A bamboo-based composite structural column based on co-extrusion technology
By introducing a concrete layer, steel pipe, and bamboo-based composite material surrounding the bamboo-based composite structure column, and setting steel bars in the bamboo-based composite material surrounding, the problems of easy failure and stress concentration in bamboo-plastic composite frame structures are solved, realizing a high-strength, environmentally friendly, and economical building material solution.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SOUTH CHINA AGRICULTURAL UNIVERSITY
- Filing Date
- 2025-05-29
- Publication Date
- 2026-07-31
AI Technical Summary
Existing bamboo-plastic composite frame structure columns are prone to failure under compression and eccentric loads, have insufficient bending resistance, and are prone to stress concentration, failing to meet complex stress requirements and environmental protection requirements.
A composite structure consisting of a concrete layer, a steel pipe, and a bamboo-based composite material is manufactured using co-extrusion technology. Reinforcing bars are placed inside the bamboo-based composite material, and the reinforcing bars and steel pipe are integrally formed by co-extrusion. An angular convex structure is used for reinforcement and fixation to form a solid column cross section.
It improves the structure's resistance to compression, tension, and bending, enhances its corrosion resistance and environmental friendliness, reduces costs, improves the overall strength and toughness of the structure, and has good energy dissipation capacity and seismic performance.
Smart Images
Figure CN224578957U_ABST
Abstract
Description
Technical Field
[0001] This invention relates to structural load-bearing columns, specifically to a bamboo-based composite structural column based on co-extrusion technology. Background Technology
[0002] In the field of building structures, columns are key load-bearing components, and their performance is crucial to the safety and stability of buildings. With the development of the construction industry and the increasing demand for environmentally friendly and high-performance materials, the limitations of traditional column structures and materials are becoming increasingly apparent.
[0003] Currently, the most widely used structural materials are reinforced concrete columns, steel columns, and wooden columns. However, reinforced concrete columns are criticized for their heavy weight, poor fire resistance, and environmental friendliness. Steel columns, on the other hand, have poor corrosion resistance and fire resistance and are expensive. Wooden columns have limited strength, and timber resources are not sustainable. Therefore, it is necessary to explore new materials for structural load-bearing columns, such as bamboo.
[0004] CN219690895U discloses a co-extruded bamboo-plastic composite frame structure column as a structural load-bearing column, comprising a bamboo-plastic inner ring, a bamboo-plastic outer ring, and bamboo-plastic partitions. The tubular bamboo-plastic inner ring is located on the inner side, and the tubular bamboo-plastic outer ring is located on the outer side. Multiple layers of bamboo-plastic partitions are located between the outer and inner rings. The outer end of each partition connects to the inner side of the outer ring, and the inner end connects to the outer side of the inner ring, thus forming a lattice structure between the inner and outer rings. In Example 16, this frame structure column, combined with steel pipes and concrete through the bamboo-plastic inner and outer rings and partitions, has the following problems: 1. The bamboo-plastic partitions are relatively thin and easily crushed during compression, leading to column failure; 2. In actual engineering, pure axial compression is almost non-existent, and this frame column may have insufficient bending resistance under eccentric loads; 3. The lattice structure makes stress concentration prone to occur.
[0005] To address these issues, it is necessary to improve the load-bearing columns of bamboo structures to meet the requirements for strength and rigidity, as well as to satisfy users' needs in terms of corrosion resistance and cost of use. Summary of the Invention
[0006] In view of the technical problems existing in the prior art, the purpose of this invention is to provide a bamboo-based composite structure column based on co-extrusion technology that meets complex stress requirements.
[0007] To achieve the above objectives, the present invention adopts the following technical solution:
[0008] A bamboo-based composite structure column based on co-extrusion technology, serving as a structural load-bearing column, comprises, from the inside out, a concrete layer, a steel pipe, and a bamboo-based composite material surrounding it, with a ring of reinforcing bars inside the bamboo-based composite material surrounding the steel pipe.
[0009] As a preferred option, the outer ring of the bamboo-based composite material is square, the inner ring is circular, the steel pipe is round, and the cross-section of the reinforcing bars is circular; multiple reinforcing bars are arranged in a square ring; the steel pipe is located at the center of the bamboo-based composite material.
[0010] As a preferred option, a ring of steel bars and a bamboo-based composite material are integrally formed using co-extrusion technology.
[0011] As a preferred option, the bamboo-based composite material has multiple steel bar holes in its outer casing. The inner wall of the steel bar holes has protrusions, and the steel bars are inserted into the steel bar holes, with the protrusions pressing the steel bars tightly against each other.
[0012] As a preferred option, a steel pipe hole is set in the center of the outer casing of the bamboo-based composite material. The inner wall of the steel pipe hole has multiple corner protrusions. The steel pipe is inserted into the steel pipe hole, and the corner protrusions press the steel pipe tightly against it.
