CN111236535A - Reinforced concrete composite column and construction method thereof - Google Patents

Abstract

The invention provides a reinforced concrete composite column and a construction method thereof, wherein the composite column comprises a concrete canvas layer, a fiber reinforced material cloth layer and a PVC pipe, wherein the concrete canvas layer is sleeved outside the fiber reinforced material cloth layer, the PVC pipe is sleeved inside the fiber reinforced material cloth layer, a concrete column core is poured inside the PVC pipe, and a plurality of longitudinal stress ribs and transverse stirrups are embedded in the concrete column core; the concrete canvas layer comprises canvas, cement powder and short fibers; the canvas is a three-dimensional fabric, and the cement powder and the short fibers are uniformly distributed in the three-dimensional structure of the canvas. The core concrete in the combined column is in a three-dimensional compression state, so that the bearing performance and the ductility performance of the concrete column are improved, the anti-seismic performance of the combined column is also obviously enhanced, and the wrapped improved concrete canvas can improve the high-temperature resistance of the combined column.

Description

A kind of reinforced concrete composite column and its construction method

【Technical field】

The invention relates to the field of civil engineering, in particular to a reinforced concrete composite column and a construction method thereof.

【Background technique】

The prefabricated pipes currently used in concrete composite columns include PVC pipes, fiber reinforced composite pipes, steel pipes, or composite pipes combining the above two. These prefabricated tubes can serve three functions: one is to act as a formwork for pouring concrete; the other is to provide restraint to the core concrete inside; the third is to provide flexural and shear strength for the composite concrete column. However, CFST composite columns are susceptible to corrosion. Although PVC or fiber-reinforced composite materials are corrosion-resistant, their mechanical properties will decline after exposure to thermal environments (fire), and the thin walls of pipes made of PVC or fiber-reinforced composite materials make Their lateral stiffness is not enough, and the section is prone to deformation during the concrete pouring process, especially at the column foot position, resulting in the actual section size being larger than the design size.

[Content of the invention]

One of the technical problems to be solved by the present invention is to provide a reinforced concrete composite column, the inner core concrete of which is in a three-way compression state, thereby improving the bearing performance and ductility performance of the concrete column, and its seismic performance is also significantly enhanced. The wrapped modified concrete canvas can improve the high temperature resistance of the composite column.

The present invention realizes one of the above problems in this way:

A reinforced concrete composite column comprises a concrete canvas layer, a fiber reinforced material cloth layer and a PVC pipe, the concrete canvas layer is wound on the outside of the fiber reinforced material cloth layer, and the outside of the PVC pipe is sleeved inside the fiber reinforced material cloth layer, A concrete column core is poured inside the PVC pipe, and a plurality of longitudinal reinforcement bars and transverse stirrups are embedded in the concrete column core.

Further, the concrete canvas layer includes canvas, cement powder and short fibers; the canvas is a three-dimensional fabric cloth, and the cement powder and short fibers are uniformly distributed in the three-dimensional structure of the canvas.

Further, the short fibers are steel fibers, basalt fibers, carbon fibers or glass fibers.

Further, the weight of the short fibers is 2%-3% of the weight of the cement powder.

Further, the material of the fiber reinforced material cloth layer is glass fiber cloth, basalt fiber cloth or carbon fiber cloth.

Further, the fiber reinforced material cloth layer is made of unidirectional fiber cloth or bidirectional fiber cloth.

Further, the longitudinal reinforcement bars are steel bars, glass fiber bars, basalt fiber bars or carbon fiber bars.

The second technical problem to be solved by the present invention is to provide a construction method for a reinforced concrete composite column. The core concrete of the prepared product is in a state of three-way compression, thereby improving the bearing performance and ductility performance of the concrete column, and its seismic resistance The performance is also significantly enhanced, while the wrapped modified concrete canvas can improve the high temperature resistance of the composite column.

The present invention achieves the second problem above:

A construction method of a reinforced concrete composite column is carried out according to the following steps:

(1) Composite material pipe of prefabricated composite column: wrap 1-3 layers of fiber reinforced material cloth on the outside of the PVC pipe, and then continue to wrap 1-3 layers of concrete canvas on the outside of the fiber reinforced material cloth;

(2) Reinforcement: Arrange a certain number of longitudinally stressed steel bars, and then set up multiple transverse stirrups to encircle multiple longitudinally stressed steel bars and place them in the PVC pipe;

(3) Pouring: pour concrete into the PVC pipe to obtain a reinforced concrete composite column.

Further, the concrete canvas includes canvas, cement powder and short fibers;

The canvas is a three-dimensional fabric cloth, and the cement powder and short fibers are evenly distributed in the three-dimensional structure of the canvas;

The short fibers are steel fibers, basalt fibers, carbon fibers or glass fibers;

The weight of the short fibers is 2%-3% of the weight of the cement powder.

