CN106836021B - A kind of pre-stress FRP sheet material Shear Strengthening beams of concrete experimental provision - Google Patents

Abstract

The invention discloses an experimental device for shearing and strengthening concrete beams with prestressed FRP sheets. The anchoring device at the front end of the FRP sheet arranged at the bottom of the web of the concrete beam, the steel bead in the middle of the FRP sheet arranged at the middle of the web of the concrete beam, the anchoring device at the rear end of the FRP sheet arranged at the lower side of the outer end of the flange plate of the concrete beam, and the setting The limiting device and stabilizing device installed on the side of the web of the concrete beam, the jack fixed horizontally on the tensioning pedestal, the front steel plate of the tension end and the rear steel plate of the tension end located on both sides of the jack, and the front steel plate and the rear steel plate of the tension end passing through the jack. The screw rod of the steel plate behind the tension end, and the FRP sheet tension end fixture arranged at one end of the screw rod adjacent to the concrete beam. The device of the invention is simple to manufacture, fast and convenient to install, and can be pasted to the side of a concrete beam after applying prestress to the FRP sheet to play the role of shearing reinforcement.

Description

An Experimental Device for Shear Strengthening of Concrete Beams with Prestressed FRP Sheets

technical field

The invention belongs to the fields of civil engineering, construction engineering, highway engineering and municipal engineering, and relates to a prestressed FRP sheet anti-shear reinforcement concrete beam experimental device.

Background technique

Prestressed concrete T-section beams (T-beams) and prestressed concrete box-section beams (box girders) are commonly used concrete beams in building structures and bridge structures. In recent years, oblique cracks often appear in the webs of T-beams and box girders in highway bridges due to overloading, natural environment and cracking of material properties, which need to be reinforced.

The traditional strengthening methods of T girder and box girder mainly include enlarging section method, sticking steel plate method, external prestressing method, conversion system method, etc. But above-mentioned reinforcement method has following weak point: 1) can't fast repair damaged concrete beam, as the tension anchorage device of external prestressing method is complicated, and enlarging cross-section method needs to plant steel bar, supporting formwork, pouring concrete etc. 2) The steel plate is easy to corrode, which seriously affects the interface bonding performance. 3) The self-weight of the concrete beam increases greatly. In recent years, fiber reinforced polymer (Fiber Reinforced Polymer, referred to as "FRP") composite materials have the characteristics of light weight, high strength, corrosion resistance, and convenient construction. Using external FRP sheets to strengthen concrete beams has been widely used in most countries in the world. The research on various new reinforcement technologies for concrete structures developed by FRP materials has also become one of the hot spots in the field of structural engineering research. External FRP sheet reinforcement technology, that is, use adhesives (mostly epoxy resin) to paste FRP sheets on the bottom or side of concrete beams for bending and shear reinforcement of concrete beams; or wrap fiber cloth in concrete Column surfaces, used to improve the column's capacity and ductility.

Despite the aforementioned advantages, the technology of externally attaching ordinary FRP sheets to strengthen concrete structures still faces some unavoidable important problems in engineering applications: 1) The strength utilization rate of FRP sheets is low; 2) It cannot limit the development of oblique cracks in concrete beams ; 3) The stiffness of the concrete beam cannot be effectively promoted, seriously affecting the normal performance of the concrete beam. For this reason, some scholars have proposed to apply prestress to ordinary FRP sheets to form prestressed FRP sheet reinforcement technology, which can give full play to the characteristics of light weight and high strength of FRP sheets, delay component cracking, limit crack development, and effectively improve the normal use of concrete beams. performance.

In the patent document with publication number CN102425311B, a reinforcement method based on embedding prestressed FRP slats on the surface is disclosed. The method is to open a groove on the concrete structure to be reinforced, install the tensioning machine of the FRP lath and the fixture of the FRP lath, put it into the groove after stretching the FRP lath, fill it with adhesive, and wait for the adhesive to cure Finally, the tensioning device is removed to obtain prestress. Although the method for applying prestress is given in this invention patent, it does not explain how to anchor and tension the FRP slats.

