The joints and manufacturing method of the round bamboo structure using plastic cup sleeves and PVC linings

Abstract

This invention discloses a bamboo structure splicing joint using a plastic cup sleeve and a PVC liner, and its manufacturing method. The splicing joint includes: two round bamboo culms, the splicing ends of which define two round bamboo tubes, each tube containing an internal cavity; a plastic cup sleeve, the inner and outer surfaces of which are uniformly coated with resin as a structural adhesive and placed within the internal cavity of the two bamboo tubes, the cup sleeve also containing an internal cavity; a PVC liner tube, which contains an internal cavity within the plastic cup sleeve; and metal connectors, which can be screws or bolts, arranged crosswise and penetrating the PVC liner tube, the plastic cup sleeve, and the bamboo tubes. The bamboo tube splicing joint using a plastic cup sleeve and a PVC liner effectively inhibits crack propagation in the bamboo during stress, while significantly improving the load-bearing capacity, bending resistance, and torsional resistance of the bamboo tubes, making the structure more stable under stress.

Description

Technical Field

[0001] This invention relates to the field of civil engineering, and in particular to a novel round bamboo splicing joint and its manufacturing method. Background Technology

[0002] With the advent of green building and sustainable development concepts, round bamboo, as a renewable, low-carbon, and environmentally friendly building material, is increasingly being used in the construction field. Round bamboo possesses excellent mechanical properties and rapid growth characteristics, making it an ideal alternative building material. However, in structural applications, round bamboo joints are prone to uneven stress distribution and cracking, especially the relatively weak compressive, tensile, and torsional resistance of splice joints. Existing round bamboo structural joint designs mostly employ traditional bolt connections, which easily lead to localized stress concentration, reducing the durability and stability of the joints.

[0003] This invention aims to address the shortcomings of bamboo structure splicing joints in terms of compressive, tensile, and torsional resistance, and proposes a novel splicing joint design that improves the overall mechanical performance of the joint by using a multi-material composite approach. Summary of the Invention

[0004] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a bamboo tube splicing joint using a plastic cup sleeve and a PVC lining. This splicing joint can effectively inhibit the expansion of cracks in the bamboo material during the stress process, while significantly improving the load-bearing capacity, bending resistance, and torsional resistance of the bamboo tube, making the structure more stable under stress.

[0005] According to an embodiment of the present invention, a circular bamboo structure splicing node using a plastic cup sleeve and a PVC liner includes: two circular bamboo stalks, the splicing ends of the two circular bamboo stalks defining two circular bamboo tubes, the interior of each circular bamboo tube defining an internal cavity; a plastic cup sleeve, the inner and outer surfaces of which are uniformly coated with resin as a structural adhesive, specifically, the resin includes at least one of epoxy resin, polyurethane resin, and bio-based resin, the plastic cup sleeve being disposed within the internal cavity of the two circular bamboo tubes, the interior of which defines the internal cavity; a PVC liner tube, the interior of which defines the internal cavity, the PVC liner tube being disposed within the plastic cup sleeve defining the internal cavity; and metal connectors, the metal connectors being screws or bolts, arranged crosswise and penetrating the PVC liner tube, the plastic cup sleeve, and the circular bamboo tubes.

[0006] According to embodiments of the present invention, a multi-layered design employing a plastic cup sleeve to bond the PVC inner liner tube and the round bamboo tube, along with cross-laid metal connectors, effectively suppresses further cracking of the bamboo tube under stress, improves the overall mechanical properties of the bamboo tube, significantly enhances its load-bearing capacity and deformation capacity, and makes its stress performance more stable. Simultaneously, the lightweight plastic cup sleeve, nestled between the PVC pipe and the bamboo, reduces its own weight, provides internal support, and buffers stress transmission, avoiding localized stress concentration. The PVC inner liner provides basic internal support, especially at joint connections, helping to improve the rigidity of the joint. The metal connectors can transmit the shear force on the round bamboo tube while fixing the position of the plastic cup sleeve and the PVC inner liner tube, preventing movement. Spring washers are provided between the bolts and the bamboo tube to provide additional cushioning and tightening effects, preventing damage to the bamboo during bolt tightening and ensuring the long-term stability of the joint connection.

