CN109235924B - Double-rod early warning device of prestressed FRP (fiber reinforced Plastic) reinforced structure and ductility regulation and control method - Google Patents

Double-rod early warning device of prestressed FRP (fiber reinforced Plastic) reinforced structure and ductility regulation and control method Download PDF

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Publication number
CN109235924B
CN109235924B CN201811283915.2A CN201811283915A CN109235924B CN 109235924 B CN109235924 B CN 109235924B CN 201811283915 A CN201811283915 A CN 201811283915A CN 109235924 B CN109235924 B CN 109235924B
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plate
self
tensioning
frp
locking
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CN109235924A (en
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周英武
王小威
隋莉莉
邢锋
黄振宇
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Shenzhen University
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Shenzhen University
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Publication of CN109235924A publication Critical patent/CN109235924A/en
Priority to PCT/CN2019/083983 priority patent/WO2020087887A1/en
Priority to US16/626,000 priority patent/US11186991B2/en
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    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04G—SCAFFOLDING; FORMS; SHUTTERING; BUILDING IMPLEMENTS OR AIDS, OR THEIR USE; HANDLING BUILDING MATERIALS ON THE SITE; REPAIRING, BREAKING-UP OR OTHER WORK ON EXISTING BUILDINGS
    • E04G23/00—Working measures on existing buildings
    • E04G23/02—Repairing, e.g. filling cracks; Restoring; Altering; Enlarging
    • E04G23/0218—Increasing or restoring the load-bearing capacity of building construction elements

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  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Mechanical Engineering (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Reinforcement Elements For Buildings (AREA)

Abstract

The invention discloses a double-rod early warning device of a prestressed FRP (fiber reinforced plastic) reinforced structure and a ductility regulation and control method, wherein the double-rod early warning device comprises a fixed plate, an FRP strip, a self-locking plate, an anchoring plate, a tensioning plate, tensioning screws, nuts and expansion bolts, two ends of the FRP strip are respectively fixedly connected with the fixed plate and the self-locking plate, the tensioning screws comprise a first tensioning screw and a second tensioning screw which are arranged in parallel, the tensioning screws generate larger plastic deformation when the structure is overloaded, the structural safety early warning function is realized, the tensioning screws penetrate through the self-locking plate, the anchoring plate and the tensioning plate, the nuts are in threaded connection with the screws, the nuts are used for locking two sides of the self-locking plate, the anchoring plate and the tensioning plate, the expansion bolts are used for fixing the fixed plate, the self-locking plate and the anchoring plate on concrete, through holes on the self-locking plate are oblong holes, and the oblong. Compared with the prior art, the invention not only improves the ductility and the rigidity of the component, but also has the function of early warning of structural overload and increases the safety of the component.

Description

Double-rod early warning device of prestressed FRP (fiber reinforced Plastic) reinforced structure and ductility regulation and control method
Technical Field
The invention relates to the technical field of FRP reinforced concrete structures, in particular to a double-rod early warning device and a ductility regulation and control method of a prestressed FRP reinforced structure.
Background
With the development of concrete structure reinforcing technology, the excellent performance of FRP (fiber reinforced polymer/Plastic) is well known to more and more people, and FRP reinforced concrete structures are favored by more and more people.
However, there are significant disadvantages in current FRP prestressed reinforced concrete structures: (1) the ductility is poor, the bearing capacity is improved compared with that of a common concrete member, but the ductility is reduced to a certain extent, and early warning is lacked in damage; (2) the FRP is subjected to anchor releasing and sliding, when prestress is applied to the prestress fiber cloth, the carbon fiber plate and the anchorage device are easy to slide relatively, the carbon fiber is separated from the anchorage device along with the continuous increase of the stress, the prestress fails, and the required reinforcement effect cannot be achieved; (3) the tensioning and anchoring device has heavy structure, complex process, high technical requirement and high manufacturing cost, and can not be repeatedly used.
Therefore, how to provide a tensioning device and a tensioning method to solve the above-mentioned disadvantages of the FRP prestressed reinforced concrete structure in the prior art is a technical problem to be solved urgently by those skilled in the art.
