Bamboo grid

Abstract

The utility model discloses a bamboo grid, and belongs to the technical field of desertification control engineering. The bamboo checks are square bamboo checks formed by connecting two L-shaped or four linear bamboo sand barriers end to end; the side length of each bamboo grid is 500-2000mm; the bamboo sand barrier is of a warp and weft interwoven net-shaped structure composed of weaving lines and bamboo sheets. The length of each bamboo sheet ranges from 200 mm to 600 mm; the length-to-thickness ratio of the bamboo sheets is (100: 1)-(500: 1); a gap is formed between every two adjacent bamboo sheets, and the width of each gap is 0.2-2.2 times that of each bamboo sheet. The bamboo sheets are prepared by sectioning and processing bamboo tubes in the radial direction or the chordwise direction. According to the utility model, the three elements of the size of the bamboo grid unit, the gap width of the bamboo sheets and the embedding depth are synergistically optimized, so that a three-dimensional sand stabilization network with a gradient wind resistance effect is constructed, and a long-acting sand stabilization system with strong environmental adaptability is formed.

Description

Technical Field

[0001] This utility model relates to the field of desertification control engineering technology, and in particular to a bamboo grid. Background Technology

[0002] Sand barriers are a key technology for desertification control, and their material selection and performance optimization directly affect sand fixation effectiveness and ecological restoration efficiency. Straw checkerboard barriers (also known as "straw checkerboard sand barriers") are an ecological engineering method used for windbreak and sand fixation, and for combating desertification. They are mainly applied to deserts or sandy edges in arid and semi-arid regions. They are typically made of straw such as wheat straw, rice straw, and reeds, bound into checkerboard shapes and partially buried in the sand. Straw checkerboard barriers are generally 1m×1m or 2m×2m in size, forming a mesh structure that effectively fixes shifting sand dunes, preventing sand particles from moving with the wind; reduces surface moisture evaporation, improves the local microclimate; creates conditions for subsequent plant growth, promotes ecological restoration, and has advantages such as readily available materials, low cost, and natural biodegradability. However, straw checkerboard barriers have the following disadvantages:

[0003] (1) Limited durability, requiring regular maintenance;

[0004] The materials used for straw checkerboards (wheat straw, rice straw, etc.) will naturally decompose and generally only last for 3 to 5 years, after which they need to be replaced. In areas with strong winds and sandstorms, some straw checkerboards may be overturned or buried by sand, resulting in a decrease in their protective effect.

[0005] (2) It relies on manual labor, and large-scale promotion is costly;

[0006] The laying of straw checkerboards mainly relies on manual labor, which is labor-intensive and inefficient in the desert environment.

[0007] Although the cost of a single installation is low, long-term maintenance (such as replanting or replacement) will increase the overall cost.

[0008] (3) Due to material limitations, supply is insufficient in some areas;

[0009] Straw checkerboard grids require large quantities of plant stalks such as wheat straw and reeds, but in some severely desertified areas, these materials may be in short supply and need to be transported from other regions, increasing costs. If chemical materials (such as plastic mesh) are used as substitutes, it may lead to environmental pollution problems.

[0010] (4) A single measure has limited effect and needs to be combined with other methods;

[0011] Straw checkerboard primarily serves a short-term sand-fixing function. Without subsequent vegetation restoration (such as planting drought-resistant plants), the sand dunes may shift again. In extremely arid areas, relying solely on straw checkerboards is insufficient for long-term dune stabilization; it must be combined with irrigation, sand barriers, and vegetation integration measures.

[0012] (5) Ecological impact;

[0013] If the straw used contains pesticide residues (such as some farmland straw), it may affect sandy microorganisms and small animals. Utility Model Content

[0014] In view of this, the present invention provides a bamboo grid, the main purpose of which is to provide a new material and structure for desertification control that is high in strength, good in toughness, and can be mass-produced by machinery.

[0015] This utility model provides a bamboo grid, which is formed by connecting two L-shaped or four straight bamboo sand barriers end to end to form a square-shaped bamboo grid; the side length of the bamboo grid is 500~1000mm;

[0016] The bamboo sand barrier is a mesh structure composed of woven threads and thin bamboo sheets, with the bamboo sheets arranged in parallel along the longitudinal direction; the woven threads extend perpendicularly to the bamboo sheets, and there is at least one woven thread on each bamboo sheet.

[0017] The length of the bamboo slabs is 200~600mm;

[0018] The length-to-thickness ratio of bamboo slabs is (100:1)~(500:1);

[0019] There are gaps between adjacent bamboo slabs, and the width of the gaps is 0.2 to 2.2 times the width of the bamboo slabs.

[0020] According to the aforementioned bamboo grid, the buried length of the bamboo slabs in the bamboo grid is 40 to 50% of the length of the bamboo slabs.

[0021] According to the aforementioned bamboo grid, the bamboo sheet is prepared by radially cutting bamboo tubes; the cross-section of the bamboo sheet is fan-shaped; the side of the bamboo sheet is an outer arc surface, an inner arc surface, and a side plane between the outer arc surface and the inner arc surface; the outer arc surface and / or the inner arc surface face the direction of extension of the braiding thread.