In the patent document with the publication number CN102304958A, a prestressed fixture is disclosed, which is embedded with fiber lath strips on the surface to reinforce concrete structures, including a fixture outer frame, fixture bead, and jackbolts. By pushing the bolts, the fixture bead is tightly pressed against the fiber lath to play an anchoring role. The anchoring method involved in this published patent needs to make grooves in the bottom of the beam in advance, which will cause great damage to the concrete beam, and only involves the bending resistance of the concrete beam.

In the patent document with the publication number CN105178515A, a built-in anchor type prestressed FRP tendon tension anchoring device is disclosed, which includes a steel sleeve, a bonding material, a screw rod, a nut, an annular steel gasket and a circular anchor ring. The device is to insert the two ends of the FRP bars into the steel sleeves at the tensioning end and the anchoring end respectively, fix them with bonding materials, and weld a section of screw rod on the closed end of the steel sleeve at the tensioning end, so that the screw rod passes through the tensioning end. The circular anchor ring wall at the anchor end, the circular steel gasket and nut matching the screw rod are installed in the circular anchor ring, the closed end of the steel sleeve at the fixed end passes through the ring wall of the circular anchor ring at the anchor end, and is connected with the circular anchor ring. The anchor rings are welded together. The device is suitable for tension anchorage of FRP tendons and for bending reinforcement of concrete beams, and does not involve shear reinforcement of concrete beams.

In the patent document whose publication number is CN101736912B, a kind of anchoring method of external sticking of prestressed fiber cloth is disclosed. The anchoring method is as follows: use resin to bond the prestressed FRP sheet and concrete into a whole, release the prestress after the resin is heated and solidified, and take certain measures at the anchoring end of the prestressed FRP sheet at the end to release or partially release the prestressed FRP sheet. The prestressed end of the stress FRP sheet is anchored to achieve the purpose of eliminating or reducing the stress concentration at the end. This patent only involves the anchoring of the end of the prestressed FRP sheet, and does not involve a complete set of tensioning and anchoring devices for the prestressed FRP sheet.

In the patent document whose publication number is CN10173252A, a reinforcement device for prestressed FRP fabric of concrete beams is disclosed. The device is to install a shell with steel plates on three sides at the end of the FRP cloth, and slide grooves are opened on both sides of the shell. The reinforcing screw with tie rod is inserted into the chute, the FRP cloth is wound on the reinforcing screw, and the prestress is applied to the FRP cloth through the movement of the pulling rod in the chute. Although the device can prestress the FRP fabric, it does not involve the shear reinforcement of concrete beams.

In the patent document with the publication number CN105839936A, a tension anchoring device for prestressed FRP mesh is disclosed, which includes a lower lining plate, an upper pressing plate and fastening connectors. The working principle of the device is to embed the FRP grid into the lower liner with transverse and longitudinal grooves, press the upper pressing plate with the corresponding protruding ribs, and connect them with fastening connectors to anchor the FRP grid on the beam body. But this device does not involve the shear reinforcement of concrete beams.

To sum up, most of the existing public literatures involve the tensioning and anchoring devices of FRP tendons. FRP tendons and FRP sheets are completely different in geometric configuration, material, physical, mechanical properties, etc., so FRP tendons cannot be directly Advanced tensioning and anchoring devices are applied to FRP sheets. In addition, there is no experimental device involving the shear strengthening of concrete beams with prestressed FRP sheets.

Contents of the invention

Technical problem: The present invention provides an experimental device for shear-strengthening concrete beams with prestressed FRP sheets that is simple to manufacture, fast and convenient to install, and can be reused.

