CN112726959A - High-strength concrete composite column with high-strength steel pipes and internally-arranged FRP pipes - Google Patents
High-strength concrete composite column with high-strength steel pipes and internally-arranged FRP pipes Download PDFInfo
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- CN112726959A CN112726959A CN202110013845.4A CN202110013845A CN112726959A CN 112726959 A CN112726959 A CN 112726959A CN 202110013845 A CN202110013845 A CN 202110013845A CN 112726959 A CN112726959 A CN 112726959A
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- strength steel
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 76
- 239000010959 steel Substances 0.000 title claims abstract description 76
- 239000011372 high-strength concrete Substances 0.000 title claims abstract description 52
- 239000002131 composite material Substances 0.000 title claims abstract description 17
- 239000004567 concrete Substances 0.000 claims abstract description 30
- 238000010276 construction Methods 0.000 claims description 7
- 239000000463 material Substances 0.000 claims description 5
- 239000002699 waste material Substances 0.000 claims description 4
- 229920000049 Carbon (fiber) Polymers 0.000 claims description 3
- 229920006231 aramid fiber Polymers 0.000 claims description 3
- 239000004917 carbon fiber Substances 0.000 claims description 3
- 239000003365 glass fiber Substances 0.000 claims description 3
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 3
- 239000004576 sand Substances 0.000 claims description 3
- 239000013535 sea water Substances 0.000 claims description 3
- 230000008901 benefit Effects 0.000 abstract description 7
- 230000006835 compression Effects 0.000 abstract description 6
- 238000007906 compression Methods 0.000 abstract description 6
- 238000005452 bending Methods 0.000 abstract description 4
- 238000005265 energy consumption Methods 0.000 abstract description 2
- 230000000452 restraining effect Effects 0.000 abstract 1
- 230000007547 defect Effects 0.000 description 7
- 239000004744 fabric Substances 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000009977 dual effect Effects 0.000 description 2
- 239000003733 fiber-reinforced composite Substances 0.000 description 2
- 230000002045 lasting effect Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 239000004566 building material Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012761 high-performance material Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000021715 photosynthesis, light harvesting Effects 0.000 description 1
- 238000009417 prefabrication Methods 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
- E04C3/00—Structural elongated elements designed for load-supporting
- E04C3/30—Columns; Pillars; Struts
- E04C3/34—Columns; Pillars; Struts of concrete other stone-like material, with or without permanent form elements, with or without internal or external reinforcement, e.g. metal coverings
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/62—Insulation or other protection; Elements or use of specified material therefor
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/62—Insulation or other protection; Elements or use of specified material therefor
- E04B1/92—Protection against other undesired influences or dangers
- E04B1/98—Protection against other undesired influences or dangers against vibrations or shocks; against mechanical destruction, e.g. by air-raids
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04H—BUILDINGS OR LIKE STRUCTURES FOR PARTICULAR PURPOSES; SWIMMING OR SPLASH BATHS OR POOLS; MASTS; FENCING; TENTS OR CANOPIES, IN GENERAL
- E04H9/00—Buildings, groups of buildings or shelters adapted to withstand or provide protection against abnormal external influences, e.g. war-like action, earthquake or extreme climate
- E04H9/02—Buildings, groups of buildings or shelters adapted to withstand or provide protection against abnormal external influences, e.g. war-like action, earthquake or extreme climate withstanding earthquake or sinking of ground
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- Engineering & Computer Science (AREA)
- Architecture (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Environmental & Geological Engineering (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Rod-Shaped Construction Members (AREA)
Abstract
The invention relates to a high-strength concrete combination column with a high-strength steel pipe restraining built-in FRP pipes, which comprises the high-strength steel pipe positioned on the outermost side, at least one FRP pipe positioned in the high-strength steel pipe and a high-strength concrete layer filled between the outer wall of the FRP pipe and the inner wall of the high-strength steel pipe, wherein a high-strength concrete core column is fixedly arranged in each FRP pipe, and the extending direction of the FRP pipe is parallel to the extending direction of the high-strength concrete layer. The high-strength steel pipe is positioned on the outermost side of the section, has higher rigidity and plasticity energy consumption capability, can provide compression resistance and tensile resistance in bending, and can ensure that the member has good seismic performance; the core concrete column wrapped by the FRP pipe fully exerts the advantages of high tensile strength and anisotropy of the composite material, is not influenced by axial pressure, forms strong and continuous constraint on the core concrete, and provides higher axial bearing capacity and ductility for the member. The round FRP pipe is arranged in concrete, so that the problem of poor fireproof performance of the composite material can be better solved.
Description
Technical Field
The invention belongs to the field of building structures, and particularly relates to a high-strength concrete composite column with a high-strength steel pipe and a built-in FRP pipe.