Disclosure of Invention
The invention aims to provide a double-rod early warning device of a prestressed FRP reinforcing structure and a ductility regulation and control method, which solve the problems of easy-to-separate connection and brittle failure between FRP and an anchorage device while improving the bearing capacity and ductility of the reinforcing structure, and greatly improve the utilization rate and structural safety of FRP.
In order to achieve the purpose, the invention provides the following scheme:
the invention discloses a double-rod early warning device of a prestressed FRP (fiber reinforced plastic) reinforced structure, which comprises a fixed plate, an FRP strip, a self-locking plate, an anchoring plate, a tensioning plate, tensioning screws, nuts and expansion bolts, wherein the tensioning screws comprise a first tensioning screw and a second tensioning screw which are arranged in parallel, the fixed plate, the self-locking plate, the anchoring plate and the tensioning plate are sequentially arranged from left to right, one end of the FRP strip is fixedly connected with the fixed plate, the other end of the FRP strip is fixedly connected with the self-locking plate, the tensioning screws penetrate through the self-locking plate, the anchoring plate and the tensioning plate, the nuts are in threaded connection with the tensioning screws, the nuts are used for locking two sides of the self-locking plate, two sides of the anchoring plate and two sides of the tensioning plate, the expansion bolts are used for fixing the fixed plate, the self-locking plate and the anchoring plate on a concrete matrix, the through hole for installing the expansion bolt on the self-locking plate is a long circular hole, and the long circular hole is parallel to the tensioning screw rod.
Preferably, the fixing plate and the self-locking plate are both provided with two strip-shaped grooves which are parallel to each other, the strip-shaped grooves are used for the FRP strip to pass through, and two ends of the FRP strip are fixedly connected with the fixing plate and the self-locking plate through self-locking winding structures.
Preferably, the self-locking plate is T-shaped, the self-locking plate includes a connecting section and a fixing section, the fixing section is perpendicular to the connecting section and symmetrical with respect to the connecting section, the connecting section is used for connecting one end of the FRP strip, the connecting section is provided with the strip-shaped groove, and the fixing section is provided with the oblong hole.
Preferably, the center line of the FRP strip and the resultant force acting center line of the tension screw coincide.
Preferably, the length of the oblong hole is greater than twice the maximum elongation of the tensioning screw.
Preferably, the edges of the strip-shaped groove are of a smooth transition structure.
The invention also discloses a ductility regulation and control method of the prestressed FRP reinforcement structure, and the double-rod early warning device comprises the following steps:
s1, fixing the anchoring plate on the concrete matrix through an expansion bolt;
s2, fixing two ends of the FRP strip on the fixing plate and the self-locking plate respectively;
s3, selecting the diameter and the material of the tension screw according to the design level of the tension stress, enabling the tension screw to penetrate through the self-locking plate, the anchoring plate and the tension plate, locking the tension screw and the self-locking plate with a nut, and interlocking the tension screw and the tension plate with the nut;
s4, expanding the distance between the tension plate and the anchor plate, so as to stretch the tension screw rod, locking the tension screw rod and the anchor plate with a nut when the prestress is stretched to a designed level, and stopping stretching;
and S5, installing the expansion bolt on the concrete substrate through the long round hole of the self-locking plate, and keeping the expansion bolt fixed at the center of the long round hole on the self-locking plate, wherein the expansion bolt is not locked and screwed tightly.
Preferably, in step S2, the two ends of the FRP strip are fixed to the fixing plate and the self-locking plate by self-locking winding, respectively.
Preferably, in step S4, the distance between the tension plate and the anchor plate is enlarged by a hydraulic jack.
Preferably, in step S4, the third tensioning screw is threaded through the tensioning plate and is locked to the tensioning plate by a nut, and the distance between the tensioning plate and the anchoring plate is enlarged by stretching an end of the third tensioning screw away from the anchoring plate.