[0022] In the cross-section of the bamboo sheet, the distance between the two farthest endpoints of the outer arc surface is the thickness b, and the distance between the endpoint where the side plane meets the outer arc surface and the endpoint where the side plane meets the inner arc surface is the width w.

[0023] The width-to-thickness ratio of bamboo slabs is (5:1) to (25:1).

[0024] Furthermore, the thickness of the bamboo slab is 0.8~4.0mm.

[0025] Furthermore, the outer and / or inner curved surfaces of all the bamboo sheets in the bamboo barrier face the same direction.

[0026] Furthermore, the outer and / or inner arc surfaces of adjacent bamboo sheets in the bamboo sand barrier face opposite directions.

[0027] According to the aforementioned bamboo grid, bamboo sheets are prepared by cutting bamboo tubes along the tangential direction;

[0028] The sides of the bamboo sheet are an outer cut surface, an inner cut surface, and a side plane between the outer cut surface and the inner cut surface; the outer arc surface and / or the inner arc surface face the direction of extension of the braided thread;

[0029] In the cross-section of a bamboo sheet, the vertical distance between the outer and inner cutting surfaces is the thickness b, and the distance between the two ends of the outer cutting surface is the width w.

[0030] The width-to-thickness ratio of bamboo slabs is (5:1) to (25:1).

[0031] According to the aforementioned bamboo grid, the braiding thread is either hemp rope or cotton rope. When there are two braiding threads, the gap width between adjacent braiding threads in the horizontal direction is 10~30cm.

[0032] According to the aforementioned bamboo grid, the surface of the bamboo sheet is coated with a UV-resistant coating with a thickness of 50~100nm.

[0033] Based on the aforementioned bamboo grid, the length of the bamboo slabs is 300~500mm.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) This utility model constructs a three-dimensional sand-fixing network with gradient wind-blocking effect by synergistically optimizing the three elements of bamboo grid unit size, bamboo sheet gap width and burial depth, forming a long-term sand-fixing system with strong environmental adaptability.

[0036] (2) This utility model achieves optimal elastic deformation capacity by precisely controlling the range of geometric parameters of the bamboo sheet, while maintaining the bending strength of natural bamboo. On the one hand, the bamboo sheet is easier to bend than break under strong winds, which can disperse wind pressure, extend service life, and maintain the integrity of the sand-fixing structure for a long time. On the other hand, the elastic bamboo sheet will generate slight vibrations in the wind, which may further weaken the near-surface wind speed through turbulence and reduce the initiation of sand particles. In addition, when the bamboo sheet is implanted into the sand layer in a specific arrangement, its unique fan-shaped cross-section and elastic mechanical properties work together to effectively block the flow of sand particles and form a durable sand-fixing network, which is suitable for the application of sand-fixing materials in desertification control projects.

[0037] (3) Bamboo sand barriers made from fan-shaped bamboo sheets have a good effect on windbreak and sand fixation. Compared with rectangular bamboo sheets, the inclined windward surface of the fan-shaped bamboo sheets guides the airflow to deflect gently, causing sand particles to slide off the surface and reduce accumulation. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the structure of a bamboo tube cut radially.

[0039] Figure 2 A schematic diagram of the three-dimensional structure of bamboo thin sheets prepared by radial slicing;

[0040] Figure 3 A transverse cross-sectional view of a bamboo sheet prepared by radial cutting;

[0041] Figure 4 A schematic diagram of the three-dimensional structure of a bamboo sand barrier;

[0042] Figure 5 A schematic diagram of the three-dimensional structure of another type of bamboo sand barrier;

[0043] Figure 6 This is a schematic diagram of the structure of a bamboo tube cut along its tangential direction.

[0044] Figure 7 A schematic diagram of the three-dimensional structure of bamboo thin sheets prepared by tangential sectioning.

[0045] Explanation of reference numerals in the attached figures:

[0046] 100. Bamboo sheet; 101. Outer curved surface; 102. Inner curved surface; 103. Side plane; 104. Outer cut surface; 105. Inner cut surface;

[0047] 200. Braided yarn. Detailed Implementation

[0048] To make the technical problem to be solved, the technical solution and advantages of this utility model clearer, the following will be described in conjunction with the accompanying drawings. Figures 1 to 7 The technical solution of this utility model is clearly and completely described in conjunction with specific embodiments.

[0049] This utility model provides a bamboo grid.

[0050] The bamboo grid is formed by connecting two L-shaped or four straight bamboo barriers end to end to form a square-shaped bamboo grid; the side length of the bamboo grid is 500~1000mm;

[0051] The bamboo sand barrier is a mesh structure composed of woven threads 200 and bamboo sheets 100, with the bamboo sheets 100 arranged in parallel along the longitudinal direction; the woven threads 200 extend perpendicularly to the bamboo sheets 100, and at least one woven thread 200 is provided on the bamboo sheets 100.

[0052] The length is the distance from one end to the other in the extending direction of the bamboo sheet 100.

[0053] The length of the bamboo sheet 100 is 200~600mm; preferably, the length of the bamboo sheet is 300~500mm.

