Prefabricated bamboo concrete solid beam
By using prefabricated bamboo-concrete solid beam structures, combining the characteristics of bamboo and concrete, the high carbon emissions and high energy consumption of reinforced concrete beams are solved, achieving low-carbon production and efficient thermal insulation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- EAST CHINA UNIV OF TECH
- Filing Date
- 2025-06-16
- Publication Date
- 2026-07-31
AI Technical Summary
Existing reinforced concrete beams have problems of high carbon emissions and high energy consumption during production and operation, especially the lack of thermal insulation products for load-bearing components such as beams.
The prefabricated bamboo-concrete solid beam structure includes a foamed concrete insulation outer shell, a bamboo mesh layer, a concrete load-bearing layer, and an aerated concrete inner core. By combining bamboo and concrete, carbon emissions are reduced and thermal insulation performance is improved.
It achieves low-carbon production and efficient thermal insulation, reduces building energy consumption, and promotes the development of low-carbon buildings.
Smart Images
Figure CN224578955U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of low-carbon building technology, and in particular to a prefabricated bamboo-based solid concrete beam. Background Technology
[0002] For a long time, reinforced concrete has been the primary material used in the construction industry. While this structure boasts high strength and stability, it also presents the problem of high carbon emissions. Firstly, its production requires a large amount of energy, generating substantial carbon dioxide emissions. Secondly, its high thermal conductivity results in significant energy consumption for heating and cooling during operation. To reduce carbon emissions, it is necessary to develop building materials that use less cement and steel reinforcement while providing thermal insulation. Currently, a large number of insulated wall materials have been developed, but insulated products are rarely seen for load-bearing components like beams.
[0003] Studies have shown that bamboo possesses high strength, is easy to process, and has significantly lower thermal conductivity than steel, while also posing no carbon emission issues. Other research indicates that foamed concrete has low cement consumption, low density, good thermal insulation performance, and is easy to pour and construct; aerated concrete and foamed concrete have even lower carbon emissions and are easier to prefabricate. Therefore, this presents the possibility of comprehensively utilizing bamboo, aerated concrete, and foamed concrete to produce low-carbon and environmentally friendly insulated beam components. Utility Model Content
[0004] The purpose of this invention is to provide a prefabricated bamboo-based solid concrete beam that has the dual advantages of low carbon emissions during production and thermal insulation during operation, thereby promoting the development of low-carbon buildings.
[0005] To achieve the above objectives, this utility model provides a prefabricated bamboo-based solid concrete beam. The solid concrete beam comprises, from the outside to the inside, a foamed concrete insulation outer shell, a bamboo mesh layer, a concrete load-bearing layer, and an aerated concrete inner core. The concrete load-bearing layer includes longitudinal reinforcing bars, bamboo stirrups, and filling concrete poured outside the longitudinal reinforcing bars and stirrups.
[0006] Preferably, the thickness of the foamed concrete insulation outer shell layer is 40-100mm, and the density is 1000-1500kg / m³. 3 Its strength is not less than 5MPa and its thermal conductivity is not greater than 0.35W / (m·K).
[0007] Preferably, the bamboo mesh layer is woven from cross-woven horizontal and vertical bamboo strips, with the width of the bamboo strips being 5-10mm and the thickness being 1-3mm. The weaving gap between the horizontal and vertical bamboo strips is no greater than 0.3mm × 0.3mm.
[0008] Preferably, the longitudinal reinforcing bars include longitudinal reinforcing steel bars and longitudinal reinforcing bamboo bars. The longitudinal reinforcing steel bars are placed inside the four corners of the bamboo bar stirrups, and the longitudinal reinforcing bamboo bars are placed inside the bamboo bar stirrups. Both the longitudinal reinforcing steel bars and the longitudinal reinforcing bamboo bars are tied to the bamboo bar stirrups.
[0009] Longitudinal reinforcing bars shall be threaded steel bars with a diameter greater than 16mm. The cross-section of the longitudinal reinforcing bamboo bars shall be a rectangle with a length of 40-80mm and a width of 20-44mm. The horizontal clear distance between the longitudinal reinforcing bars and the longitudinal reinforcing bamboo bars, as well as the horizontal clear distance between the longitudinal reinforcing bamboo bars, shall not be less than 40mm.
