A pressure balancing plate, mold and preparation method for preparing glass fiber reinforced plastic road panel

Abstract

The present invention provides a pressure-equalizing plate, mold, and preparation method for preparing fiberglass road panels. The pressure-equalizing plate includes a plate body, one side of which is provided with a concave pattern. The plate body is also provided with multiple drainage grooves running through both sides of the plate body. The pressure-equalizing plate is used to lay between a fiber fabric and a vacuum auxiliary material during the vacuum infusion process to form the fiberglass road panel, with the concave pattern facing the fiber fabric to apply pressure to the fiber fabric. Using this pressure-equalizing plate, mold, and preparation method, the fiberglass road panel produced has a mold surface with good flatness on its upper surface, eliminating the need for overall polishing and repairing, and can be sprayed to form a sandblasted anti-slip layer. The lower surface has a non-slip textured surface with a clear, regularly arranged pattern.

Description

Technical Field

[0001] The present invention belongs to the technical field of glass fiber reinforced plastic composite material forming, and particularly relates to a pressure equalizing plate, a mold and a preparation method for preparing glass fiber reinforced plastic road panels. Background Art

[0002] Fiberglass road panel is a kind of emergency repair material for military airport pavement. It has significant advantages such as good mobility, easy operation, fast repair speed and good carrying capacity. It has been used at home and abroad for many years.

[0003] The fiberglass road panel (also known as the panel or nine-piece panel) is 9m long, 1.8m wide, and 8mm thick. The nine panels are joined together using high-strength fiber ties. The ties are placed in the middle of the panel thickness and embedded in the panels to the same length, leaving a 20mm exposed width. The panel has a sandblasted anti-slip coating on the top and a non-slip texture on the bottom.

[0004] In the early days, domestic fiberglass road panels were mostly formed using the hand lay-up process. The hand lay-up molds were made of steel plates with dense circular pits on the surface formed by pickling. During manufacturing, the molds were first sprayed with gel coat, and then the alkali-free glass fiber cloth was applied layer by layer using the hand lay-up process to form the board. After demolding, the mold surface of the board was formed into a dense circular protrusion.

[0005] At present, the mainstream road slab forming process in China is mainly vacuum infusion process. Compared with the hand lay-up process, the vacuum infusion process has significant advantages: less volatile substances are produced during the forming process, and it is environmentally friendly; the process operation is simple and easy for employees to use; it is less affected by human factors and is operated according to a fixed laying method, which makes the product performance reproducible and the quality stable; the resin flows along the fiber pores under the action of high vacuum, so that the product has fewer pores and better apparent quality; under the same laying conditions, the vacuum infusion process products have a high fiber content, a thin and uniform thickness, and higher strength.

[0006] The vacuum infusion process is a typical single-sided molding process, resulting in products with a "smooth one side and a rough one side." One side of the product is the mold surface, while the other side is the auxiliary material surface. The mold surface can better reproduce the mold details, while the auxiliary material surface is generally formed into a rough surface by a release cloth, which facilitates post-processing.

[0007] A Chinese patent document with publication number CN113561518A discloses a mold for preparing FRP road panels, which is suitable for the mold of integrated vacuum infusion molding of FRP road panels. In this patent, a FRP patterned plate is covered on the surface of the mold steel plate as the mold surface, and the surface of the patterned plate has circular pits. When the plate body is formed, glass fiber fabric is laid on the mold surface, a connecting belt is laid on the inner baffle, and the upper and lower parts of the inner baffle are fixed with bolts. Then, auxiliary materials are laid according to the requirements of the vacuum infusion process, and a vacuum film is coated. After vacuuming, resin is infused, and the resin is cured and molded. After the plate body is demoulded, the mold surface has a circular protrusion, and the other side has a rough surface after removing the auxiliary material. Due to the limitations of the vacuum infusion process, the rough surface is prone to cloth grain, local pits, protrusions, etc., and the flatness is poor. Before making the sandblasting anti-slip layer, the entire surface needs to be polished and repaired to make it smooth before continuing. The entire panel is extremely labor-intensive to sand, even exceeding the required work required to form the panel. The sanding process also generates a large amount of dust, breaking the fibers on the panel's surface and reducing its strength. Furthermore, the bolts create circular holes at the hinged joints of the connecting straps, reducing their overall strength and aesthetics. Summary of the Invention

[0008] The present invention aims to solve the technical problem that the current vacuum-infused glass fiber reinforced plastic road panel has a mold surface on one side and an auxiliary material surface on the other side, the auxiliary material surface is a rough surface with poor flatness, and needs to be polished and repaired before sandblasting the anti-skid layer, which is extremely labor-intensive. The present invention provides a pressure-equalizing plate, a mold and a preparation method for preparing the glass fiber reinforced plastic road panel. By using the pressure-equalizing plate, the mold and the preparation method, the upper surface of the prepared glass fiber reinforced plastic road panel is the mold surface, which has good flatness and can be sprayed without overall polishing and repairing to form a sandblasted anti-skid layer. The lower surface is an anti-skid textured surface with clear patterns and regular arrangement.

