Engineering bamboo beam column connecting joint and manufacturing method

Abstract

The invention relates to an engineering bamboo beam column connecting joint and a manufacturing method, the engineering bamboo beam column connecting joint comprises an engineering bamboo column and an engineering bamboo beam connected with the engineering bamboo column, and the joint of the engineering bamboo column and the engineering bamboo beam is correspondingly provided with at least one inclined plane contact part and a straight plane contact part. An acute included angle is formed between the inclined plane of the inclined plane contact part and the fiber direction of the engineering bamboo beam; the engineering bamboo beam is spliced with the engineering bamboo column through the inclined surface contact part and the straight surface contact part; and the self-tapping screw is drilled in the direction inclined to the fiber direction of the engineering bamboo beam, penetrates through the engineering bamboo beam and is anchored in the engineering bamboo column, so that the initial rigidity of the joint in the plane is improved through mutual matching of the inclined plane contact part, the straight plane contact part and the self-tapping screw. According to the engineering bamboo beam column connecting joint and the manufacturing method, the load transmission path is ensured, and the initial rigidity of the joint is improved.

Description

Technical Field

[0001] This invention relates to the field of civil engineering technology, and in particular to an engineering bamboo beam-column connection node and its manufacturing method. Background Technology

[0002] After standardized processing, engineered bamboo overcomes the material defects and dimensional variability of round bamboo, exhibiting stable mechanical properties and gradually being applied to load-bearing engineering structures. Existing engineered bamboo structures largely borrow design concepts from heavy timber structures, employing bolted connections. However, the unavoidable initial gap between the bolt and the bolt hole causes slippage at the joint under load, significantly reducing initial stiffness. Insufficient initial stiffness directly affects the deformation control capability of the joint, weakening the overall structural stability and becoming a technical problem restricting the efficient load-bearing capacity and safe service of engineered bamboo structures. Summary of the Invention

[0003] Therefore, it is necessary to provide an engineering bamboo beam-column connection node and its manufacturing method to address the technical problem of low initial rigidity of the aforementioned engineering bamboo connection nodes.

[0004] The present invention provides an engineering bamboo beam-column connection node, comprising an engineering bamboo column and an engineering bamboo beam connected to the engineering bamboo column. The joint of the engineering bamboo column and the engineering bamboo beam is respectively provided with at least one inclined surface contact part and one straight surface contact part, and the inclined surface of the inclined surface contact part forms an acute angle with the fiber direction of the engineering bamboo beam. The engineering bamboo beams are spliced ​​to the engineering bamboo columns through the inclined contact portion and the straight contact portion; It also includes self-tapping screws, which are drilled in a direction inclined to the direction of the engineered bamboo beam fibers, penetrate the engineered bamboo beam and are anchored in the engineered bamboo column, so as to improve the initial in-plane stiffness of the node through the cooperation of the inclined contact part, the straight contact part and the self-tapping screw.

[0005] In one embodiment, the angle between the inclined surface of the inclined contact portion and the direction of the engineered bamboo fiber is 45 degrees.

[0006] In one embodiment, there are at least two inclined contact portions, which are symmetrically arranged on both sides of the joint between the engineering bamboo beam and the engineering bamboo column, and at least one straight contact portion, which is arranged between the inclined contact portions on both sides.

[0007] In one embodiment, the length of the inclined side of the inclined projection of the inclined surface of the inclined surface contact portion on the engineering bamboo beam is equal to the cross-sectional height of the engineering bamboo beam.

[0008] In one embodiment, the cross-sectional width of the inclined contact portion is less than or equal to one-quarter of the cross-sectional width of the engineering bamboo column.

[0009] In one embodiment, the length of the straight contact portion extending into the engineering bamboo column is one-third to two-thirds of the cross-sectional height of the engineering bamboo column.

[0010] In one embodiment, the length of the straight contact portion extending into the engineering bamboo column is half the cross-sectional height of the engineering bamboo column.

[0011] In one embodiment, the drilling direction of the self-tapping screw forms a 45-degree angle with the direction of the engineered bamboo fiber.

