Three-dimensional protective bamboo composite cover plate

Abstract

Disclosed in the present invention is a three-dimensional protective bamboo composite cover plate. The three-dimensional protective bamboo composite cover plate has a thickness of 20 mm-100 mm, and comprises a bamboo cover plate base body (1) and a protective layer (2); the protective layer (2) is wrapped around the outside of the bamboo cover plate base body (1); the bamboo cover plate base body (1) comprises a plurality of radial bamboo silver units (11) that have not been subjected to kneading or rolling treatment and a plurality of gaps (12); an adhesive body (13) is wrapped around the outside of each radial bamboo silver unit (11); the radial bamboo silver units (11) are arranged in a crisscross manner and are bonded by means of the adhesive body (13); the gaps (12) are formed between at least two radial bamboo silver units (11); the gaps (12) are filled with a protective body (14); and the protective body (14) is integrally connected to the protective layer (2). The three-dimensional protective bamboo composite cover plate has the advantages of high bearing strength, good protective effect, simple structure, etc.

Description

3D Protective Bamboo Composite Cover

[0001] Cross-references to related applications

[0002] This application is based on and claims priority to Chinese patent application filed on January 27, 2025, with application number 202520176379.5 and invention title "Three-dimensional protective bamboo composite cover", the full text of which is incorporated herein by reference as a part of this application. [Technical Field]

[0003] This invention relates to the field of new materials for drainage ditch maintenance covers for roads, cable pipes, etc. in municipal gardens, residential areas, factories, etc., and particularly to a three-dimensional protective bamboo composite cover. [Background Technology]

[0004] Currently, most manhole covers, cable duct covers, and other road surface covers in municipal projects, residential areas, and factories are made of cast iron, cement, or resin composite materials. Cast iron covers are prone to rusting, theft, and rattling when vehicles pass over them, causing significant noise at night and disrupting residents' lives. Cement covers are heavy, difficult to open and close, brittle, not resistant to acid and alkali corrosion, and easily age and break, potentially causing sewer blockages. Resin composite covers, under high temperatures and repeated vehicle traffic, undergo creep, causing the central section to sink and even detach, posing a significant safety hazard. Furthermore, these materials are non-renewable, hindering sustainable development.

[0005] Bamboo is an important forest resource in my country, possessing excellent physical and mechanical properties and a wide range of applications. Furthermore, bamboo has a short growth cycle, maturing in 3-5 years. Regular harvesting of bamboo not only avoids ecological damage but also benefits bamboo growth and the overall environment. Existing technologies include solutions for using bamboo to make manhole covers. One manhole device and its manhole cover include: a panel; at least two reinforcing structures, with the at least two reinforcing structures fixedly connected to the bottom of the panel, each reinforcing structure including at least two spaced reinforcing beams; and side beams, located on both sides of the panel and the at least two reinforcing structures, for connecting the panel and the at least two reinforcing structures. Through long-term research, the applicant discovered that existing bamboo manhole covers, typically represented by this technical solution, are structural reconstituted bamboo materials manufactured according to the industry standard LY / T3194-2020. When this type of reconstituted bamboo board is laid with bamboo bundles or bamboo filaments, it is generally laid in the longitudinal direction. The bamboo bundles or bamboo filaments have a unidirectional structure. When this type of reconstituted bamboo board is used as a cover, the cover is subjected to surface stress. The unidirectional structure is prone to cracking during the pressure-bearing process. Therefore, in order to meet the relevant support strength requirements, the cover of this technical solution needs to be additionally reinforced in addition to the panel, which makes the structure complex. Therefore, existing bamboo manhole covers still have the technical problem of complex structure, which limits the large-scale promotion of bamboo manhole covers in industrial applications. [Summary of the Invention]

[0006] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a three-dimensional protective bamboo composite cover with simple structure and high strength.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0008] A three-dimensional protective bamboo composite cover, the thickness of which is 20mm to 100mm, includes a bamboo cover substrate and a protective layer. The protective layer is wrapped around the bamboo cover substrate. The bamboo cover substrate includes multiple radial bamboo strip units that have not been rolled or pressed and multiple gaps. Each radial bamboo strip unit is wrapped with an adhesive. The radial bamboo strip units are arranged in a crisscross pattern and bonded together with the adhesive. The radial bamboo strip units within the same radial bamboo strip unit layer are arranged in the same direction and bonded together with the adhesive. The gaps are formed between at least two radial bamboo strip units and are filled with a protective body. The protective body is integrated with the protective layer.