[0009] In order to solve the above problems, the first aspect of the present invention provides a pressure equalizing plate for preparing a glass fiber reinforced plastic road panel:

[0010] It includes a pressure equalizing plate main body, one side of which is provided with a concave pattern, and the pressure equalizing plate main body is also provided with a plurality of drainage grooves running through the two sides of the pressure equalizing plate main body; the pressure equalizing plate is used to be laid between the fiber fabric and the vacuum auxiliary material when the glass fiber reinforced plastic road panel is formed by the vacuum infusion process, and the concave pattern is facing the fiber fabric to apply pressure to the fiber fabric.

[0011] Preferably, the drainage grooves include a plurality of longitudinal drainage grooves and a plurality of corner drainage grooves;

[0012] The longitudinal drainage groove is arranged along the width direction of the pressure equalizing plate body, and a plurality of the longitudinal drainage grooves are arranged at intervals along the longitudinal direction of the pressure equalizing plate body;

[0013] The angle between the length direction of the edge and corner drainage grooves and the width direction of the equalizing plate body is 30-60°; the edge and corner drainage grooves are respectively arranged at the four corners of the equalizing plate body.

[0014] Preferably, starting from the width side of the pressure equalizing plate body, a longitudinal drainage groove is arranged at equal intervals; the length of the longitudinal drainage groove becomes shorter from the longitudinal drainage groove located in the middle of the pressure equalizing plate body to the longitudinal drainage grooves on both sides.

[0015] Preferably, a total of 15-19 longitudinal drainage grooves are provided; the length of the longitudinal drainage groove located in the middle of the pressure equalizing plate body is 0.6-0.7 times the width of the pressure equalizing plate body; the length of the longitudinal drainage groove located at the outermost side of the pressure equalizing plate body is 0.5-0.6 times the width of the pressure equalizing plate body; the length of the longitudinal drainage groove is shortened by equal values ​​from the longitudinal drainage groove located in the middle of the pressure equalizing plate body to the longitudinal drainage grooves on both sides;

[0016] A corner drainage groove is provided at each corner of the pressure equalizing plate body, and the length of the corner drainage groove is 0.1-0.2 times the width of the pressure equalizing plate body;

[0017] The width of the longitudinal drainage groove and / or the corner drainage groove is 1-2 mm; the thickness of the pressure equalizing plate body is 3-5 mm.

[0018] A second aspect of the present invention provides a mold for preparing a glass fiber reinforced plastic road panel:

[0019] It includes a mold body and the above-mentioned pressure balancing plate for preparing glass fiber reinforced plastic road panels;

[0020] The mold body includes a mold plate, an outer rib, and an inner rib; the outer rib and the inner rib are arranged on the upper surface of the mold plate; the inner side surface of the outer rib and the upper surface of the mold plate form a molding area suitable for molding a glass fiber reinforced plastic road panel; the inner rib is arranged in the molding area, and the inner side surface of the outer rib, the upper surface of the mold plate and the side surface of the inner rib form a sub-molding area suitable for molding a single plate of the glass fiber reinforced plastic road panel; the inner rib includes an upper rib and a lower rib, the lower rib is connected to the upper surface of the mold plate, the upper rib is located above the lower rib, and the upper rib and the lower rib are suitable for clamping and fixing the connecting belt of the glass fiber reinforced plastic road panel;

[0021] The pressure equalizing plate is suitable for being placed above the fiber fabric in the sub-forming area.

[0022] Preferably, the pressure balancing plate is a glass fiber reinforced plastic plate, and the material of the glass fiber reinforced plastic plate is a glass fiber reinforced epoxy resin composite material; the upper baffle is a glass fiber reinforced plastic pultruded profile.

[0023] A third aspect of the present invention provides a method for preparing a glass fiber reinforced plastic road slab, which is prepared using the above-mentioned mold for preparing a glass fiber reinforced plastic road slab, and the preparation method comprises:

[0024] S1. Laying a first fiber fabric layer in the sub-molding area;

[0025] S2. Lay the connecting tape on the lower baffle along the length direction of the lower baffle, so that the two sides of the connecting tape are laid on the first fiber fabric layer in the sub-molding area on both sides, and fix the connecting tape to the lower baffle;

[0026] S3. Place the upper bar above the connecting strip and secure the upper bar to the connecting strip;

[0027] S4. Overlaying a second fiber fabric layer on top of the first fiber fabric layer in the sub-molding area, so that the second fiber fabric layer is docked with the connecting belt;

[0028] S5. Overlaying a third fiber fabric layer on top of the second fiber fabric layer in the sub-molding area to cover the connecting tape;

[0029] S6. Laying the equalizing plate above the third fiber fabric layer, with the side of the equalizing plate having the concave pattern facing downward;

[0030] S7. Laying vacuum auxiliary material above the equalizing plate, sealing the top of the mold, and then evacuating the mold and infusing the resin;

[0031] S8. Curing and molding the resin to obtain the fiberglass reinforced plastic road panel.