[0010] Preferably, the outer periphery of the longitudinally stressed bamboo rib is provided with a first bamboo fiber yarn wound clockwise in a spiral. The diameter of the first bamboo fiber yarn is 2-5mm, the angle between the first bamboo fiber yarn and the longitudinal axis of the bamboo rib cross section is 13°-18°, the pitch of the first bamboo fiber yarn is 10-20mm, and the surface of the first bamboo fiber yarn is brushed with epoxy resin.
[0011] Preferably, the filling concrete comprises concrete and bamboo fiber, wherein the concrete has a strength of not less than 30 MPa, and the volume fraction of bamboo fiber is 0.5%-1% of the concrete.
[0012] Preferably, the bamboo fiber has a diameter of 100-300 μm, a length of 30-45 mm, a tensile strength of 1.3-1.6 GPa, an elastic modulus of 69-72 GPa, and a density of 1.33-1.4 g / cm³. 3 .
[0013] Preferably, the bamboo reinforcement has two rows of grooves along its length on both the inner and outer sides. The grooves are filled with second bamboo fiber yarn, quartz sand and epoxy resin. The grooves have protrusions formed by the second bamboo fiber yarn, quartz sand and epoxy resin. The second bamboo fiber yarn is wound clockwise in a spiral along the length of the bamboo reinforcement.
[0014] The cross-sectional length of the bamboo reinforcement stirrups is 20-24mm and the cross-sectional width is 10-12mm. The bamboo reinforcement stirrups are set along the longitudinal direction of the reinforcing bars, and the spacing is 80-200mm. The thickness of the concrete filling on the outer side of the top of the bamboo reinforcement stirrups is not less than 20mm.
[0015] The angle between the groove direction and the length direction of the bamboo reinforcement is 42°-48°, the groove spacing is 12-15mm, the depth is 2-3mm, and the width is 4-6mm.
[0016] The diameter of the second bamboo fiber yarn is 2-5mm, and its pitch is 10-20mm;
[0017] The protrusion height is 1-1.5mm.
[0018] Preferably, the aerated concrete core is elliptical, with the ratio of its major axis to its minor axis equal to the height-to-width ratio of the concrete load-bearing layer. The distance between its four vertices and the bamboo reinforcement stirrups is not less than 50mm, and its density is 400-600kg / m³. 3 Its strength is not less than 1 MPa, and its thermal conductivity is not greater than 0.15 W / (m·K);
[0019] The aerated concrete core has a perforation, the center of which is located at the midpoint of the major axis radius of the aerated concrete core. The wall of the perforation is made of PVC pipe, and the diameter of the perforation is 15-25mm.
[0020] Therefore, the present invention, employing the aforementioned prefabricated bamboo-concrete solid beam, has the following beneficial effects:
[0021] (1) Replacing some of the steel bars with bamboo not only makes it easier to process, but also reduces the self-weight of solid beams, reduces carbon emissions in the production process, and promotes the development of low-carbon buildings.
[0022] (2) Adding bamboo fiber and foam to concrete reduces the thermal conductivity of concrete, which can play a role in heat insulation and reduce energy consumption during operation.
[0023] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description
[0024] Figure 1 This is a cross-sectional view of a first embodiment of a prefabricated bamboo-concrete solid beam according to this utility model;
[0025] Figure 2 This is a schematic diagram of the bamboo stirrups in Embodiment 1 of the prefabricated bamboo concrete solid beam of this utility model.
[0026] Figure Labels
[0027] 1. Foamed concrete insulation outer shell; 2. Bamboo mesh layer; 3. Concrete load-bearing layer; 4. Aerated concrete inner core; 5. Longitudinal load-bearing reinforcement; 6. Bamboo reinforcement stirrups; 7. Filling concrete; 8. Longitudinal load-bearing steel bars; 9. Longitudinal load-bearing bamboo reinforcement; 10. Perforation; 11. Grooving; 12. Second bamboo fiber yarn. Detailed Implementation
[0028] The technical solution of this utility model will be further described below with reference to the accompanying drawings and embodiments.
