CN215829810U

CN215829810U - Concrete narrow beam reinforced by FRP (fiber reinforced Plastic) composite technology

Info

Publication number: CN215829810U
Application number: CN202121829693.7U
Authority: CN
Inventors: 毛琳; 朱泽文; 代力; 张恺; 艾志勇
Original assignee: Jiangxi Academy Of Transportation Sciences Co ltd
Current assignee: Jiangxi Transportation Bridge Inspection Reinforcement Co ltd
Priority date: 2021-08-06
Filing date: 2021-08-06
Publication date: 2022-02-15
Anticipated expiration: 2031-08-06

Abstract

The utility model discloses a narrow concrete beam reinforced by adopting an FRP (fiber reinforced Plastic) composite technology, wherein a plurality of horizontal through holes in the longitudinal direction are arranged at the upper part of a concrete beam body, a groove is formed on the surface of the beam body above the horizontal through holes, and the horizontal through holes form an upper annular closed groove, and a groove is formed on the surface of the beam body below the horizontal through holes, and the horizontal through holes form a lower annular closed groove; a plurality of transverse grooves are respectively formed in the front surface and the rear surface of the lower part of the concrete beam body; an upper closed annular FRP hoop is arranged in the upper annular closed groove, a lower closed annular FRP hoop is arranged in the lower annular closed groove, and a transverse FRP inner embedded strip is arranged in the transverse groove; and epoxy resin is filled in the horizontal through hole, the upper annular closed groove, the lower annular closed groove and the transverse groove. The reinforced structure can effectively improve the bending, shearing and twisting coupling mechanical properties of the reinforced concrete narrow beam on the premise of not changing the cross section area, and overcomes the defects that the cross section size needs to be increased and the single mechanical property of bending or shearing only can be improved in the conventional concrete structure reinforcement.

Description

Concrete narrow beam reinforced by FRP (fiber reinforced Plastic) composite technology

Technical Field

The utility model belongs to the technical field of civil engineering concrete structure reinforcement, and particularly relates to a concrete narrow beam reinforced by adopting an FRP composite technology.

Technical Field

Due to the influence of self materials and environmental factors, after a concrete structure is in service for a certain period of time, the durability, the safety and the applicability of the concrete structure are reduced to different degrees, mainly expressed as the reduction of the rigidity and the bearing capacity of a beam body, and in order to ensure the good service performance of the concrete structure, the concrete structure needs to be reinforced to prolong the service life. For example, in the field of construction and transportation, for concrete rectangular section narrow beams such as a workshop overhead traveling crane track beam, a monorail traffic track beam and the like, special purposes and load action modes of the concrete rectangular section narrow beams need to be considered, and a proper method is selected for reinforcing the concrete rectangular section narrow beams.

Currently, the reinforcing method for concrete beams mainly includes a section enlarging method, a steel wrapping method, a prestress reinforcing method, a steel plate pasting reinforcing method, a fiber material reinforcing method and the like. The fiber material reinforcing method can greatly improve the bearing capacity of the structure and increase the rigidity of the beam, and is widely applied due to the advantages of light weight, high tensile strength, strong corrosion resistance, strong material bonding force, strong magnetic wave permeability, basically no increase of the self weight and the cross-sectional area of the structure after reinforcement, and the like.

The fiber reinforcement technology adopts an external adhesion reinforcement method (EB technology) and an embedding method (NSM technology) mostly, the former is widely applied due to simple construction and easy installation, and the latter FRP material is embedded in a concrete surface layer groove, so that the contact surface between the FRP material and the concrete is increased, the bonding property between the FRP and the concrete can be effectively improved, and in addition, the method can not increase the section size. However, neither technique provides for effective exertion of the FRP tensile strength due to the lack of an end anchoring system.

The FRP reinforcement technology mainly focuses on improving the bending resistance or the shearing resistance of the concrete beam, but because the torque of the concrete narrow beam is obviously increased under the action of eccentric or lateral force couple load, the bending torsion, shearing torsion or bending-shearing torsion coupling damage is easy to occur. Therefore, aiming at the special load action of the narrow beam, the inventor provides a method for reinforcing the concrete narrow beam by bending, shearing and twisting composite stress on the basis of summarizing and analyzing the existing reinforcing technology and method, namely the concrete narrow beam is reinforced by adopting the mixed technology of Side embedded (Side Near Surface Mounted) FRP and annular closed FRP, so as to improve the bending, shearing and twisting composite stress performance of the concrete narrow beam.

Disclosure of Invention

Based on the technical background, the utility model provides the concrete narrow beam reinforced by the FRP composite technology, and aims at the characteristics that the section form and the coupling stress of the concrete narrow beam reinforcement are not changed, the composite reinforcement technology combining the longitudinal surface embedded FRP and the annular surface embedded FRP is adopted to reinforce the concrete narrow beam.

In order to achieve the technical purpose, the technical scheme adopted by the utility model is as follows.