Compared with the prior art, the invention has the following technical effects:
(1) the tensioning device has the advantages of simple structure, clear construction process, low technical requirement, low manufacturing cost and convenient construction, and is suitable for construction on the engineering site;
(2) the ductility of the prestressed reinforced concrete structure can be obviously improved, and the problem of looseness between the FRP strip and the clamp is solved;
(3) the utilization rate of the FRP strip and the reliability of the reinforcing device are improved, FRP materials are saved, and the cost is saved for the reinforcing engineering;
(4) the self-warning function of structural overload is realized through the elastic-plastic deformation of the tension screw;
(5) the whole structure is easy to process and produce, can meet the requirement of industrialized production, and is convenient to popularize and apply in the field of engineering reinforcement in a large area;
(6) and the double rods are used for tensioning, so that the overall stability is better, and the loading process is more stable.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a top view of a connection mode of one end of a fixing plate of the double-rod warning device according to the present invention;
FIG. 2 is a side view of the connection mode of one end of the fixing plate of the double-rod warning device of the present invention;
FIG. 3 is a top view of the connection mode of one end of the anchoring plate of the dual-rod warning device of the present invention;
FIG. 4 is a side view of the connection mode of one end of the anchoring plate of the dual-rod warning device of the present invention;
FIG. 5 is a top view of the dual pole warning device of the present invention;
FIG. 6 is a side view of the dual pole warning device of the present invention;
FIG. 7 is a top view of the dual pole warning device of the present invention after modification;
FIG. 8 is a side view of the dual beam early warning device of the present invention after modification;
FIG. 9 is a schematic view of the fixing manner of the FRP strip at one end of the fixing plate;
FIG. 10 is a simplified schematic of FIG. 9;
FIG. 11 is a schematic view of a prestressed tension anchoring load slip curve;
FIG. 12 is a schematic cross-sectional view of a beam for an improved installation method;
FIG. 13 is a stress-strain curve of an FRP strip and a tension screw;
description of reference numerals: 1, fixing a plate; 2FRP strips; 3 self-locking plate; 4, anchoring a plate; 5, stretching a plate; 6, a first tensile screw rod; 7 a second tensioning screw; 8, a third tensioning screw; 9, a nut; 10 expansion bolts; 11 hydraulic jack.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention aims to provide a double-rod early warning device of a prestressed FRP reinforcing structure and a ductility regulation and control method, which solve the problems of easy-to-separate connection and brittle failure between FRP and an anchorage device while improving the bearing capacity and ductility of the reinforcing structure, and greatly improve the utilization rate and structural safety of FRP.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
As shown in fig. 1 to 13, the present embodiment provides a double-rod warning device for a prestressed FRP reinforced structure, which includes a fixing plate 1, an FRP strip 2, a self-locking plate 3, an anchoring plate 4, a tensioning plate 5, tensioning screws, nuts 9, and expansion bolts 10, where the tensioning screws include a first tensioning screw 6 and a second tensioning screw 7 that are arranged in parallel at the same height. Wherein, fixed plate 1, self-locking plate 3 and anchor board 4 are low carbon steel structure, FRP strip 2 is used for connecting fixed plate 1 and self-locking plate 3, the stretch-draw screw rod is used for connecting self-locking plate 3, anchor board 4 and stretch-draw board 5, nut 9 and stretch-draw screw rod threaded connection, nut 9 is used for locking the stretch-draw screw rod respectively with self-locking plate 3, anchor board 4 and stretch-draw board 5 each other, expansion bolts 10 are used for being fixed in on the concrete base member with fixed plate 1, self-locking plate 3 and anchor board 4.
Fixed plate 1, self-locking plate 3, anchor board 4 and stretch-draw board 5 set gradually from left to right, the one end and the fixed plate 1 fixed connection of FRP strip 2, the other end and the self-locking plate 3 fixed connection of FRP strip 2. The tensioning screws penetrate through the self-locking plate 3, the anchoring plate 4 and the tensioning plate 5, and the nuts 9 are used for being locked on two sides of the self-locking plate 3, two sides of the anchoring plate 4 and two sides of the tensioning plate 5. The through hole for installing the expansion bolt 10 on the self-locking plate 3 is a long circular hole, and the long circular hole is arranged in parallel with the tensioning screw. The length of the oblong hole is more than twice of the maximum elongation of the tension screw, and the purpose is to fully exert the deformation of the tension screw so as to fully utilize the elongation of the tension screw to improve the ductility of the whole member.