[0009] In some embodiments of the present invention, the three-dimensional protective bamboo composite cover also includes a pry bar hole, which is provided on the bamboo cover substrate and facilitates closing or opening the three-dimensional protective bamboo composite cover.

[0010] In some embodiments of the present invention, the three-dimensional protective bamboo composite cover also includes a drainage groove, which penetrates the upper and lower surfaces of the bamboo cover substrate in the thickness direction and facilitates drainage.

[0011] In some embodiments of the present invention, the adhesive is formed by immersing radial bamboo strip units in an adhesive for a preset time, drying them, and then pressing and curing them.

[0012] In some embodiments of the present invention, the moisture content of the radial bamboo strip unit is 8% to 20%, the thickness of the radial bamboo strip unit is 0.5 mm to 3 mm, and the width is 3 mm to 12 mm. Preferably, the thickness of the radial bamboo strip unit is 0.5 mm to 2 mm.

[0013] In some embodiments of the present invention, the bamboo cover substrate is obtained by first pressing the crisscrossing, glued, dried radial bamboo strip units to a preset pressure, then heating them to a preset temperature and curing them for a preset time.

[0014] In some embodiments of the present invention, the protective layer and the protective body are made of the same or different materials; when the materials are the same, the protective layer and the protective body are protective coating structures formed by immersing the bamboo cover substrate in protective coating for a predetermined time; when the materials are different, the protective layer and the protective body are step-by-step integral structures formed by first filling the gaps with the protective body and then wrapping the bamboo cover substrate with the protective layer.

[0015] In some embodiments of the present invention, the bamboo cover substrate is in the shape of a cuboid or a cylinder.

[0016] In some embodiments of the present invention, the bamboo cover substrate is rectangular, and the length of the three-dimensional protective bamboo composite cover is 400mm to 1000mm and the width is 100mm to 800mm.

[0017] In some embodiments of the present invention, the bamboo cover substrate is cylindrical in shape, and the diameter of the three-dimensional protective bamboo composite cover is 400mm to 1000mm.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] The three-dimensional protective bamboo composite cover of the present invention has the following characteristics: First, the surface of the radial bamboo strip units is not subjected to rolling or pressing treatment, which does not damage the strength of the bamboo fiber itself and facilitates the penetration and wrapping of the protective body within the gaps formed during the pressing of the radial bamboo strip units, thereby improving the protective effect of the protective body; Second, the radial bamboo strip units of the cover are arranged in a crisscross pattern, requiring no other reinforcing structure, resulting in greater lateral strength, simpler operation, strong load-bearing capacity under surface stress, and resistance to cracking; Third, the bamboo cover substrate includes multiple gaps formed between at least two radial bamboo strip units, and the gaps are filled with the protective body, which is integrated with the protective layer, so that the protective body inside the bamboo cover substrate and the protective layer wrapped around the bamboo cover substrate are integrated to form a three-dimensional protective effect. The protective layer is not easy to fall off, the protection time is long, and the overall strength is high. [Attached Image Description]

[0020] Figure 1 is a schematic diagram of the three-dimensional structure of the three-dimensional protective bamboo composite cover of the present invention.

[0021] Figure 2 is a schematic diagram of the cross-sectional structure of AA of the three-dimensional protective bamboo composite cover of the present invention.

[0022] Figure 3 is an enlarged view of point B in Figure 2.

[0023] Figure 4 is a schematic diagram of the three-dimensional structure of the bamboo cover substrate of the three-dimensional protective bamboo composite cover of the present invention.