Background
At present, China enters the rapid development period of urbanization, the demand for heavy-load structures such as large-span structures and super high-rise structures is increased rapidly, and the traditional building materials and structures are difficult to meet the requirements. Therefore, the popularization and application of various high-performance materials are rapidly developed, for example: high-strength steel, high-strength concrete and fiber reinforced composite materials, thereby establishing a low-consumption and low-carbon-emission conservation-oriented society and realizing harmonious development of human and nature and social sustainable development.
However, high-strength steel, high-strength concrete and FRP composite materials all have inherent defects, and the application and development of the composite materials as column members in civil engineering are severely restricted. Along with the increase of the yield strength of the steel, the yield ratio is increased, the elongation after fracture is reduced, the length of a yield platform is shortened or even disappears, and the strain strengthening effect of the high-strength steel is not obvious; in addition, in the high-strength pure steel structure, the high-strength steel has higher strength, and the steel plate is thinner than common steel, so that local buckling is more likely to occur under the condition of no constraint under pressure, and the material strength cannot be fully utilized; although the high-strength concrete has high strength, the defects of high brittleness and poor ductility also severely limit the application of the high-strength concrete as a column; the composite material is inconvenient to carry out beam column node connection after being formed, has poor fireproof performance and is not beneficial to popularization and application in actual engineering.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a high-strength concrete composite column with a built-in FRP pipe constrained by a high-strength steel pipe, which overcomes the defects that local buckling is easy to occur in the application of the column in a high-strength steel compression state and the concrete in the steel pipe concrete column is not constrained enough, obviously improves the bearing capacity and ductility of a member, can adopt smaller section size under the same stress condition, greatly reduces the steel consumption and self weight, not only can further improve the safety and reliability of the structure, but also can create larger building use space and realize more flexible building performance.
In order to achieve the purpose, the invention adopts the following technical scheme:
the utility model provides a high-strength concrete combination column of built-in FRP pipe of high-strength steel pipe restraint, is located at least one FRP pipe of high-strength steel pipe and fills the high-strength concrete layer between FRP pipe outer wall and the high-strength steel pipe inner wall including the high-strength steel pipe that is located the outside, wherein, the intraductal all fixed core column that is provided with high-strength concrete of every FRP, FRP pipe extending direction is parallel with high-strength concrete layer extending direction.
Further, the FRP pipe may have any one of a circular, square, and rectangular cross section.
Furthermore, the FRP pipe is made of any material of carbon fiber, glass fiber and aramid fiber.
Furthermore, the high-strength steel pipes are all high-strength square steel pipes. Compared with the cross section forms such as round steel pipes and section steel, the cross section area, the steel consumption and the self weight can be smaller, and the better bearing capacity, ductility and seismic performance can be obtained.
Furthermore, the high-strength steel pipes are all made of steel with the strength grade of Q690 or above.
Further, the high-strength concrete is made of concrete with a concrete strength grade of C50 or above.
Further, the high-strength concrete core column is made of any one of construction waste concrete, recycled aggregate concrete and seawater sea sand concrete.
Compared with the prior art, the invention has the following beneficial effects:
1. set up at least one FRP pipe in the high-strength steel pipe, introduce the fiber reinforced composite FRP structural engineering field, full play FRP tensile strength is big, anisotropic advantage, do not receive the influence of axial compression, form very strong and lasting restraint to the core concrete, for the component provides higher axial bearing capacity and ductility, solved concrete lack the problem of restraint and round steel pipe restraint concrete easy yield under triaxial stress state among the traditional square steel pipe concrete.
2. The external high-strength steel pipe has high rigidity and can provide compression resistance and tensile resistance in bending. The high-strength steel pipe is arranged on the outermost side of the cross section, can generate an interaction relation with a concrete core column wrapped by the internal FRP pipe, forms double restraint on the core concrete column, and improves the transverse deformation capacity and the bending bearing capacity. Meanwhile, the external high-strength steel pipe has higher rigidity and plasticity energy consumption capability, so that the member has good anti-seismic performance.
3. Generally, high-strength concrete expands and deforms transversely when bearing longitudinal load, and brittle failure easily occurs. Under the dual constraints of the high-strength steel pipe and the built-in FRP pipe, the transverse expansion deformation of the high-strength concrete column is effectively inhibited bidirectionally, the strength and the ductility are greatly improved, and the defect of easy brittle failure is overcome.
4. The high-strength steel pipes and the FRP pipes on the outer sides can be used as templates, so that a factory prefabrication mode is adopted conveniently, and the construction efficiency is improved. The template cost can be saved, and the economic benefit is improved. In addition, the concrete pouring operation of the main components can be completed by adopting a factory prefabricating method, the main components are quickly lapped on a construction site, and the construction efficiency is improved.