[0012] In one embodiment, the anchorage length of the self-tapping screw within the engineered bamboo column is not less than 100 mm.

[0013] This invention also provides a method for fabricating an engineering bamboo beam-column connection node, used to fabricate the engineering bamboo beam-column connection node as described above, comprising: The inclined contact portion and the straight contact portion are respectively processed on the engineering bamboo column and the engineering bamboo beam to fit each other; The processed engineering bamboo beams and engineering bamboo columns are spliced ​​together through inclined contact parts and straight contact parts; Drill the self-tapping screws into the engineered bamboo beam at an angle to the direction of the bamboo fiber, so that they penetrate the engineered bamboo beam and are anchored inside the engineered bamboo column.

[0014] The aforementioned bamboo beam-column connection node and fabrication method, by setting up inclined contact parts, allows for a larger surface contact area between the bamboo beams and columns during jointing. This increases the contact area and frictional resistance between the components, effectively preventing slippage caused by initial gaps in bolted connections during load transfer and improving the initial in-plane stiffness of the node. Simultaneously, the straight contact parts further provide bearing support, working in conjunction with the inclined contact parts; while the self-tapping screws, drilled and anchored at an angle, not only provide additional connection constraints but also, together with the inclined contact, enhance the overall integrity of the node, ensuring the load transfer path and achieving an improvement in the initial stiffness of the node. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the joint state of the bamboo beam-column connection node in an embodiment of an engineering project. Figure 2 for Figure 1 The left view; Figure 3 for Figure 1 Schematic diagram of bamboo pillars in the project; Figure 4 for Figure 3 The left view; Figure 5 for Figure 1 Schematic diagram of drilling self-tapping screws into bamboo beams in a Chinese engineering project; Figure 6 for Figure 5 Top view; Figure 7 This is a flowchart illustrating a method for fabricating a bamboo beam-column connection node in an engineering project, as shown in one embodiment.

[0017] Figure label: 110. Engineering bamboo column; 112. Angled contact groove; 114. Straight contact groove; 120. Engineering bamboo beam; 122. Angled contact part; 124. Straight contact part; 130. Self-tapping screw. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this specification are for illustrative purposes only and do not represent the only possible implementation.

[0020] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0021] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0022] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0023] The following is combined with Figures 1-7 This invention describes the engineering bamboo beam-column connection node and its manufacturing method.

[0024] like Figures 1 to 6 As shown, in one embodiment, an engineering bamboo beam-column connection node includes an engineering bamboo column 110 and an engineering bamboo beam 120 connected to the engineering bamboo column 110.

[0025] The joint between the engineered bamboo column 110 and the engineered bamboo beam 120 is provided with at least one inclined contact portion 122 and one straight contact portion 124 respectively. The inclined surface of the inclined contact portion 122 forms an acute angle with the fiber direction of the engineered bamboo beam 120, and the inclined contact portions 122 and straight contact portions 124 are spaced apart. Optionally, the inclined contact portion 122 has two inclined surfaces, which are perpendicular to each other and form a 45-degree angle with the fiber direction of the engineered bamboo beam 120. The straight contact portion 124 is a 90-degree tangent section, that is, the straight contact portion 124 is formed by 90 degrees tangent to the fiber direction of the engineered bamboo beam 120. The two inclined surfaces may not be perpendicular, that is, they can be set as obtuse angles or acute angles. Alternatively, only one inclined surface may be provided on each inclined contact portion. At least two inclined contact portions 122 are symmetrically arranged on both sides of the joint between the engineering bamboo beam 120 and the engineering bamboo column 110. At least one straight contact portion 110 is arranged between the two inclined contact portions 122 to achieve balanced load distribution. The inclined side length of the inclined projection of the inclined contact portion 122 onto the engineering bamboo beam 120 is equal to the cross-sectional height of the engineering bamboo beam 120, and the cross-sectional width is less than one-quarter of the cross-sectional width of the engineering bamboo column 110. The cross-sectional height of the straight contact portion 124 is the same as the cross-sectional height of the engineering bamboo beam 120, and the cross-sectional width is less than or equal to one-quarter of the cross-sectional width of the engineering bamboo column 110. The length of the straight contact portion 124 extending into the engineering bamboo column 110 is one-third to two-thirds of the cross-sectional height of the engineering bamboo column 110, preferably one-half, to ensure a tight fit between the contact surfaces. The inclined contact portions 122 are easy to process and concentrated on both sides, while the straight contact portions 124 are located in the middle or near the middle, together expanding the beam-column contact area. The inclined contact portion 122 increases the shear surface through a 45-degree inclined plane, improving load transfer efficiency. The straight contact portion 124 provides the main bearing support, synergistically enhancing the initial in-plane stiffness and bending bearing capacity of the node. At the same time, the contact surface design avoids the adverse effects of bolt gaps. The inclined contact portion 122 uses inclined friction and bearing pressure to disperse stress, while the straight contact portion 124 bears the axial load. The combination of the two significantly improves the stiffness and stability of the node. The node has a high degree of prefabrication and is easy to construct, effectively suppressing cross-grain splitting of bamboo and extending its service life.

