Arc-shaped recombined bamboo-wood composite material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of arc-shaped recombined bamboo-wood composite materials, in particular to an arc-shaped recombined bamboo-wood composite material and a preparation method and application thereof. The preparation method provided by the invention comprises the following steps: carrying out gum dipping treatment on a bamboo bundle veneer in a phenolic glue solution to obtain a gum-dipped bamboo bundle veneer; the curve direction of the arc-shaped bottom plate is stipulated as a rift grain direction, and the linear direction is stipulated as a cross grain direction; and after the impregnated bamboo bundle veneers are laminated and paved on an arc-shaped bottom plate, compression molding is carried out, and the arc-shaped recombined bamboo-wood composite material is obtained. The rift grain direction of the glue-dipped bamboo bundle veneers is consistent with the rift grain direction of the arc-shaped bottom plate; a tough material layer is added between every two adjacent layers in the process of laminating and paving. The arc-shaped recombined bamboo-wood composite material prepared by the preparation method disclosed by the invention has excellent obdurability and dimensional stability.

Description

Technical Field

[0001] The present invention relates to the technical field of arc-shaped recombined bamboo-wood composite materials, and particularly relates to an arc-shaped recombined bamboo-wood composite material, a preparation method thereof and an application thereof. Background Art

[0002] Traditional arc-shaped wood materials lack sufficient strength and toughness. When the convex surface is impacted, it is easy to cause the concave surface to bear tensile force, resulting in irreversible damage. The main raw material of recombined wood is bamboo bundles, which have high longitudinal strength and can withstand large impact damages. However, the lateral strength of all-bamboo bundle products is insufficient and they are prone to splitting. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide an arc-shaped recombined bamboo-wood composite material, a preparation method thereof and an application thereof. The arc-shaped recombined bamboo-wood composite material prepared by the preparation method of the present invention has excellent strength and toughness and dimensional stability.

[0004] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0005] The present invention provides a preparation method of an arc-shaped recombined bamboo-wood composite material, comprising the following steps:

[0006] Soaking bamboo bundle veneers in phenolic resin adhesive solution to obtain soaked bamboo bundle veneers;

[0007] Specify the curve direction of the arc-shaped bottom plate as the grain direction and the straight line direction as the cross-grain direction; after laminating and paving the soaked bamboo bundle veneers on the arc-shaped bottom plate, press and mold to obtain the arc-shaped recombined bamboo-wood composite material; the grain direction of the soaked bamboo bundle veneers is consistent with the grain direction of the arc-shaped bottom plate;

[0008] A toughness material layer is added between adjacent layers during the laminating and paving process.

[0009] Preferably, the phenolic resin adhesive solution comprises phenolic resin adhesive and montmorillonite; the solid content of the phenolic resin adhesive is 20wt%;

[0010] The mass ratio of phenolic resin and montmorillonite in the phenolic resin adhesive is 100:(0-50).

[0011] Preferably, the temperature of the soaking treatment is 5-30°C and the time is 10-20 min.

[0012] Preferably, after the soaking treatment, drying is also included, and the moisture content of the obtained soaked bamboo bundle veneers after drying is 10-15%.

[0013] Preferably, the toughness material in the toughness material layer comprises fiberglass cloth and / or wood veneer.

[0014] Preferably, when the toughening material is a single layer of wood veneer, the wood veneer is laid along the transverse grain direction;

[0015] When the number of layers of wood veneer in the toughening material is greater than 1 layer, the wood veneer is laid in a staggered manner.

[0016] Preferably, the pressing and forming includes hot pressing and forming.

[0017] Preferably, the process of hot pressing and forming is to perform hot pressing at a temperature of 140 - 150 °C and a pressure of 15 - 25 MPa at a speed of 0.8 - 1.5 min / mm, and then, under the condition of maintaining the original pressure, introduce cooling water for 15 - 25 min.