[0024] Figure 5 is a schematic diagram of the left-side structure of the bamboo cover substrate of the three-dimensional protective bamboo composite cover of the present invention.

[0025] Figure 6 is a schematic diagram of the main structure of the bamboo cover substrate of the three-dimensional protective bamboo composite cover of the present invention.

[0026] Figure 7 is a three-dimensional structural schematic diagram of Embodiment 2 of the three-dimensional protective bamboo composite cover of the present invention.

[0027] Figure 8 is a three-dimensional structural schematic diagram of Embodiment 3 of the three-dimensional protective bamboo composite cover of the present invention.

[0028] Figure 9 is a physical image of the bamboo cover substrate (without a protective body) of the three-dimensional protective bamboo composite cover of the present invention.

[0029] The labels in the diagram represent: 1. Bamboo cover substrate; 11. Radial bamboo strip unit; 12. Gap; 13. Adhesive; 14. Protective body; 2. Protective layer; 3. Pry bar hole; 4. Drain groove.

Detailed Implementation Methods

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Unless otherwise specified, all materials or instruments described below are commercially available.

[0031] Example 1:

[0032] Figures 1 to 6 illustrate an embodiment of the three-dimensional protective bamboo composite cover of the present invention. The three-dimensional protective bamboo composite cover of this embodiment includes a bamboo cover substrate 1 and a protective layer 2. The protective layer 2 is wrapped around the bamboo cover substrate 1. The bamboo cover substrate 1 includes a plurality of radial bamboo strip units 11 that have not been rolled or crushed and a plurality of gaps 12. Each radial bamboo strip unit 11 is wrapped with an adhesive 13. The radial bamboo strip units 11 are arranged in a crisscross pattern and are bonded together by the adhesive 13. The gaps 12 are formed between at least two radial bamboo strip units 11. The gaps 12 are filled with a protective body 14, and the protective body 14 is connected to the protective layer 2 as a whole.

[0033] This invention relates to a three-dimensional protective bamboo composite cover. First, the surface of the radial bamboo strip units 11 is not subjected to rolling or pressing treatment, which does not damage the strength of the bamboo fibers themselves and facilitates the penetration and wrapping of the protective body 14 within the gaps 12 outside the radial bamboo strip units 11, thereby improving the protective effect of the protective body 14. Second, the radial bamboo strip units 11 of the cover are arranged in a crisscross pattern, requiring no other reinforcing structures, resulting in greater lateral strength, simpler operation, strong load-bearing capacity under surface stress, and resistance to cracking. Third, the bamboo cover substrate 1 includes multiple gaps 12, which are formed between at least two radial bamboo strip units 11. The gaps 12 are filled with the protective body 14, which is integrated with the protective layer 2. This allows the protective body 14 inside the bamboo cover substrate 1 to combine with the protective layer 2 wrapped around the bamboo cover substrate 1, forming a three-dimensional protective effect. The protective layer 2 is not easy to fall off, provides long-lasting protection, and has high overall strength.

[0034] Furthermore, the radial bamboo strip units 11 can be layered along the vertical direction. At least two adjacent layers of radial bamboo strip units 11 are arranged in a crisscross pattern and bonded together with adhesive 13. Radial bamboo strip units 11 within the same layer are arranged in the same direction or in a crisscross pattern and bonded together with adhesive 13. The radial bamboo strip units 11 can be arranged as single, dispersed pieces or woven into a bamboo curtain.

[0035] Furthermore, in this embodiment, the three-dimensional protective bamboo composite cover also includes a drainage groove 4. The drainage groove 4 penetrates the upper and lower surfaces of the bamboo cover substrate 1 in the thickness direction and facilitates drainage. In this embodiment, the drainage groove 4 is a U-shaped groove.