5. The FRP pipe is strong in corrosion resistance, and the internal high-strength concrete core column can be made of environment-friendly concrete, so that sustainable development can be realized, and economic benefits are improved. Because the FRP pipe has stronger corrosion resistance, environment-friendly concrete such as construction waste concrete, recycled aggregate concrete, seawater and sea sand concrete and the like can be sealed and filled in the FRP pipe, and the purpose of sustainable development of waste material utilization is achieved.
6. The combined column overcomes the defects that the high-strength steel is easy to partially buckle and the ductility of the high-strength concrete is poor in the compressed state in the application of the column, fully utilizes the advantages of high tensile strength of the high-strength steel and high compressive strength of the high-strength concrete, has higher strength and better ductility, can adopt smaller section size under the same stress condition, greatly reduces the steel consumption and the structural weight, can further improve the safety and reliability of the structure, can create larger building use space, and realizes more flexible building performance.
Drawings
Fig. 1 is a schematic perspective view of an embodiment of the present invention.
Fig. 2 is a cross-sectional view of an embodiment of the present invention.
Description of reference numerals:
1-high-strength steel pipe; 2-high-strength concrete layer; 3-FRP pipe; 4-high-strength concrete core column.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples.
The utility model provides a high-strength concrete combination column of built-in FRP pipe of high-strength steel pipe restraint, is including being located the high-strength steel pipe 1 in the outside, being located at least one FRP pipe 3 in the high-strength steel pipe and filling the high-strength concrete layer 2 between FRP pipe outer wall and the high-strength steel pipe inner wall, wherein, the intraductal all fixed high-strength concrete core column 4 that is provided with of every FRP, FRP pipe extending direction is parallel with high-strength concrete layer extending direction.
Specifically, the high-strength steel pipe 1 is vertically disposed. The FRP pipe 3 is arranged in the high-strength steel pipe 1, and the high-strength steel pipe 1 and the FRP pipe 3 are arranged in parallel. And a high-strength concrete layer 2 is poured between the high-strength steel pipe 1 and the FRP pipe 3, and a high-strength concrete core column 4 is poured in the FRP pipe.
In this embodiment, please refer to fig. 1 and 2, only one FRP pipe is provided. The high-strength steel pipe is positioned on the outermost side, has higher rigidity and plasticity energy dissipation capacity, can provide compression resistance and tensile strength in bending, and can ensure that the member has good anti-seismic performance; and inside by FRP pipe parcel's high strength concrete core column then full play the combined material tensile strength big, anisotropic advantage, do not receive the influence of axial compression, form very strong and lasting restraint to core concrete, provide higher axial bearing capacity and ductility for the component. In other embodiments, multiple FRP tubes may be provided as needed to further enhance the axial load bearing and ductility of the composite column.
In general, the high-strength concrete 4 is likely to undergo lateral expansion deformation and brittle failure when subjected to a longitudinal load. According to the invention, under the dual constraints of the high-strength steel pipe 1 and the built-in FRP pipe 3, the transverse expansion deformation of the high-strength concrete 4 is inhibited in two directions, the strength and the ductility are greatly improved, and the defect of easy brittle failure is overcome.
The combined column overcomes the defects that the high-strength steel is easy to generate local buckling and the ductility of the high-strength concrete is poor in the application of the column in a compressed state, fully utilizes the advantages of high tensile strength of the high-strength steel and high compressive strength of the high-strength concrete, and has higher strength and better ductility; the fire resistance and the durability are better; not only can further improve the security and the reliability of structure, but also can create bigger building usage space, realize more nimble building performance.
The FRP pipe may have any one of a circular, square and rectangular cross section. In this embodiment, the FRP pipe has a circular cross section.
The section of the high-strength steel pipe may be any one of circular, square and rectangular. In this embodiment, the cross section of the high-strength steel pipe is square. Under the same stress condition, the cross section size can be smaller, the steel consumption and the structural weight are greatly reduced, the template is saved, and the construction is more convenient.
The high-strength steel pipe is made of steel with the strength grade of Q690 or above.
The FRP pipe can be formed by winding glass fiber cloth, carbon fiber cloth or aramid fiber cloth.
The high-strength concrete core column and the high-strength concrete layer can be made of concrete with the concrete strength grade of C50 or above.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (8)
1. The utility model provides a high-strength concrete combination column of built-in FRP pipe of high-strength steel pipe restraint which characterized in that: including the high-strength steel pipe that is located the outside, be located at least one FRP pipe in the high-strength steel pipe and fill the high-strength concrete layer between FRP pipe outer wall and high-strength steel pipe inner wall, wherein, all fixedly in every FRP pipe is provided with high-strength concrete core column, FRP pipe extending direction is parallel with high-strength concrete layer extending direction.
2. The high-strength concrete composite column with the high-strength steel pipes and the internally-arranged FRP pipes as claimed in claim 1, wherein: the FRP pipe may have any one of a circular, square and rectangular cross section.