[0032] Preferably, the method further comprises applying an organic silicone film to the contact areas of the connecting belt with the upper stop bar and the lower stop bar before laying the connecting belt in step S2.

[0033] Preferably, the connecting belt is fixed to the lower baffle and the upper baffle by double-sided tape.

[0034] A fourth aspect of the present invention provides a glass fiber reinforced plastic road panel produced by the above-mentioned production method.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The equalizing plate for preparing FRP road panels of the present invention is used for vacuum infusion molding FRP road panels. When in use, the equalizing plate for preparing FRP road panels is laid between the uppermost fiber fabric and the vacuum auxiliary material. The equalizing plate can be used as the other side of the mold to apply pressure to the uppermost fiber fabric. The concave pattern on the equalizing plate forms a convex anti-slip pattern on the product surface. A through drainage groove is provided on the equalizing plate, and the vacuum-infused resin can penetrate downward into the fiber fabric through the drainage groove. The product obtained in this way has an upper surface as the mold surface with good flatness and a lower surface as the anti-slip textured surface, and no further polishing or repair is required.

[0037] Compared with the conventional vacuum infusion fiberglass road panel mold, the mold for preparing the fiberglass road panel of the present invention is equipped with an equalizing plate. When in use, the equalizing plate is laid between the fiber fabric and the vacuum auxiliary material, and the equalizing plate is used as the "other side mold". The drainage groove provided on the equalizing plate can drain the resin into the fiber fabric, thereby completing the penetration of the resin into the fiber fabric. The use of this mold can overcome the defect of "single-sided light" of the vacuum infusion process, so that the product has the characteristic of "two-sided light".

[0038] The preparation method of the fiberglass reinforced plastic road panel of the present invention adopts the above-mentioned mold for preparation. The upper surface of the obtained road panel is the mold surface, which has good flatness and does not require overall grinding and repair. It can be sprayed to form a sandblasted anti-slip layer. The lower surface is an anti-slip textured surface formed by a patterned equalizing plate, with clear patterns, regular arrangement, and beautiful appearance. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 Schematic diagram of the structure of the pressure equalizing plate for preparing the glass fiber reinforced plastic road panel according to Example 1 of the present invention;

[0040] Figure 2 Schematic diagram of the structure of the mold for preparing the glass fiber reinforced plastic road panel according to Example 8 of the present invention;

[0041] Figure 3 This is a schematic structural diagram of inner and outer ribs in a mold for preparing a fiberglass reinforced plastic road panel according to Example 8 of the present invention;

[0042] Figure 4 This is a schematic diagram of laying the connecting strip in the method for preparing a fiberglass reinforced plastic road panel according to Example 9 of the present invention;

[0043] Figure 5 This is a schematic diagram of laying vacuum auxiliary materials in the method for preparing a fiberglass road panel according to Example 9 of the present invention.

[0044] Among them: 1-pressure balancing plate body; 2-drainage groove; 21-longitudinal drainage groove; 22-corner drainage groove; 3-mold body; 31-mold plate; 32-outer retaining edge; 33-inner retaining edge; 331-upper retaining bar; 332-lower retaining bar; 4-steel frame; 5-glass fiber fabric; 6-connecting belt; 7-glue injection hose; 8-exhaust belt; 9-guide net. DETAILED DESCRIPTION

[0045] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention. Example

[0046] like Figure 1 As shown, the equalizing plate for preparing the FRP road panel of this embodiment includes an equalizing plate body 1, one side of the equalizing plate body 1 is provided with a concave pattern, and the equalizing plate body 1 is also provided with a plurality of drainage grooves 2 running through the two sides of the equalizing plate body 1; the equalizing plate is used to be laid between the fiber fabric and the vacuum auxiliary material when the FRP road panel is formed by the vacuum infusion process, and the concave pattern faces the fiber fabric to apply pressure to the fiber fabric.

[0047] The pressure-equalizing plate used in preparing FRP road slabs in this embodiment is used to form FRP road slabs using a vacuum infusion process. In the FRP road slab preparation mold described in Patent Publication No. CN113561518A, during vacuum infusion molding, a fiberglass fabric is placed in the mold, and a vacuum auxiliary material is placed above the top layer of fiberglass fabric. After molding, the product has a smooth surface on the side that contacts the mold, while a rough surface on the side that contacts the vacuum auxiliary material has poor flatness. This rough surface requires extensive polishing before applying the sandblasting anti-slip layer. Therefore, the present invention creatively proposes that during vacuum infusion molding of FRP road slabs, the pressure-equalizing plate used for preparing FRP road slabs is placed between the top layer of fiber fabric and the vacuum auxiliary material. The pressure-equalizing plate serves as the other side of the mold, and pressure is applied to the top layer of fiber fabric. The concave pattern on the pressure-equalizing plate forms a convex anti-slip pattern on the product surface. The resulting product has a mold-like top surface with good flatness, and a textured anti-slip bottom surface, eliminating the need for further polishing or repair. However, in the vacuum infusion process, resin is infused into the fabric using the vacuum auxiliary material. Because the pressure plate blocks the resin from soaking into the fabric, drainage grooves are provided throughout the pressure plate to allow the vacuum-infused resin to penetrate downward into the fabric. During use, the pressure plate is placed over the topmost layer of fabric, between the fabric and the vacuum auxiliary material, and conventional vacuum infusion is performed.