[0036] Furthermore, in this embodiment, the adhesive 13 is formed by immersing the radial bamboo strip units 11 in the adhesive for a preset time, drying, and then pressing and curing, which helps to improve the overall bonding strength. Preferably, the adhesive 13 is a phenolic resin, which has good bonding effect and weather resistance, thus helping to improve the overall bonding strength. The adhesive 13 is bonded to the surface of the radial bamboo strip units 11; of course, it can also be immersed in the surface layer of the radial bamboo strip units 11.

[0037] Furthermore, in this embodiment, the moisture content of the radial bamboo strip unit 11 is 8% to 20%.

[0038] Furthermore, in this embodiment, the thickness of the radial bamboo strip unit 11 is 0.5mm to 3mm, and the width is 3mm to 12mm. Preferably, the thickness of the radial bamboo strip unit 11 is 0.5mm to 2mm.

[0039] Furthermore, as shown in Figures 4, 5 and 6, in this embodiment, the bamboo cover plate substrate 1 is obtained by first pressing the radial bamboo strip units 11 of the crisscrossing blanks to a preset pressure, then heating them to a preset temperature and curing them for a preset time. This process is convenient and has high production efficiency.

[0040] Furthermore, in this embodiment, the preset temperature is 100℃~165℃.

[0041] Furthermore, in this embodiment, the preset pressure is 10MPa to 30MPa, and the preset time is 30 to 120 minutes.

[0042] Furthermore, in this embodiment, the protective layer 2 and the protective body 14 may be made of the same or different materials;

[0043] When the materials are the same, the protective layer 2 and the protective body 14 are protective coating structures formed by immersing the bamboo cover board substrate 1 in the protective coating for a predetermined time.

[0044] When the materials are different, the protective layer 2 and the protective body 14 are a step-by-step integral structure formed by first filling the gap 12 with the protective body 14 and then wrapping the protective layer 2 around the bamboo cover substrate 1. Preferably, the material of the protective layer 2 and the protective body 14 is polyurea coating. In this case, the protective layer 2 and the protective body 14 are polyurea coating structures formed by immersing the bamboo cover substrate 1 in polyurea coating for a predetermined time. The protective layer 2 and the protective body 14 are formed in one step by immersing the bamboo cover substrate 1 in polyurea coating for a predetermined time, which is convenient to produce and has a good protective effect.

[0045] Furthermore, in this embodiment, the radial bamboo strip units 11 are arranged in a crisscross and disordered manner, so that the gaps 12 between the radial bamboo strip units 11 are randomly distributed in three-dimensional space. Therefore, the protective body 14 located in the gaps 12 and the protective layer 2 form a three-dimensional mesh structure, which further improves the protective effect.

[0046] Furthermore, the bamboo cover substrate 1 is rectangular in shape, and the length of the three-dimensional protective bamboo composite cover is 400mm to 1000mm (500mm in this embodiment), the width is 100mm to 800mm (300mm in this embodiment), and the thickness is 20mm to 100mm (30mm in this embodiment).

[0047] Example 2:

[0048] Figure 7 shows another embodiment of the three-dimensional protective bamboo composite cover of the present invention. The structure of this embodiment is basically the same as that of the first embodiment, except that: this type of bamboo cover does not require drainage, the bamboo cover base 1 is not machined with a U-shaped groove, but is machined with a pry bar hole 3. The pry bar hole 3 is set on the bamboo cover base 1 and is convenient to close or open the three-dimensional protective bamboo composite cover for daily pipeline maintenance and repair.

[0049] Example 3:

[0050] Figure 8 shows another embodiment of the three-dimensional protective bamboo composite cover of the present invention. The structure of this embodiment is basically the same as that of embodiment 2, except that the shape of the cover is different. The bamboo cover base 1 is cylindrical, the diameter of the composite cover is 400mm to 1000mm (800mm in this embodiment), and the thickness is 20mm to 100mm (70mm in this embodiment).

