CN204354493U - Fiber-reinforced composite muscle smart grid - Google Patents

Abstract

The utility model discloses a fiber-reinforced composite tendon intelligent grid. During the laying process of the warp and latitude tow of the grid, an optical fiber grating sensor is embedded in the fiber tow in the same direction; the fiber grating sensor is made of fiber The casing is packaged, and after laying, it is impregnated with resin and cured together with the warp and weft fiber bundles, and the initial contact position between the fiber grating sensor and the warp and weft fiber bundles is protected by a metal hose to form a smart grid with self-monitoring function . The utility model has the advantages of stable signal transmission, high monitoring precision, stable grid performance, convenient manufacture, and is suitable for industrialized mass production.

Description

Fiber-Reinforced Composite Rib Smart Grid

technical field

The invention relates to an intelligent structural material, in particular to an intelligent grid of fiber-reinforced composite bars.

Background technique

The fiber-reinforced composite rib grid in the prior art is an integral composite material formed by impregnating high-performance continuous fibers such as carbon fiber, glass fiber, and basalt fiber in epoxy resin, unsaturated polyester resin, and vinyl resin to form a grid. This kind of fiber-reinforced composite bar grid has the advantages of light weight, high strength, two-way force, convenient construction, suitable for ordinary environments and harsh environments, and can overcome the shortcomings of traditional building materials, and has more application advantages, specifically shown in :

The fiber-reinforced composite bar grid has reinforcement effects in two directions at the same time, which can be easily applied to the reinforcement of concrete slabs, effectively improving the bearing capacity of its concrete slabs, and the ductility of the reinforced specimens is good, and there are obvious signs before failure; The fiber-reinforced composite bar grid is pasted on the side of the masonry wall by mortar or resin, which can significantly improve the shear bearing capacity of the wall and enhance the integrity of the wall. The low-cycle repeated load test shows that its effect on ductility and energy dissipation The fiber-reinforced composite bar grid can be bent into a suitable shape and is easy to maintain. It has good applicability for strengthening and repairing the aging of the concrete structure on the top of the tunnel, concrete falling off and other diseases; of course, the fiber-reinforced composite bar grid is also It can be used for shear and bending reinforcement of ordinary beams, and its effect and cost are better than that of fiber cloth reinforcement. Distributed optical fiber sensing technology has been continuously applied to structures in recent years because of its test distribution, network, and stability. health monitoring. At present, the differences in the test principles of distributed optical fiber sensing technology in the world are mainly divided into intensity type, interference type and scattering type. Among them, BOTDR, BOTDA and other sensing technologies based on the Brillouin scattering mechanism are favored by scholars at home and abroad due to their great advantages in temperature and strain measurement accuracy and long measurement distance.

Integrating distributed sensing optical fibers into the fiber composite rib grid can form a smart structural material. In this way, not only the fragile optical fiber is well protected in actual use, but at the same time, when the fiber-reinforced composite bar smart grid is used to strengthen the structure in the civil field, the structure can be monitored in real time while the structure is reinforced, which is better. The safety performance of the evaluation structure. It has become a technical problem to be solved urgently to develop a fiber-reinforced smart grid manufacturing method that guarantees precision and is suitable for industrial mass production.

Contents of the invention

Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a smart grid of fiber-reinforced composite bars. In order to give full play to the advantages of fiber composite reinforcement grid in structural reinforcement, and at the same time realize real-time monitoring of the structure reinforced with the smart grid, so as to reliably evaluate the safety performance of the structure.

Technical solution: In order to solve the above technical problems, the fiber-reinforced composite bar smart grid provided by the present invention includes fiber tows, resins and optical fiber sensors, the fiber tows form a criss-cross fiber grid, and the resin is coated on On the fiber grid, the optical fiber sensor and the fiber sleeve wrapped outside it form a high-precision optical fiber sensor, and the end of the fiber sleeve has an anchoring section bonded to the optical fiber sensor.

Preferably, in order to protect the good transmission of the signal of the sensor lead wire, the contact position between the high-precision optical fiber sensor and the end of the fiber bundle is covered with a metal hose.

Preferably, the length of the metal hose embedded in the fiber tow is not less than 2 cm, and the length of the exposed fiber tow is not less than 2 cm.