[0048] Due to the obstruction of the equalizing plate, the resin's infiltration rate and infiltration effect on the fiber fabric during vacuum infusion will inevitably be significantly affected. In order to improve the resin infiltration rate and infiltration effect, in some embodiments, the drainage groove 2 includes a plurality of longitudinal drainage grooves 21 and a plurality of corner drainage grooves 22; the longitudinal direction of the longitudinal drainage grooves 21 is arranged along the width direction of the equalizing plate body 1, and the plurality of longitudinal drainage grooves 21 are arranged at intervals along the length direction of the equalizing plate body 1; the angle between the length direction of the corner drainage grooves 22 and the width direction of the equalizing plate body 1 is 30-60°; the corner drainage grooves 22 are respectively arranged at the four corners of the equalizing plate body 1. Since the equalizing plate body has a certain length, arranging a plurality of longitudinal drainage grooves at intervals in its length direction can accelerate the rate of resin penetration and ensure that the fiber fabric in the length direction can be evenly infiltrated. The four corners of the equalizing plate body are far away from the injection tube, so arranging corner drainage grooves at the four corners can accelerate the resin infiltration rate and effect at the four corners.

[0049] In some embodiments, longitudinal drainage grooves 21 are provided at equal intervals starting from the width edge of the pressure equalizing plate body 1; the length of the longitudinal drainage grooves 21 decreases from the longitudinal drainage groove 21 located in the middle of the pressure equalizing plate body 1 toward the longitudinal drainage grooves 21 on both sides. Since the air extraction ports during vacuum infusion are usually located at the four corners, when the longitudinal drainage grooves are configured to be longer in the middle and shorter on both sides, the resin in the middle is first soaked, followed by the resin on both sides, which facilitates the discharge of air from the air extraction ports at the corners. This ensures that all glass fiber cloths are fully impregnated, eliminating infusion defects such as dry yarn and air inclusion.

[0050] In some embodiments, 15-19 longitudinal drainage grooves 21 are provided. If the longitudinal drainage grooves are too close together, the strength of the pressure equalizing plate will be reduced, making it very susceptible to damage. If the longitudinal drainage grooves are too far apart, the resin will not easily penetrate the fiber fabric, resulting in dry yarn and air inclusion, which will affect product performance. The inventors have experimented with various drainage groove placement methods and found that the above spacing allows for better resin penetration of the fiber fabric during infusion, while also maintaining the strength of the pressure equalizing plate and making it less susceptible to damage.

[0051] In some embodiments, the length of the longitudinal drainage groove located in the middle of the equalizing plate body is 0.6-0.7 times the width of the equalizing plate body; the length of the longitudinal drainage groove located at the outermost side of the equalizing plate body is 0.5-0.6 times the width of the equalizing plate body; the length of the longitudinal drainage groove is shortened by the longitudinal drainage groove located in the middle of the equalizing plate body to the longitudinal drainage grooves on both sides. The length of the drainage groove affects the pouring time of each glass fiber reinforced plastic road panel and the strength of the equalizing plate. If the drainage groove is too long, the strength of the equalizing plate will be significantly reduced. If the drainage groove is too short, the resin pouring time will be increased a lot, and the pouring risk will increase. Preferably, the length of the longitudinal drainage groove located in the middle of the equalizing plate body is 0.66 times the width of the equalizing plate body; the length of the longitudinal drainage groove located at the outermost side of the equalizing plate body is 0.55 times the width of the equalizing plate body. The aforementioned shortening by an equal difference means, for example, that the length of the longitudinal drainage groove shortens by 20 mm from the longitudinal drainage groove in the middle of the pressure equalizing plate body to the longitudinal drainage grooves on both sides.

[0052] In some embodiments, a corner drainage groove 22 is provided at each corner of the pressure equalizing plate body, and the length of the corner drainage groove 22 is 0.1-0.2 times the width of the pressure equalizing plate body. The corner is the weak point of the pressure equalizing plate and is also the last impregnation position. The drainage groove here can shorten the time of complete impregnation. On the one hand, the corner drainage groove should avoid being too close to the last longitudinal drainage groove to accelerate the longitudinal drainage effect. On the other hand, it should avoid being too close to the corner to destroy the corner strength.