[0018] The present invention also provides an arc-shaped recombined bamboo-wood composite material prepared by the preparation method described in the above technical solution.

[0019] The present invention also provides the application of the arc-shaped recombined bamboo-wood composite material described in the above technical solution in traffic guardrails and beam load-bearing members.

[0020] The present invention provides a preparation method for an arc-shaped recombined bamboo-wood composite material, comprising the following steps: impregnating bamboo bundle veneers in phenolic adhesive solution to obtain impregnated bamboo bundle veneers; defining the curved direction of the arc-shaped bottom plate as the longitudinal grain direction and the straight direction as the transverse grain direction; laminating and laying the impregnated bamboo bundle veneers on the arc-shaped bottom plate and then performing pressing and forming to obtain the arc-shaped recombined bamboo-wood composite material; the longitudinal grain direction of the impregnated bamboo bundle veneers is consistent with the longitudinal grain direction of the arc-shaped bottom plate; a toughening material layer is added between adjacent layers during the laminating and laying process. The preparation method of the present invention uses bamboo bundle veneers as the core layer to provide sufficient mechanical strength, and adding a toughening material during the laminating and laying process can play a role in tensile resistance when impacted. The entire preparation process adopts a pressing and forming process to make the arc-shaped structure of the prepared arc-shaped recombined bamboo-wood composite material more complete; according to the records of the embodiments, the water absorption thickness swelling rate of the arc-shaped recombined bamboo-wood composite material prepared by the preparation method of the present invention is less than 5%, the water absorption width swelling rate is less than 3%, the bending strength is 120 - 180 MPa, and the impact toughness is 40 - 70 J / mm 2 ; the transverse strength is above 30 MPa. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic diagram of the laminating and laying described in the present invention;

[0022] Figure 2 is a schematic diagram of cutting the arc-shaped recombined bamboo-wood composite material described in the present invention into long strip arc shapes;

[0023] Figure 3It is a schematic diagram of assembling the arc-shaped reconstituted bamboo-wood composite material of the present invention into an arc-shaped double-piece component. DETAILED DESCRIPTION

[0024] The present invention provides a method for preparing an arc-shaped reconstituted bamboo-wood composite material, comprising the following steps:

[0025] The bamboo bundle veneer is dipped in phenolic glue to obtain the dipped bamboo bundle veneer;

[0026] The curved direction of the arc bottom plate is specified as the along-grain direction, and the straight direction is specified as the transverse-grain direction; the impregnated bamboo bundle veneer is layered and laid on the arc bottom plate, and then pressed and formed to obtain the arc-shaped reconstituted bamboo-wood composite material; the along-grain direction of the impregnated bamboo bundle veneer is consistent with the along-grain direction of the arc bottom plate;

[0027] During the layer-by-layer paving process, a tough material layer is added between two adjacent layers.

[0028] In the present invention, unless otherwise specified, all preparation raw materials are commercially available products well known to those skilled in the art.

[0029] The invention performs a gum-impregnated treatment on the bamboo bundle veneer in a phenolic glue solution to obtain the gum-impregnated bamboo bundle veneer.

[0030] In the present invention, the bamboo bundle veneer is preferably obtained by transversely weaving bamboo bundles. Before the transverse weaving, the present invention preferably pre-treats the bamboo bundles, and the pre-treatment preferably includes using a sander or a slicer to remove the green and yellow fibers of the bamboo bundles, and then using a deflaking machine to deflake the bamboo bundles to obtain bamboo bundles with unbroken longitudinal fibers and loose and staggered transverse fibers. In an embodiment of the present invention, the deflaking is performed by 12 deflaking wheel groups.

[0031] The present invention has no special limitation on the process of transverse weaving, and it can be carried out by a process well known to those skilled in the art. In an embodiment of the present invention, the size of the bamboo bundle veneer obtained after the transverse weaving can be 2400mm×1200mm.