[0007] In some embodiments of the present invention, the larger outer diameter of the two round bamboo tubes at the joint of the round bamboo culms is D, the smaller inner diameter is D1, and the smaller length of the internal cavity is L. The plastic cup sleeve is similar in structure to a drinking cup, with one end closed (closed end) and the other end open (open end). The outer diameter of the open end is D1, and the inner diameter is 4mm smaller than D1 (i.e., D1-4mm); the outer diameter of the closed end is D1-1mm, and the bottom of the closed end inside the cup sleeve forms a circular cross-section with a diameter of D1-5mm. The plastic cup sleeve is disposed in the internal cavity of the two round bamboo tubes, and the length of the plastic cup sleeve is l, not exceeding L. The open end is flush with the end face of the bamboo tube and is not exposed, while the closed end is inserted into the internal cavity of the bamboo tube. The outer diameter of the PVC inner tube is not greater than D1-5mm and is disposed inside the two plastic cup sleeves. The length of the PVC inner tube is 2l, which is exactly divided equally by the two plastic cup sleeves.

[0008] In some embodiments of the present invention, the outer diameter of the two round bamboo tubes at the splicing point of the round bamboo culms is larger than D, and the diameter of the metal connector is d and the length is greater than D, and they are arranged symmetrically between the two round bamboo tubes.

[0009] In some embodiments of the present invention, the metal connectors are bolts, which are arranged in a cross-shaped symmetrical manner at a distance of not less than 6d from the end of the bamboo tube, and the distance between adjacent metal connectors is not less than 5d.

[0010] In some embodiments of the present invention, the metal connectors are screws, which are located at a distance of not less than 8d from the end of the bamboo tube. The number of screws is 2n, and they are arranged alternately along the circumferential direction of the two round bamboo walls. They are evenly and symmetrically arranged around the circumference at 360 / n° intervals in the circumferential direction of the bamboo wall, and the distance between adjacent metal connectors is not less than 4d.

[0011] A method for manufacturing a round bamboo structure splicing node using a plastic cup sleeve and a PVC lining according to some embodiments of the present invention includes the following steps:

[0012] S10. The two round bamboo stalks are placed horizontally in a relative manner, so that the internal cavities defined by the two round bamboo tubes at the joint of the round bamboo stalks are opposite and aligned, so as to be spliced.

[0013] S20. Apply resin adhesive evenly to the outer surface of the plastic cup sleeve. First, insert the closed end of the plastic cup sleeve into the inner cavity of the bamboo tube, and push it in along the insertion direction. When the open end of the plastic cup sleeve is flush with the end face of the bamboo tube, stop inserting; at this point, the open end should not be exposed. Let it stand and wait for the adhesive to cure, forming a reinforced area that is completely covered.

[0014] S30. Apply adhesive evenly to the inside of the two plastic cup sleeves, and insert the PVC inner lining tube into the inner cavity of the first plastic cup sleeve until the PVC inner lining tube touches the bottom surface of the cup sleeve. Then, continue inserting the PVC inner lining tube into the second plastic cup sleeve. When the two round bamboo tubes fit together almost seamlessly, the installation is complete.

[0015] S40. Mark the drilling positions on the two round bamboo tubes. According to the marked drilling positions, drill holes in one of the round bamboo tubes in sequence. When drilling, the holes should pass through the round bamboo tube, the plastic cup sleeve, and the inner PVC lining tube. After passing through the round bamboo tube, fix it according to the type of metal connector.

[0016] S41. The metal connector is a bolt. After drilling, the bolt is placed into the hole, and spring washers are placed in sequence and fixed with nuts. After each metal connector is installed, the next hole is drilled and installed until all the metal connectors of the bamboo tube are installed.

[0017] S42. The metal connector is a screw. After drilling, the screw is directly screwed in to fix it. After each metal connector is installed, the next hole is drilled and installed, until all the metal connectors of the bamboo tube are installed.

[0018] Additional advantages and features of the invention will be set forth in part in the description which follows, and in part will be obvious from the description or will be understood by practice of the invention. Attached Figure Description

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0020] Figure 1This is a schematic diagram of the manufacturing method of the splicing node of the round bamboo structure using plastic cup sleeve and PVC lining according to Embodiment 1 of the present invention. It shows the splicing node connected by 6 bolts. The bolts are arranged symmetrically in a cross shape on the outside of the round bamboo tube. The bolt end distance is 6d and the spacing is 5d.