The end fixing mode of FRP strip 2 has the multiple, and in this embodiment, all be provided with two bar grooves that are parallel to each other on fixed plate 1 and the auto-lock plate 3, the bar groove is used for supplying FRP strip 2 to pass, and FRP strip 2's both ends are through from locking-type winding structure and fixed plate 1 and auto-lock plate 3 fixed connection. The strip-shaped groove is subjected to smoothing treatment, so that the FRP strip 2 is prevented from being cut off due to stress concentration when being wound. As shown in fig. 9 to 10, arrows indicate the tendency of the FRP strip 2 to slide when it is stretched by an external force. FRP strip 2 tensile force T under external force0The FRP strip 2 will be pulled out if there is no friction between the respective contact surfaces, which will generate a tendency of movement as indicated by the arrows in the figure. Due to the friction resistance between the inner and outer FRP strips 2 and between the FRP strips 2 and the steel plate, the self-locking of the winding rod can be generated.
Before the two ends of the FRP strip 2 are wound on the fixing plate 1 and the self-locking plate 3, structural glue can be coated at the positions of the long round holes on the fixing plate 1 and the self-locking plate 3 and the FRP strip 2, and the structural glue mainly considers that the FRP strip 2 has large width and small thickness, generates eccentric stress in the installation and assembly processes, easily causes the damage to the large side of stress, and the damage to the small side. After the structural adhesive is coated, all the fiber yarns between the FRP strips 2 are connected into a whole and stressed uniformly. The FRP strips 2 are adhered according to the winding direction of fig. 9-10, and the connecting position of the FRP strips 2 can be properly adjusted to achieve a good connecting position before the structural adhesive is hardened, thereby preventing adverse effects such as eccentricity. Along with the increase of FRP strip 2 winding thickness, connectivity can improve gradually to solve the loose problem of FRP strip 2 connection, reach the good effect that improves and consolidate the bearing capacity. The FRP strips 2 and the concrete matrix can be in a form of bonding or non-bonding, and those skilled in the art can select the FRP strips according to actual needs.
For the convenience of being connected with FRP strip 2, from locking plate 3 is the T shape, and from locking plate 3 includes linkage segment and canned paragraph, and the canned paragraph perpendicular to linkage segment just is symmetrical about the linkage segment, and the linkage segment is used for connecting FRP strip 2's one end, is provided with the bar groove on the linkage segment, is provided with the slotted hole on the canned paragraph.
In order to make the whole structure more stable, the horizontal distance from the center line of the FRP strip 2 to the first tension screw 6 is equal to the horizontal distance from the center line of the FRP strip 2 to the second tension screw 7, the FRP strip 2 and the tension screws are approximately positioned at the same height, and the center line of the FRP strip 2 and the resultant action center line of the tension screws are superposed. In fig. 6, the FRP strips 2 and the tension screws are installed in a manner of being adhered to the concrete matrix, which is not preferable. The cross section schematic diagram of the improved installation method beam is shown in fig. 8 and 12, the FRP strips 2 and the tension screws are preferably a certain height (Δ h) away from the concrete matrix, and with the increase of Δ h, the height of the calculated section can be increased, so that the inertia moment of the section is increased, and the bending rigidity is improved, specifically as follows:
obtaining a prestressed carbon fiber flexural member according to the concrete structure reinforcement design specification (GB 50367-2013):
(1) a flexural member with no crack:
Bs＝0.85EcI0
(2) a flexural member with cracks:
note that: b issFor flexural rigidity, I0Is the moment of inertia.