Preferably, in order for the sensor to monitor the deformation of the grid with high precision, the high-precision optical fiber sensor is located at the center of the cross-section of the fiber grid. And it is stretched and tightened during the placement process of the high-precision optical fiber sensor.

Preferably, in order to make the whole sensor soft and easy to bend, the fiber sleeve on the surface of the high-precision optical fiber sensor is not impregnated with resin.

Preferably, the high-precision optical fiber sensor is arranged in the fiber grid in an S-shape.

The optical fiber is preferably a slip-free optical fiber or a long gauge optical fiber.

During manufacture, the optical fiber encapsulated in the fiber sleeve is used as a high-precision optical fiber sensor, and then it is made into a fiber-reinforced smart grid with fiber tow and resin by vacuum molding, including the following steps:

1) Make a bottom mold and apply a release agent on the bottom mold;

2) According to the grid spacing of the designed fiber-reinforced composite reinforcement, select the size of the filling mold, and install the filling mold on the bottom mold through bolts to form a grid channel;

3) Around the bottom mold, determine the fiber tow fixing card on the extension line of the grid channel;

4) Deploying resin, impregnating the fiber tow with resin;

5) Lay the warp and weft fiber tows along the grid channel, and fix the ends on the fixing clips;

6) When the fiber tow is laid to half of the design volume, place a high-precision optical fiber sensor;

7) Lay the remaining half of the fiber tow;

8) Use resin to completely infiltrate the formed grid-shaped fiber bundles and cover the release cloth;

9) Place the bead at the position of the fiber tow above the release cloth;

10) Lay diversion nets and diversion pipes within the range of the above-mentioned fiber mesh;

11) Set the sealing glue on the periphery of the fixed card of the bottom mold not less than 5cm;

12) Cover the entire mold with the vacuum bag, and the surrounding of the vacuum bag is tightly bonded with the sealing glue, and start vacuuming;

13) After the vacuum degree reaches the specified value, lay an electric heating blanket on the surface of the vacuum bag and set the heating temperature;

14) Continue heating and vacuuming for 1~2 hours, the resin is cured, and the grid is completed.

Beneficial effects: the present invention encapsulates the optical fiber with a fiber sleeve to make an optical fiber sensor, which overcomes the problem that the optical fiber is easily broken in the actual operation process, and greatly improves the survival rate in engineering application and production process. The product produced by the invention has distributed sensing and stable long-term monitoring performance, and has high cost performance. At the same time, using the vacuum forming process, there is no redundant resin in the system, less air bubbles, high fiber content, higher strength, and more stable performance; under the action of vacuum, the pressure of different parts of the same product is equal, and the fiber bundle and optical fiber sensor The interface is tightly bonded, the resin content is relatively balanced, and the performance is relatively stable; the flow and curing process of the resin is carried out in a relatively closed space, and there will not be a large amount of irritating odor emitted, which is more environmentally friendly; the production process is simple to operate and easy to master. Suitable for industrial mass production.

In addition to the above-mentioned technical problems solved by the present invention, the technical features constituting the technical solutions, and the advantages brought by the technical features of these technical solutions, other technical problems that the fiber-reinforced composite bar smart grid of the present invention can solve , other technical features contained in the technical solution and the advantages brought by these technical features will be further described in detail in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is a schematic structural view of an optical fiber sensor in an embodiment of the present invention;

Fig. 2 is the structural representation of base mold and filling mold in the embodiment of the present invention;

Fig. 3 is a laying diagram of fiber tow in the channel in the embodiment of the present invention;

Fig. 4 is a schematic diagram of the layout of the optical fiber sensor in the embodiment of the present invention;

Fig. 5 is a schematic diagram of the completion of fiber tow laying in the embodiment of the present invention;

Fig. 6 is a schematic diagram of the installation of auxiliary materials for the vacuum molding process of the present invention;

Fig. 7 is the sectional view of Fig. 5;

Fig. 8 is a schematic diagram of forming a smart grid;

In the figure: 1 bottom mold, 2 positioning card, 3 filling mold, 4 bolt, 5 fiber tow, 5-1 fiber tow roll, 6 optical fiber sensor, 6-1 optical fiber, 6-2 fiber sleeve, 6-3 Anchor section, 6-4 metal hose for bending section, 6-5 metal hose for the contact part between optical fiber sensor and fiber tow, 7-1 horizontal bead, 7-2 longitudinal bead, 8 diversion net, 9 diversion tube, 10 Sealing clay, 11 vacuum film, 12 electric heating blanket, 13 resin collector, 14 vacuum pump, 15 release cloth.