Technical solution: The experimental device for shear-strengthening concrete beams with prestressed FRP sheets of the present invention includes a concrete beam, a tensioning pedestal facing one side of the web of the concrete beam, and a steering wheel arranged at the junction of the flange plate and the web of the concrete beam. Device, the front end anchorage device of the FRP sheet arranged at the bottom of the concrete beam web, the steel layer in the middle of the FRP sheet arranged in the middle of the concrete beam web, and the rear end anchorage device of the FRP sheet arranged on the lower side of the outer end of the concrete beam flange , setting a limit device and a stabilizing device installed on the side of the web of the concrete beam, a jack horizontally fixed on the tensioning pedestal, the front steel plate at the tension end and the rear steel plate at the tension end located on both sides of the jack, passing through The screw rods of the steel plate before the tension end and the steel plate behind the tension end, and the FRP sheet tension end fixture arranged at the end of the screw rod adjacent to the concrete beam.

In a preferred solution of the present invention, the steering device includes an inner steering block embedded in the protective layer of the concrete beam, and an outer steering block respectively fixed to both ends of the inner steering block by bolts, and the bolts pass through the inner steering block and the outer steering block. Tighten with the nut after turning the block.

In the preferred solution of the present invention, the front-end anchoring device of the FRP sheet, the steel bead in the middle of the FRP sheet and the rear-end anchoring device of the FRP sheet have the same structure, and all include an inner backing plate embedded in the concrete beam protective layer, an outer pressing plate and An expansion bolt is tightened with a nut after passing through the inner backing plate and the outer pressure plate.

In a preferred solution of the present invention, the limiting device includes a tripod consisting of a front steel plate, an oblique support, and a bottom steel plate, and a rubber backing plate arranged outside the front steel plate for adjusting the position of the concrete beam. The device is anchored to the ground with anchor bolts at the bottom steel plate.

In a preferred solution of the present invention, the clamp at the tension end of the FRP sheet includes an upper T-shaped clip and a lower T-shaped clip connected to the upper T-shaped clip by bolts, and the upper T-shaped clip and the lower T-shaped clip The clip clamps the FRP sheet.

In a preferred solution of the present invention, the screw passes through the round holes on the upper T-shaped clip and the lower T-shaped clip, and is tightened and limited by an outer limit nut.

In a preferred solution of the present invention, the stabilizing device includes an upper lug-type anchoring device, a lower lug-type anchoring device, a diagonal rod connecting the upper lug-type anchoring device and the lower lug-type anchoring device, and is sleeved on the The connecting sleeve on the oblique rod and the anchor bolts arranged on the lower lug-type anchoring device, the two ends of the oblique rod are respectively installed and connected with the upper lug-type anchoring device and the lower lug-type anchoring device through bolts.

In a preferred solution of the present invention, the upper lug-type anchoring device and the lower lug-type anchoring device have the same structure, and both include an anchoring bottom steel plate and a lug with a round hole arranged on the anchoring bottom steel plate.

The experimental device provided by the present invention can apply prestress to the FRP sheet and paste it on the side of the concrete beam to play the role of shear reinforcement; the experimental device provided by the present invention has a wide range of applications, not only can be used for concrete beams, steel beams, and It can be applied to shear reinforcement of beams with different cross-section forms. The experimental device of the invention has convenient construction and simple operation, can effectively apply prestress to the FRP sheet, exert the high-strength characteristics of the FRP sheet, and improve the service performance of the reinforced beam.

Beneficial effect: compared with the prior art, the present invention has the following advantages:

1. Realize the shear strengthening of concrete beams with prestressed FRP sheets

In the prestressed FRP tensioning and anchoring devices disclosed in existing patent documents and related documents, there are many tensioning and anchoring devices involving prestressed FRP tendons, and the working principles of the existing FRP sheet or FRP grid tensioning and anchoring devices are the same The experimental device in the invention is completely different, and there is no open literature related to the experimental device for shearing and strengthening concrete beams with prestressed FRP sheets.

The prestressed FRP sheet anti-shear strengthening concrete experimental device designed by the present invention can be quickly installed after being processed and assembled according to the design requirements, and the FRP sheet is prestressed and anchored on the side of the beam body to realize the shear reinforcement of the concrete beam .