[0051] Example 4:

[0052] The manufacturing method of the three-dimensional protective bamboo composite cover plate in this embodiment, taking the manufacturing of a bamboo cover plate for a trench cover with a length of 500mm, a width of 300mm, and a thickness of 30mm as an example, specifically includes the following steps:

[0053] (1) Select 5-year-old moso bamboo and cut it in the length direction. Each section is 2440mm+10mm long to obtain the original bamboo section.

[0054] (2) Split the original bamboo section into an arc-shaped bamboo unit that retains the green and yellow bamboo, and then process the arc-shaped bamboo unit that retains the green and yellow bamboo into a radial bamboo strip unit 11 with a length of 2440mm, a width of 10mm and a thickness of 1.5mm using a radial bamboo strip splitting machine.

[0055] (3) Carbonize the above-mentioned radial bamboo strip unit 11 at 130℃ for 2 hours to further improve its anti-corrosion and anti-mildew properties, so that its anti-corrosion performance reaches the strong corrosion resistance level I.

[0056] (4) The above-mentioned radial bamboo strip unit 11 is dried with hot air at 100°C until the moisture content is about 10%.

[0057] (5) The dried radial bamboo strip unit is immersed in phenolic resin with a solid content of 29% for 20 minutes under normal pressure to absorb the glue. During the immersion, the glue is kept flowing to ensure the uniformity of the glue. After immersion, the excess adhesive is drained off, and then dried at 60°C until the moisture content of the radial bamboo strip unit 11 is 8% to 20%, thus obtaining the glued and dried radial bamboo strip unit 11.

[0058] (6) The dried radial bamboo strip units 11 after gluing are assembled longitudinally and transversely in a mold of matching size, and pressure is applied at 25 MPa to ensure that the bamboo strip units are fully pressed and bonded together to ensure the subsequent curing and bonding of the adhesive. The longitudinal and transverse assembly refers to the interlacing of at least two adjacent layers of radial bamboo strip units 11. The interlacing is random, and the angle of the interlacing of at least two adjacent layers of radial bamboo strip units 11 is not limited and can be 30°, 60°, 90°, etc., not limited to 90°.

[0059] (7) The blank pressed by the mold is cured at 150°C for 40 minutes. After curing, the mold is removed to obtain the bamboo cover blank. In other embodiments, a curing time of 30 to 120 minutes can achieve similar technical effects.

[0060] (8) The bamboo cover blank is first machined to meet the length, width and thickness dimensions. In this embodiment, the bamboo cover is machined to be 500mm long, 300mm wide and 30mm thick. Then, it is shaped and grooved to obtain the bamboo cover base 1. Grooving is done so that the bamboo cover can drain water quickly and can be easily opened for daily pipeline maintenance and repair in the trench.

[0061] In this embodiment, the shape is a regular cuboid (as shown in the product of embodiment one) and the surface does not require separate scoring treatment. The groove is generally a U-shaped groove to meet the requirements of the cover's size, appearance, drainage and easy handling.

[0062] (9) The machined bamboo cover substrate 1 is subjected to pressure impregnation with a high waterproof, high weather-resistant and high elastic polyurea coating to penetrate, combine and wrap to form an integrated protective layer for overall protection treatment. The treatment is carried out for 10 minutes under a pressure of 0.6MPa to further improve the penetration depth of the protective treatment and ensure that the treatment is in place in all aspects, so as to obtain a three-dimensional protective bamboo composite cover (product of Example 1).

[0063] In this embodiment, a three-dimensional protective bamboo composite cover is manufactured by using radial bamboo strips that retain both the green and yellow parts of the bamboo, through a combination of multiple technologies including carbonization, drying, gluing, post-glue drying, pressing, thermosetting, machining, and surface protection treatment. The specific process flow of this embodiment is as follows: cutting the raw bamboo → splitting the raw bamboo segments → radial splitting → carbonizing the radial bamboo strip unit 11 → drying the radial bamboo strip unit 11 → impregnating with phenolic resin → post-glue drying → longitudinal and transverse assembly → pressing → thermosetting → machining → integrated surface protection treatment → three-dimensional protective bamboo composite cover.