[0021] Figure 2 This is a schematic diagram of a circular bamboo structure splicing node using a plastic cup sleeve and a PVC liner according to Embodiment 1 of the present invention. It shows a splicing node connected by 8 screws. The screws are arranged in an alternating manner along the circumferential direction of the two circular bamboo walls. They are evenly and symmetrically arranged around the circumference at 360 / 4° intervals in the circumferential direction of the bamboo walls. The screw ends are 8d apart and the spacing is 4d.

[0022] Figure 3 This is a flowchart of the manufacturing method for splicing nodes of a round bamboo structure using a plastic cup sleeve and a PVC lining.

[0023] Reference numerals

[0024] FRP-reinforced and PVC-lined round bamboo structure splicing node 100;

[0025] 1. Round bamboo tube;

[0026] 2 plastic cup sleeves;

[0027] PVC inner lining pipe 3;

[0028] 4 metal connectors (bolts / screws); 41 spring washers; 42 nuts. Detailed Implementation

[0029] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0030] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0031] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0032] Reference below Figure 1 This invention describes an embodiment of a round bamboo structure splicing node 100 with FRP reinforcement and PVC lining according to the present invention. The embodiment includes: two round bamboo tubes 1, two plastic cup sleeves 2, a PVC lining tube 3, metal connectors (bolts / screws) 4, spring washers 41, and nuts 42.

[0033] like Figure 1 As shown, a round bamboo tube 1 defines an internal cavity, and two plastic cup sleeves 2 are disposed within the internal cavities of the two round bamboo tubes 1. The two plastic cup sleeves 2 define two internal cavities, and a PVC inner lining tube 3 is disposed within the cavity defined by the plastic cup sleeves 2. The plastic cup sleeves 2 are lightweight and are nested between the PVC inner lining tube 3 and the bamboo material to reduce their own weight, provide internal support, and buffer stress transmission, avoiding localized stress concentration. The PVC inner lining tube 3 provides basic internal support, especially at joint connections, helping to improve the rigidity of the joint.

[0034] like Figure 1As shown, the metal connector 4 includes screws or bolts, which are arranged in a crisscross pattern, penetrating the PVC inner liner tube 3, the plastic cup sleeve 2, and the round bamboo tube 1. The crisscross arrangement of the metal connectors allows them to be fixed to the round bamboo tube 1, transmitting the force on the bamboo tube 1 and acting similarly to a bamboo joint. It also fixes the positions of the plastic cup sleeve 2 and the PVC inner liner tube 3, preventing movement. A spring washer 41 is provided between the bolt and the bamboo tube 1 to provide additional cushioning and tightening, preventing damage to the bamboo during tightening and ensuring the long-term stability of the joint connection.

[0035] like Figure 1 As shown, the larger outer diameter of the two round bamboo tubes 1 at the joint of the round bamboo stalks is D, the smaller inner diameter is D1, and the smaller length of the internal cavity is L. The plastic cup sleeve 2 is similar in structure to a drinking cup, with one end closed (closed end) and the other end open (open end). The outer diameter of the open end is D1, and the inner diameter is 4mm smaller than D1 (i.e., D1-4mm); the outer diameter of the closed end is D1-1mm. The bottom of the closed end inside the cup sleeve 2 forms a circular cross-section with a diameter of D1-5mm. The plastic cup sleeve 2 is placed inside the internal cavity of the two round bamboo tubes 1, and the length of the plastic cup sleeve 2 is l, not exceeding L. The open end is flush with the end face of the bamboo tube 1 and is not exposed, while the closed end is inserted into the internal cavity of the bamboo tube 1. The outer diameter of the PVC inner lining tube 3 is no greater than D1-5mm, and it is placed inside the two plastic cup sleeves 2. The length of the PVC inner lining tube 3 is 2l, which is exactly divided equally by the two plastic cup sleeves 2.

[0036] like Figure 1 As shown, the inner and outer surfaces of the plastic cup sleeve 2 are uniformly coated with resin as a structural adhesive. Specifically, the resin includes at least one of epoxy resin, polyurethane resin and bio-based resin.