2. Convenient construction and reusable

In the patent document whose publication number is CN101736912B, a kind of anchoring method of external sticking of prestressed fiber cloth is disclosed. The anchoring method is as follows: use resin to bond the prestressed FRP sheet and concrete into a whole, release the prestress after the resin is heated and solidified, and take certain measures at the anchoring end of the prestressed FRP sheet at the end to release or partially release the prestressed FRP sheet. The prestressed end of the stress FRP sheet is anchored to achieve the purpose of eliminating or reducing the stress concentration at the end. This patent only involves the anchoring of the end of the prestressed FRP sheet, and does not involve a complete set of tensioning and anchoring devices for the prestressed FRP sheet.

In the patent document whose publication number is CN10173252A, a reinforcement device for prestressed FRP fabric of concrete beams is disclosed. The device is to install a shell with steel plates on three sides at the end of the FRP cloth, and slide grooves are opened on both sides of the shell. The reinforcing screw with tie rod is inserted into the chute, the FRP cloth is wound on the reinforcing screw, and the prestress is applied to the FRP cloth through the movement of the pulling rod in the chute. Although this device can apply prestress to the FRP cloth, its working principle is completely different from that of the device of the present invention.

In the patent document with the publication number CN105839936A, a tension anchoring device for prestressed FRP mesh is disclosed, which includes a lower lining plate, an upper pressing plate and fastening connectors. The working principle of the device is to embed the FRP grid into the lower liner with transverse and longitudinal grooves, press the upper pressing plate with the corresponding protruding ribs, and connect them with fastening connectors to anchor the FRP grid on the beam body. Obviously, the working principle of this device is completely different from that of the present invention.

The working principle of the FRP sheet or FRP grid tensioning and anchoring device disclosed in the above patent documents is completely different from that of the experimental device in the present invention. The prestressed FRP sheet anti-shear strengthening experimental device in the present invention is simple to manufacture, fast and convenient to install. After the construction is finished, the whole set of devices can be dismantled and reused to save materials.

3. Wide range of applications

The invention does not require special equipment, takes up less space, and saves construction costs. The invention has a wide range of applications, not only for concrete beams and steel beams, but also for shear reinforcement of concrete beams or steel beams with different cross-sectional forms (rectangular, T-shaped, box-shaped).

Description of drawings

Fig. 1 is a schematic diagram of the experimental device of the present invention, wherein Fig. 1a is a schematic diagram of a side view, Fig. 1b is a schematic diagram of a top view, and Fig. 1c is a schematic diagram of a front view;

Fig. 2 is the schematic diagram of the FRP sheet turning device in the experimental device of the present invention;

Fig. 3 is the schematic diagram of the FRP sheet front end anchoring device, the FRP sheet middle steel bead and the FRP sheet rear anchoring device in the experimental device of the present invention;

Fig. 4 is a schematic diagram of a concrete beam limiting device in the experimental device of the present invention, wherein Fig. 4a is a schematic side view, and Fig. 4b is a schematic front view;

Fig. 5 is a schematic diagram of a concrete beam stabilizing device in the experimental device of the present invention, wherein Fig. 5a is a schematic side view, and Fig. 5b is a schematic front view;

Fig. 6 is a schematic diagram of the ear type anchoring device in the experimental device of the present invention, wherein 6a is a schematic side view, and Fig. 6b is a schematic front view;

Fig. 7 is a schematic diagram of the tension end fixture of the FRP sheet in the experimental device of the present invention, wherein 7a is a schematic side view, Fig. 7b is a schematic top view, and 7c is a schematic front view.