[0013] As a preferred embodiment, there are multiple angular protrusions, which are evenly distributed around the inner circumference of the steel pipe hole, and the angular protrusions penetrate the length of the solid column; the cross-section of the angular protrusions is semi-circular.
[0014] As a preferred option, the bamboo-based composite material outer casing is manufactured by co-extrusion molding.
[0015] As a preferred option, the four corners of the outer ring surrounding the bamboo-based composite material are rounded.
[0016] As a preferred embodiment, the protrusion height of the raised portion is 1-3mm.
[0017] As a preferred option, the protrusion height of the convex angle is 1-5mm.
[0018] The principle of this invention is to improve the structure of the bamboo-based load-bearing column by using bamboo-based composite material as the outer layer and adding a ring of steel bars inside the outer layer. At the same time, the load-bearing column is designed as a solid structure, which gives the load-bearing column better performance, not only meeting the requirements of complex stress, but also meeting the requirements of environmentally friendly buildings, corrosion resistance, and low cost.
[0019] The present invention has the following advantages:
[0020] 1. High strength and high toughness: The bamboo-based composite material, as the outer layer, possesses a unique fiber structure that endows the column with excellent tensile and shear strength, enhancing the overall strength and toughness of the column. Working in conjunction with the reinforcing steel, when subjected to tensile forces, the steel and bamboo-based composite material work together to effectively disperse stress, improve the column's tensile strength, and prevent structural failure due to tension.
[0021] 2. Excellent compressive strength: The internal concrete filling provides the main compressive strength of the structure, and the compressive performance of the concrete is further enhanced under the constraint of the steel pipe. The constraint of the steel pipe on the concrete puts the concrete in a triaxial compression state under pressure, improving the compressive strength and deformation capacity of the concrete, enabling it to withstand greater axial pressure and ensuring the stability of the column under heavy loads.
[0022] 3. Excellent energy dissipation capacity: Under dynamic loads such as earthquakes, the interaction between bamboo-based composite materials, reinforcing bars, steel pipes, and concrete can effectively absorb and dissipate energy. The yielding deformation of the steel pipes, the fiber tensioning and fracture of the bamboo-based composite materials, and the crack propagation in the concrete can convert externally input energy into internal deformation energy, thereby improving the seismic performance of the structure.
[0023] 4. The cross-section of this structure adopts a solid structure, which avoids the column failure caused by the material being too thin and being crushed during the compression process.
[0024] 5. The corners of the solid column section are rounded, which can reduce the stress concentration at the corners during the loading process.
[0025] 6. The solid column is reinforced with steel bars. The protrusions on the inner surface of the steel bar holes interlock and fix with the steel bars. The bamboo-based composite material and the steel bars work together to improve the overall bending resistance of the structure and improve the ductility of the column.
[0026] 7. The corner protrusions of the solid column are located on the outer surface of the steel pipe and are equidistantly distributed along the circumference of the steel pipe, penetrating the height direction of the composite structure solid column. This can fix the internal steel pipe, reduce the possibility of slippage, and improve the ability of materials to cooperate with each other.
[0027] 8. The steel bars and bamboo-based composite material surrounding the solid column can be integrally formed using co-extrusion technology, which reduces the relative slippage between the steel bars and the steel bar holes, improves the overall structure, and enhances the structural durability.
[0028] 9. The convex corner extends along the entire length of the solid column to provide sufficient fixation and support. Attached Figure Description
[0029] Figure 1 This is a cross-sectional view of a bamboo-based composite structure column based on co-extrusion technology, as described in Example 1.
[0030] Figure 2 This is a three-dimensional view of a bamboo-based composite structure column based on co-extrusion technology, as described in Example 1.
[0031] Figure 3 This is a three-dimensional structural schematic diagram of a bamboo-based composite structure combined column based on co-extrusion technology, as described in Example 1.
[0032] Figure 4 This is a cross-sectional view of a bamboo-based composite structure column based on co-extrusion technology, as described in Example 1.
[0033] Figure 5 This is an exploded view of a bamboo-based composite structure column based on co-extrusion technology, as described in Example 1.
[0034] In the diagram, 1-bamboo-based composite material outer casing, 2-steel reinforcement, 3-steel pipe, 4-concrete layer, 5-corner convex, 6-arc column corner. Detailed Implementation
[0035] The present invention will now be described in further detail with reference to specific embodiments.
[0036] Bamboo-based composites are high-performance composite materials made primarily of bamboo, combined with high-performance reinforcing materials such as resin and fibers (e.g., glass fiber, carbon fiber). They are manufactured using processes like prepreg technology, vacuum infusion, and compression molding. This material can be produced into products of various shapes and sizes using multiple processes, offering simple processing, low cost, and surface treatment options. It inherently provides heat and sound insulation, and the composite effect is even more significant, exhibiting higher strength, stiffness, and durability. The addition of other materials enhances its mechanical properties, making it suitable for applications requiring high resistance to compression and bending.