[0054] The length-to-thickness ratio of bamboo slabs is (100:1)~(500:1);

[0055] There is a gap between adjacent bamboo slabs 100, and the gap width is 0.2 to 2.2 times the width of the bamboo slab.

[0056] Furthermore, the embedment length of the bamboo sheet 100 in the bamboo grid is 40-50% of the length of the bamboo sheet 100, and the embedment length is the length buried in the sand layer.

[0057] Furthermore, the braided thread 200 is either hemp rope or cotton rope. When there are two braided threads 200, the gap width between adjacent braided threads 200 in the horizontal direction is 10~30cm.

[0058] Bamboo sheets 100 are prepared by cutting bamboo tubes radially or tangentially. The outer and / or inner arc surfaces of all bamboo sheets in the bamboo sand barrier face the same direction; or, the outer and / or inner arc surfaces of adjacent bamboo sheets in the bamboo sand barrier face opposite directions.

[0059] The first type of bamboo sheet 100 structure: The bamboo sheet 100 is prepared by radially slicing bamboo tubes, such as... Figures 1 to 3 As shown; the cross-section of the bamboo sheet 100 is fan-shaped; the side surface of the bamboo sheet 100 consists of an outer arc surface 101, an inner arc surface 102, and a side plane 103 between the outer arc surface 101 and the inner arc surface 102; in the cross-section of the bamboo sheet 100, the distance between the two farthest endpoints of the arc of the outer arc surface 101 is the thickness b, and the distance between the endpoint of the side plane 103 that connects to the outer arc surface 101 and the endpoint of the side plane 103 that connects to the inner arc surface 102 is the width w. The width-to-thickness ratio of the bamboo sheet is (5:1) to (25:1). The thickness of the bamboo sheet 100 is 0.8 to 4.0 mm.

[0060] The outer arc surface 101 and / or the inner arc surface 102 face the extension direction of the braided thread 200. Specifically, this can be divided into the following two cases:

[0061] In the bamboo sand barrier, the outer arc surface 101 and / or inner arc surface 102 of all bamboo sheets 100 face the same direction; the outer arc surface 101 and / or inner arc surface 102 of adjacent bamboo sheets 100 face opposite directions.

[0062] The following provides an example 1 of the present invention: a sand barrier grid formed by bamboo sheet 100, and a comparative example 1: a sand barrier grid formed by straw.

[0063] Among them, the modulus of elasticity and bending strength were tested in accordance with the "Test Methods for Physical and Mechanical Properties of Bamboo (GB / T 15780~1995)", and the maximum bending moment and bending stress were tested using the uniaxial cantilever beam bending stress test method.

[0064] Example 1: A sand barrier grid is formed using bamboo sheets 100. The bamboo sheets 100 are dried to a moisture content of 8-30%. Two weaving lines 200 are set on the bamboo sheets 100. The weaving lines 200 are cotton ropes with a diameter of 2mm. The bamboo sheets 100 are woven into a bamboo sand barrier curtain. The outer arc surface 101 and / or the inner arc surface 102 face the extension direction of the weaving lines 200. The outer arc surface 101 and / or the inner arc surface 102 of all bamboo sheets 100 face the same direction. The length of the bamboo sheet 100 is 500mm, the width w is 10±2mm, the thickness b is 2mm, the distance between two adjacent bamboo sheets 100 is 5±2mm, the size of the sand barrier grid is 1000mm×1000mm, the length of the bamboo sheet 100 inserted into the sand layer is 250±30mm, and the length of the bamboo sheet 100 exposed from the sand layer is 250±30mm.

[0065] Comparative Example 1:

[0066] The straw is used to form a sand barrier grid. The straw has a diameter of 5±2mm and is cut into 500mm long sections. Cotton rope with a diameter of 2mm is used to weave the straw into a straw curtain with a gap width of 5±2mm between the straws. The straw curtain is then inserted into the ground. The size of the straw grid is 1000×1000mm.

[0067] The basic mechanical properties of bamboo veneer 100 and rice straw are shown in Table 1:

[0068] Table 1

[0069]

[0070] The data shows that the initial interception efficiency of the straw checkerboard in Comparative Example 1 was 65-70%, but severe bending led to gap closure, and the structure completely failed after fracture. The bamboo checkerboard made of bamboo sheets in Example 1 reduced the air permeability to 26.7%, enhanced turbulence by 15-20%, and achieved an interception efficiency of 90-100%. The bamboo sheets in Example 1 possess higher rigidity and deformation resistance, effectively resisting wind and sand impact and sand layer pressure, preventing structural damage. The bamboo insertion depth (25±3 cm) is equal to the exposed portion, forming a symmetrical support system with stronger anti-overturning ability; straw, due to its soft material, is prone to tilting or displacement after insertion. Through the high mechanical properties, precise structural design, and environmental adaptability of bamboo sheets, the problems of deformation, air permeability failure, and poor durability of straw sand barriers were solved, achieving efficient, stable, and sustainable sand fixation. The high mechanical properties and safety factor of bamboo sand barriers significantly extend their service life and reduce maintenance frequency; straw sand barriers, due to rapid failure, require frequent reconstruction, resulting in higher overall costs. In addition, bamboo is a renewable resource, and its processing is low-carbon and environmentally friendly, which is highly consistent with the ecological goals of desertification control.