So bending rigidity BsAll follow the section moment of inertia (I)0) The increase in (c) is an increase. I is0Moment of inertia of unreinforced beam cross section, I1To improve the mounting method the moment of inertia of the cross section of the rear beam, Δ I is the increased moment of inertia. As can be seen from the above equation, Δ I increases with increasing Δ h, so this mounting scheme increases Δ I by increasing Δ h and increases Δ I by increasing Bs。
The embodiment also provides a ductility regulation and control method of the prestressed FRP reinforcement structure, and the method comprises the following specific steps of:
s1, fixing the anchor plate 4 on the concrete matrix through the expansion bolts 10;
s2, fixing the two ends of the FRP strip 2 on the fixing plate 1 and the self-locking plate 3 respectively;
s3, selecting the diameter and the material of a tension screw according to the design level of tension stress, enabling the tension screw to penetrate through the self-locking plate 3, the anchoring plate 4 and the tension plate 5, locking the tension screw and the self-locking plate 3 with a nut 9, and locking the tension screw and the tension plate 5 with the nut 9;
s4, expanding the distance between the tension plate 5 and the anchoring plate 4, so as to stretch the tension screw, locking the tension screw and the anchoring plate 4 with a nut 9 when the prestress is stretched to a designed level, and stopping stretching;
and S5, fixing the self-locking plate 3 on the concrete base body by using the expansion bolt 10, and fixing the expansion bolt 10 at the center of the long round hole on the self-locking plate 3, wherein the expansion bolt 10 is not locked and screwed tightly.
Steps S1 to S5 are a prestress design process, and after the prestress design is completed, the obtained double-rod warning device can be used for component loading. In the prestress design, the tension process of step S4 does not cause the tension screw to be broken, and the tension screw is broken only during the component loading process.
In order to improve the ductility of the structure and realize the self-warning function of the structure, the tension screw rod should be made of a material with elastic-plastic deformation capacity (figure 13), and the elastic modulus (E) of the tension screw rod is required2An elastic modulus (E) of FRP or more1) And the amount of fracture deformation (ε)uSee FIG. 13) and amount of plastic deformation (. epsilon.)ySee FIG. 13) is εu/εyThe ductility requirements of the structure should be met.
The tensioning screw has the same early warning function as a fuse in the using process, has the replaceable and restorable functions, and can early warn the whole prestress reinforcing process by detecting the elongation of the tensioning screw; because the tensioning screw is made of plastic materials, when the tensioning screw is tensioned to a certain level, the bearing load is almost unchanged, the deformation of the tensioning screw is continuously increased, and the deformation reaches a certain degree, namely the tensioning screw is considered to be failed, and the tensioning screw can be replaced and prestressed reinforcement can be carried out again.
In step S2, the FRP strip 2 is preferably fixed to the fixing plate 1 and the self-locking plate 3 by self-locking winding for improving the connection manner of the FRP strip 2 and the reliability of the connection, and the specific winding structure is shown in fig. 9-10.
In step S5, the length of the oblong hole is Δ L1+△L2Wherein Δ L1Is the distance between the expansion bolt 10 and the left end of the oblong hole, DeltaL2The distance between the expansion bolt 10 and the right end of the oblong hole.DeltaL following the movement of the self-locking plate 31And Δ L2Is constantly changing in size, and the length and the sum of the values are constant. When the expansion bolt 10 passes through the middle point of the long round hole of the self-locking plate 3 and is fixed on the concrete substrate, the delta L is1＝△L2. When the tension screw 5 is broken, the self-locking plate 3 will gradually move leftwards until the expansion bolt 10 is moved to the position, namely the delta L on the right side of the expansion bolt 102Becomes 0. And then the nut 9 of the expansion bolt 10 is screwed, at the moment, the expansion bolt 10 plays a role of fixing the self-locking section, the prestress reinforcement can be converted into non-prestress reinforcement, the structure is still in a safe state, and the ductility control of the member is realized.