[0029] Unless otherwise defined, the technical or scientific terms used in this utility model shall have the ordinary meaning understood by one of ordinary skill in the art to which this utility model pertains. The terms "first," "second," and similar terms used in this utility model do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.
[0030] Both the first and second bamboo fiber yarns are 40-count bamboo fiber yarns produced by Qingdao Zhengxinlong Textile Technology Co., Ltd.
[0031] Example 1
[0032] like Figure 1 As shown, this utility model provides a prefabricated bamboo-based solid concrete beam, which, from the outside to the inside, includes a foamed concrete insulation outer shell layer 1, a bamboo mesh layer 2, a concrete load-bearing layer 3, and an aerated concrete inner core 4. The foamed concrete insulation outer shell layer 1 provides good thermal insulation performance, helping to reduce energy loss in buildings. The bamboo mesh layer 2 enhances the overall strength and toughness of the structure, while using renewable bamboo materials, making it environmentally friendly and economical. The concrete load-bearing layer 3 serves as the main load-bearing component, ensuring the stability and load-bearing capacity of the solid beam structure. The aerated concrete inner core 4 reduces the overall weight while maintaining good thermal and sound insulation performance.
[0033] The thickness of the foamed concrete insulation outer shell layer 1 is 40mm, and the density is 1200kg / m³. 3 It has a strength of 8MPa and a thermal conductivity of 0.25W / (m·K). It is made of foam and concrete, which reduces the thermal conductivity of concrete and has a good thermal insulation effect.
[0034] The second layer of bamboo mesh is woven from cross-woven horizontal and vertical bamboo strips. The width of the bamboo strips is 7mm, the thickness is 3mm, and the weave gap size of the horizontal and vertical bamboo strips is 0.2mm×0.2mm. The bamboo strips need to be pre-treated for preservation, that is, soaked in borax solution and then dried.
[0035] The concrete load-bearing layer 3 includes longitudinal reinforcing bars 5, bamboo-reinforced stirrups 6, and infill concrete 7 poured outside the longitudinal reinforcing bars 5 and stirrups. The combination of longitudinal reinforcing bars 5 and bamboo-reinforced stirrups 6 enhances the beam's bending resistance and overall stability, while the infill concrete 7 poured on the outside further strengthens the structure.
[0036] The longitudinal reinforcing bars 5 include longitudinal reinforcing steel bars 8 and longitudinal reinforcing bamboo bars 9. The longitudinal reinforcing steel bars 8 are placed inside the four corners of the bamboo bar stirrups 6, and the longitudinal reinforcing bamboo bars 9 are placed inside the bamboo bar stirrups 6. The longitudinal reinforcing steel bars 8 provide high tensile strength, while the longitudinal reinforcing bamboo bars 9 have good toughness. Both are tied to the bamboo bar stirrups 6 to enhance the stability and load-bearing capacity of the overall structure.
[0037] The longitudinal reinforcing bars 8 are made of 18mm diameter threaded steel bars. The longitudinal reinforcing bamboo bars 9 have a cross-section of 40mm long and 20mm wide. The horizontal net spacing between the longitudinal reinforcing bars 8 and the longitudinal reinforcing bamboo bars 9, as well as the horizontal net spacing between the longitudinal reinforcing bamboo bars 9, are both 50mm.
[0038] The longitudinally stressed bamboo reinforcement 9 is surrounded by a first bamboo fiber thread wound clockwise in a spiral. The angle between the first bamboo fiber thread and the longitudinal axis of the bamboo reinforcement section is 15°, and the pitch of the first bamboo fiber thread is 13mm. This optimizes stress distribution and improves shear resistance. The diameter of the first bamboo fiber thread is 3mm, and its surface is coated with epoxy resin, which improves the durability and corrosion resistance of the first bamboo fiber thread, while also enhancing its adhesion to concrete.