[0053] In some embodiments, the width of the longitudinal drainage grooves and / or the corner drainage grooves is 1-2 mm. Due to the large size of the pressure balancing plate, the width of the drainage grooves cannot be narrowed due to processing conditions and cost constraints. Excessively wide drainage grooves will reduce the capillary effect of drainage. Therefore, based on existing conditions, the drainage grooves are processed as thin and straight as possible.

[0054] In some embodiments, the thickness of the main body of the balancing plate is 3-5 mm. If the balancing plate is too thick, its rigidity will be insufficient. On the one hand, the concave pattern will be partially deformed by atmospheric pressure and the action of the underlying fiberglass cloth, resulting in a shallower pattern. On the other hand, its service life will be greatly reduced. If the patterned plate is too thick, it will increase its weight significantly, making it very inconvenient to use. Furthermore, the increased thickness will increase the cost. While maintaining sufficient material rigidity, the balancing plate should be as thin as possible.

[0055] Specifically, in this embodiment, the pressure balancing plate is made of glass fiber reinforced plastic with a temperature resistance of 110°C. It includes a pressure balancing plate body 1 with an outer dimension of 9000*1800*3mm. One side of the pressure balancing plate body 1 is provided with a concave pattern. Figure 1 Open a through drainage groove.

[0056] The drainage groove 2 includes a longitudinal drainage groove 21 arranged along the width direction of the equalizing plate body 1 and four corner drainage grooves 22 respectively arranged at the four corners of the equalizing plate body 1. Starting from the outermost edge of the equalizing plate body, one longitudinal drainage groove 21 is set every 500mm, and a total of 17 are set. The length of the middle longitudinal drainage groove is 1200mm, and the length of the outermost longitudinal drainage groove is 1000mm. From the middle to the sides, the length of the longitudinal drainage groove decreases by 25mm. The angle between the length direction of the corner drainage groove 22 and the width direction of the equalizing plate body 1 is 30-60°, which is the angle of the line connecting the four corners of the equalizing plate to the corners of the last longitudinal guide groove. The length of each corner drainage groove 22 is 200mm, and the distance between the innermost point of the corner drainage groove and the outermost longitudinal drainage groove is 200mm. The width of the longitudinal drainage groove and the corner drainage groove is 1.5mm.

[0057] The equalizing plate is made of glass fiber fabric and epoxy resin through a vacuum infusion process. The preparation method is as follows: a PU anti-slip mat or a steel anti-slip plate with a convex pattern is fixed on a steel flat plate as a mold for the equalizing plate; after applying a release agent on the mold surface, the glass fiber fabric is laid, vacuum infusion auxiliary materials are arranged, and a vacuum bag is wrapped; a mold-curable epoxy resin is used, and the TG value can reach above 110°C after post-curing; the resin is infused under vacuum conditions and cured at room temperature; the auxiliary materials on the surface of the product are removed, the equalizing plate is demoulded, and the burrs are cut off; a 1-2mm wide through groove is opened; and a release agent is applied to both sides of the patterned equalizing plate for maintenance. Example

[0058] In this embodiment, the drainage grooves provided on the pressure equalizing plate are different from those in Example 1, except that four corner drainage grooves are not provided, and the rest of the structure is the same. Example

[0059] In this embodiment, the drainage grooves provided on the pressure equalizing plate are different from those in Example 1. The difference is that the 17 drainage grooves have the same length, which is 1200 mm. The rest of the structures are the same. Example

[0060] In this embodiment, the drainage grooves provided on the pressure equalizing plate are different from those in Example 1. The difference is that 8 drainage grooves are provided, the spacing between adjacent drainage grooves is 1000 mm, the length of the two middle drainage grooves is 1200 mm, and the length of the drainage grooves on both sides decreases by 25 mm. The rest of the structure is the same. Example

[0061] In this embodiment, the drainage grooves provided on the pressure equalizing plate are different from those in Example 1. The difference is that 29 drainage grooves are provided, the spacing between adjacent drainage grooves is 300 mm, the length of the two middle drainage grooves is 1200 mm, and the length of the drainage grooves on both sides decreases by 25 mm. The rest of the structure is the same. Example

[0062] In this embodiment, the drainage grooves provided on the pressure equalizing plate are different from those in Example 1. The length of the two middle drainage grooves is 1500 mm, and the length of the drainage grooves on both sides decreases by 25 mm. The rest of the structure is the same. Example

[0063] In this embodiment, the drainage grooves provided on the pressure equalizing plate are different from those in Example 1. The length of the two middle drainage grooves is 900 mm, and the length of the drainage grooves on both sides decreases by 25 mm. The rest of the structures are the same. Example

[0064] like Figure 2 、 Figure 3 As shown, this embodiment is a mold for preparing glass fiber reinforced plastic road panels, including a mold body 3 and the equalizing plate for preparing glass fiber reinforced plastic road panels of embodiment 1;