In the figure: 1 is the concrete beam; 2 is the steering device; 3 is the front-end anchor device of the FRP sheet; 4 is the rear-end anchor device of the FRP sheet; 5 is the bead in the middle of the FRP sheet; 6 is the limit device; 7 is the stabilization device ; 8 is the anchor bolt; 9 is the FRP sheet; 10 is the tension end fixture of the FRP sheet; 11 is the screw; 12 is the front steel plate; 13 is the rear steel plate; 14 is the jack; 15 is the middle limit nut; 16 17 is a jack support; 18 is a polytetrafluoroethylene plate; 19 is a tension pedestal; 20 is an inner steering block; 21 is an outer steering block; 22 is a bolt; 23 is an inner backing plate; 24 is an outer Pressing plate; 25 is expansion bolt; 26 is front steel plate; 27 is oblique support; 28 is bottom steel plate; 29 is rubber backing plate; 30 is upper T-shaped clip; 31 is lower T-shaped clip; 34 is the upper lug-type anchoring device; 35 is the lower lug-type anchoring device; 36 is the inclined rod; 37 is the connecting sleeve; 38 is the anchor bolt; 39 is the bolt; 40 is the anchoring bottom plate ; 41 is an ear plug.

Detailed ways

The present invention will be further described below in conjunction with embodiment and accompanying drawing.

The prestressed FRP sheet anti-shear strengthening concrete beam experimental device of the present invention includes a steering device 2 arranged at the junction of the flange plate and the web of the concrete beam, an anchoring device 3 at the front end of the FRP sheet, a steel bead 5 in the middle of the FRP sheet, and an FRP sheet Anchor device at back end of sheet 4, FRP sheet tension end fixture 10, front steel plate at tension end 12, rear steel plate at tension end 13, jack 14, limit device 6, stabilizing device 7, jack support 17, tension stand 19. Polytetrafluoroethylene plate 18. Screw rod 11 connected to the clamp at the tension end of the FRP sheet and passing through the steel plate at the front of the tension end and the steel plate at the rear of the tension end.

The steering device 2 includes an inner steering block 20 embedded in the protective layer of the concrete beam 1, an outer steering block 21, a bolt 22 for fixing the inner steering block 20 and the outer steering block 21, and the bolt 22 passes through the inner steering block 20 and the outer steering block 21. Tighten with nut behind the outer steering block 21.

The anchoring device 3 at the front end of the FRP sheet, the steel bead 5 in the middle of the FRP sheet and the anchoring device 4 at the rear end of the FRP sheet have the same structure, and all include an inner backing plate 23 embedded in the protective layer of the concrete beam 1, an outer pressing plate 24 and Expansion bolts 25, said expansion bolts 25 are tightened with nuts after passing through the inner backing plate 23 and the outer pressure plate 24.

Described position-limiting device 6 comprises front steel plate 26, diagonal support 27, bottom steel plate 28, rubber backing plate 29, and described front steel plate 26, diagonal support 27, bottom steel plate 28 are mutually welded together, and described rubber backing plate 29 is placed on In front of the front steel plate 26, it is used to adjust the position of the concrete beam 1, and the limit device 6 is anchored to the ground at the bottom steel plate 28 with anchor bolts 8.

The FRP sheet tension end clamp 10 includes an upper T-shaped clip 30 and a lower T-shaped clip 31, and the upper T-shaped clip 30 and the lower T-shaped clip 31 are connected by bolts and clamp the FRP sheet 9.

The screw 11 passes through the round holes 32 of the upper T-shaped clip 30 and the lower T-shaped clip 31 , and is tightened and limited by an outer limit nut 33 .

The stabilizing device 7 includes an upper ear-type anchoring device 34, a lower ear-type anchoring device 35, an oblique rod 36, a connecting sleeve 37 and an anchor bolt 38, and the oblique rod 36 is connected with the upper ear-type anchoring device 34 and the lower The ear-type anchoring device 35 is connected through a bolt 39 , and the oblique rod 36 can rotate around the bolt 39 to adjust its position, and is connected through a connecting sleeve 37 . The stabilizer 7 is anchored to the ground at the lower lug anchor 35 using anchor bolts 38 .

The upper lug-type anchoring device 34 and the lower lug-type anchoring device 35 have the same structure, and both include an anchoring base plate 40 and a lug 41 with a round hole, and the lug 41 with a round hole is welded to the anchoring base plate 40 connections.