[0037] like Figure 1 As shown, the outer diameter of the two round bamboo tubes 1 at the splicing point of the round bamboo culms is larger than D, and the diameter of the metal connector 4 is d and the length is greater than D. They are arranged symmetrically between the two round bamboo tubes 1.

[0038] like Figure 1 As shown, the metal connector 4 is made of bolts, and is arranged in a cross-shaped symmetrical manner at a distance of not less than 6d from the end of the bamboo tube 1, and the distance between adjacent metal connectors 4 is not less than 5d.

[0039] The following is based on Figure 1 The image illustrates a method for manufacturing a circular bamboo structure splicing node 100 using a plastic cup sleeve 2 and a PVC inner lining tube 3, according to an embodiment of the present invention. The manufacturing method includes the following steps:

[0040] S10. Two round bamboo stalks 1 are placed horizontally in a relative manner, so that the internal cavities defined by the two round bamboo tubes 1 at the joint of the round bamboo stalks 1 are opposite and aligned, so as to be spliced.

[0041] S20. Apply resin adhesive evenly to the outer surface of the plastic cup sleeve 2. First, insert its closed end into the inner cavity of the bamboo tube 1, and push it in along the insertion direction. When the open end of the plastic cup sleeve 2 is flush with the end face of the bamboo tube 1, stop inserting. At this time, the open end should not be exposed. Let it stand and wait for the adhesive to cure, forming a reinforced area that is completely covered.

[0042] S30. Apply adhesive evenly to the inside of the two plastic cup sleeves 2, and insert the PVC inner lining tube 3 into the inner cavity of the first plastic cup sleeve 2 until the PVC inner lining tube 3 touches the bottom surface of the plastic cup sleeve 2. Then, continue to insert the PVC inner lining tube 3 into the second plastic cup sleeve 2. When the two round bamboo tubes 1 fit together almost seamlessly, the installation is complete.

[0043] S40. Mark the drilling positions on the two round bamboo tubes 1. According to the marked drilling positions, drill holes in one of the round bamboo tubes 1 in sequence. When drilling, the holes should pass through the round bamboo tube 1, the plastic cup sleeve 2, and the inner PVC lining tube 3. After passing through the round bamboo tube 1, fix it according to the type of metal connector 4.

[0044] S41. Metal connector 4 is a bolt. After drilling, the bolt is inserted into the hole, and spring washers 41 are inserted in sequence and secured with nuts 42. After each metal connector 4 is installed, the next hole is drilled and installed until all metal connectors 4 of the round bamboo tube 1 are installed.

[0045] S42. The metal connector 4 is a screw. After drilling, the screw is directly screwed in to fix it. After each metal connector 4 is installed, the next hole is drilled and installed, until all the metal connectors 4 of the round bamboo tube 1 are installed.

[0046] Figure 1 A method for manufacturing a round bamboo structure splicing node 100 with FRP reinforcement and PVC lining is demonstrated. By adjusting and changing the number and position of the metal connectors 5, a variety of connection methods can be formed to meet the construction requirements in different scenarios. This reduces engineering costs and improves the overall stability and safety of the structure while ensuring ease of construction.

[0047] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0048] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A circular bamboo structure splicing joint using a plastic cup sleeve and a PVC lining, characterized in that, include: Two round bamboo stalks, the splicing ends of the two round bamboo stalks define two round bamboo tubes, and the inside of the round bamboo tubes defines an internal cavity; A plastic cup sleeve, wherein the plastic cup sleeve is disposed in the internal cavity of the two round bamboo tubes, and the internal cavity is defined by the inside of the plastic cup sleeve; A PVC inner liner tube, the inner cavity of which is defined, is disposed inside the plastic cup sleeve; metal connectors, the metal connectors being screws or bolts, are arranged in a cross pattern and pass through the PVC inner liner tube, the plastic cup sleeve, and the round bamboo tube. The larger outer diameter of the two round bamboo tubes at the joint of the round bamboo culms is D, the smaller inner diameter is D1, and the smaller length of the internal cavity is L. The plastic cup sleeve is similar to the structure of a drinking cup, with one end closed and the other end open. The plastic cup sleeve is set in the internal cavity of the two round bamboo tubes, and the length of the plastic cup sleeve is l, not exceeding L. The open end is flush with the end face of the bamboo tube and is not exposed, while the closed end is inserted into the internal cavity of the bamboo tube. The PVC inner lining tube is set inside the two plastic cup sleeves. The length of the PVC inner lining tube is 2l, which is exactly divided equally by the two plastic cup sleeves. The inner and outer surfaces of the plastic cup sleeve are uniformly coated with resin as a structural adhesive. Specifically, the resin includes at least one of epoxy resin, polyurethane resin and bio-based resin. The metal connectors are arranged symmetrically and crosswise between the two round bamboo tubes; The PVC inner lining tube provides basic internal support and helps improve the rigidity of the joint at the connection point. The metal connectors transmit the shear force on the round bamboo tube and fix the position of the plastic cup sleeve and the PVC inner lining tube.