[0026] The engineered bamboo beam 120 is spliced ​​with the engineered bamboo column 110 through the inclined contact portion 122 and the straight contact portion 124. First, the engineered bamboo column 110 and the engineered bamboo beam 120 are machined to form a 45-degree inclined section (inclined surface) on the engineered bamboo beam 120 as the inclined contact portion 122. The length of the hypotenuse of the right triangle formed by the orthographic projection of the inclined contact portion 122 on the engineered bamboo beam 120 is equal to the cross-sectional height of the engineered bamboo beam, and the cross-sectional width is less than or equal to one-quarter of the cross-sectional width of the engineered bamboo column 110. The inclined surface forms a 45-degree angle with the direction of the beam fiber. An inclined contact groove 112 corresponding to the shape of the inclined contact portion 122 is machined on the engineered bamboo column 110 to accommodate the inclined contact portion 122. Simultaneously, a 90-degree tangential section is formed on the engineering bamboo beam 120 as a straight-face contact part 124. The height of the section is the same as the height of the engineering bamboo beam 120, and the width of the section is less than or equal to one-quarter of the width of the engineering bamboo column section. The length of the section extending into the engineering bamboo column 110 is half the height of the engineering bamboo column section 110. A straight-face contact groove 114 corresponding to the shape of the straight-face contact part 124 is machined on the engineering bamboo column 110 to accommodate the inclined contact part 124. The engineering bamboo beam 120 can be joined with the engineering bamboo column 110 individually, or two engineering bamboo beams 120 can be symmetrically joined on both sides of the engineering bamboo column 110.

[0027] The engineered bamboo beam-column connection node also includes a self-tapping screw 130. The self-tapping screw 130 is drilled into the engineered bamboo beam 120 at an angle to the fiber direction of the bamboo beam 120, penetrating the bamboo beam 120 and anchored within the engineered bamboo column 110. The interaction of the inclined contact portion 122, the straight contact portion 124, and the self-tapping screw 130 enhances the initial in-plane stiffness of the node. Optionally, the straight contact portion 124 extends into the engineered bamboo column 110 for half the cross-sectional height of the bamboo column 110, and the drilling direction of the self-tapping screw 130 forms a 45-degree angle with the fiber direction of the bamboo beam 120. The introduction of the self-tapping screw 130, in conjunction with the inclined contact portion 122 and the straight contact portion 124, jointly improves the mechanical properties of the node. Optionally, the self-tapping screw 130 is drilled into the surface of the engineered bamboo beam 120 at a 45-degree angle, ensuring that the screw axis forms a fixed angle with the fiber direction of the beam, thereby optimizing stress distribution. The self-tapping screw 130 is drilled near the beveled contact portion 122 or the straight contact portion 124, penetrating the beam and extending into the interior of the engineered bamboo column 110. The anchorage length meets the minimum requirement of 100 mm to provide sufficient holding force. The self-tapping screw 130 enhances the mechanical interlocking between the bamboo materials through oblique drilling, suppressing the tendency for transverse splitting. This, combined with the increased contact area from the beveled contact portion 122 and the load-bearing support provided by the straight contact portion 124, improves the initial in-plane stiffness and bending capacity of the joint. The out-of-plane stability of the joint is enhanced, avoiding common failure modes in engineered bamboo beam-column bolted joints. Simultaneously, construction is convenient and highly prefabricated. The 45-degree drilling angle of the self-tapping screw 130 facilitates load transfer and reduces stress concentration, while sufficient anchorage length ensures reliability. The overall joint achieves an efficient load path through the cooperation of multiple components.