[0039] like Figure 2 As shown, the bamboo reinforcement stirrup 6 has a cross-sectional length of 24mm and a cross-sectional width of 10mm. The bamboo reinforcement stirrup 6 is arranged along the longitudinal reinforcing bar 5 with a spacing of 100mm. The top outer side of the bamboo reinforcement stirrup 6 is filled with 22mm thick concrete 7, enhancing the top's compressive strength and overall stability. The bottom and left and right sides are not filled with concrete 7, but are provided with a foamed concrete insulation shell layer 1. Two rows of grooves 11 are provided along the length direction on both the inner and outer sides of the bamboo reinforcement stirrup 6. The angle between the groove direction 11 and the length direction of the bamboo reinforcement stirrup 6 is 45°, which optimizes stress distribution and improves shear resistance. The grooves 11 are spaced 13mm apart, 2mm deep, and 4mm wide. The grooves 11 are filled with a second bamboo fiber yarn 12, quartz sand, and epoxy resin. The grooves 11 have protrusions formed by the second bamboo fiber yarn 12, quartz sand, and epoxy resin, with a height of 1mm, increasing the contact area with the filling concrete 7 and providing additional strength, wear resistance, and durability. The second bamboo fiber yarn 12 is wound clockwise in a spiral along the length of the bamboo reinforcement 6. The diameter of the second bamboo fiber yarn 12 is 4mm and its pitch is 13mm.
[0040] The filler concrete 7 consists of concrete and bamboo fiber. The concrete has a strength of 40 MPa, and the volume fraction of bamboo fiber is 1% of the concrete. The bamboo fiber has a diameter of 200 μm, a length of 30 mm, a tensile strength of 1.5 GPa, an elastic modulus of 71 GPa, and a density of 1.36 g / cm³. 3 Bamboo fiber requires pretreatment to enhance its spatial dispersibility and interfacial bonding performance with concrete. The specific steps include: Cutting purchased 4-5 year old bamboo with a diameter at breast height (DBH) of 100mm or more into strips 340mm long, 15mm wide, and 8mm thick; softening the bamboo strips by steaming them in a boiling water bath for 1 hour; then microwaving the softened bamboo strips for 15 minutes to remove moisture and improve fiber dispersibility, preparing for subsequent chemical treatment. The physically treated bamboo fiber is then soaked in a mixed solution of 30% hydrogen peroxide and 88% formic acid to remove lignin and hemicellulose. Subsequently, it is soaked in a 2.0g / L polydopamine solution, dried in a hot air circulating kiln to improve interfacial bonding performance, and finally soaked in epoxy resin and air-dried to enhance weather resistance and service life.
[0041] The aerated concrete core 4 is elliptical, with the ratio of its major axis to its minor axis equal to the height-to-width ratio of the concrete load-bearing layer 3. The distance from its four vertices to the bamboo reinforcement stirrups 6 is 60mm, and its density is 450kg / m³. 3 It has a strength of 2.3 MPa and a thermal conductivity of 0.12 W / (m·K).
[0042] The aerated concrete core 4 has a perforation 10 inside. The center of the perforation 10 is located at the midpoint of the major axis radius of the aerated concrete core 4. The wall of the perforation 10 is made of PVC pipe and the diameter of the perforation 10 is 20mm. The perforation 10 can be used to fix the position of the core during production, can be used for lifting during installation, and also plays a role in heat insulation, reducing the thermal conductivity of the solid beam.
[0043] Therefore, this utility model adopts the above-mentioned prefabricated bamboo concrete solid beam, which has the dual advantages of low carbon emissions during production and thermal insulation during operation, thus promoting the development of low-carbon buildings.
[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solution of this utility model, and these modifications or equivalent substitutions cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of this utility model.
Claims
1. A fabricated bamboo concrete solid beam, characterized in that, The solid concrete beam consists of, from the outside to the inside, a foamed concrete insulation shell layer, a bamboo mesh layer, a concrete load-bearing layer, and an aerated concrete core. The concrete load-bearing layer includes longitudinal reinforcing bars, bamboo stirrups, and filling concrete poured outside the longitudinal reinforcing bars and stirrups.