[0071] The sand-blocking effects of bamboo slabs 100 and rice straw are shown in Table 2:

[0072] Table 2

[0073]

[0074] The data shows that straw and bamboo grids are ineffective at blocking sand, with a structural stability of 90-100%. They are suitable for short-term emergency situations, low wind speed areas (<8m / s), long-term projects, and areas with strong winds and sandstorms (>10m / s). Compared to straw, bamboo sheets (100%) have a much better sand-blocking effect.

[0075] Next, the technical effects of the geometric parameters of bamboo sheet 100 will be demonstrated through experimental results:

[0076] The width-to-thickness ratio of the bamboo sheet 100 was kept constant (the width-to-thickness ratio was controlled at 8 in the experiment), and the change in length-to-thickness ratio was studied. Six examples and one comparative example were used in the experiment. The length of the bamboo sheet 100 was kept constant at 600 mm in the experiment, and the outer arc surface 101 and / or inner arc surface 102 of all bamboo sheets 100 were oriented in the same direction. The specific parameters (thickness, width and length) are set as shown in Table 3. At a wind speed of 20 m / s and a spacing of 40% of the width of the bamboo sheet 100, wind tunnel tests were used to study the performance of the bamboo sheet 100 applied to sand barriers. The length of the bamboo sheet 100 inserted into the sand layer was 300 ± 30 mm, and the length of the bamboo sheet 100 exposed in the sand layer was 300 ± 30 mm. Its bending stress, deflection and sand-blocking efficiency are shown in Table 3.

[0077] Material parameters: Elastic modulus E = 12.5 GPa, tensile strength σ b =128MPa;

[0078] Environmental parameters: wind speed v = 20 m / s, air density ρ = 1.225 kg / m³;

[0079] Calculation formula:

[0080] Air permeability: η = [s / (s+b)]²;

[0081] Where s is the gap width between adjacent bamboo slabs, and b is the width of the bamboo slab;

[0082] Wind load: F=0.5ρv²C d ·(L·b);

[0083] Among them, C d is the drag coefficient; L is the length of the bamboo sheet exposed in the sand layer, that is, the distance from the surface of the sand layer to the top, which is half the length of the bamboo sheet, 300mm;

[0084] Bending stress: σ = 6FL / (bw²);

[0085] Deflection: δ = 4FL³ / (Ebw³);

[0086] Safety factor: n = σ b / σ;

[0087] Sand-blocking efficiency: E 阻 =η(1-η)(1-δ / 300).

[0088] Table 3

[0089]

[0090] The data shows that Example 3 meets safety standards, but its sand-blocking efficiency is significantly lower than that of the thicker examples, requiring a balance between cost and performance requirements. Example 2 has a safety factor of 23.2 and a sand-blocking efficiency of 0.070, indicating a critical structural safety, suitable for low-risk environments. Examples 4-6 show the best overall performance: safety far exceeds the safety threshold (>10); sand-blocking efficiency is close to the theoretical peak; material efficiency: moderate thickness avoids redundancy. Bamboo sheet sand barriers within the length-to-thickness ratio range of 270~330 combine high wind resistance, high sand-blocking efficiency, and reasonable cost, making them suitable for desertification control projects. Comparative Example 2's thickness is too small, resulting in excessive bending stress, a low safety factor, and deflection exceeding 300mm, making the sand-blocking efficiency uncalculated according to the formula, leading to structural failure. Example 7's thickness is too large, resulting in an excessively high safety factor, far exceeding requirements ("excessive"), and material redundancy significantly increases costs, making it uneconomical in engineering. The failure of Comparative Example 2 and the excess of Example 7 highlight the need for strict control of design parameters and dynamic optimization based on actual wind and sand conditions.

[0091] This study investigated the effect of varying length-to-thickness and width-to-thickness ratios of bamboo sheet 100 on its performance in sand barriers. Five implementation examples and two comparative examples were used in the experiment. The width of the bamboo sheet 100 remained constant at 20 mm, and the outer arc surface 101 and / or inner arc surface 102 of all bamboo sheets 100 faced the same direction. Specific parameters (thickness, width, and length) were set as shown in Table 4. At a wind speed of 20 m / s, the spacing between the bamboo sheets 100 was 40% of the bamboo sheet width, the length of the bamboo sheet 100 inserted into the sand layer was half its length, and the length of the bamboo sheet 100 exposed above the sand layer was half its length. Wind tunnel tests were conducted to study the performance of the bamboo sheet 100 in sand barriers, and its performance (bending stress, deflection, safety factor, and sand-blocking efficiency) is also shown in Table 4.

[0092] Table 4

[0093]

[0094] The data shows that the width-to-thickness ratio and length-to-thickness ratio together determine the wind resistance of bamboo veneers: as the width-to-thickness ratio decreases (thickness increases) and the length-to-thickness ratio decreases (thickness increases or length decreases), the bending stress decreases significantly.