[0032] After the transverse weaving is completed, the present invention preferably further comprises drying. In the present invention, the drying method is preferably drying, and the present invention has no special limitation on the drying process. The process well known to those skilled in the art is adopted and the moisture content of the bamboo bundle veneer after drying is controlled within the range of 10-15%.

[0033] In the present invention, the phenolic glue solution preferably includes phenolic glue and montmorillonite. The preparation method of the phenolic glue solution includes mixing the phenolic glue and montmorillonite to obtain the phenolic glue solution.

[0034] In the present invention, the phenolic adhesive is preferably a conventional commercially available phenolic resin adhesive for recombined bamboo. In the present invention, the solid content of the phenolic adhesive is preferably 20 wt%.

[0035] In the present invention, the mass ratio of phenolic resin to montmorillonite in the phenolic adhesive is preferably 100:(0 - 50), more preferably 100:(10 - 40). In the examples of the present invention, the mass ratio of the solid mass in the phenolic adhesive to the mass of montmorillonite can be 100:10, 100:30 or 100:50.

[0036] The present invention has no special limitation on the mixing process. A process well-known to those skilled in the art can be adopted as long as the montmorillonite is evenly dispersed in the phenolic adhesive.

[0037] In the present invention, the temperature of the impregnation treatment is preferably 5 - 30 °C (room temperature); the time of the impregnation treatment is preferably 10 - 20 min, more preferably 15 min. In the examples of the present invention, the temperature of the impregnation treatment is room temperature and the time is 15 min. In the examples of the present invention, the impregnation treatment is to place the dried bamboo bundle veneer in an impregnation tank containing the phenolic adhesive solution for impregnation treatment.

[0038] In the present invention, when montmorillonite is added to the phenolic adhesive solution during the impregnation treatment, the layered structure of montmorillonite can absorb energy and dissipate energy when subjected to energy impact. Therefore, using montmorillonite to modify the bamboo bundle can endow the arc-shaped recombined bamboo-wood composite with the ability to absorb energy and resist deformation. At the same time, the high specific surface area and developed pore structure of the bamboo bundle can also provide a good environment for the deposition of montmorillonite.

[0039] After the impregnation treatment is completed, the present invention preferably further includes drying. In the present invention, the drying method is preferably drying by baking. The present invention has no special limitation on the baking process. A process well-known to those skilled in the art can be adopted as long as the moisture content of the impregnated bamboo bundle veneer after drying is controlled within the range of 10 - 15%.

[0040] After obtaining the impregnated bamboo bundle veneer, in the present invention, with the curve direction of the arc-shaped bottom plate as the longitudinal direction and the straight line direction of the arc-shaped bottom plate as the transverse direction, the bamboo bundle arrangement direction of the impregnated bamboo bundle veneer is laminated and paved in the longitudinal direction (as Figure 1 shown), and then pressed into shape to obtain the arc-shaped recombined bamboo-wood composite; a layer of ductile material is added between adjacent layers during the lamination and paving process.

[0041] In the present invention, the radian of the arc-shaped bottom plate is preferably 0 to 1.0 rad. In the embodiments of the present invention, the radian of the arc-shaped bottom plate can be 0.25 rad, 0.5 rad or 1.0 rad.

[0042] The present invention has no special requirements for the material of the arc-shaped bottom plate, and an arc-shaped bottom plate made of a suitable material can be selected according to actual needs.

[0043] The present invention has no special limitation on the number of layers of the laminated paving. Laminated paving can be carried out according to the required use thickness. In the embodiments of the present invention, the number of layers of the laminated paving is 9 layers, 14 layers or 16 layers.

[0044] In the present invention, a toughness material layer is added between adjacent layers during the laminated paving process. In the present invention, the adjacent layers can be understood as between adjacent bamboo bundle veneer layers after impregnation and bamboo bundle veneer layers after impregnation treatment, or between adjacent bamboo bundle veneer layers after impregnation and the toughness material layer, or between adjacent toughness material layers and bamboo bundle veneer layers after impregnation, or between adjacent toughness material layers. The present invention has no special limitation on the number of layers of the added toughness material layer.