The upper lug-type anchoring device 34 is anchored to the side of the concrete beam 1 using anchor bolts 38 , and the lower lug-type anchoring device 35 is connected to the bottom steel plate 28 using anchor bolts 38 .

The screw rod 11 passes through the front steel plate 12 and the rear steel plate 13, is limited by the middle limit nut 15, and is fixed with the rear steel plate 13 by the outer anchor nut 16.

After the jack 14 pushes the steel plate 13 to move to the right on the polytetrafluoroethylene plate 18, it drives the screw rod 11, the FRP sheet tension end clamp 10 and the FRP sheet 9 to move to the right together, and the FRP sheet 9 is pre-stressed. stress.

The material of the FRP sheet 9 is carbon fiber sheet (CFRP), aramid fiber sheet (AFRP), basalt fiber sheet (AFRP) or glass fiber sheet (BFRP), or two or more of the above materials compound.

Now take the experiment of prestressed FRP sheet anti-shear strengthening concrete beam as an example to illustrate:

(1) Precast the concrete beam 1 according to the design requirements and install it in place.

(2) Prefabricate the concrete beam limiting device 6 and the concrete beam stabilizing device 7 according to the design requirements, use anchor bolts 8 and anchor bolts 38 to install them in place at the predetermined positions, and place a rubber backing plate 29 before the front steel plate 26 of the limiting device 6, Adjustment, restraint and stabilization of concrete beams1.

(3) According to the design requirements, prefabricate the steering device 2 at the junction of the flange plate and the web of the concrete beam, the anchoring device 3 at the front end of the FRP sheet, the steel bead in the middle of the FRP sheet 5, and the anchoring device 4 at the rear end of the FRP sheet. 20 and the inner backing plate 23 are embedded in the preset position of the concrete beam protective layer.

(4) Use epoxy resin adhesive to infiltrate the FRP sheet 9, pass through the steering device 2, the anchoring device 3 at the front end of the FRP sheet, the steel bead 5 in the middle of the FRP sheet and the anchoring device 4 at the rear end of the FRP sheet, and place the Outer turning block 21, outer pressure plate 24 are installed in place.

(5) Prefabricate FRP sheet tension end fixture 10, tension end front steel plate 12, tension end rear steel plate 13 according to the design requirements, and FRP sheet tension end fixture 10, tension end front steel plate 12, tension end The rear steel plates 13 are connected together with screw rods 11, and the outer anchor nuts 16 are tightened.

(6) Place the jack support 17, the polytetrafluoroethylene plate 18 and the jack 14.

(7) Put the FRP sheet between the upper T-shaped clip 30 and the lower T-shaped clip 31, tighten the bolts, and clamp the FRP sheet.

(8) Use the jack 14 to push the steel plate 13 to move to the right on the polytetrafluoroethylene plate 18, and drive the screw rod 11, the FRP sheet tension end clamp 10 and the FRP sheet 9 to move to the right together, and the FRP sheet 9 Apply prestress.

(9) Tighten the bolts on the steering device 2, the anchoring device 3 at the front end of the FRP sheet, the steel bead 5 in the middle of the FRP sheet, and the anchoring device 4 at the rear end of the FRP sheet to fix the FRP sheet.

(10) Keep the tension constant, tighten the middle limit nut 15, and remove the jack 14.

(11) After the epoxy resin is completely cured, cut the FRP sheet at the right end of the anchoring device 4 at the rear end of the FRP sheet to realize the shear reinforcement of the prestressed FRP.

The foregoing embodiments are only preferred implementations of the present invention. It should be pointed out that those skilled in the art can make several improvements and equivalent replacements without departing from the principle of the present invention. Technical solutions requiring improvement and equivalent replacement all fall within the protection scope of the present invention.