Further, the fiber reinforcement cloth is made of glass fiber cloth, basalt fiber cloth or carbon fiber cloth; the fiber reinforcement cloth is made of unidirectional fiber cloth or bidirectional fiber cloth;

The longitudinal reinforcement bars are steel bars, glass fiber bars, basalt fiber bars or carbon fiber bars.

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

The composite column is made of improved concrete canvas (CC), fiber reinforced material cloth (FRP) and PVC pipe as a formwork for concrete pouring. Because the CC-FRP-PVC composite pipe makes the inner core The concrete is in a three-way compression state to improve the strength of the concrete in the tube, thereby improving the bearing performance and ductility of the concrete column, and its seismic performance is also significantly enhanced. That is, the PVC pipe can be used as a formwork for pouring the inner core concrete, and the outer fiber reinforced material cloth can provide hoop restraint strength to the inner core concrete and the PVC pipe, and the improved concrete canvas pipe mixed with short fiber reinforced material can be used in the fiber reinforced material cloth. The outer side of the pipe can provide sufficient rigidity for the inner PVC and fiber cloth pipes, and at the same time can make the inner PVC and fiber cloth pipes resist high temperature. In addition, the existing concrete canvas is improved by incorporating short fiber reinforced materials, so as to improve the durability and ductility of the concrete canvas, thereby improving the durability of the composite column of the present invention, so that the composite column of the present invention can withstand high temperature, sea, humidity and other conditions. It has good adaptability in harsh environments such as saline-alkali land.

【Description of drawings】

The present invention will be further described below with reference to the accompanying drawings and embodiments.

FIG. 1 is a schematic structural diagram of a reinforced concrete composite column of the present invention.

【Detailed ways】

Referring to FIG. 1, the present invention relates to a reinforced concrete composite column, comprising a concrete canvas layer 1, a fiber reinforced material cloth layer 2 and a PVC pipe 3, the concrete canvas layer 1 is wound on the outside of the fiber reinforced material cloth layer 2, and the PVC The outside of the pipe 3 is sheathed inside the fiber reinforced material cloth layer 2, and a concrete column core 4 is poured inside the PVC pipe 3, and a plurality of longitudinal stress bars 5 and transverse stirrups 6 are embedded in the concrete column core 4.

The concrete canvas layer 1 includes canvas, cement powder and short fibers; the canvas is a three-dimensional fabric cloth, and the cement powder and short fibers are uniformly distributed in the three-dimensional structure of the canvas.

The short fibers are steel fibers, basalt fibers, carbon fibers or glass fibers.

The weight of the short fibers is 2%-3% of the weight of the cement powder.

The fiber reinforced material cloth layer 2 is made of glass fiber cloth, basalt fiber cloth or carbon fiber cloth.

The fiber reinforced material cloth layer 2 is made of unidirectional fiber cloth or bidirectional fiber cloth.

The longitudinal reinforcement bars 5 are steel bars, glass fiber bars, basalt fiber bars or carbon fiber bars.

The present invention also relates to a construction method of the above-mentioned reinforced concrete composite column, which is carried out according to the following steps:

(1) Composite material pipe of prefabricated composite column: wrap 1-3 layers of fiber reinforced material cloth layer 2 on the outside of PVC pipe 3, and then continue to wrap 1-3 layers of concrete canvas layer 1 on the outside of fiber reinforced material cloth layer 2;

(2) Reinforcement: Arrange a certain number of longitudinally stressed steel bars 5, and then set multiple transverse stirrups 6 to encircle multiple longitudinally stressed steel bars 5 at the same time, and place them in the PVC pipe 3;

(3) Pouring: pour concrete into the PVC pipe 3 to obtain a reinforced concrete composite column.

The present invention will be further described below in conjunction with specific embodiments.

Example

A reinforced concrete composite column is constructed and prepared according to the following steps:

(1) Prefabricated CC-FRP-PVC composite material pipe: first select the size of the PVC pipe according to the design requirements; then clean the outer surface of the PVC pipe, apply epoxy resin glue, and wrap the first layer of fiber reinforced material cloth ( FRP), continue to brush epoxy resin glue on the surface of the first layer of fiber reinforced material cloth, wind the second layer of fiber reinforced material cloth, repeat the previous operation to continue winding the fiber reinforced material cloth, the number of layers of fiber reinforced material cloth depends on the design (generally 1-3 layers), the winding height is the same as the height of the PVC pipe; finally, after waiting for the epoxy resin glue on the fiber reinforced material cloth to form strength, the first layer is filled with cement powder and short fiber concrete canvas ( CC) wrapped on the surface of the fiber reinforced material cloth, then sprayed with water to harden it, and then repeated the operation of the first layer to form the second layer of concrete canvas, the number of layers of the concrete canvas depends on the design (generally 1-3 layers) , the winding height is the same as the height of the PVC pipe, and finally the CC-FRP-PVC composite pipe is made;

(2) Reinforcement: Arrange a certain number of longitudinally stressed steel bars according to the design requirements, and then set up multiple stirrups to encircle multiple longitudinally stressed steel bars at the same time to form a steel reinforcement cage, which is placed inside the PVC pipe;

(3) Pouring: pouring concrete into the PVC pipe, and burying the reinforcement cage of step (2) in the concrete.