[0095] Examples 8-9 (width-to-thickness ratio 20-25, thickness 0.8-1.0 mm): safety factor 23.2 (critical safety), suitable for low-risk environments; Example 12 (width-to-thickness ratio 5, thickness 4.0 mm): safety factor 256.0, sand-blocking efficiency 0.086, but material cost is high. Examples 10-11 (width-to-thickness ratio 10-12.5, thickness 1.6-2.0 mm, length-to-thickness ratio 300-375) have the best overall performance: safety far exceeds the safety threshold (>10); sand-blocking efficiency: 0.083-0.085, close to the theoretical peak; material efficiency: moderate thickness, avoiding redundancy.

[0096] Bamboo sheet sand barriers, within a width-to-thickness ratio range of (10:1) to (12.5:1), achieve an optimal balance between safety (safety factor > 40), sand-blocking efficiency (0.083~0.085), and material economy. They combine high wind resistance, high sand-blocking efficiency, and reasonable cost, making them suitable for desertification control projects. The excess in Comparative Example 3 and the failure warning in Comparative Example 4 necessitate strict control over the coordinated design of the width-to-thickness ratio and length-to-thickness ratio, and dynamic optimization based on actual wind and sand conditions.

[0097] This invention achieves optimal elastic deformation capacity by precisely controlling the geometric parameter range of bamboo sheets 100, while maintaining the bending strength of natural bamboo. On one hand, under strong winds, the bamboo sheets 100 are more prone to bending rather than breaking, thus dispersing wind pressure, extending service life, and maintaining the integrity of the sand-fixing structure over the long term. On the other hand, the elastic bamboo sheets 100 generate minute vibrations in the wind, potentially further weakening near-surface wind speeds through turbulence and reducing sand particle initiation. Furthermore, when the bamboo sheets 100 are implanted into the sand layer in a specific arrangement, their unique fan-shaped cross-section and elastic mechanical properties work synergistically to effectively impede sand particle flow, forming a durable sand-fixing network, making them suitable for sand-fixing material applications in desertification control projects.

[0098] The bamboo sheet 100 consists of a bamboo green layer, a bamboo flesh layer, and a bamboo yellow layer, arranged sequentially from the outer ring to the inner ring. The density of the bamboo flesh layer varies gradually from near the bamboo green layer to near the bamboo yellow layer, with a density of 0.85~1.0 g / cm³ near the bamboo green layer and 0.45~0.65 g / cm³ near the bamboo yellow layer. This density gradient characteristic allows the high-density area of ​​the outer ring of the bamboo sheet 100 to preferentially bear compressive stress under load, while the low-density area of ​​the inner ring absorbs energy through elastic deformation, forming a synergistic impact resistance mechanism similar to a "rigid-flexible composite layer." Compared with homogeneous materials, this can increase the bending fatigue life by approximately 50%.

[0099] Example 13:

[0100] The fan-shaped bamboo sheet 100 has a width of 12mm and a thickness of 2mm. The gap between adjacent bamboo sheets 100 is 6mm. The outer arc surface 101 and / or the inner arc surface 102 face the extension direction of the braided thread 200. The outer arc surface 101 and / or the inner arc surface 102 of adjacent bamboo sheets 100 face opposite directions. The outer arc surface 101 faces outward, and the inner arc surface 102 faces each other, forming a "trumpet shape". Figure 5 As shown. Specifically, the width at the entrance is 6mm, and the width at the exit is 5.83mm. All bamboo sheets 100 are perpendicular to the ground. The length of the bamboo sheet 100 inserted into the sand layer is 1 / 2 of its length, and the length of the bamboo sheet 100 protruding from the sand layer is 1 / 2 of its length. The thickness direction is lateral, and the side plane 103 is the windward side. A wind tunnel test was conducted with an ambient wind speed of 10 m / s.

[0101] Comparative Example 5:

[0102] The rectangular bamboo strips are 12mm wide and 2mm thick, with right angles at the edges; the gap between adjacent rectangular bamboo strips is 6mm. The width direction of the rectangular bamboo strips is the windward side. The length of the bamboo strip 100 inserted into the sand layer is 1 / 2 of its length, and the length of the bamboo strip 100 protruding from the sand layer is also 1 / 2 of its length. A wind tunnel test was conducted with an ambient wind speed of 10 m / s.

[0103] The properties of fan-shaped and rectangular bamboo strips are shown in Table 5:

[0104] Table 5

[0105]

[0106] The data shows that the fan-shaped bamboo sand barrier in Example 13 achieves significant technical advantages through the following innovative design: the windward side forms a "trumpet-shaped" gap layout, optimizing airflow distribution and reducing flow velocity and turbulence intensity; it reduces rebound, enhances deposition, and forms a dynamically balanced sand-fixing system; the structure has high durability, adapting to long-term wind and sand environments and reducing maintenance costs. Compared to rectangular bamboo strips, this design achieves breakthroughs in sand-fixing efficiency, environmental adaptability, and economy, providing a more efficient and sustainable solution for desertification control.