[0064] Example 5:

[0065] The manufacturing method of the three-dimensional protective bamboo composite cover plate in this embodiment, taking the manufacturing of a bamboo cover plate for a well cover with a diameter of 800mm and a thickness of 70mm as an example, specifically includes the following steps:

[0066] (1) Select 5-year-old moso bamboo and cut it in the length direction. Each section is 2440mm±10mm to obtain the original bamboo section.

[0067] (2) Split the original bamboo section into an arc-shaped bamboo unit that retains the green and yellow bamboo, and then process the arc-shaped bamboo unit that retains the green and yellow bamboo into a radial bamboo strip unit 11 with a length of 2440mm, a width of 10mm and a thickness of 1.5mm using a radial bamboo strip splitting machine.

[0068] (3) The above-mentioned radial bamboo strip unit 11 is dried with hot air at 100°C until the moisture content is about 10%.

[0069] (4) The dried radial bamboo strip unit 11 is immersed in phenolic resin with a solid content of 29% for 20 minutes under normal pressure to absorb the glue. During the immersion, the glue is kept flowing to ensure the uniformity of the glue. After immersion, the excess adhesive is drained off, and then dried at 60°C until the moisture content of the radial bamboo strip unit 11 is 8% to 20%, thus obtaining the glued and dried radial bamboo strip unit 11.

[0070] In other embodiments, the sizing treatment can be carried out under a pressure of 0.2 to 0.8 MPa for 10 to 15 minutes to achieve the same or similar technical effects.

[0071] (5) The dried radial bamboo strip units 11 after gluing are assembled longitudinally and transversely in a mold of matching size, and pressure is applied at 25 MPa to ensure that the radial bamboo strip units 11 are fully pressed and bonded to ensure the subsequent curing and bonding of the adhesive.

[0072] (6) The blank pressed by the mold is cured at 150°C for 80 minutes. After curing, the mold is removed to obtain the bamboo cover blank.

[0073] (7) The bamboo cover blank is first machined to measure its diameter and thickness. In this embodiment, the bamboo cover is machined to a diameter of 800 mm and a thickness of 70 mm. Then, it is shaped and drilled to obtain the bamboo cover base 1 as shown in Figure 9. The drilling is to create pry holes 3 on the bamboo cover to facilitate the opening of the cover with a pry bar for daily pipeline maintenance and repair.

[0074] The product in this embodiment is cylindrical (as shown in the product of embodiment three) and does not require separate scoring on the surface. The pry bar hole 3 is generally a quincunx-shaped hole to meet the requirements of the cover plate's size, appearance, and ease of handling.

[0075] (8) The machined bamboo cover substrate 1 is soaked in a polyurea coating (commercially available) with high waterproof, high weather resistance and high elasticity to penetrate, combine and wrap the integrated protective layer 2 and protective body 14 to carry out overall protection treatment. The treatment needs to be done in all aspects to obtain a three-dimensional protective bamboo composite cover (product of Example 3).

[0076] In other embodiments, protective treatment is carried out under pressure impregnation at a pressure of 0.6 to 1.2 MPa, which can be completed in a shorter time and achieve the same or similar technical effects.

[0077] In this embodiment, a three-dimensional protective bamboo composite cover is manufactured by using radial bamboo strips that retain both the green and yellow parts of the bamboo, through a combination of multiple technologies including gluing, post-gluing drying, pressing, thermosetting, machining, and surface protection treatment. The specific process flow of this embodiment is as follows: cutting the raw bamboo → splitting the raw bamboo segments → radial splitting → drying the radial bamboo strip unit 11 → impregnating with phenolic resin → post-gluing drying → longitudinal and transverse assembly → pressing → thermosetting → machining → integrated surface protection treatment → three-dimensional protective bamboo composite cover.

[0078] Comparative Example 1:

[0079] The manufacturing method of this comparative example of a three-dimensional protective bamboo composite cover: Taking the manufacture of a bamboo cover for a manhole cover with a diameter of 800mm and a thickness of 70mm as an example, the specific steps include:

[0080] (9) Select 5-year-old moso bamboo and cut it in the length direction. Each section is 2440mm±10mm to obtain the original bamboo section.