2. The fabricated bamboo concrete solid beam according to claim 1, characterized in that, The thickness of the foam concrete thermal insulation outer shell layer is 40-100mm, the density is 1000-1500kg / m 3 , the strength is not less than 5MPa, and the thermal conductivity is not greater than 0.35W / (m·K).
3. The fabricated bamboo concrete solid beam according to claim 1, characterized in that, The bamboo mesh layer is woven from cross-woven horizontal and vertical bamboo strips. The width of the bamboo strips is 5-10mm, and the thickness is 1-3mm. The weaving gap between the horizontal and vertical bamboo strips is no greater than 0.3mm×0.3mm.
4. The fabricated bamboo concrete solid beam according to claim 1, wherein, The longitudinal reinforcing bars include longitudinal reinforcing steel bars and longitudinal reinforcing bamboo bars. The longitudinal reinforcing steel bars are placed inside the four corners of the bamboo bar stirrups, and the longitudinal reinforcing bamboo bars are placed inside the bamboo bar stirrups. Both the longitudinal reinforcing steel bars and the longitudinal reinforcing bamboo bars are tied to the bamboo bar stirrups. Longitudinal reinforcing bars shall be threaded steel bars with a diameter greater than 16mm. The cross-section of the longitudinal reinforcing bamboo bars shall be a rectangle with a length of 40-80mm and a width of 20-44mm. The horizontal clear distance between the longitudinal reinforcing bars and the longitudinal reinforcing bamboo bars, as well as the horizontal clear distance between the longitudinal reinforcing bamboo bars, shall not be less than 40mm.
5. A prefabricated bamboo-concrete solid beam according to claim 4, characterized in that, The outer periphery of the longitudinally stressed bamboo rib is provided with a first bamboo fiber yarn wound clockwise in a spiral. The diameter of the first bamboo fiber yarn is 2-5mm, the angle between the first bamboo fiber yarn and the longitudinal axis of the bamboo rib cross section is 13°-18°, the pitch of the first bamboo fiber yarn is 10-20mm, and the surface of the first bamboo fiber yarn is brushed with epoxy resin.
6. The fabricated bamboo concrete solid beam according to claim 1, wherein, The filling concrete consists of concrete and bamboo fiber, with the concrete strength not less than 30 MPa and the volume fraction of bamboo fiber being 0.5%-1% of the concrete.
7. The fabricated bamboo concrete solid beam according to claim 1, wherein, The bamboo reinforcement has two rows of grooves along its length on both the inner and outer sides. The grooves are filled with second bamboo fiber yarn, quartz sand and epoxy resin. The grooves have protrusions formed by the second bamboo fiber yarn, quartz sand and epoxy resin. The second bamboo fiber yarn is wound clockwise in a spiral along the length of the bamboo reinforcement. The cross-sectional length of the bamboo reinforcement stirrups is 20-24mm and the cross-sectional width is 10-12mm. The bamboo reinforcement stirrups are set along the longitudinal direction of the reinforcing bars, and the spacing is 80-200mm. The thickness of the concrete filling on the outer side of the top of the bamboo reinforcement stirrups is not less than 20mm. The angle between the groove direction and the length direction of the bamboo reinforcement is 42°-48°, the groove spacing is 12-15mm, the depth is 2-3mm, and the width is 4-6mm. The diameter of the second bamboo fiber yarn is 2-5mm, and its pitch is 10-20mm; The protrusion height is 1-1.5mm.
8. The fabricated bamboo concrete solid beam according to claim 1, wherein, The inner core of the aerated concrete is elliptical, the ratio of the long axis to the short axis is equal to the height-width ratio of the stress layer of the concrete, the distance from the four vertexes to the bamboo reinforcement is not less than 50mm, the density is 400-600kg / m 3 , the strength is not less than 1MPa, and the thermal conductivity is not greater than 0.15W / (m·K). The aerated concrete core has a perforation, the center of which is located at the midpoint of the major axis radius of the aerated concrete core. The wall of the perforation is made of PVC pipe, and the diameter of the perforation is 15-25mm.