[0028] Optionally, the engineered bamboo column 110 has a height of 1000 mm and a cross-sectional dimension of 300 mm × 300 mm. The engineered bamboo beam 120 has a length of 650 mm and a cross-sectional dimension of 200 mm × 300 mm. The self-tapping screw 130 has a diameter of 8 mm and a length of 400 mm. The 45-degree beveled section has a hypotenuse length of 200 mm and a cross-sectional width of 50 mm, with the angle between the bevel and the fiber direction of the engineered bamboo beam 120 being 45 degrees. The 90-degree tangential section of the engineered bamboo beam 120 has a cross-sectional height of 200 mm, a cross-sectional width of 50 mm, and a length extending 150 mm into the engineered bamboo column 110. The 45-degree beveled sections are preferably arranged on both sides of the engineered bamboo column 110 and the engineered bamboo beam 120. The 90-degree tangential sections are preferably arranged in the middle or near the middle of the engineered bamboo column 110 and the engineered bamboo beam 120. Then, the engineered bamboo beam 120 and the engineered bamboo column 110 are spliced ​​together. Finally, the self-tapping screws 130 are drilled into the engineering bamboo beams 120 and 110 at a 45-degree angle to the fiber direction of the engineering bamboo beams 2. The anchorage length of the self-tapping screws 130 in the engineering bamboo beams should be no less than 100 mm.

[0029] In this embodiment, the bamboo beam-column connection node, by setting the inclined contact portion 122, allows the bamboo beam 120 and the bamboo column 110 to form a larger surface contact area during connection, increasing the contact area and frictional resistance between the components. This effectively avoids slippage caused by initial gaps in bolted connections during load transfer, thus improving the initial in-plane stiffness of the node. Simultaneously, the straight contact portion 124 further provides bearing support, working in conjunction with the inclined contact portion 122; while the self-tapping screw 130, drilled and anchored at an angle, not only provides additional connection constraint but also, together with the inclined contact, enhances the overall integrity of the node, ensuring the load transfer path and improving the initial stiffness of the node.

[0030] In addition, the present invention also provides a method for manufacturing a bamboo beam-column connection node for engineering.

[0031] like Figure 7 As shown, in one embodiment, a method for fabricating an engineering bamboo beam-column connection node includes the following steps: Step S710: Machine mutually compatible inclined contact parts and straight contact parts on the engineering bamboo column and engineering bamboo beam respectively.

[0032] The engineered bamboo columns and beams are respectively machined with mutually compatible beveled and straight contact parts. The beveled contact parts are machined with a 45-degree beveled section, the length of which is equal to the cross-sectional height of the engineered bamboo beam, and the cross-sectional width is less than or equal to one-quarter of the cross-sectional width of the engineered bamboo column. The straight contact parts are machined with a 90-degree tangent section, the height of which is equal to the cross-sectional height of the engineered bamboo beam, and the cross-sectional width is less than or equal to one-quarter of the cross-sectional width of the engineered bamboo column. The length of the cross-section extending into the engineered bamboo column is equal to half the cross-sectional height of the engineered bamboo column. The beveled contact parts are symmetrically arranged on both sides of the beam-column joint, and the straight contact parts are arranged in the middle position.

[0033] Step S720: The processed engineering bamboo beams and engineering bamboo columns are spliced ​​together through the inclined contact part and the straight contact part.

[0034] The processed engineering bamboo beams and engineering bamboo columns are precisely spliced ​​together through inclined and straight contact parts to ensure a tight fit between the contact surfaces.