[0081] (10) Split the original bamboo section into an arc-shaped bamboo unit that retains the green and yellow bamboo, and then process the arc-shaped bamboo unit that retains the green and yellow bamboo into a radial bamboo strip unit 11 with a length of 2440mm, a width of 10mm and a thickness of 1.5mm using a radial bamboo strip splitting machine.

[0082] (11) The above-mentioned radial bamboo strip unit 11 is dried with hot air at 100°C until the moisture content is about 10%.

[0083] (12) The dried radial bamboo strip unit 11 is immersed in phenolic resin with a solid content of 29% for 20 minutes under normal pressure to absorb the glue. During the immersion, the glue is kept flowing to ensure the uniformity of the glue. After immersion, the excess adhesive is drained off, and then dried at 60°C until the moisture content of the radial bamboo strip unit 11 is 8% to 20%, thus obtaining the glued and dried radial bamboo strip unit 11.

[0084] In other comparative examples, the sizing treatment can be carried out under a pressure of 0.2 to 0.8 MPa for 10 to 15 minutes to achieve the same or similar technical results.

[0085] (13) The dried radial bamboo strip units 11 after gluing are longitudinally assembled in a mold of matching size and pressure is applied at a pressure of 25 MPa to ensure that the radial bamboo strip units 11 are fully pressed and bonded together to ensure the subsequent curing and bonding of the adhesive. Longitudinal assembly refers to the laying of the radial bamboo strip units 11 along the longitudinal direction (in the same direction).

[0086] (14) The blank pressed by the mold is cured at 150°C for 80 minutes. After curing, the mold is removed to obtain the bamboo cover blank.

[0087] (15) The bamboo cover blank is first machined to measure its diameter and thickness. The bamboo cover in this comparative example is machined to a diameter of 800 mm and a thickness of 70 mm. Then, it is shaped and drilled to obtain the bamboo cover base 1. The drilling is to make pry holes 3 in the bamboo cover to facilitate the opening of the cover with a pry bar for daily pipeline maintenance and repair.

[0088] The comparative product is cylindrical in shape (as shown in Example 3) and does not require separate scoring on the surface. The pry bar hole 3 is generally a quincunx-shaped hole to meet the requirements of cover size, appearance and easy handling.

[0089] (16) Use a highly waterproof, highly weather-resistant, and highly elastic polyurea coating (commercially available) to penetrate, combine, and wrap the machined bamboo cover substrate 1 under normal pressure to form an integrated protective layer 2 and a protective body 14 for overall protection treatment. The treatment needs to be done in all aspects to obtain a three-dimensional protective bamboo composite cover.

[0090] In this comparative example, a three-dimensional protective bamboo composite cover was manufactured by using radial bamboo strips that retain both the green and yellow parts of the bamboo, through a combination of multiple technologies including gluing, post-gluing drying, pressing, thermosetting, machining, and surface protection treatment. The specific process flow of this comparative example is as follows: cutting the raw bamboo → splitting the raw bamboo segments → radial splitting → drying the radial bamboo strip unit 11 → impregnating with phenolic resin → post-gluing drying → longitudinal assembly → pressing → thermosetting → machining → integrated surface protection treatment → three-dimensional protective bamboo composite cover.

[0091] In this comparative example, the radial bamboo strip units are longitudinally assembled after drying with glue. Since they are not subjected to unidirectional force when used as cover plates, but rather to surface force, the cover plates are very prone to cracking during the load-bearing process, which poses a significant safety hazard.