[0045] In the present invention, the toughness material in the toughness material layer preferably includes fiberglass cloth and / or wood veneer, more preferably includes fiberglass cloth or wood veneer; when the toughness material is 1 layer of wood veneer, the wood veneer is preferably paved along the transverse grain direction; when the number of layers of wood veneer in the toughness material is greater than 1 layer, the wood veneer is preferably paved in a staggered manner. In the present invention, the material of the wood veneer is preferably eucalyptus veneer, birch veneer, fir veneer or poplar veneer. In the embodiments of the present invention, the material of the wood veneer can be poplar veneer, birch veneer, eucalyptus veneer.

[0046] In the present invention, the laminated paving method can achieve bending along the length direction and enhance the impact resistance; the main reason is that: when the arc-shaped structure is impacted, its geometric shape can disperse the impact force over a larger area instead of concentrating on a certain point. This dispersion effect helps to reduce the limitation of local stress concentration, thereby improving the overall impact resistance of the material. In contrast, when a flat material is impacted, the stress is more likely to concentrate near the impact point, resulting in too high local stress and thus more likely to be damaged.

[0047] In the present invention, bamboo bundles are selected as the main material for laminated paving. Bamboo bundles are materials with extremely significant orthotropic properties, and their tensile strength in the longitudinal direction is much higher than that in the transverse direction. Laminating and paving the bamboo bundles in the longitudinal direction of the bamboo bundles after dipping in glue can make full use of the longitudinal tensile strength of the bamboo bundles; at the same time, adding fiberglass cloth can play a role in further strengthening; adding wood veneer can play a role in absorbing energy. Therefore, adding a toughening material during the laminated paving process and locating it on the concave surface of the arc structure can further enhance the tensile resistance of the concave surface when the convex surface of the arc structure is impacted, and at the same time enhance the transverse strength of the arc-reconstituted bamboo-wood composite. In the present invention, using wood veneer as the surface panel can provide the functions of transverse strengthening and surface decoration for the arc-reconstituted bamboo-wood composite.

[0048] In the present invention, the pressing and forming preferably includes hot pressing and forming. The process of hot pressing and forming is preferably carried out at a temperature of 140-150 °C and a pressure of 19 MPa at a speed of 1 min / mm for hot pressing, and then cooling water is introduced for 20 min under the condition of maintaining the original pressure. In the embodiments of the present invention, the process of hot pressing and forming can be carried out at a temperature of 145 °C and a pressure of 19 MPa at a speed of 1 min / mm for hot pressing, and then cooling water is introduced for 20 min under the condition of maintaining the original pressure. In the present invention, the hot pressing and forming is preferably carried out in a hot press corresponding to the arc.

[0049] After the pressing and forming, the present invention preferably further includes unloading the plate, cutting, and assembling in sequence. In the present invention, the unloading of the plate is preferably stacking the arc-reconstituted bamboo-wood composite obtained by the pressing and forming on the arc plate until the equilibrium moisture content is reached. The present invention has no special limitations on the processes of cutting and assembling, and the processes well-known to those skilled in the art are used for cutting and assembling. For example, the cutting can be cutting the obtained arc-reconstituted bamboo-wood composite into long strip arc shapes (as Figure 2 shown); the assembling can be assembling the obtained arc-reconstituted bamboo-wood composite into an arc double-pin component (as Figure 3 shown).

[0050] The present invention also provides an arc-reconstituted bamboo-wood composite prepared by the preparation method described in the above technical solution.

[0051] In the present invention, the radian of the arc-reconstituted bamboo-wood composite is preferably 0-1.0 rad. In the embodiments of the present invention, the radian of the arc-reconstituted bamboo-wood composite can be 0.25 rad, 0.5 rad, or 1.0 rad.