3. The high-strength concrete composite column with the high-strength steel pipes and the internally-arranged FRP pipes as claimed in claim 1, wherein: the section of the high-strength steel pipe may be any one of circular, square and rectangular.
4. The high-strength concrete composite column with the high-strength steel pipes and the internally-arranged FRP pipes as claimed in claim 1, wherein: the FRP pipe is made of any material of carbon fiber, glass fiber and aramid fiber.
5. The high-strength concrete composite column with the high-strength steel pipes and the internally-arranged FRP pipes as claimed in claim 1, wherein: the high-strength steel pipe is a high-strength square steel pipe.
6. The high-strength concrete composite column with the high-strength steel pipes and the internally-arranged FRP pipes as claimed in claim 1, wherein: the high-strength steel pipe is made of steel with the strength grade of Q690 or above.
7. The high-strength concrete composite column with the high-strength steel pipes and the internally-arranged FRP pipes as claimed in claim 1, wherein: the high-strength concrete core column and the high-strength concrete layer are made of concrete with the concrete strength grade of C50 or above.
8. The high-strength concrete composite column with the high-strength steel pipes and the internally-arranged FRP pipes as claimed in any one of claims 1 to 7, wherein: the high-strength concrete core column is made of any one of construction waste concrete, recycled aggregate concrete and seawater sea sand concrete.
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CN202110013845.4A CN112726959A (en) | 2021-01-06 | 2021-01-06 | High-strength concrete composite column with high-strength steel pipes and internally-arranged FRP pipes |
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CN202110013845.4A CN112726959A (en) | 2021-01-06 | 2021-01-06 | High-strength concrete composite column with high-strength steel pipes and internally-arranged FRP pipes |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN117947911A (en) * | 2024-03-08 | 2024-04-30 | 北京市建筑设计研究院股份有限公司 | Composite pipe confined concrete core column non-node area connection structure and construction method |
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US5599599A (en) * | 1995-07-06 | 1997-02-04 | University Of Central Florida | Fiber reinforced plastic ("FRP")-concrete composite structural members |
CN104005567A (en) * | 2014-05-07 | 2014-08-27 | 北京工业大学 | Ultra-high-performance concrete reinforced concrete column with fiber reinforced polymers wound around steel pipe |
CN104594186A (en) * | 2015-01-27 | 2015-05-06 | 清华大学 | Concrete structure reinforced by round FRP (fiber-reinforced plastic) confined concrete cores |
CN105064613A (en) * | 2015-09-06 | 2015-11-18 | 南京工业大学 | Built-in FRP local restraint concrete composite member |
US20160130813A1 (en) * | 2014-11-12 | 2016-05-12 | King Saud University | Fiber reinforced composite system for strengthening of wall-like rc columns and methods for preparing such system |
CN206707122U (en) * | 2017-03-10 | 2017-12-05 | 哈尔滨工业大学深圳研究生院 | A kind of concrete filled steel tube component of the steel tube confinement of sandwich |
CN110714577A (en) * | 2019-11-08 | 2020-01-21 | 南京林业大学 | Steel pipe concrete structure with built-in composite pipe seawater sea sand concrete |
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2021
- 2021-01-06 CN CN202110013845.4A patent/CN112726959A/en active Pending
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5599599A (en) * | 1995-07-06 | 1997-02-04 | University Of Central Florida | Fiber reinforced plastic ("FRP")-concrete composite structural members |
CN104005567A (en) * | 2014-05-07 | 2014-08-27 | 北京工业大学 | Ultra-high-performance concrete reinforced concrete column with fiber reinforced polymers wound around steel pipe |
US20160130813A1 (en) * | 2014-11-12 | 2016-05-12 | King Saud University | Fiber reinforced composite system for strengthening of wall-like rc columns and methods for preparing such system |
CN104594186A (en) * | 2015-01-27 | 2015-05-06 | 清华大学 | Concrete structure reinforced by round FRP (fiber-reinforced plastic) confined concrete cores |
CN105064613A (en) * | 2015-09-06 | 2015-11-18 | 南京工业大学 | Built-in FRP local restraint concrete composite member |
CN206707122U (en) * | 2017-03-10 | 2017-12-05 | 哈尔滨工业大学深圳研究生院 | A kind of concrete filled steel tube component of the steel tube confinement of sandwich |
CN110714577A (en) * | 2019-11-08 | 2020-01-21 | 南京林业大学 | Steel pipe concrete structure with built-in composite pipe seawater sea sand concrete |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN117947911A (en) * | 2024-03-08 | 2024-04-30 | 北京市建筑设计研究院股份有限公司 | Composite pipe confined concrete core column non-node area connection structure and construction method |
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Application publication date: 20210430 |