[0065] The mold body 3 includes a mold plate 31, an outer rib 32, and an inner rib 33; the outer rib 32 and the inner rib 33 are arranged on the upper surface of the mold plate 31; the inner side surface of the outer rib 32 and the upper surface of the mold plate 31 form a molding area suitable for molding fiberglass road panels; the inner rib 33 is arranged in the molding area, and the inner side surface of the outer rib 32, the upper surface of the mold plate 31 and the side surface of the inner rib 33 form a single-board molding area suitable for molding fiberglass road panels; the inner rib 33 includes an upper rib 331 and a lower rib 332, the lower rib 332 is connected to the upper surface of the mold plate 31, the upper rib 331 is located above the lower rib 332, and the upper rib 331 and the lower rib 332 are suitable for clamping and fixing the connecting belt of the fiberglass road panels; the equalizing plate is suitable for being laid above the fiber fabric in the molding area.

[0066] Furthermore, the mold also includes a steel frame 4 with a rectangular shape. The steel frame is arranged below the mold plate 31 and is connected to the lower end surface of the mold plate through a height adjustment member.

[0067] Among them, the outer guard 32 and the mold plate 31 can be connected by welding, the lower guard bar of the inner guard can be connected to the mold plate by welding, the upper surface of the lower guard bar of the inner guard can be connected to the fiber fabric by gluing, and the lower surface of the upper guard bar can be bonded to the fiber fabric by double-sided tape.

[0068] Among them, the pressure equalizing plate is a glass fiber reinforced plastic plate, and the material of the glass fiber reinforced plastic plate is a glass fiber reinforced epoxy resin composite material.

[0069] In this embodiment, the FRP road panel is constructed of nine continuous panels, 1.8 mm wide and 8 mm thick. The mold body is divided into nine separate molding zones by inner sidewalls. The outer sidewalls are 30 mm by 15 mm stainless steel bars welded to the mold plate, enclosing a 16370 mm by 9005 mm molding zone. The molding zone is approximately 0.05% larger than the product size to compensate for curing shrinkage. The lower sidewall of the inner sidewall is a 20 mm by 3 mm stainless steel bar welded to the plate surface, dividing the plate surface into nine 1801 mm by 9005 mm rectangular molding zones. The upper sidewall is a 20 mm by 10 mm pultruded FRP profile, or FRP square rod. Made from fiberglass yarn and epoxy resin through a pultrusion process, it has a TG value exceeding 110°C and needs to be cut into 9020-9040 mm sections. The FRP pultruded profiles offer excellent straightness, a smooth surface, and high strength, allowing for repeated use dozens of times.

[0070] To ensure the vacuum tightness of the mold, the steel plate surface of the mold plate in the mold body is tightly welded. The steel plate surface is made of Q235 steel plate. The overall size after welding is 17000mm*9640mm*10mm. Maintain pressure after welding: evacuate to absolute vacuum within 10mbar, and the pressure drop is less than 10mbar within 30 minutes after turning off the vacuum pump.

[0071] In this embodiment, a heating layer is evenly distributed on the bottom of the mold plate, and a height adjustment member is provided through the heating layer. The heating component in the heating layer is a copper tube for circulating the heated heat-conducting fluid. The copper tube has a diameter of 12 mm, a wall thickness of 1 mm, and a center distance of 80 ± 5 mm. It is arranged in a serpentine shape on the back of the mold plate, and the length of a single copper tube is within 50 meters. The heating component is wrapped and set in a solidified manner within the structural layer; the structural layer is formed by mixing and solidifying aluminum powder and resin. By arranging copper tube pipelines, a heat-conducting aluminum powder layer, and a thermal insulation layer on the back of the mold plate, the present invention has a heating function that can meet the temperature required for the FRP road panel forming process. The thermal insulation layer is a thermal insulation cotton with tin foil. The use of the heat-conducting aluminum powder layer allows the surface temperature of the mold plate to be uniform to within 5°C. The use of the thermal insulation layer further reduces heat loss, allowing the product area of ​​the FRP road panel preparation mold to be heated to above 90°C, providing temperature protection for the solidification and forming of the FRP road panel. In addition, the present invention raises the mold temperature to above 90°C, which greatly broadens the selectivity of the infusion resin. Not only can room temperature curing resins be selected, but also medium and high temperature curing resins with better performance can be selected. At the same time, the increase in mold temperature can not only shorten the curing time, but also allow the resin to cure after completion on the mold, which not only improves the molding efficiency but also reduces the demolding deformation caused by incomplete curing.