2. The round bamboo structure splicing node of the plastic cup sleeve and PVC lining according to claim 1, characterized in that, The outer diameter of the open end is D1, and the inner diameter is 4mm smaller than D1; the outer diameter of the closed end is D1-1mm, and the bottom of the closed end inside the cup sleeve forms a circular cross section with a diameter of D1-5mm; the outer diameter of the PVC inner lining tube is not greater than D1-5mm.

3. The round bamboo structure splicing node of the plastic cup sleeve and PVC lining according to claim 1, characterized in that, The outer diameter of the two round bamboo tubes at the splicing point of the round bamboo culms is larger than D, and the diameter of the metal connector is d and its length is greater than D.

4. The round bamboo structure splicing node of the plastic cup sleeve and PVC lining according to claim 3, characterized in that, The metal connectors are bolts, and are arranged in a cross-shaped symmetrical pattern at a distance of not less than 6d from the end of the bamboo tube, with an adjacent metal connector at a distance of not less than 5d.

5. The round bamboo structure splicing node of the plastic cup sleeve and PVC lining according to claim 3, characterized in that, The metal connectors are screws, which are located at a distance of not less than 8d from the end of the bamboo tube. The number of screws is 2n. They are arranged alternately along the circumferential direction of the two round bamboo tubes, and are evenly and symmetrically arranged around the circumference at 360 / n° intervals. The distance between adjacent metal connectors is not less than 4d.

6. A method for manufacturing a round bamboo structure splicing node using a plastic cup sleeve and a PVC lining, characterized in that, According to any one of claims 1 to 5, the manufacturing method of the round bamboo structure splicing node using a plastic cup sleeve and a PVC liner includes the following steps: S10, the two round bamboo stalks are placed horizontally in a relative manner, so that the internal cavities defined by the two round bamboo tubes at the splicing point of the round bamboo stalks are opposite and aligned for splicing; S20, resin glue is evenly applied to the outer surface of the plastic cup sleeve, and its closed end is first inserted into the internal cavity of the bamboo tube and pushed in along the insertion direction; when the open end of the plastic cup sleeve is flush with the end face of the bamboo tube, the insertion is stopped, at which point the open end is not exposed; the adhesive is left to cure, forming a reinforced area that is completely covered; S30, glue is evenly applied to the inside of the two plastic cup sleeves, and the PVC liner tube is inserted into the internal cavity of the first plastic cup sleeve until the PVC liner tube touches the bottom surface of the cup sleeve; thereafter, the PVC liner tube is... Continue inserting the second plastic cup sleeve. When the two round bamboo tubes fit together seamlessly, the installation is complete. S40: Mark the drilling positions on the two round bamboo tubes. According to the marked drilling positions, drill holes in one of the round bamboo tubes in sequence. When drilling, the holes should pass through the round bamboo tube, the plastic cup sleeve, and the inner PVC liner tube. After passing through the round bamboo tube, fix it according to the type of metal connector. S41: If the metal connector is a bolt, after drilling, put the bolt into the hole, and then insert spring washers in sequence and fix it with nuts. After completing the installation of each metal connector, drill and install the next hole until all metal connectors of the bamboo tube are installed. S42: If the metal connector is a screw, after drilling, screw the screw directly into the hole to fix it. After completing the installation of each metal connector, drill and install the next hole until all metal connectors of the bamboo tube are installed.

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