[0052] In an embodiment of the present invention, the arc-shaped reconstituted bamboo-wood composite material includes an arc-shaped bottom plate and a laminated paving layer located on the concave surface of the arc-shaped bottom plate. The laminated paving layer may be a first wood veneer parallel grain paving layer, a first wood veneer cross grain paving layer, a first bamboo bundle veneer parallel grain paving layer, a second bamboo bundle veneer parallel grain paving layer, a third bamboo bundle veneer parallel grain paving layer, a fourth bamboo bundle veneer parallel grain paving layer, a fiberglass cloth layer, a second wood veneer parallel grain paving layer, and a second wood veneer cross grain paving layer arranged in layers in sequence; or a first single wood board parallel grain paving layer, a first single wood board cross grain paving layer, a second single wood board parallel grain paving layer, a first bamboo bundle veneer parallel grain paving layer, a second bamboo bundle veneer parallel grain paving layer, a third bamboo bundle veneer parallel grain paving layer, a fourth bamboo bundle veneer parallel grain paving layer, a fifth bamboo bundle veneer parallel grain paving layer, a sixth bamboo bundle veneer parallel grain paving layer, a first fiberglass cloth layer, a second fiberglass cloth layer, a third single wood board parallel grain paving layer, a second single wood board cross grain paving layer, and a fourth single wood board parallel grain paving layer arranged in layers in sequence; or a first wood veneer parallel grain paving layer, a first bamboo bundle veneer parallel grain paving layer, a second bamboo bundle veneer parallel grain paving layer, a fiberglass cloth layer, and a second wood veneer parallel grain paving layer.

[0053] The present invention also provides the application of the arc-shaped reconstituted bamboo-wood composite material described in the above technical solution in traffic guardrails and beam load-bearing members. The present invention does not have any special limitations on the application method, and the method well-known to those skilled in the art can be adopted.

[0054] Next, the technical solutions in the present invention will be clearly and completely described in conjunction with the embodiments in the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0055] Embodiment 1

[0056] After the bamboo bundles are subjected to de-greening and de-yellowing treatment, they are subjected to brooming and delamination through 12 sets of delamination wheel groups to obtain pre-treated bamboo bundles;

[0057] The bamboo bundles are transversely woven by a knitting machine to obtain bamboo bundle veneers with a size of 2400 mm × 1200 mm (length × width);

[0058] After the bamboo bundle veneers are dried to a moisture content within the range of 10-15%, they are impregnated with phenolic resin glue (solid content: 20 wt%) (temperature: normal temperature, time: 15 min), and then dried to obtain impregnated bamboo bundle veneers (with a moisture content within the range of 10-15%);

[0059] Taking the curve direction of the arc-shaped bottom plate as the longitudinal direction and the straight line direction of the arc-shaped bottom plate as the transverse direction, perform laminated paving on the concave surface of the arc-shaped bottom plate (with a radian of 0.25 rad). From bottom to top, there are successively the longitudinal paving layer of the first wood veneer (made of poplar veneer), the transverse paving layer of the first wood veneer (made of poplar veneer), the longitudinal paving layer of the first bamboo bundle veneer, the longitudinal paving layer of the second bamboo bundle veneer, the longitudinal paving layer of the third bamboo bundle veneer, the longitudinal paving layer of the fourth bamboo bundle veneer, the fiberglass cloth layer, the longitudinal paving layer of the second wood veneer (made of poplar veneer), and the transverse paving layer of the second wood veneer (made of poplar veneer). Then send it to an arc-shaped hot press with the corresponding radian for hot pressing (under the conditions of a temperature of 145 °C and a pressure of 19 MPa, hot press at a speed of 1 min / mm, and then introduce cooling water for 20 min while maintaining the original pressure). Stack the obtained arc-shaped reconstituted bamboo-wood composite on the arc-shaped plate until the equilibrium moisture content, and then perform cutting and assembly successively according to the usage requirements to obtain the arc-shaped reconstituted bamboo-wood composite (with a thickness of 12 mm and a radian of 0.25 rad).