[0072] The mold for preparing the FRP road panel in this embodiment is equipped with an equalizing plate compared to the mold for conventional vacuum infusion FRP road panel. When in use, the equalizing plate is laid between the fiber fabric and the vacuum auxiliary material, and the equalizing plate is used as the "other side mold". The drainage groove provided on the equalizing plate can drain the resin into the fiber fabric, completing the penetration of the resin into the fiber fabric. The use of this mold can overcome the defect of "single-sided light" in the vacuum infusion process, so that the product has a "two-sided light" characteristic. The upper surface of the obtained road panel body is the mold surface with good flatness. It does not need to be polished and repaired as a whole, and can be sprayed to form a sandblasted anti-slip layer. The lower surface is an anti-slip textured surface formed by the patterned equalizing plate, with clear patterns, regular arrangement, and beautiful appearance. Example

[0073] The preparation method of the glass fiber reinforced plastic road slab of this embodiment is completed using the mold for preparing the glass fiber reinforced plastic road slab of the above embodiment 8. The preparation method includes:

[0074] S0. Before manufacturing FRP road panel products, apply release agent on the surface of the mold plate, the surface of the equalizing plate, the surface of the lower baffle and the surface of the pultruded profile of the upper baffle;

[0075] S1. Lay three layers of 1300g / ㎡ glass fiber fabric 5 on the mold in the molding area divided by the inner and outer baffles;

[0076] S2. Lay the connecting strip 6 tightly across the single board along the length of the lower baffle, with a size of 500*300*2mm, so that the two sides of the connecting strip are 240mm long on the glass fiber fabric in the molding area on both sides, and the central 20mm width overlaps with the inner baffle, and fix the connecting strip to the lower baffle with spray glue. Figure 4 As shown;

[0077] S3. Pre-coat a dense film of silicone on both sides of the central 20mm width of the connecting strip. Place an upper retaining strip above the center of the strip and secure it to the strip with double-sided tape. Place eight strips in total. The silicone film prevents resin from seeping into the hinged joints during the infusion process, which could cause the strip to become rigid and unable to fold. The silicone film effectively insulates the epoxy resin and primarily fills the gaps and surface of the strip. The thickness is less than 1mm.

[0078] S4. Continue to lay the glass fiber fabric above the glass fiber fabric in the sub-molding area, and lay 2 layers of glass fiber fabric at the connection belt;

[0079] S5. Continue to lay the glass fiber fabric on top of the glass fiber fabric in the sub-molding area, lay out 3 layers as a whole, press the connecting tape underneath, and expose the upper baffle to cover the connecting tape;

[0080] S6. Place 9 equalizing plates on top of the fiberglass fabric, with the concave pattern facing downward.

[0081] S7. Continue to lay the guide net 9, glue injection tube 7, glue injection seat, glue suction tube, vacuum belt 8 and other auxiliary materials on the top of the pressure plate, and cover with vacuum film. Figure 5 As shown; the mold is then vacuumed and poured with resin;

[0082] S8. Curing the resin at 90°C for 6 hours;

[0083] S9. After the board is solidified, the surface injection auxiliary materials are removed, the upper baffle pultruded profile is removed, the equalizing plate and the product are separated to obtain the FRP road panel. The contact surface between the product and the equalizing plate is formed into a pattern, and the contact surface with the steel mold is formed into a flat surface. Example

[0084] The preparation method of the glass fiber reinforced plastic road panel of this embodiment is the same as that of Example 9 in other steps, except that the pressure equalizing plate of Example 2 is used. Example

[0085] The preparation method of the glass fiber reinforced plastic road panel of this embodiment is the same as that of Example 9 in other steps, except that the pressure equalizing plate of Example 3 is used. Example

[0086] The preparation method of the glass fiber reinforced plastic road panel of this embodiment is the same as that of Example 9 in other steps, except that the pressure equalizing plate of Example 4 is used. Example

[0087] The preparation method of the glass fiber reinforced plastic road panel of this embodiment is the same as that of Example 9 in other steps, except that the pressure equalizing plate of Example 5 is used. Example

[0088] The preparation method of the glass fiber reinforced plastic road panel of this embodiment is the same as that of Example 9 in other steps, except that the pressure equalizing plate of Example 6 is used. Example

[0089] The preparation method of the glass fiber reinforced plastic road panel of this embodiment is the same as that of Example 9 in other steps, except that the pressure equalizing plate of Example 7 is used.

[0090] Different pressure-equalizing plates are used in the preparation of FRP road panels. The pouring time, effect and the state of the pressure-equalizing plates after demoulding are shown in Table 1 below.

[0091] Table 1

[0092] serial number describe Infusion duration and effect State of the pressure plate after demoulding Example 1 1h30min, good immersion normal Example 2 No corners 1h40min, good immersion normal Example 3 Same length 1h25min, slight air pockets on both sides of the middle normal Example 4 8 drainage troughs There is a large area of ​​dry yarn between the drainage grooves normal Example 5 29 drainage troughs 1h30min, good immersion Minor damage Example 6 1500cm long 1h20min, good immersion Slight deformation in the middle Example 7 900cm long 2h, with a large area of ​​dry yarn on both sides normal

[0093] Note: On the same mold, except for the two side veneers, the pressure equalizing plates of Examples 1-7 were placed on the middle 7 veneers in sequence and poured at the same time to obtain comparative data.

