Mixed cross-laminated wood connected by bamboo nails

Abstract

The utility model discloses a mixed cross-laminated wood connected by bamboo nails, which mainly comprises discrete laminates, integral laminates and bamboo nails, the discrete laminates are formed by laying dimension materials or plates side by side, and the integral laminates comprise glued solid wood boards, plywood, laminated veneer lumber, directional wood chip boards and bamboo plywood. The preparation method of the mixed orthogonal laminated wood comprises the following steps: (1) assembling or processing discrete type laminates and integral type laminates to a set size; (2) when the mixed orthogonal laminated wood is manufactured, the discrete laminates are arranged on odd-numbered layers, the integral laminates are arranged on even-numbered layers, and adjacent laminates are orthogonally assembled; and (3) the adjacent laminates are connected through bamboo nails at the designated positions according to stress. The rolling shear performance of the cross-laminated wood is remarkably improved, glue joint is replaced by bamboo nail connection between laminates, and the mixed cross-laminated wood has the advantages of being excellent in structural performance, environmentally friendly, low in carbon and the like and can be widely applied to wall panels, floor panels and roof panels of building structures.

Description

Technical Field

[0001] The utility model relates to mixed cross-laminated timber connected with bamboo nails, belonging to the technical field of green building material production. Background Art

[0002] Cross-laminated timber (CLT) is a composite of at least three layers of solid wood planks assembled orthogonally and then pressed together using structural adhesives. CLT has experienced rapid development due to its green, low-carbon, excellent mechanical properties, and high degree of industrialization, and has been widely used in floor slabs, wall panels, and roof panels in multi-story wooden structures. However, due to the natural properties of wood and the characteristics of CLT assembly, when CLT panels are subjected to out-of-plane loads, they often suffer from premature rolling shear failure, which is not conducive to fully utilizing the mechanical properties of the component. In addition, the bonding between adjacent CLT panels also consumes a considerable amount of adhesive, requiring high processing equipment and high manufacturing costs. Therefore, a utility model is being developed to develop a CLT product that is simple to process and prepare, has excellent mechanical properties, and has a prominent low-carbon effect.

[0003] With the development of modern processing technology, various types of metal nails are widely used in wood structures, greatly promoting the development of modern wood structures. However, the presence of metal nails can easily cause a "cold bridge effect" in housing construction, thereby affecting the building's energy-saving effect. In addition, the presence of metal nails will increase the difficulty and cost of recycling wood when houses are demolished and reused. my country has abundant bamboo resources, and bamboo nails are a new type of biomass material connector. Compared with steel nails, the use of bamboo nails can improve the aesthetics of wood structure connections, simplify the connection process, reduce environmental impact, and have strong reversibility and material compatibility. From a sustainable perspective, because bamboo nail fasteners can be easily sawed, the corresponding wood structure products have better recyclability.

[0004] Hybrid cross laminated timber (HCLT), a new type of engineered wood product, differs from traditional CLT in that it uses an even-numbered composite layer of laminated wood, plywood, laminated veneer lumber, oriented strand board, and bamboo plywood, mixed with an odd-numbered discrete layer. This approach optimizes material utilization, improves product mechanical properties, reduces production costs, and broadens its application. This new design optimizes the use of various types of bamboo and wood materials, enhances CLT's rolling shear performance, reduces costs, and reduces the use of adhesives. Utility Model Content

[0005] Purpose of the utility model: In order to solve the problems of traditional cross-laminated timber such as weak rolling and shearing performance of even-numbered layers, high cost due to large amount of glue used, and high requirements for processing equipment, the utility model proposes a hybrid cross-laminated timber connected with bamboo nails. The hybrid cross-laminated timber is composed of small-sized discrete layers combined with integral layers, which are laid in an orthogonal manner and connected with bamboo nails. No pre-drilling is required at the positions of the bamboo nails.

[0006] In order to achieve the above-mentioned purpose, the technical solution provided by the present utility model is:

[0007] A hybrid cross-laminated timber connected by bamboo nails, wherein the total number of layers of the hybrid cross-laminated timber is an odd number of 3 or more, wherein the layer boards of the odd-numbered hybrid cross-laminated timber layers are composed of multiple discrete layer boards, and the layer boards of the even-numbered hybrid cross-laminated timber layers are integral layer boards, and upper and lower adjacent layer boards are laid perpendicular to each other and connected by bamboo nails.