The utility model provides an adopt reinforced (rfd) concrete narrow beam of FRP composite technology which characterized in that: the upper part of the concrete beam body is provided with a plurality of horizontal through holes in the longitudinal direction, the surface of the beam body above the horizontal through holes is provided with a groove and the horizontal through holes form an upper annular closed groove, and the surface of the beam body below the horizontal through holes is provided with a groove and the horizontal through holes form a lower annular closed groove; a plurality of transverse grooves are respectively formed in the front surface and the rear surface of the lower part of the concrete beam body; an upper closed annular FRP hoop is arranged in the upper annular closed groove, a lower closed annular FRP hoop is arranged in the lower annular closed groove, the upper closed annular FRP hoop and the lower closed annular FRP hoop are bonded into a whole through vertical upper and lower annular FRP bonding strips, and a transverse FRP inner fillet is arranged in each transverse groove; the horizontal through hole, the upper annular closed groove, the lower annular closed groove and the transverse groove are filled with epoxy resin, and the outer surfaces of the upper closed annular FRP hoop, the lower closed annular FRP hoop, the upper and lower FRP bonding strips and the transverse FRP embedded strip are coated with epoxy resin with a certain thickness.

Furthermore, the coating thickness of the epoxy resin is 2-5 mm.

Furthermore, the horizontal through hole is formed in the height range of the beam body from 1/3-1/5 of the top of the beam body 1.

Furthermore, the transverse groove is formed in the height range of the beam body from 1/3-1/5 of the bottom of the beam body 1.

Furthermore, the lap joints of the upper closed annular FRP hoop and the lower closed annular FRP hoop which are respectively self-closed into a ring are arranged in the horizontal through hole, and the length of the lap joint is greater than 1/2 of the width of the beam body.

Further, the vertical spacing distance between the upper closed annular FRP hoop and the lower closed annular FRP hoop is not less than 200 mm.

The utility model has the beneficial effects that: compared with the prior art, the utility model adopts the structure of combining the transverse embedded FRP and the longitudinal annular closed FRP at the bottoms of the two sides of the beam to reinforce the concrete narrow beam, and has the following beneficial effects in three aspects: firstly, the annular closed FRP can effectively anchor the transverse FRP, prevent the FRP from being stressed and bursting out to a certain extent, and improve the utilization efficiency of the FRP; the annular closed FRP can play a role in shearing and twisting, the transverse FRP plays a role in bending resistance, and the combination of the annular closed FRP and the transverse FRP can improve the bending, shearing and twisting coupling mechanical properties of the concrete narrow beam; thirdly, the reinforced structure can not change the section form of the reinforced beam body, and the defects that the section size needs to be increased and the single mechanical performance of bending or shearing can only be improved in the conventional concrete structure reinforcement are overcome.

Drawings

FIG. 1 is a schematic view of the beam body opening and grooving position of the present invention.

Fig. 2 is a schematic structural diagram of the present invention.

Fig. 3 is a sectional view a-a of fig. 2.

In the figure, 1 is a beam body, 11 is a horizontal through hole, 12 is an upper annular closed groove, 13 is a lower annular closed groove, 14 is a transverse groove, 2 is epoxy resin, 3 is an upper closed annular FRP hoop, 4 is a lower closed annular FRP hoop, 5 is an upper and lower annular FRP bonding strip, and 6 is a transverse FRP inner insertion strip.

Detailed Description

The technical solution of the present invention is further described below with reference to the specific examples and the accompanying drawings.

As shown in fig. 3, a concrete narrow beam reinforced by FRP composite technology, a plurality of horizontal through holes 11 in the longitudinal direction are arranged at the upper part of a concrete beam body 1 and at a position which is apart from 1/4 the top of the beam body 1, a groove is formed on the surface of the beam body 1 above each horizontal through hole 11 and the horizontal through holes 11 form an upper annular closed groove 12, and a groove is formed on the surface of the beam body 1 below each horizontal through hole 11 and the horizontal through holes 11 form a lower annular closed groove 13; 2 transverse grooves 14 are respectively arranged at the front and rear surfaces of the lower part of the concrete beam body 1 and the height position of the beam body from 1/4 at the bottom of the beam body 1; an upper closed annular FRP hoop 3 is arranged in the upper annular closed groove 12, a lower closed annular FRP hoop 4 is arranged in the lower annular closed groove 13, the upper closed annular FRP hoop 3 and the lower closed annular FRP hoop 4 are bonded into a whole through vertical upper and lower annular FRP bonding strips 5, and a transverse FRP embedded strip 6 is arranged in each transverse groove 14; the horizontal through hole 11, the upper annular closed groove 12, the lower annular closed groove 13 and the transverse groove 14 are filled with epoxy resin 2, and the outer surfaces of the upper closed annular FRP hoop 3, the lower closed annular FRP hoop 4, the upper and lower annular FRP bonding strips 5 and the transverse FRP inner insertion strip 6 are coated with the epoxy resin 2 with the thickness of 2-5 mm.