[0092] Performance tests were conducted on the composite cover plates of Example 5 and Comparative Example 1. It was found that the overall mechanical properties of Example 5 were better than those of Comparative Example 1, specifically in the following aspects: a significant increase in transverse bending strength: the transverse bending strength of the longitudinally and transversely assembled three-dimensional protective bamboo composite cover plate of Example 5, with the same cross-section and thickness (20mm thick conventional test specimen), was more than 50% higher than that of the longitudinally assembled three-dimensional protective bamboo composite cover plate of Comparative Example 1. The average transverse bending strength of the product specimen of Example 5 reached 100MPa, while the average transverse bending strength of the product specimen of Comparative Example 1 was only about 50MPa. This indicates that when the product of the present invention is used as a cover plate, a product with non-unidirectional force and surface load-bearing requirements, the safety performance will be greatly improved.

[0093] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention, or modify them into equivalent embodiments, without departing from the scope of the present invention. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention, without departing from the scope of the present invention, should fall within the protection scope of the present invention.

Claims

A three-dimensional protective bamboo composite cover plate, the thickness of the three-dimensional protective bamboo composite cover plate is 20mm-100mm, characterized in that: The invention includes a bamboo cover substrate (1) and a protective layer (2). The protective layer (2) is wrapped around the bamboo cover substrate (1). The bamboo cover substrate (1) includes multiple radial bamboo strip units (11) that have not been rolled or crushed and multiple gaps (12). Each radial bamboo strip unit (11) is wrapped with an adhesive (13). The radial bamboo strip units (11) are arranged in a crisscross pattern and are bonded together by the adhesive (13). The gaps (12) are formed between at least two radial bamboo strip units (11). The gaps (12) are filled with a protective body (14). The protective body (14) is connected to the protective layer (2) as a whole. The three-dimensional protective bamboo composite cover plate according to claim 1, characterized in that: The three-dimensional protective bamboo composite cover also includes a pry bar hole (3), which is set on the bamboo cover base (1) and facilitates the closing or opening of the three-dimensional protective bamboo composite cover. The three-dimensional protective bamboo composite cover plate according to claim 1, characterized in that: The three-dimensional protective bamboo composite cover also includes a drain groove (4), which penetrates the upper and lower surfaces of the bamboo cover substrate (1) and facilitates drainage. The three-dimensional protective bamboo composite cover plate according to claim 1, characterized in that: The adhesive (13) is formed by immersing the radial bamboo strip unit (11) in the adhesive for a preset time, drying it, and then pressing and curing it. The three-dimensional protective bamboo composite cover plate according to claim 4, characterized in that: The moisture content of the radial bamboo strip unit (11) is 8% to 20%; the thickness of the radial bamboo strip unit (11) is 0.5 mm to 3 mm, and the width is 3 mm to 12 mm. The three-dimensional protective bamboo composite cover plate according to claim 1, characterized in that: The bamboo cover substrate (1) is obtained by first pressing the radially arranged bamboo strip units (11) to a preset pressure, then heating them to a preset temperature and curing them for a preset time. The three-dimensional protective bamboo composite cover plate according to any one of claims 1 to 6, characterized in that: The protective layer (2) and the protective body (14) may be made of the same or different materials; When the materials are the same, the protective layer (2) and the protective body (14) are protective coating structures formed by immersing the bamboo cover board substrate (1) in the protective coating for a predetermined time; When the materials are different, the protective layer (2) and the protective body (14) are a step-by-step integral structure formed by first filling the gap (12) with the protective body (14) and then wrapping the protective layer (2) around the bamboo cover board substrate (1). The three-dimensional protective bamboo composite cover plate according to any one of claims 1 to 6, characterized in that: The bamboo cover substrate (1) is in the shape of a cuboid or cylinder. The three-dimensional protective bamboo composite cover plate according to claim 8, characterized in that: The bamboo cover substrate (1) is rectangular in shape, and the length of the three-dimensional protective bamboo composite cover is 400mm to 1000mm and the width is 100mm to 800mm. The three-dimensional protective bamboo composite cover plate according to claim 8, characterized in that: The bamboo cover substrate (1) is cylindrical in shape, and the diameter of the three-dimensional protective bamboo composite cover is 400mm to 1000mm.

Images