[0060] Example 2

[0061] After the bamboo bundles are subjected to de-greening and de-yellowing treatment, they are subjected to brooming and delamination through 12 sets of delamination wheels to obtain pretreated bamboo bundles;

[0062] Use a knitting machine to perform transverse knitting on the bamboo bundles to obtain a bamboo bundle veneer with a size of 2400 mm × 1200 mm (length × width);

[0063] Mix phenolic resin adhesive (solid content of 20%) and montmorillonite according to a mass ratio of 100:10 to obtain a phenolic resin adhesive solution;

[0064] After drying the bamboo bundle veneer to a moisture content within the range of 10 - 15%, perform impregnation treatment in the phenolic resin adhesive solution (at room temperature for 15 min), and then dry it to obtain the impregnated bamboo bundle veneer (with a moisture content within the range of 10 - 15%);

[0065] Taking the curve direction of the arc-shaped bottom plate as the longitudinal direction and the straight line direction of the arc-shaped bottom plate as the transverse direction, perform laminated paving on the concave surface of the arc-shaped bottom plate (with a radian of 0.25 rad). From bottom to top, they are the longitudinal paving layer of the first wood veneer (made of birch veneer), the transverse paving layer of the first wood veneer (made of birch veneer), the longitudinal paving layer of the first bamboo bundle veneer, the longitudinal paving layer of the second bamboo bundle veneer, the longitudinal paving layer of the third bamboo bundle veneer, the longitudinal paving layer of the fourth bamboo bundle veneer, the fiberglass cloth layer, the longitudinal paving layer of the second wood veneer (made of birch veneer), and the transverse paving layer of the second wood veneer (made of birch veneer). Then send it to an arc-shaped hot press with the corresponding radian for hot pressing (after hot pressing at a temperature of 145 °C and a pressure of 19 MPa at a speed of 1 min / mm, cool water is introduced for 20 min while maintaining the original pressure). Stack the obtained arc-shaped recombined bamboo and wood composite materials on the arc-shaped plate until the equilibrium moisture content, and then perform cutting and assembly in sequence according to the usage requirements to obtain the arc-shaped recombined bamboo and wood composite material (with a thickness of 12 mm and a radian of 0.25 rad).

[0066] Example 3

[0067] After the bamboo bundles are subjected to de-greening and de-yellowing treatment, they are subjected to brooming and delamination through 12 sets of delamination wheels to obtain pre-treated bamboo bundles;

[0068] Use a knitting machine to horizontally knit the bamboo bundles to obtain a bamboo bundle veneer with a size of 2400 mm × 1200 mm (length × width);

[0069] Mix phenolic resin adhesive (with a solid content of 20%) and montmorillonite according to a mass ratio of 100:10 to obtain a phenolic resin adhesive solution;

[0070] After drying the bamboo bundle veneer to a moisture content within the range of 10 - 15%, perform impregnation treatment in the phenolic resin adhesive solution (at room temperature for 15 min), and then dry it to obtain the impregnated bamboo bundle veneer (with a moisture content within the range of 10 - 15%);

[0071] Taking the curve direction of the arc-shaped bottom plate as the longitudinal direction and the straight line direction of the arc-shaped bottom plate as the transverse direction, perform laminated paving on the concave surface of the arc-shaped bottom plate (with a radian of 0.25 rad). From bottom to top, they are the longitudinal paving layer of the first wood veneer (made of eucalyptus veneer), the transverse paving layer of the first wood veneer (made of eucalyptus veneer), the longitudinal paving layer of the first bamboo bundle veneer, the longitudinal paving layer of the second bamboo bundle veneer, the longitudinal paving layer of the third bamboo bundle veneer, the longitudinal paving layer of the fourth bamboo bundle veneer, the fiberglass cloth layer, the longitudinal paving layer of the second wood veneer (made of eucalyptus veneer), and the transverse paving layer of the second wood veneer (made of eucalyptus veneer). Then send it to an arc-shaped hot press with the corresponding radian for cold pressing (after hot pressing at a temperature of 145 °C and a pressure of 19 MPa at a speed of 1 min / mm, cool water is introduced for 20 min while maintaining the original pressure). Stack the obtained arc-shaped reconstituted bamboo-wood composite material on the arc-shaped plate until the equilibrium moisture content, and then perform cutting and assembly in sequence according to the usage requirements to obtain the arc-shaped reconstituted bamboo-wood composite material (with a thickness of 12 mm and a radian of 0.25 rad).