[0107] The second type of bamboo sheet 100 structure: The bamboo sheet 100 is prepared by cutting bamboo tubes along the tangential direction, such as... Figure 6 and Figure 7As shown; the cross-section of the bamboo sheet 100 is an isosceles trapezoid; the side surface of the bamboo sheet 100 consists of an outer section 104, an inner section 105, and a side plane 103 between the outer section 104 and the inner section 105; the outer arc surface 101 and / or the inner arc surface 102 face the extension direction of the braided thread 200; in the cross-section of the bamboo sheet 100, the vertical distance between the outer section 104 and the inner section 105 is the thickness b, and the distance between the two endpoints of the outer section 104 is the width w; the width-to-thickness ratio of the bamboo sheet is (5:1)~(25:1). The mechanical properties of the bamboo sheet 100 obtained by tangential cutting are shown in Table 6 (the bamboo sheets 100 prepared by tangential cutting from the outer layer to the inner layer correspond to P1 to P8):

[0108] Table 6

[0109]

[0110] The data shows that the bamboo sheet 100, prepared by tangential cutting along the bamboo tube, exhibits a unique gradient distribution of mechanical properties along its wall thickness (from the outer green layer to the inner yellow layer). Specifically, along the radial cross-section of the bamboo, the vascular bundle density and fiber volume fraction decrease from the outer green layer to the inner yellow layer, resulting in a continuous gradient decrease in mechanical properties such as tensile strength and elastic modulus from the outermost layer (outer green layer) to the innermost layer (inner yellow layer). In use, the bamboo sheet 100 closest to the outermost layer can be used.

[0111] Next, the technical effectiveness of the geometric parameters of the bamboo grid will be demonstrated through experimental results:

[0112] First, wind tunnel tests were conducted to study the effect of the side length of the bamboo grid on sand blocking. All bamboo sheets 100 had the same orientation for their outer arc surface 101 and / or inner arc surface 102; the width w was 10±2 mm, and the thickness b was 2 mm. The length of the bamboo sheet 100 was controlled at 300 mm, the depth of burial in the sand layer was controlled at 50% of its length, the gap width between the bamboo sheets 100 was 10 mm, the sand particle size was between 63 and 500 μm (normally distributed), and the wind speed was 15 m / s. The side length of the bamboo grid varied from 300 mm to 2500 mm to study its wind resistance, air permeability, and sand blocking performance. The performance is shown in Table 7.

[0113] Table 7

[0114]

[0115] The data shows that: when the side length of the bamboo grid increases from 300 mm to 2500 mm, wind resistance decreases significantly with increasing side length, while deflection increases synchronously; the safety factor increases linearly, indicating that larger-sized structures have better structural stability; wear depth decreases with increasing side length, which is related to a decrease in the number of impacts per unit area; air permeability increases positively, indicating that larger grids allow more airflow to pass through; the wind speed reduction effect decreases, which is directly related to the increase in air permeability; turbulent settling efficiency decreases, reflecting the weakening of turbulent disturbance in larger grids; the total interception rate decreases sharply with increasing side length, indicating that smaller-sized grids have a significant interception advantage; the direct interception dominance effect is stronger than turbulent settling, but both weaken with grid expansion, and the sand mass flux reduction rate decreases synchronously; ecological benefits improve with increasing size, indicating that larger grids are more conducive to ecosystem balance; burial time is significantly extended, indicating that larger grid structures are more durable; the impact force of a single sand grain increases, but the total number of impacts decreases by an order of magnitude. Medium-sized (500-1000mm) structures strike a balance between sand-blocking efficiency (75-65%) and ecological benefits (medium to excellent).

[0116] Second, wind tunnel tests were conducted to study the effect of the variation in the gap width of the bamboo slabs 100 in the bamboo grid. All bamboo slabs 100 had the same orientation for their outer arc surface 101 and / or inner arc surface 102; the width w was 10±2 mm, the thickness b was 2 mm, the length of the bamboo slabs 100 was controlled at 300 mm, the depth of the bamboo slabs 100 buried in the sand layer was 50% of their length, the size of the bamboo grid was 1000 mm, the sand particle size was between 63 and 500 μm (normally distributed), and the wind speed was 15 m / s. The gap width of the bamboo slabs 100 varied from 2 mm to 22 mm. The wind resistance, air permeability, and sand-blocking properties of the bamboo grid were studied, and the performance is shown in Table 8.

[0117] Table 8

[0118]

[0119] The data shows that wind resistance decreases linearly with increasing gap width, while air permeability increases significantly. This is because a larger gap width allows more airflow, reducing structural resistance, but weakens wind speed attenuation. The reduction in sand mass flux decreased from 75% to 45%, indicating that smaller gap widths (≤8mm) have better sand-blocking capabilities. The wind speed reduction effect decreased from 55% to 25%, negatively correlated with the increase in gap width. The impact force of a single sand grain increases with increasing gap width, but the number of impacts per unit area per year decreases, resulting in a decrease in wear depth overall.

[0120] Bamboo grids can achieve a functional gradient design, ranging from "high-strength protection" to "eco-friendly," by adjusting the gap width. A gap width of 2-8mm is suitable for rapid sand fixation in areas with abundant sand sources, a gap width of 12-16mm is suitable for comprehensive protection in ecological restoration areas, and a gap width of 20-22mm is recommended for vegetation conservation in already stabilized sandy areas. Dynamic optimization is required, taking into account wind speed, sand source intensity, and ecological objectives.