Claims (7)

1. a kind of pre-stress FRP sheet material Shear Strengthening beams of concrete experimental provision, which is characterized in that the device includes beams of concrete （1）, beams of concrete described in face（1）The stretching bed seat of web side（19）, be arranged in beams of concrete（1）Flange plate and web are handed over Connect the transfer at place（2）, be arranged in beams of concrete（1）The FRP sheet material front ends portion anchor of web bottom end（3）, setting exist Beams of concrete（1）FRP sheet material middle part steel press strips in the middle part of web（5）, be arranged in beams of concrete（1）On the downside of flange plate outer end FRP sheet materials rear end anchor（4）, setting be mounted on beams of concrete（1）The limiting device of web side（6）And stabilising arrangement （7）, be secured transverse to the stretching bed seat（19）On jack（14）, be located at the jack（14）Before the stretching end of both sides Steel plate（12）With steel plate after stretching end（13）, pass through the stretching end front spring（12）With steel plate after stretching end（13）Screw rod （11）, be arranged in screw rod（11）Neighbouring beams of concrete（1）The FRP sheet material stretching end fixtures of one end（10）, the stabilising arrangement （7）Including upper slotting ear formula anchor（34）, lower slotting ear formula anchor（35）, the connection upper slotting ear formula anchor（34） With lower slotting ear formula anchor（35）Brace（36）, be sleeved on the brace（36）On branch sleeve（37）With setting described Lower slotting ear formula anchor（35）On anchor bolt（38）, the brace（36）Both ends pass through bolt（39）Respectively with upper slotting ear Formula anchor（34）With lower slotting ear formula anchor（35）Installation connection.

2. pre-stress FRP sheet material Shear Strengthening beams of concrete experimental provision according to claim 1, which is characterized in that institute State transfer（2）Including being embedded into beams of concrete（1）Interior steering block in protective layer（20）, pass through bolt respectively（22）It is fixed In the interior steering block（20）The outer steering block at both ends（21）, the bolt（22）Across interior steering block（20）With outer steering block （21）It is tightened afterwards with nut.

3. pre-stress FRP sheet material Shear Strengthening beams of concrete experimental provision according to claim 1, which is characterized in that institute State FRP sheet material front ends portion anchor（3）, FRP sheet material middle part steel press strips（5）With FRP sheet materials rear end anchor（4）Structure phase Together, include being embedded into beams of concrete（1）Interior backing plate in protective layer（23）, outer plate（24）And expansion bolt（25）, described Expansion bolt（25）Across interior backing plate（23）And outer plate（24）It is tightened afterwards with nut.

4. pre-stress FRP sheet material Shear Strengthening beams of concrete experimental provision according to claim 1, which is characterized in that institute State limiting device（6）Including front spring（26）, bearing diagonal（27）, bottom steel plate（28）The tripod of composition is arranged in the preceding steel Plate（26）The rubber mat plate in outside（29）, for adjusting beams of concrete（1）Position, the limiting device（6）In bottom steel plate （28）Place uses foundation bolt（8）It is anchored at ground.

5. pre-stress FRP sheet material Shear Strengthening beams of concrete experimental provision according to claim 1,2,3 or 4, feature It is, the FRP sheet materials stretching end fixture（10）Including upper T-type intermediate plate（30）With pass through bolt and upper T-type intermediate plate（30）Connection Lower T-type intermediate plate（31）, the upper T-type intermediate plate（30）With lower T-type intermediate plate（31）Clamp FRP sheet materials（9）.

6. pre-stress FRP sheet material Shear Strengthening beams of concrete experimental provision according to claim 5, which is characterized in that institute State screw rod（11）Across upper T-type intermediate plate（30）With lower T-type intermediate plate（31）On circular hole（32）, use outer limit screw cap（33）It twists Tightly, it limits.

7. pre-stress FRP sheet material Shear Strengthening beams of concrete experimental provision according to claim 1,2,3 or 4, feature It is, the upper slotting ear formula anchor（34）With lower slotting ear formula anchor（35）Structure is identical, includes anchoring bottom steel plate （40）With setting in anchoring bottom steel plate（40）On the slotting ear with circular hole（41）.