[0072] Example 4

[0073] After the bamboo bundles are subjected to the treatment of removing green and yellow, they are subjected to brooming and defibering through 12 sets of defibering wheels to obtain the pretreated bamboo bundles;

[0074] Use a knitting machine to perform transverse knitting on the bamboo bundles to obtain a bamboo bundle veneer of 2400 mm × 1200 mm (length × width);

[0075] According to the mass ratio of 100:30, mix phenolic resin adhesive (solid content of 20%) and montmorillonite to obtain a phenolic resin adhesive solution;

[0076] After drying the bamboo bundle veneer to a moisture content within the range of 10 - 15%, perform dipping treatment in the phenolic resin adhesive solution (at room temperature for 15 min), and then dry it to obtain the dipped bamboo bundle veneer (with a moisture content within the range of 10 - 15%);

[0077] Taking the curve direction of the arc-shaped bottom plate as the longitudinal grain direction and the straight line direction of the arc-shaped bottom plate as the transverse grain direction, perform laminated paving on the concave surface of the arc-shaped bottom plate (with a radian of 0.5 rad). From bottom to top, they are the first single wood board (made of poplar veneer) longitudinal paving layer, the first single wood board (made of poplar veneer) transverse paving layer, the second single wood board (made of poplar veneer) longitudinal paving layer, the first bamboo bundle veneer longitudinal paving layer, the second bamboo bundle veneer longitudinal paving layer, the third bamboo bundle veneer longitudinal paving layer, the fourth bamboo bundle veneer longitudinal paving layer, the fifth bamboo bundle veneer longitudinal paving layer, the sixth bamboo bundle veneer longitudinal paving layer, the first fiberglass cloth layer, the second fiberglass cloth layer, the third single wood board (made of poplar veneer) longitudinal paving layer, the second single wood board (made of poplar veneer) transverse paving layer, and the fourth single wood board (made of poplar veneer) longitudinal paving layer transverse paving layer. Then send it to an arc-shaped hot press with the corresponding radian for hot pressing (after hot pressing at a speed of 1 min / mm under the conditions of a temperature of 145 °C and a pressure of 19 MPa, introduce cooling water for 20 min while maintaining the original pressure). Stack the obtained arc-shaped reconstituted bamboo-wood composite material on the arc-shaped board until the equilibrium moisture content, and then perform cutting and assembly in sequence according to the usage requirements to obtain the arc-shaped reconstituted bamboo-wood composite material (with a thickness of 18 mm and a radian of 0.5 rad).

[0078] Example 5

[0079] After the bamboo bundles are subjected to debarking and degumming treatment, they are broomized and delaminated through 12 sets of defibration wheels to obtain pretreated bamboo bundles;

[0080] Use a knitting machine to perform transverse knitting on the bamboo bundles to obtain bamboo bundle veneers with a size of 2400 mm × 1200 mm (length × width);

[0081] According to a mass ratio of 100:50, mix phenolic resin glue (with a solid content of 20%) and montmorillonite to obtain a phenolic resin glue solution;

[0082] After drying the bamboo bundle veneers to a moisture content within the range of 10 - 15%, perform dipping treatment in the phenolic resin glue solution (at room temperature for 15 min), and then dry to obtain dipped bamboo bundle veneers (with a moisture content within the range of 10 - 15%);