[0121] Third, wind tunnel tests were conducted to study the effect of the burial depth of bamboo slabs 100 in the bamboo grid. All bamboo slabs 100 had the same orientation for their outer arc surface 101 and / or inner arc surface 102. The width w was controlled at 10 ± 2 mm, the thickness b at 2 mm, the length of the bamboo slabs 100 at 300 mm, the gap width between the bamboo slabs 100 at 10 mm, the side length of the bamboo grid at 1000 mm, and the sand particle size at a normal distribution between 63 and 500 μm. The wind speed was 15 m / s. The burial depth varied from 10% to 70% of the length to study the wind resistance, air permeability, and sand-blocking properties of the bamboo grid. The performance is shown in Table 9.

[0122] Table 9

[0123]

[0124] The data shows a positive correlation between burial depth and wind resistance. As the depth increases from 10% to 70%, wind resistance increases from 0.015N to 0.120N, indicating a significant enhancement in the structure's wind resistance. Deflection decreases from 15mm to 1.2mm, and the safety factor increases from 15 to 140, demonstrating that increased burial depth significantly improves the structure's resistance to deformation. The wind speed reduction effect increases linearly from 15% to 60%. The sand mass flux reduction rate increases from 30% to 80%, indicating that a burial depth of 70% provides the best wind protection. The sand burial time is shortened from 15 months to 2 months, reflecting a positive correlation between structural interception efficiency and sand deposition rate. In summary, a burial depth of 40%–50% is the optimal economic range, achieving a total interception rate of 35% while maintaining optimal ecological benefits; the wear depth is 0.8–1.2mm / year, indicating a reasonable maintenance cycle.

[0125] Fourth, wind tunnel tests were conducted to study the effect of changes in the length of the bamboo slabs 100 in the bamboo grid. All bamboo slabs 100 had the same orientation for their outer arc surface 101 and / or inner arc surface 102. The width w was controlled at 10 ± 2 mm, the thickness b at 2 mm, the length of the bamboo slabs 100 at 300 mm, the gap width between the bamboo slabs 100 at 10 mm, the side length of the bamboo grid at 1000 mm, the burial depth at 50% of the length, the sand particle size at a normal distribution between 63 and 500 μm, and the wind speed at 15 m / s. The burial depth varied from 10% to 70% of the length to study the wind resistance, air permeability, and sand-blocking properties of the bamboo grid. The performance is shown in Table 10.

[0126] Table 10

[0127]

[0128] The data shows that wind resistance increases exponentially with length. When the length increases from 200mm to 800mm, the wind resistance increases from 0.040N to 0.350N (+775%). Longer, thinner sheets (≥600mm) experience a significant increase in wind load due to the increased windward area, but their wind resistance weakens (safety factor decreases from 220 to 12, -94.5%). Deflection increases sharply with length: only 0.5mm at 200mm, reaching 40mm at 800mm (+7900%), indicating insufficient bending stiffness and susceptibility to large deformation failure. The total interception rate peaks at 45% at 400mm (25% direct interception + 20% turbulent settling), and decreases with further length increases (only 22% at 800mm). The impact force of a single sand grain increased from 0.007 N (200 mm) to 0.018 N (800 mm) (+157%), and the number of impacts per unit area per year increased from 3.0 × 10¹ 0 The frequency of sand deposition increased from 1.1 × 10¹¹ times / m² to 1.1 × 10¹¹ times / m² (+267%), leading to an increase in wear depth from 0.6 mm / year to 2.7 mm / year (+350%). Sand burial time decreased from 12 months (200 mm) to 1.5 months (800 mm), reflecting that longer, thinner plates accelerate sand deposition but require more frequent maintenance. The optimal interception zone is 400–500 mm in length, with a total interception rate of 35%–45%, matching a permeability of 50%–45% to form a highly efficient wind-sand separation zone. The wind speed reduction effect increased linearly from 18% (200 mm) to 65% (800 mm), but the sand flux reduction rate decreased after reaching 70% at 400 mm (55% at 800 mm), indicating that while excessively long plates reduce wind speed, they exacerbate sand escape.

[0129] To improve the UV resistance of the bamboo sheet 100, the surface of the bamboo sheet 100 is coated with a UV-resistant coating; the UV-resistant coating contains titanium dioxide, benzotriazole UV absorbers and silica-alumina sol, and the coating thickness is 50~100nm.

[0130] This utility model provides a method for preparing a bamboo sand barrier, comprising the following steps:

[0131] S1. Cut the original bamboo into bamboo tubes with a length of 150~500cm, and then split the bamboo tubes radially into several fan-shaped bamboo strips with equal arc length.

[0132] S2. Split the fan-shaped bamboo strips radially and feed them into the first bamboo splitting machine. The first splitting machine consists of one bamboo splitting machine. It splits the arc-shaped bamboo strips radially into two bamboo strips of the same width. The two bamboo strips are fed into the second bamboo splitting machine. The second bamboo splitting machine consists of two bamboo splitting machines. It splits the two bamboo strips into four bamboo strips of the same width. The four bamboo strips are fed into the third bamboo splitting machine. The third bamboo splitting machine consists of four bamboo splitting machines. It splits the four bamboo strips into eight bamboo strips. The eight bamboo strips are fed into the fourth bamboo splitting machine. The fourth splitting machine consists of eight bamboo splitting machines. It splits the eight bamboo strips into 16 pieces. And so on, until the bamboo strips are split into fan-shaped bamboo strips with a width-to-thickness ratio of (5:1) to (25:1).