As shown in fig. 5 to 6, the distance between the tensioning plate 5 and the anchoring plate 4 can be enlarged by the hydraulic jack 11, so as to stretch the tensioning screw; as shown in fig. 7 to 8, the third tensioning screw 8 may pass through the tensioning plate 5, the nut 9 may be used to lock the third tensioning screw 8 and the tensioning plate 5 to each other, and the distance between the tensioning plate 5 and the anchoring plate 4 may be expanded by stretching one end of the third tensioning screw 8 away from the anchoring plate 4, thereby achieving stretching of the tensioning screw.
The length of the long round hole is two times larger than the maximum elongation of the tensioning screw, so that the sliding displacement of the self-locking section of the tensioning end is larger than the elongation of the fuse, and the elongation of the tensioning screw is fully utilized to improve the ductility of the whole member.
The prestress tension anchoring load sliding curve is shown in figure 11, Pu3Is the bearing force after the application of prestress, Pu2The self-locking section of the tensioning end after the prestress is unloaded is the bearing capacity after the self-locking section of the tensioning end is anchored by the expansion bolt 10, and the self-locking section of the tensioning end can also be considered to reinforce the end part of the FRP. Pu1Is the bearing force of the non-prestressed member, DeltaP1Is the portion where the prestress is increased, Δ P2Is the load-bearing capacity, DeltaL, of the carbon-fibre-reinforced component after the prestressing has been unloaded3Is the elongation of the tension screw. As can be seen from fig. 11, the stretching device and the stretching method provided by the present embodiment can significantly improve the ductility of the prestressed structure, and implement a controllable ductility design. Prestress reinforcement when tension screw rod failsAnd the structure is converted into a non-prestressed reinforcement and still in a safe state. It should be noted that, in the conventional prestressed reinforcement, ductility is sacrificed to improve the early-stage rigidity of the component, and this embodiment not only improves the early-stage rigidity of the component, but also improves the ductility of the component, and increases the safety of the component.
In this embodiment, the tension screw is a cylindrical threaded rod cast by a ductile material, the deformation of the tension screw is a key of overall ductility control, and the material, the diameter and the shape of the tension screw can be designed according to the actual reinforcement engineering condition to meet the requirements of different types of reinforcement engineering. The material of the stretching threaded rod is preferably shape memory alloy, the shape memory alloy has the advantage of fatigue resistance, and the shape memory alloy is characterized in that after plastic deformation occurs, the shape before deformation can be recovered through a proper thermal process. Therefore, the tensioning screw rod in the embodiment can be restored by heating, and can be replaced after being broken, and the use of the whole tensioning structure is not influenced.
The principle and the implementation mode of the present invention are explained by applying specific examples in the present specification, and the above descriptions of the examples are only used to help understanding the method and the core idea of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.

Claims (10)

1. The double-rod early warning device of the prestressed FRP reinforcement structure is characterized by comprising a fixing plate, an FRP strip, a self-locking plate, an anchoring plate, a tensioning plate, tensioning screws, nuts and expansion bolts, wherein the tensioning screws comprise a first tensioning screw and a second tensioning screw which are arranged in parallel, the fixing plate, the self-locking plate, the anchoring plate and the tensioning plate are sequentially arranged from left to right, one end of the FRP strip is fixedly connected with the fixing plate, the other end of the FRP strip is fixedly connected with the self-locking plate, the tensioning screws penetrate through the self-locking plate, the anchoring plate and the tensioning plate, the nuts are in multiple threaded connection with the tensioning screws, the nuts are used for being locked on two sides of the self-locking plate, two sides of the anchoring plate and two sides of the tensioning plate, the expansion bolts are used for fixing the fixing plate, the self-locking plate and the anchoring plate on a concrete matrix, the through hole for installing the expansion bolt on the self-locking plate is a long circular hole, and the long circular hole is parallel to the tensioning screw rod.
2. The double-rod prewarning device for prestressed FRP reinforcement structures as recited in claim 1, wherein the fixing plate and the self-locking plate are each provided with two strip grooves parallel to each other, the strip grooves are used for the FRP strip to pass through, and two ends of the FRP strip are fixedly connected with the fixing plate and the self-locking plate through self-locking winding structures.