[0035] Step S730: Drill the self-tapping screws into the engineered bamboo beam at an angle to the direction of the engineered bamboo fiber so that they penetrate the engineered bamboo beam and are anchored inside the engineered bamboo column.

[0036] Self-tapping screws are drilled into the engineered bamboo beam at a 45-degree angle to the fiber direction, penetrating the beam and anchoring it within the bamboo column. The anchorage length of the self-tapping screw in the bamboo column is no less than 100 mm. This method improves load transfer efficiency by expanding the beam-column contact area through the beveled contact portion, providing primary load-bearing support through the straight contact portion, and enhancing the overall integrity of the joint through the self-tapping screw. The synergistic effect of these three factors significantly improves the initial in-plane stiffness and bending capacity of the joint. Simultaneously, the beveled contact design avoids bolt gap issues, and the oblique insertion of the self-tapping screw effectively prevents cross-grain splitting of the bamboo. The overall manufacturing process facilitates prefabrication construction, improves assembly efficiency, and enhances the out-of-plane stability of the joint.

[0037] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0038] The above-described embodiments are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. An engineered bamboo beam-column connection node, comprising an engineered bamboo column and an engineered bamboo beam connected with the engineered bamboo column, characterized in that, at least one inclined surface contact part and one straight surface contact part are respectively arranged at the joint part of the engineered bamboo column and the engineered bamboo beam, the inclined surface of the inclined surface contact part forms an acute angle with the fiber direction of the engineered bamboo beam; the engineered bamboo beam is spliced with the engineered bamboo column through the inclined surface contact part and the straight surface contact part; a self-tapping screw is further included, which is drilled in a direction inclined to the fiber direction of the engineered bamboo beam, penetrates the engineered bamboo beam and is anchored in the engineered bamboo column, so as to improve the initial stiffness in the plane of the node through the mutual cooperation of the inclined surface contact part, the straight surface contact part and the self-tapping screw.

2. The engineered bamboo beam-column connection node of claim 1, wherein, The angle between the inclined surface of the inclined surface contact part and the fiber direction of the engineered bamboo beam is 45 degrees.

3. The engineered bamboo beam-column connection node of claim 2, wherein, The inclined surface contact part is at least two and symmetrically arranged on both sides of the joint part of the engineered bamboo beam and the engineered bamboo column, and the straight surface contact part is at least one and arranged between the inclined surface contact parts on both sides.

4. The engineered bamboo beam-column connection node of claim 3, wherein, The length of the inclined side of the projection of the inclined surface of the inclined surface contact part on the engineered bamboo beam is equal to the cross-sectional height of the engineered bamboo beam.

5. The engineered bamboo beam-column connection node of claim 3, wherein, The cross-sectional width of the inclined surface contact part is less than or equal to one fourth of the cross-sectional width of the engineered bamboo column.

6. The engineered bamboo beam-column connection node of claim 3, wherein, The length of the straight surface contact part extending into the engineered bamboo column is one third to two thirds of the cross-sectional height of the engineered bamboo column.

7. The engineered bamboo beam-column connection node of claim 3, wherein, The length of the straight surface contact part extending into the engineered bamboo column is one half of the cross-sectional height of the engineered bamboo column.

8. The engineered bamboo beam-column connection node of claim 1, wherein, The angle between the drilling direction of the self-tapping screw and the fiber direction of the engineered bamboo beam is 45 degrees.

9. The engineered bamboo beam-column connection node according to any one of claims 1 to 8, wherein, The anchoring length of the self-tapping screw in the engineered bamboo column is not less than 100 mm.

10. A method for manufacturing an engineered bamboo beam-column connection node, for manufacturing the engineered bamboo beam-column connection node according to any one of claims 1 to 9, characterized in that, It comprises: processing the inclined surface contact part and the straight surface contact part which are mutually adapted on the engineered bamboo column and the engineered bamboo beam respectively; splicing the processed engineered bamboo beam and the engineered bamboo column through the inclined surface contact part and the straight surface contact part; drilling the self-tapping screw in a direction inclined to the fiber direction of the engineered bamboo beam, so that it penetrates the engineered bamboo beam and is anchored in the engineered bamboo column.

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