Compared with the prior art, the reinforced concrete composite column of the present invention has the following advantages: (1) based on the restraining effect of the CC-FRP-PVC composite material pipe on the inner core concrete, the section size can be reduced under the same vertical load, and the It can effectively solve the shortcomings of reinforced concrete structure with heavy self-weight and low bearing capacity; (2) It can improve the ductility performance of reinforced concrete columns and ensure that the columns can still be used normally under the action of strong earthquakes; (3) CC-FRP-PVC composite material The mutual cooperation of the materials in the pipe, the concrete canvas can solve the shortcomings of the poor fire resistance and low lateral stiffness of the reinforced concrete column of the FRP pipe or the PVC pipe. Due to the disadvantage of poor performance, it has broad application prospects and development space in the fields of bridges, buildings and underground piles in coastal and corrosive areas.

Although the specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments we describe are only illustrative, rather than used to limit the scope of the present invention. Equivalent modifications and changes made by a skilled person in accordance with the spirit of the present invention should be included within the scope of protection of the claims of the present invention.

Claims (10)

1. A reinforced concrete composite column is characterized in that: comprising a concrete canvas layer, a fiber-reinforced material cloth layer and a PVC pipe, the concrete canvas layer is wound on the outside of the fiber-reinforced material cloth layer, and the PVC pipe is externally sleeved on the fiber Inside the reinforcing material cloth layer, a concrete column core is poured inside the PVC pipe, and a plurality of longitudinal stress bars and transverse stirrups are embedded in the concrete column core. 2. A reinforced concrete composite column according to claim 1, characterized in that: the concrete canvas layer comprises canvas, cement powder and short fibers; the canvas is a three-dimensional fabric cloth, and the cement powder and short fibers are uniform distributed within the three-dimensional structure of the canvas. 3 . The reinforced concrete composite column according to claim 2 , wherein the short fibers are steel fibers, basalt fibers, carbon fibers or glass fibers. 4 . 4. A reinforced concrete composite column according to claim 2 or 3, wherein the weight of the short fibers is 2%-3% of the weight of the cement powder. 5 . The reinforced concrete composite column according to claim 1 , wherein the fiber reinforced material cloth layer is made of glass fiber cloth, basalt fiber cloth or carbon fiber cloth. 6 . 6. A reinforced concrete composite column according to claim 1 or 5, wherein the fiber reinforced material cloth layer is made of unidirectional fiber cloth or bidirectional fiber cloth. 7 . The reinforced concrete composite column according to claim 1 , wherein the longitudinal stress-bearing bars are steel bars, glass fiber bars, basalt fiber bars or carbon fiber bars. 8 . 8. a construction method of reinforced concrete composite column is characterized in that: carry out according to the following steps: (1) Composite material pipe of prefabricated composite column: wrap 1-3 layers of fiber reinforced material cloth on the outside of the PVC pipe, and then continue to wrap 1-3 layers of concrete canvas on the outside of the fiber reinforced material cloth; (2) Reinforcement: Arrange a certain number of longitudinally stressed steel bars, and then set up multiple transverse stirrups to encircle multiple longitudinally stressed steel bars and place them in the PVC pipe; (3) Pouring: pour concrete into the PVC pipe to obtain a reinforced concrete composite column. 9. The construction method of a reinforced concrete composite column according to claim 8, wherein the concrete canvas comprises canvas, cement powder and short fibers; The canvas is a three-dimensional fabric cloth, and the cement powder and short fibers are evenly distributed in the three-dimensional structure of the canvas; The short fibers are steel fibers, basalt fibers, carbon fibers or glass fibers; The weight of the short fibers is 2%-3% of the weight of the cement powder. 10. The construction method of a reinforced concrete composite column according to claim 8, characterized in that: the material of the fiber-reinforced material cloth is glass fiber cloth, basalt fiber cloth or carbon fiber cloth; the fiber-reinforced material cloth is Made of unidirectional fiber cloth or bidirectional fiber cloth; The longitudinal reinforcement bars are steel bars, glass fiber bars, basalt fiber bars or carbon fiber bars.

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