[0094] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A pressure balancing plate for preparing a glass fiber reinforced plastic road panel, characterized by: The pressure equalizing plate comprises a main body, one side of which is provided with a concave pattern, and the main body is further provided with a plurality of drainage grooves running through both sides of the main body; the pressure equalizing plate is used to be laid between the fiber fabric and the vacuum auxiliary material when the glass fiber reinforced plastic road panel is formed by the vacuum infusion process, with the concave pattern facing the fiber fabric to apply pressure to the fiber fabric; The drainage grooves include a plurality of longitudinal drainage grooves and a plurality of corner drainage grooves; The longitudinal drainage groove is arranged along the width direction of the pressure equalizing plate body, and a plurality of the longitudinal drainage grooves are arranged at intervals along the longitudinal direction of the pressure equalizing plate body; The angle between the length direction of the corner drainage groove and the width direction of the equalizing plate body is 30-60 degrees; the corner drainage grooves are respectively provided at the four corners of the equalizing plate body; Starting from the width side of the pressure equalizing plate body, a longitudinal drainage groove is provided at equal intervals; the length of the longitudinal drainage groove decreases from the longitudinal drainage groove located in the middle of the pressure equalizing plate body to the longitudinal drainage grooves on both sides; A total of 15-19 longitudinal drainage grooves are provided; the length of the longitudinal drainage groove located in the middle of the equalizing plate body is 0.6-0.7 times the width of the equalizing plate body; the length of the longitudinal drainage groove located at the outermost side of the equalizing plate body is 0.5-0.6 times the width of the equalizing plate body; the length of the longitudinal drainage groove is shortened by equal values ​​from the longitudinal drainage groove located in the middle of the equalizing plate body to the longitudinal drainage grooves on both sides; A corner drainage groove is provided at each corner of the pressure equalizing plate body, and the length of the corner drainage groove is 0.1-0.2 times the width of the pressure equalizing plate body; The width of the longitudinal drainage groove and / or the corner drainage groove is 1-2 mm; the thickness of the pressure equalizing plate body is 3-5 mm.

2. A mold for preparing glass fiber reinforced plastic road panels, characterized by: It comprises a mold body and a pressure equalizing plate for preparing a glass fiber reinforced plastic road panel as claimed in claim 1; The mold body includes a mold plate, an outer rib, and an inner rib; the outer rib and the inner rib are arranged on the upper surface of the mold plate; the inner side surface of the outer rib and the upper surface of the mold plate form a molding area suitable for molding a glass fiber reinforced plastic road panel; the inner rib is arranged in the molding area, and the inner side surface of the outer rib, the upper surface of the mold plate and the side surface of the inner rib form a sub-molding area suitable for molding a single plate of the glass fiber reinforced plastic road panel; the inner rib includes an upper rib and a lower rib, the lower rib is connected to the upper surface of the mold plate, the upper rib is located above the lower rib, and the upper rib and the lower rib are suitable for clamping and fixing the connecting belt of the glass fiber reinforced plastic road panel; The pressure equalizing plate is suitable for being placed above the fiber fabric in the sub-forming area.

3. The mold for preparing a glass fiber reinforced plastic road panel according to claim 2, characterized in that: The pressure balancing plate is a glass fiber reinforced plastic plate, the material of which is a glass fiber reinforced epoxy resin composite material; the upper baffle is a glass fiber reinforced plastic pultruded profile.

4. A method for preparing a glass fiber reinforced plastic road panel, characterized in that: The mold for preparing the glass fiber reinforced plastic road panel according to claim 2 or 3 is used for preparation, and the preparation method comprises: S1. Laying a first fiber fabric layer in the sub-molding area; S2. Lay the connecting tape on the lower baffle along the length direction of the lower baffle, so that the two sides of the connecting tape are laid on the first fiber fabric layer in the sub-molding area on both sides, and fix the connecting tape to the lower baffle; S3. Place the upper bar above the connecting strip and secure the upper bar to the connecting strip; S4. Overlaying a second fiber fabric layer on top of the first fiber fabric layer in the sub-molding area, so that the second fiber fabric layer is docked with the connecting belt; S5. Overlaying a third fiber fabric layer on top of the second fiber fabric layer in the sub-molding area to cover the connecting tape; S6. Laying the equalizing plate above the third fiber fabric layer, with the side of the equalizing plate having the concave pattern facing downward; S7. Laying vacuum auxiliary material above the equalizing plate, sealing the top of the mold, and then evacuating the mold and infusing the resin; S8. Curing and molding the resin to obtain the fiberglass reinforced plastic road panel.

5. The preparation method according to claim 4, characterized in that: The method further includes applying an organic silicone film to the contact areas of the connecting belt and the upper and lower stop bars before laying the connecting belt in step S2.

6. The preparation method according to claim 4, wherein: The connecting belt is fixed to the lower baffle and the upper baffle by means of double-sided adhesive.

7. A glass fiber reinforced plastic road panel prepared by the preparation method according to any one of claims 4 to 6.

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