[0037] The bamboo-based composite material in this embodiment is a biodegradable composite material with a bamboo powder mass ratio of more than 65% and a plastic mass ratio of less than 30%, belonging to a bamboo powder high-filler composite material.
[0038] Example 1
[0039] A bamboo-based composite structural column based on co-extrusion technology, serving as a load-bearing structural column, comprises, from the inside out, a tightly packed concrete layer, a steel pipe, and an outer enclosure of bamboo-based composite material. A ring of reinforcing bars is placed within the outer enclosure of the bamboo-based composite material, and this ring of reinforcing bars surrounds the steel pipe. In this embodiment, concrete is poured into the steel pipe to form a concrete layer, and the concrete is constrained within the core area of the composite structural column by the steel pipe.
[0040] The bamboo-based composite material is surrounded by a square outer ring and a circular inner ring. The steel pipe is round, and the reinforcing bars have a circular cross-section. Multiple reinforcing bars are arranged in a square ring. The steel pipe is located at the center of the bamboo-based composite material. In this embodiment, there are 16 reinforcing bars.
[0041] A ring of steel bars and bamboo-based composite material are integrally formed using co-extrusion technology.
[0042] A steel pipe hole is set in the center of the bamboo-based composite material. The inner wall of the steel pipe hole has multiple corner protrusions. The steel pipe is inserted into the steel pipe hole, and the corner protrusions press the steel pipe tightly.
[0043] There are multiple angular protrusions, evenly distributed around the inner circumference of the steel pipe hole, and the angular protrusions penetrate the length of the solid column; the cross-section of the angular protrusions is semi-circular. In this embodiment, there are six angular protrusions.
[0044] The four corners of the outer ring surrounding the bamboo-based composite material are rounded.
[0045] The height of the protrusion is 1-3mm. In this embodiment, it is 1mm.
[0046] The protrusion height of the convex corner is 1-5mm. In this embodiment, it is 1.5mm.
[0047] Example 2
[0048] The bamboo-based composite material outer casing has multiple steel bar holes, and the inner wall of each hole has a protrusion. The steel bars are inserted into the holes, and the protrusions hold the steel bars in place. In other words, the steel bars and the bamboo-based composite material outer casing are assembled together.
[0049] The bamboo-based composite material outer casing is manufactured through co-extrusion molding.
[0050] The parts not mentioned in this embodiment are the same as in Embodiment 1.
[0051] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.
Claims
1. A bamboo-based composite structural column based on co-extrusion technology, as a structural load-bearing column, characterized in that: It includes a concrete layer, a steel pipe, and a bamboo-based composite material surrounding it, arranged in a tight sequence from the inside out. A ring of steel bars is set in the bamboo-based composite material surrounding it, and the steel pipe is surrounded by a ring of steel bars.
2. A bamboo-based composite structural composite column based on co-extrusion technology as claimed in claim 1, wherein: The outer ring of the bamboo-based composite material is square, the inner ring is circular, the steel pipe is round, and the cross-section of the reinforcing bars is circular; multiple reinforcing bars are arranged in a square ring; the steel pipe is located at the center of the bamboo-based composite material.
3. A bamboo-based composite structural column based on co-extrusion technology according to claim 2, characterized in that: A ring of steel bars and bamboo-based composite material are integrally formed using co-extrusion technology.
4. A bamboo-based composite structural column based on co-extrusion technology as claimed in claim 2, wherein: The bamboo-based composite material has multiple steel bar holes in its outer casing. The inner wall of the steel bar holes has protrusions. The steel bars are inserted into the steel bar holes, and the protrusions hold the steel bars in place.
5. A bamboo-based composite structure column based on co-extrusion technology according to claim 2, characterized in that: A steel pipe hole is set in the center of the bamboo-based composite material. The inner wall of the steel pipe hole has multiple corner protrusions. The steel pipe is inserted into the steel pipe hole, and the corner protrusions press the steel pipe tightly.
6. A bamboo-based composite structure column based on co-extrusion technology according to claim 5, characterized in that: There are multiple angular protrusions, evenly distributed around the inner circumference of the steel pipe hole, and the angular protrusions penetrate the length of the solid column; the cross-section of the angular protrusions is semi-circular.
7. A bamboo-based composite structure column based on co-extrusion technology according to claim 1, characterized in that: The bamboo-based composite material outer casing is manufactured through co-extrusion molding.
8. A bamboo-based composite structure column based on co-extrusion technology according to claim 2, characterized in that: The four corners of the outer ring surrounding the bamboo-based composite material are rounded.
9. A bamboo-based composite structure column based on co-extrusion technology according to claim 4, characterized in that: The height of the protrusion is 1-3mm.
10. A bamboo-based composite structure column based on co-extrusion technology according to claim 5, characterized in that: The protrusion height of the convex corner is 1-5mm.