[0133] S3. Dry the bamboo slices to a moisture content of 8-30%;

[0134] S4. The bamboo sheets are arranged in parallel. A weaving machine is used to form a warp and weft interwoven mesh structure with the weaving threads and bamboo sheets. The bamboo sheets are woven into one piece by inserting or knotting.

[0135] The steps following S3 and before S4 include:

[0136] S5. Benzotriazole UV absorber, titanium dioxide, silica-alumina sol and matrix resin are compounded in a ratio of 3:0.8:5.0:100 to form a uniform UV-resistant coating. The silica-alumina sol has a solid content of 20-30% and a pH value of 8-10. The titanium dioxide is rutile with a particle size of 20-50 nm. The matrix resin is acrylic resin or polyurethane resin.

[0137] The specific preparation process of UV-protective coating is as follows:

[0138] S51. Add titanium dioxide to the silica-alumina sol and ultrasonically disperse for 45 minutes;

[0139] S52. Add the benzotriazole ultraviolet absorber to the matrix resin and stir until completely dissolved;

[0140] S53. Slowly add the titanium dioxide-silica aluminum sol dispersion obtained in S51 to the resin mixture in S52, and stir at high speed for 1.5 hours.

[0141] S54, let stand for 24 hours to mature, and then filter to obtain UV-resistant coating;

[0142] S6. Immerse the bamboo sheet in the UV-resistant coating, controlling the immersion amount to 3-5‰, to obtain the bamboo sheet coated with the UV-resistant coating.

[0143] Finally, it should be noted that the above-described embodiments are merely specific implementations of this utility model, used to illustrate the technical solutions of this utility model, and not to limit it. The protection scope of this utility model is not limited thereto. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the technical scope disclosed in this utility model. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model, and should all be covered within the protection scope of this utility model.

Claims

1. A bamboo grid, characterized in that, The bamboo grid is formed by connecting two L-shaped or four straight bamboo barriers end to end to form a square-shaped bamboo grid; the side length of the bamboo grid is 500~1000mm; The bamboo sand barrier is a mesh structure composed of woven threads and thin bamboo sheets, with the bamboo sheets arranged in parallel along the longitudinal direction; the woven threads extend perpendicularly to the bamboo sheets, and there is at least one woven thread on each bamboo sheet. The length of the bamboo slabs is 200~600mm; The length-to-thickness ratio of bamboo slabs is (100:1)~(500:1); There are gaps between adjacent bamboo slabs, and the width of the gaps is 0.2 to 2.2 times the width of the bamboo slabs.

2. The bamboo grid according to claim 1, characterized in that, The embedding length of the bamboo slabs in the bamboo grid is 40-50% of the length of the bamboo slabs.

3. The bamboo grid according to claim 1, characterized in that, Bamboo sheets are prepared by radially slicing bamboo tubes; the cross-section of the bamboo sheet is fan-shaped; the side surface of the bamboo sheet consists of an outer arc surface, an inner arc surface, and a side plane between the outer arc surface and the inner arc surface; the outer arc surface and / or the inner arc surface face the direction of extension of the braided thread; In the cross-section of the bamboo sheet, the distance between the two farthest endpoints of the outer arc surface is the thickness b, and the distance between the endpoint where the side plane meets the outer arc surface and the endpoint where the side plane meets the inner arc surface is the width w. The width-to-thickness ratio of bamboo slabs is (5:1) to (25:1).

4. The bamboo grid according to claim 3, characterized in that, The thickness of bamboo slabs is 0.8~4.0mm.

5. The bamboo grid according to claim 3, characterized in that, In the bamboo sand barrier, the outer and / or inner curved surfaces of all bamboo sheets face the same direction.

6. The bamboo grid according to claim 3, characterized in that, In a bamboo sand barrier, the outer and / or inner curved surfaces of adjacent bamboo sheets face opposite directions.

7. The bamboo grid according to claim 1, characterized in that, Bamboo sheets are prepared by cutting bamboo tubes along the tangential direction. The sides of the bamboo sheet are an outer cut surface, an inner cut surface, and a side plane between the outer cut surface and the inner cut surface; the outer arc surface and / or the inner arc surface face the direction of extension of the braided thread; In the cross-section of a bamboo sheet, the vertical distance between the outer and inner cutting surfaces is the thickness b, and the distance between the two ends of the outer cutting surface is the width w. The width-to-thickness ratio of bamboo slabs is (5:1) to (25:1).

8. The bamboo grid according to claim 1, characterized in that, The braided thread is one of hemp rope or cotton rope. When there are two braided threads, the gap between adjacent braided threads in the horizontal direction is 10~30cm.

9. The bamboo grid according to claim 1, characterized in that, The surface of the bamboo slab is coated with a UV-resistant coating; the coating thickness is 50~100nm.

10. The bamboo grid according to claim 1, characterized in that, The length of the bamboo slabs is 300~500mm.

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