Detailed ways

Example:

In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation manners of the present invention will now be described with reference to the accompanying drawings.

Fig. 1 is a schematic diagram of the packaging structure of an optical fiber sensor. The fiber 6-1 is surrounded by a fiber sleeve 6-2, and the anchoring section uses a resin 6-3 to firmly bond the optical fiber and the fiber sleeve to form a high-precision optical fiber sensor.

Fig. 2 is a schematic diagram of the connection structure between the bottom mold 1 and the filling mold 3. The filling mold 3 is fixed on the bottom mold 1 by bolts 4 to form a grid channel for laying fiber tows. Positioning card 2 is arranged on the channel center line.

Fig. 3 is a schematic diagram of laying fiber tow 5 in the channel. The fiber tows 5 are laid at intervals in the warp and weft directions in the grooves formed by the array arrangement of the filling molds 3 , and are kept continuously and tautly laid all the time.

Fig. 4 is a schematic diagram of the layout of the fiber optic sensor. When the fiber tow 5 is wound to half of the designed amount, stop winding. The sensor 6 is arranged in the grid channel to ensure that the sensor is placed centrally in the channel. When the sensor is arranged in an S-shaped bend and at the beginning and end positions where the sensor is in contact with the fiber tow, a metal hose 6-4 in the bending section and a metal hose 6-5 at the contact position between the optical fiber sensor and the fiber tow must be installed. While the sensor is held straight and taut, wind the remaining fiber silk. After the winding is completed, correct the embedded length of the metal hose in the fiber tow. The embedded length should not be less than 2cm, and the exposed length should not be less than 2cm, so as to ensure that the signal line of the optical fiber sensor is not broken and can be well protected.

Figure 5 shows the laying of the release cloth 15. After the laying is completed, the bead is laid in the channel, and the bead includes a horizontal bead 7-1 and a longitudinal bead 7-2. In order to facilitate the free adjustment of the compression amount of the warp and weft fiber tow 5 under the vacuum state, the uniformity and compactness of the fiber silk are guaranteed.

Fig. 6 is a schematic diagram of installation of auxiliary materials for the vacuum molding process. Lay the diversion net 8 first, and then lay the diversion pipe 9 to discharge excess resin and air bubbles from the vacuum film. , the vacuum film 11 is bonded to the sealing cement 10 to complete the installation of the entire process auxiliary material. After the connection of the whole equipment is completed, the vacuum pump 14 is turned on, and the excess resin is introduced into the resin collector 13. When the reading of the vacuum pressure gauge is close to 0, an electric heating blanket 12 is laid for rapid curing.

Figure 7 is a cross-sectional view of Figure 6, which can clearly reflect the material laying position of each step in the grid production process. The production steps are as follows:

The first step: firstly make a flat and clean base mold 1 that is impermeable to epoxy resin. The bottom mold 1 is designed with bolt holes corresponding to the bolt holes 4 of the filling mold 3, and a layer of release agent is applied on the surface of the bottom mold;

The second step: design the filling mold 3 according to the size of the fiber-reinforced composite bar grid. The length and width dimensions of the filling mold 3 tend to be consistent with the size of the composite rib grid, the thickness is 1-2 cm, the material is steel plate, and the shape can be square or rectangular according to the grid size made. Two symmetrical anchor holes are drilled on both sides of the center line of the filling mold 3, and the positions correspond to the bolt holes on the bottom mold 1.

The third step: fix the filling mold 3. The bottom mold 1 and the filling mold 3 are connected as a whole by bolts 4, and the filling mold 3 is arranged in an array in front, back, left, and right, and a channel of 0.8~1cm is reserved between two adjacent filling molds to form a grid channel. Used for laying warp and weft fiber tows 5.