The lap joints of the upper closed annular FRP hoop 3 and the lower closed annular FRP hoop 4 which are respectively self-closed into a ring are arranged in the horizontal through hole 11, and the lap joint length is greater than 1/2 of the width of the beam body 1.

The vertical spacing distance between the upper closed annular FRP hoop 3 and the lower closed annular FRP hoop 4 is not less than 200 mm.

The concrete narrow beam reinforced by the FRP composite technology comprises the following specific manufacturing method:

(1) according to the calculation requirement of reinforcement design, a plurality of horizontal through holes 11 are drilled in the concrete narrow beam along the longitudinal direction, the width of the hole diameter is 2-3 mm larger than the FRP width, and the height of the hole diameter needs to ensure that the upper closed annular FRP hoop 3 and the lower closed annular FRP hoop 4 are superposed in the same vertical plane in the hole and are spaced by 200 mm. A transverse groove 14 is formed in the 1/4 beam height range or the bottom of the beam at the lower part of the two sides of the beam body 1, the groove depth is smaller than the thickness of the concrete protective layer, and the groove width ensures that the thickness of the epoxy resin glue on the upper part and the lower part of the FRP is 2-5 mm.

(2) The FRP is scrubbed clean by acetone, the hole wall and the groove wall are roughened, dust and impurities are removed, and the FRP is cleaned by acetone.

(3) And epoxy resin glue is poured into the transverse groove 14 to about the groove depth 1/2, the transverse FRP embedded strip 6 is placed at the middle line of the groove, the groove bottom is lightly pressed, then the epoxy resin glue at the edge of the groove opening is filled and cleaned, and the surface is smoothed.

(4) Epoxy resin is poured into the horizontal through hole 11 and the annular groove to the groove depth 1/2, and the FRP is embedded and closed to form an upper closed annular hoop and a lower closed annular hoop. The lapping length of the annular FRP is not less than 1/2 of the beam width, the lapping joint is positioned in the horizontal through hole 11, the joint is tightly pasted up and down, the longitudinal distance between the upper closed annular FRP hoop and the lower closed annular FRP hoop is determined according to a design scheme, but the minimum distance is not less than 200 mm.

(5) And an upper ring FRP bonding strip 5 and a lower ring FRP bonding strip 5 with certain lengths are bonded on two sides of the horizontal through hole 11 along the height of the beam, so that the upper closed ring hoop and the lower closed ring hoop form a stressed whole.

(6) And curing until the epoxy resin 2 in the transverse grooves 14, the horizontal through holes 11 and the annular grooves is completely cured, namely forming a reliable reinforcing effect.

The above-mentioned embodiments are illustrative of the objects, technical solutions and advantages of the present invention, and it should be emphasized that the above-mentioned embodiments are only examples of the present invention and should not be used to limit the scope of the present invention. Any modification, equivalent replacement or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides an adopt reinforced (rfd) concrete narrow beam of FRP composite technology which characterized in that: the upper part of the concrete beam body is provided with a plurality of horizontal through holes in the longitudinal direction, the surface of the beam body above the horizontal through holes is provided with a groove and the horizontal through holes form an upper annular closed groove, and the surface of the beam body below the horizontal through holes is provided with a groove and the horizontal through holes form a lower annular closed groove; a plurality of transverse grooves are respectively formed in the front surface and the rear surface of the lower part of the concrete beam body; an upper closed annular FRP hoop is arranged in the upper annular closed groove, a lower closed annular FRP hoop is arranged in the lower annular closed groove, the upper closed annular FRP hoop and the lower closed annular FRP hoop are bonded into a whole through vertical upper and lower annular FRP bonding strips, and a transverse FRP inner fillet is arranged in each transverse groove; the horizontal through hole, the upper annular closed groove, the lower annular closed groove and the transverse groove are filled with epoxy resin, and the outer surfaces of the upper closed annular FRP hoop, the lower closed annular FRP hoop, the upper and lower FRP bonding strips and the transverse FRP embedded strip are coated with epoxy resin with a certain thickness.

2. The narrow concrete beam reinforced by the FRP composite technology as claimed in claim 1, wherein: the coating thickness of the epoxy resin is 2-5 mm.

3. The narrow concrete beam reinforced by the FRP composite technology as claimed in claim 1, wherein: the horizontal through holes are formed in the height range of 1/3-1/5 away from the top of the beam body 1.

4. The narrow concrete beam reinforced by the FRP composite technology as claimed in claim 1, wherein: the transverse grooves are formed in the height range of the beam body from 1/3-1/5 of the bottom of the beam body 1.

5. The narrow concrete beam reinforced by the FRP composite technology as claimed in claim 1, wherein: the lap joints of the upper closed annular FRP hoop and the lower closed annular FRP hoop are respectively arranged in the horizontal through hole, and the length of the lap joint is greater than 1/2 of the width of the beam body.

6. The narrow concrete beam reinforced by the FRP composite technology as claimed in claim 1, wherein: the vertical spacing distance between the upper closed annular FRP hoop and the lower closed annular FRP hoop is not less than 200 mm.