8 for the exterior facade.

[0028] In this embodiment, after the outer facade 2 is poured, its surface is immediately sprayed and covered with a curing film.

[0029] 3) Pour the L-shaped part 3 of the precast and assembled ultra-high performance concrete exterior panel 1 within a certain time, so that the ultra-high performance concrete poured twice can be fully mixed to form a whole.

[0030] The L-shaped portion 3 of the precast assembled ultra-high performance concrete (UHPC) exterior panel 1 is achieved through the cooperation of a molding template, a detachable and combinable wooden support 15, and limiting components 12 and 14. The molding template encloses the pouring area of ​​the L-shaped portion 3, and the detachable and combinable wooden support 15, limiting components 12 and 14 are used to limit and support the molding template. A vent 13 is provided on the molding template, and this vent 13 has a removable plug. This vent ensures the connection quality between the two pours of UHPC.

[0031] In this embodiment, the interval between pouring two adjacent segments (exterior facade section 2 and L-shaped section 3) is controlled within 20 minutes. Moisturizing is sprayed at the overlap of the two UHPC pours, and steel bars are used for tamping to ensure that the two UHPC pours are fully mixed into a whole.

[0032] 4) 12 hours after the pouring is completed, the formwork is removed immediately, and the steam curing shed is covered immediately for steam curing. The temperature is raised to 90±5℃ at a rate not exceeding 12℃ / h and kept constant for 48 hours. Then the temperature is lowered to ambient temperature at a rate not exceeding 15℃ / h.

[0033] 5) Once steam curing is complete, the components can be put into use.

[0034] Two prefabricated, high-performance concrete exterior panels 1 with opposite L-shaped sections are used to enclose the L-shaped sections 3 facing opposite directions around the perimeter of the column. For example... Figure 5 As shown, the first exterior panel 4 and the second exterior panel 5 are placed on the outside of the column 17 and the L-shaped parts of the two exterior panels are arranged to surround the perimeter of the column 17. Ultra-high performance concrete is poured in the UHPC casting area 18 between the two L-shaped parts and the column 17, so that the prefabricated assembled ultra-high performance concrete exterior panel 1 and the column 17 are effectively connected and then routinely cured.

[0035] Although the above embodiments have described the concept and embodiments of the present invention in detail with reference to the accompanying drawings, those skilled in the art will recognize that various improvements and modifications can still be made to the present invention without departing from the scope of the claims, and therefore will not be elaborated here.

Claims

1. A construction method for prefabricated, assembled ultra-high performance concrete exterior panels using columns, characterized in that: The construction method includes the following steps: The precast and assembled ultra-high performance concrete exterior panels are poured in sections. Each precast and assembled ultra-high performance concrete exterior panel includes an exterior facade and an L-shaped section that matches the column. The L-shaped section includes an L-shaped structure that can surround the column from two opposite directions. First, pour the exterior facade of the precast and assembled ultra-high performance concrete exterior panel. Then, pour the L-shaped part of the precast and assembled ultra-high performance concrete exterior panel within a certain time, so that the ultra-high performance concrete poured in the two times can be fully mixed to form a whole. Install two prefabricated ultra-high performance concrete exterior panels with opposite L-shaped sections, surround the column with the opposite L-shaped sections, and pour ultra-high performance concrete between the ultra-high performance concrete exterior panels and the column for conventional curing.

2. The construction method for prefabricated ultra-high performance concrete exterior panels using columns as described in claim 1, characterized in that: The exterior facade of the precast ultra-high performance concrete exterior panel is achieved by the cooperation of a smooth plastic mold, plywood, and limiting components. A groove-shaped casting area for the exterior facade is provided on one side of the smooth plastic mold. The limiting components are provided on both sides of the smooth plastic mold outside the groove-shaped casting area for limiting support. The plywood is provided on the other side of the smooth plastic mold.

3. The construction method for prefabricated ultra-high performance concrete exterior panels using columns as described in claim 1, characterized in that: The L-shaped portion of the precast assembled ultra-high performance concrete exterior panel is achieved through the cooperation of a molding template, a detachable and combinable wooden support, and a limiting component. The molding template surrounds the casting area of ​​the L-shaped portion, and the detachable and combinable wooden support and the limiting component are both used to limit and support the molding template.

4. The construction method for prefabricated ultra-high performance concrete exterior panels using columns as described in claim 3, characterized in that: The molding template is provided with vent holes, which have removable plugs.

5. The construction method for prefabricated ultra-high performance concrete exterior panels using columns as described in claim 1, characterized in that: Twelve hours after the precast ultra-high performance concrete exterior panels are poured, the formwork is immediately removed, and a steam curing shed is immediately covered for steam curing. The temperature is raised to 90±5℃ at a rate not exceeding 12℃ / h and held at that temperature for 48 hours. Then, the temperature is lowered to ambient temperature at a rate not exceeding 15℃ / h.

6. The construction method for prefabricated ultra-high performance concrete exterior panels using columns as described in claim 1, characterized in that: Spraying moisture at the pouring overlap between the exterior facade section and the L-shaped section of the precast assembled ultra-high performance concrete exterior panel, and then tamping with reinforcing bars.

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