Step 4: Set the positioning card 2. On the center line of the channel, and 5~10cm away from the outermost ring filling mold, set the positioning card 2.

Step 5: laying fiber tow 5 . The fiber tow 5 is impregnated with resin first, and the pressing is repeated several times during the impregnation process to ensure that the resin is completely soaked. The warp and weft fiber tows 5 are laid continuously in the channel, and one layer is laid radially and one layer is intersected in the weft direction. When laying, the fiber tow 5 should be stretched and tightened. After laying along a channel and reaching the end point, the fiber tow 5 bypasses the positioning card 2 and is transferred to the adjacent channel for laying. In this way, the fiber tow 5 is laid layer by layer. Complete half of the design layers.

Step 6: Place the optical fiber sensor 6 so that it is centered in the channel, keep the sensor in a straight state, and continue to wind the remaining fiber tows to the designed number of layers.

Step 7: laying release cloth 15 . After the laying of warp and weft fiber tows 5 is completed, one deck of release cloth 15 is covered on its upper surface, and the size of the release cloth 15 is advisable to cover the fiber tows 5 in the channel.

Step 7: Place the bead 7 on the upper surface of the release cloth 15, and place the bead in the channel where the warp and weft fiber tows 5 are laid. Step 8: laying the diversion net 8. Lay one deck diversion net 8 after bead laying is finished, diversion net size is as the criterion to cover the fiber in the channel.

Step 9: laying the diversion pipe9. The upper surface of the diversion net 8 is laid with diversion pipes 9 , and the radiation width of one diversion pipe 9 is 15 to 20 cm. The laying length and spacing of the diversion pipes are selected according to the area of the diversion net 8 .

Step 10: laying the sealant 10. A circle of sealing glue 10 is pasted on the perimeter of the bottom mold 1 and the perimeter of the straight line 5cm where the positioning card 2 is located.

The eleventh step: laying the vacuum film 11 . The length of each side of the vacuum film 11 is not less than 10cm longer than that of the bottom mold 1, and the four sides are pasted on the sealing glue 10 and pressed tightly.

The twelfth step: vacuum molding. Connect the vacuum pump 14, the resin collector 13 and the guide tube 9, one end of the resin collector 13 is connected to the guide tube 9, and the other end is connected to the vacuum air compressor 14.

The thirteenth step: laying the electric heating blanket 12 . When the reading of the vacuum pressure gauge is close to 0, a layer of electric heating blanket 12 is laid on the surface of the vacuum membrane 11, and the upper limit of the heating temperature is set. Vacuum while heating until the resin is completely cured, stop vacuuming, and the grid is completed. The completed smart grid is shown in Figure 8.

The embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, within the scope of the principles and technical ideas of the present invention, various changes, modifications, substitutions and deformations to these embodiments still fall within the protection scope of the present invention.

Claims (7)

1. A fiber-reinforced composite rib smart grid, comprising fiber tows, resins and optical fiber sensors, the fiber tows form a criss-cross fiber grid, and the resin is coated on the fiber grid, characterized in that: The optical fiber sensor and the fiber sleeve wrapped outside it form a high-precision optical fiber sensor, and the end of the fiber sleeve has an anchoring section bonded to the optical fiber sensor. 2. The fiber-reinforced composite tendon smart grid according to claim 1, characterized in that: the contact part between the high-precision optical fiber sensor and the end of the fiber tow is covered with a metal hose. 3. The fiber-reinforced composite tendon smart grid according to claim 2, characterized in that: the length of the metal hose embedded in the fiber tow is not less than 2 cm, and the length of the exposed fiber tow is not less than 2 cm. 4. The fiber-reinforced composite bar smart grid according to claim 1, characterized in that: the high-precision optical fiber sensor is located at the center of the cross-section of the fiber grid. 5. The fiber-reinforced composite bar smart grid according to claim 1, characterized in that: the fiber sleeve on the surface of the high-precision optical fiber sensor is not impregnated with resin. 6. The fiber-reinforced composite bar smart grid according to claim 2, characterized in that: the high-precision optical fiber sensor is arranged in the fiber grid in an S-shape. 7. The fiber-reinforced composite tendon smart grid according to claim 1, wherein the optical fiber sensor is a non-slip optical fiber or a long gauge optical fiber.