[0008] Preferably, the discrete plywood is formed by laying standard lumber or board materials side by side, and the integral plywood is a glued solid wood board, plywood, laminated veneer lumber, oriented wood board or bamboo plywood.

[0009] Preferably, the discrete layer has a minimum width of 50 mm and a minimum thickness of 12 mm; a maximum width of 150 mm and a maximum thickness of 45 mm; the integral layer has a minimum thickness of 12 mm and a maximum thickness of 45 mm.

[0010] Preferably, the moisture content of the discrete layer plates and the integral layer plates should not be greater than 15%, and the difference in moisture content between adjacent layer plates should not be greater than 5%.

[0011] Preferably, the bamboo nail is a densified nail, one end of the bamboo nail is a cone, and the other end is a round head without a protruding head.

[0012] Preferably, the diameter of the bamboo nail ranges from 2.5 mm to 7.5 mm, and the length ranges from 25 mm to 90 mm.

[0013] A method for preparing hybrid cross-laminated timber connected by bamboo nails, characterized by comprising the following steps:

[0014] Step S1: Determine the size, type, and layout of each layer of cross-laminated timber based on the desired cross-laminated timber size and assembly structure, select the length and diameter of the bamboo nails based on the size of the layers, and determine the corresponding pneumatic gun model and air pressure.

[0015] Step S2, preparing the laminate, flattening and planing the four symmetrical surfaces of the laminate along the length direction, and sawing the two ends vertically;

[0016] Step S3: assembling the laminates. The odd-numbered discrete laminates must be spliced ​​to the designed dimensions in length and width, and the even-numbered integral laminates must be machined to the same dimensions as the odd-numbered laminates.

[0017] Step S4: Laying the layers, using a hydraulic device to press the layers horizontally and ensure that the upper and lower layers fit tightly together, marking the locations of the nail insertion points, which should be located on the center line of the standard material layers;

[0018] Step S5: Debugging the pneumatic nail gun to ensure that the air pressure of the pneumatic gun can ensure smooth driving of the bamboo nails, prevent the upper and lower ends of the bamboo nails from being exposed, and avoid cracking of the laminate;

[0019] Step S6, interlayer assembly, requiring the total number of layers to be an odd number, the layers are laid in alignment from bottom to top, and bamboo nails are used to connect every two adjacent layers. The nailing points of adjacent layers are staggered, and the nails are nailed perpendicular to the panel, and nailed in sequence from one end to the other.

[0020] Beneficial effects:

[0021] 1) The hybrid cross-laminated timber jointed with bamboo nails produced by the present invention is a new type of green building material with low cost, environmental protection and excellent performance, and can be widely used in wall panels, floor panels and roof panels of various types of housing buildings.

[0022] 2) The raw materials used for the hybrid cross-laminated timber of the utility model include domestic fast-growing wood, coniferous wood, and bamboo. The wood and bamboo products used include glued solid wood boards, plywood, veneer laminated timber, oriented wood veneer boards, and bamboo plywood, etc. The scope of rights is wide, and the assembly method can be scientifically designed according to actual needs, thereby realizing the optimal utilization of various biomass materials such as bamboo and wood.

[0023] 3) The utility model adopts bamboo nails as the connection method for adjacent layers, and the hybrid cross-laminated timber formed has a high degree of inter-layer bonding, good integrity, and excellent product appearance quality.

[0024] 4) The raw materials of bamboo, fast-growing wood and some coniferous materials involved in this utility model can all be domestically produced. Through product promotion, it can effectively promote the development of the wood and bamboo industry, expand the scale of the industry, create jobs, and drive the income of related practitioners. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of a hybrid cross-laminated timber structure connected by bamboo nails according to the present invention;

[0026] Figure 2 for Figure 1 Schematic diagram of the middle AA section;

[0027] Figure 3 for Figure 1 Schematic diagram of the middle BB section;

[0028] Figure 4 This is a schematic diagram of the bamboo nail structure of the utility model;

[0029] Figure 5 This is a schematic diagram of the assembly method between layers of the utility model;

[0030] Figure 6 This is a schematic diagram of the vertically arranged and staggered bamboo nails of the utility model;

[0031] Figure 7 This is the final schematic diagram of the utility model with three layers;

[0032] In the figure: 1 is a discrete layer board, 2 is an integral layer board, 3 is a bamboo nail, 4 is the main strength direction of the surface layer, 5 is a bamboo nail connection, 6 is an adjacent layer, and 7 is a vertically staggered bamboo nail connection. DETAILED DESCRIPTION