[0083] Taking the curve direction of the arc-shaped bottom plate as the longitudinal direction and the straight line direction of the arc-shaped bottom plate as the transverse direction, laminated paving is carried out on the concave surface of the arc-shaped bottom plate (with a radian of 1.0 rad). From bottom to top, there are a first wood veneer (made of poplar veneer) longitudinal paving layer, a first bamboo bundle veneer longitudinal paving layer, a second bamboo bundle veneer longitudinal paving layer, a fiberglass cloth layer, and a second wood veneer (made of poplar veneer) longitudinal paving layer. Then it is sent to an arc-shaped hot press with a corresponding radian for hot pressing (after hot pressing at a speed of 1 min / mm under the conditions of a temperature of 145 °C and a pressure of 19 MPa, cooling water is introduced for 20 min while maintaining the original pressure). The obtained arc-shaped reconstituted bamboo-wood composite is stacked on the arc-shaped plate until the equilibrium moisture content, and then cut and assembled successively according to the usage requirements to obtain the arc-shaped reconstituted bamboo-wood composite (with a thickness of 6 mm and a radian of 1.0 rad).

[0084] The performance parameters of the arc-shaped reconstituted bamboo-wood composite described in Examples 1 to 5 are shown in Table 1:

[0085] Table 1 Performance parameters of the arc-shaped reconstituted bamboo-wood composite described in Examples 1 to 5

[0086]

[0087]

[0088] The above is only the preferred embodiment of the present invention and does not impose any form of limitation on the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for preparing an arc-shaped reconstituted bamboo-wood composite material, characterized in that: The following steps are involved: The bamboo bundle veneer is dipped in phenolic glue to obtain the dipped bamboo bundle veneer; The curved direction of the arc bottom plate is specified as the along-grain direction, and the straight direction is specified as the transverse-grain direction; the impregnated bamboo bundle veneer is layered and laid on the arc bottom plate, and then pressed and formed to obtain the arc-shaped reconstituted bamboo-wood composite material; the along-grain direction of the impregnated bamboo bundle veneer is consistent with the along-grain direction of the arc bottom plate; During the layer-by-layer paving process, a tough material layer is added between two adjacent layers.

2. The preparation method according to claim 1, characterized in that The phenolic glue solution comprises phenolic glue and montmorillonite; the solid content of the phenolic glue is 20wt%; The mass ratio of the phenolic resin to the montmorillonite in the phenolic glue is 100:(0-50).

3. The preparation method according to claim 1, characterized in that: The temperature of the dipping treatment is 5 to 30° C., and the time is 10 to 20 minutes.

4. The preparation method according to claim 3, characterized in that: After the dipping treatment is completed, the process further includes drying. The moisture content of the dipping bamboo bundle veneer obtained after drying is 10-15%.

5. The preparation method according to claim 1, characterized in that: The tough material in the tough material layer includes glass fiber cloth and / or wood veneer.

6. The preparation method according to claim 5, characterized in that: When the tough material is a single layer of wood veneer, the wood veneer is laid along the transverse direction of the grain; When the number of layers of the wood veneers in the tough material is greater than one, the wood veneers are laid in a staggered manner.

7. The preparation method according to claim 1, characterized in that: The compression molding includes hot compression molding.

8. The preparation method according to claim 7, characterized in that: The hot pressing process is to perform hot pressing at a temperature of 140 to 150° C. and a pressure of 15 to 25 MPa at a speed of 0.8 to 1.5 min / mm, and then introduce cooling water for 15 to 25 min while maintaining the original pressure.

9. The arc-shaped reconstituted bamboo-wood composite material prepared by the preparation method according to any one of claims 1 to 8.

10. Application of the arc-shaped reconstituted bamboo-wood composite material according to claim 9 in traffic guardrails and beam load-bearing components.

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