3. The double-rod early warning device for the prestressed FRP reinforcement structure of claim 2, wherein the self-locking plate is T-shaped, the self-locking plate comprises a connecting section and a fixing section, the fixing section is perpendicular to the connecting section and symmetrical with respect to the connecting section, the connecting section is used for connecting one end of the FRP strip, the connecting section is provided with the strip-shaped groove, and the fixing section is provided with the oblong hole.
4. The double-rod warning device for the prestressed FRP reinforcement structure of claim 1, wherein the centerline of the FRP strip and the resultant force action centerline of the tension screw coincide.
5. The double-rod warning device for the prestressed FRP reinforcing structure of claim 1, wherein the length of the oblong hole is more than twice the maximum elongation of the tension screw.
6. The double-rod early warning device for the prestressed FRP reinforcing structure of claim 2, wherein the edges of the strip-shaped groove are in a smooth transition structure.
7. A ductility regulation and control method for a prestressed FRP reinforcement structure, which is characterized in that the double-rod early warning device of claim 1 is used, and comprises the following steps:
s1, fixing the anchoring plate on the concrete matrix through an expansion bolt;
s2, fixing two ends of the FRP strip on the fixing plate and the self-locking plate respectively;
s3, selecting the diameter and the material of the tension screw according to the design level of the tension stress, enabling the tension screw to penetrate through the self-locking plate, the anchoring plate and the tension plate, locking the tension screw and the self-locking plate with a nut, and interlocking the tension screw and the tension plate with the nut;
s4, expanding the distance between the tension plate and the anchor plate, so as to stretch the tension screw rod, locking the tension screw rod and the anchor plate with a nut when the prestress is stretched to a designed level, and stopping stretching;
and S5, installing the expansion bolt on the concrete substrate through the long round hole of the self-locking plate, and keeping the expansion bolt fixed at the center of the long round hole on the self-locking plate, wherein the expansion bolt is not locked and screwed tightly.
8. The ductility adjusting and controlling method for the prestressed FRP reinforcing structure of claim 7, wherein in the step S2, both ends of the FRP strip are respectively fixed on the fixing plate and the self-locking plate by self-locking winding.
9. The ductility adjusting and controlling method of the prestressed FRP reinforcing structure of claim 7, wherein in the step S4, the distance between the tension plate and the anchor plate is enlarged by a hydraulic jack.
10. The ductility adjusting and controlling method for the prestressed FRP reinforcement structure of claim 7, wherein in step S4, the third tension screw is threaded through the tension plate and is locked with the tension plate by using a nut, and the distance between the tension plate and the anchor plate is enlarged by stretching one end of the third tension screw away from the anchor plate.
CN201811283915.2A 2018-10-31 2018-10-31 Double-rod early warning device of prestressed FRP (fiber reinforced Plastic) reinforced structure and ductility regulation and control method Active CN109235924B (en)

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Application Number Priority Date Filing Date Title
CN201811283915.2A CN109235924B (en) 2018-10-31 2018-10-31 Double-rod early warning device of prestressed FRP (fiber reinforced Plastic) reinforced structure and ductility regulation and control method
PCT/CN2019/083983 WO2020087887A1 (en) 2018-10-31 2019-04-24 Early warning apparatus of pre-stressed frp reinforcing structure and ductility regulation method
US16/626,000 US11186991B2 (en) 2018-10-31 2019-04-24 Early warning device and ductility control method for prestressed FRP reinforced structure

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CN110866302B (en) * 2019-11-19 2022-11-15 河北工业大学 FRP bending-resistant reinforcement design method based on member early warning wire theory

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KR100677847B1 (en) * 2005-01-20 2007-02-02 (주)엠프로 Concrete Prestressing device and Strengthening method using thereof
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CN203320978U (en) * 2013-06-07 2013-12-04 华北水利水电大学 Tensioning and anchoring device for prestressed carbon fiber sheet reinforced long-span concrete structure
CN104895251A (en) * 2014-03-04 2015-09-09 五邑大学 Wraparound type waveform anchor for fiber sheets and pre-tensioning method thereof
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