[0033] The present invention will be further described below with reference to specific embodiments and accompanying drawings:

[0034] Example 1: A bamboo nail-jointed hybrid cross-laminated timber and its preparation method, the structure of which is as follows Figure 1-4 The hybrid cross-laminated timber has dimensions of 3000 mm (length × width × thickness) × 2400 mm (thickness) × 105 mm and is composed of discrete plies 1 (spruce-pine-fir (SPF) lumber), integral plies 2 (laminated veneer lumber) made of domestic fast-growing poplar wood, and bamboo nails 3. Figure 1 The middle arrow indicates the main strength direction of the surface layer of the hybrid orthogonal glued timber. The upper and lower surface layers are SPF, and the middle layer is LVL. The main strength direction 4 of the surface layer is perpendicular to the main strength direction of the middle layer. Adjacent layers 6 are connected by bamboo nails 5. One adjacent three-layer orthogonal unit is connected by two perpendicularly staggered bamboo nails 7.

[0035] Specific size:

[0036] SPF material: cross-sectional dimensions are 35mm x 100mm, made by splicing layers of varying lengths to the set dimensions.

[0037] LVL: length 3000mm, width 2400mm, thickness 35mm.

[0038] Bamboo nails: 5.3mm in diameter and 70mm in length.

[0039] Example 2: A bamboo nail-jointed hybrid cross-laminated timber and its preparation method, the structure of which is as follows Figure 1The hybrid cross-laminated timber has dimensions of length × width × thickness = 3200 mm × 3200 mm × 120 mm and is composed of discrete plywood 1: domestic fast-growing poplar wood boards, integral plywood 2: bamboo plywood, and bamboo nails 3. The raw material of the bamboo plywood is domestic moso bamboo. Figure 1 The middle arrow indicates the main strength direction of the surface layer of the hybrid orthogonal glued timber. The upper and lower surface layers are made of domestic fast-growing poplar wood boards, and the middle layer is made of bamboo plywood. The main strength direction 4 of the surface layer is perpendicular to the main strength direction of the middle layer. Adjacent layers 6 are connected using bamboo nails 5. One of the adjacent three-layer orthogonal units is connected by two perpendicularly staggered bamboo nails 7.

[0040] Specific size:

[0041] Domestic fast-growing poplar board material: cross-sectional size 40mm×120mm, spliced ​​by plywood of varying lengths to the set size.

[0042] Bamboo plywood: length 3200mm, width 3200mm, thickness 40mm.

[0043] Bamboo nail: diameter 6.0mm, length 80mm.

[0044] The above describes the embodiments of the present invention in detail with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions, and variations of these embodiments within the scope of the principles and technical concepts of the present invention are still within the scope of protection of the present invention.

Claims

1. A hybrid cross-laminated timber connected by bamboo nails, characterized in that: The total number of layers of the hybrid orthogonal glued timber is an odd number of 3 or more, wherein the layer boards of the odd-numbered hybrid orthogonal glued timber layers are composed of multiple discrete layer boards, and the layer boards of the even-numbered hybrid orthogonal glued timber layers are integral layer boards, and the upper and lower adjacent layer boards are laid perpendicular to each other and connected with bamboo nails.

2. The hybrid cross-laminated timber connected by bamboo nails according to claim 1, characterized in that: The discrete layer boards are formed by laying standard materials or boards side by side, and the integral layer boards are glued solid wood boards, plywood, veneer laminates, oriented wood boards or bamboo plywood.

3. The hybrid cross-laminated timber connected by bamboo nails according to claim 2, characterized in that: The minimum width of the discrete layer is 50 mm, and the minimum thickness is 12 mm; the maximum width is 150 mm, and the maximum thickness is 45 mm; the minimum thickness of the integral layer is 12 mm, and the maximum thickness is 45 mm.

4. The hybrid cross-laminated timber connected by bamboo nails according to claim 3, characterized in that: The moisture content of the discrete layer plates and the integral layer plates should not be greater than 15%, and the difference in moisture content between adjacent layer plates should not be greater than 5%.

5. The hybrid cross-laminated timber connected by bamboo nails according to claim 4, characterized in that: The bamboo nail is a compacted nail, one end of which is a cone and the other end of which is a round head without a protruding head.

6. The hybrid cross-laminated timber connected by bamboo nails according to claim 5, characterized in that: The diameter of the bamboo nail is in the range of 2.5mm to 7.5mm, and the length is in the range of 25mm to 90mm.

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