CN108748594A - Local reinforced shaving board based on stress distribution, preparation method thereof and covered shear wall - Google Patents

Abstract

The invention discloses a locally reinforced particle board based on stress distribution, a preparation method thereof and a cladding shear wall, belonging to the field of particle board shear walls. The particle board includes a reinforced area and a non-reinforced area, the reinforced area is arranged on both sides of the non-reinforced area, and the density of the reinforced area is greater than that of the non-reinforced area. In the preparation method of the particle board, in the paving process, shavings are added on both sides of the paving slab to form a reinforced area, and a non-reinforced area is formed at the slab without the added shavings. The cladding shear wall includes the particleboard prepared by the above process, and the particleboard and the wall frame are installed and combined. The present invention significantly improves the strength and stress bearing capacity of the particle board by increasing the density on both sides of the particle board, fully exerts the performance of the board, and solves the problem of uneven stress distribution and premature yield of the conventional cladding board under the action of horizontal load, thereby improving the wood-based structure. The lateral resistance performance of the plate shear wall is reasonable in design and strong in operability.

Description

Locally reinforced particleboard based on stress distribution and its preparation method and shearing of cladding force wall

technical field

The invention belongs to the field of particle board shear walls, and in particular relates to a locally reinforced particle board based on stress distribution, a preparation method thereof and a cladding shear wall.

Background technique

In buildings with particleboard shear walls, the shear walls consist of particleboard and gauge lumber connected by nails, and mainly bear the horizontal forces generated by earthquake action or wind load. When the horizontal shear force is large, the cladding panels of conventional particleboard shear walls are prone to misalignment and deformation along the joints, and damage phenomena at the joints such as nail shearing and pulling out occur, resulting in the cladding panels and stud columns Separated, the wall structure fails and loses its bearing capacity. Therefore, conventional particleboard shear walls need to further improve lateral force resistance, ductility and stiffness, among which the shear resistance of cladding panels plays a decisive role.

When the entire wall is subjected to lateral horizontal loads, the cladding panels nailed to the frame and stud columns provide lateral support for the stud columns and are also constrained by the stud columns to work together. in a state of plane shear stress. With the inclination of the stud column, the restraint of the panel nail by the wood fiber around the nail connecting the stud column and the cladding panel is weakened, and shear slip occurs at the nail joint at the corner. As the horizontal load gradually increases, the shear force on the panel nails around the cladding panels gradually increases, and the shear slip of the nails also gradually increases. Each cladding panel rotates around its own central axis, but at the center of the panel The stress of the panel is much smaller than the stress at the corner. When the panel at the edge is damaged, the panel at the center has almost no damage, and its strength cannot be fully exerted.

At present, the conventional particleboard shear wall increases the strength of the wall by improving the structural structure, but ignores further research and utilization of cladding panels.

Contents of the invention

1. Problems to be solved

Aiming at the problem of local early failure at corners and other parts caused by uneven stress on cladding panels in existing shear walls, the invention provides a locally reinforced particleboard based on stress distribution, a preparation method thereof, and a cladding shear wall. Based on the relationship between particleboard density and strength, the cladding panel of the present invention adopts a method of locally enhancing the panel density to improve the mechanical properties of easily damaged parts such as the corners of the panel, fully exert the performance of the panel, and improve the overall performance of the particleboard shear wall. Anti-lateral strength to ensure the overall strength of the structure.

2. Technical solution

In order to solve the above problems, the present invention adopts the following technical solutions.

Locally reinforced particleboard based on stress distribution, the particleboard includes a reinforced area and a non-reinforced area in the horizontal direction perpendicular to the thickness, the reinforced area is arranged on both sides of the non-reinforced area, and the reinforced The density of the regions is greater than that of said non-enhancing regions, the density of the non-enhancing regions increasing progressively towards the enhancing regions.

Preferably, the density of the enhanced area is 1.1-1.7 times that of the non-enhanced area.

Preferably, the enhanced area and the non-enhanced area have the same thickness.

The preparation method of the locally reinforced particleboard based on the stress distribution includes adding shavings to both sides of the paving slab in the paving process to form a reinforced area, and forming a non-reinforced area at the slab without adding the shavings.

Preferably, the width of the reinforced area is 1/8-1/7 of the width of the slab.

Preferably, the increased thickness of the shavings in the reinforced area gradually increases toward the outside along the non-reinforced area.

Preferably, the included angle between the inclined plane of progressive thickness of the shavings in the reinforced area and the plane where the non-reinforced area is located is 20°-40°.

Preferably, the shaving preparation process and the glue mixing process are also included before the paving process, and the slab is pre-pressed, hot-pressed and post-treated after the paving process.

Preferably, in the pre-pressing and hot-pressing processes, the same treatment method is used for the reinforced area and the non-reinforced area.

The cladding shear wall includes the particleboard prepared by the above method, and the particleboard and the wall frame are installed and combined.

3. Beneficial effects

Compared with the prior art, the beneficial effects of the present invention are:

(1) The present invention is based on the relationship between the density, strength and withstand stress in the material of particleboard, considering from the material performance level, in the preparation method of particleboard, the increase of shavings is carried out on both sides of the particleboard slab. After hot pressing, an invisible high-density reinforcement belt is formed on both sides of the particleboard, which greatly improves the stress that the four corners of the particleboard can bear; and the shear wall made of this kind of particleboard, even if the wall is subjected to horizontal lateral force damage, the two sides of the particleboard will not yield prematurely due to the large stress at the four-corner joints, and the strength of the wall is significantly improved; if the high-density area and the normal-density area are set in the vertical direction of the thickness of the particleboard, the above-mentioned problems still cannot be solved. Stress issues;

(2) The present invention considers from the point of view of the material mechanics of the board, and enhances the overall mechanical properties of the shear wall by increasing the density of the board at the vulnerable part of the edge of the particle board, which fills the gap in material reinforcement in the existing shear wall reinforcement technology , on the basis of the original board, make full use of the material properties and improve the overall strength of the wall;

(3) A kind of locally reinforced particle board based on stress distribution of the present invention, the density of its reinforced area is 1.1～1.7 times of the non-reinforced area, so that the particle board achieves local reinforcement while saving materials;

(4) The preparation method of the locally reinforced particleboard based on stress distribution of the present invention, wherein in the paving process, the width of the reinforced area is 1/8 to 1/7 of the width of the slab, and the reinforced width is too small to achieve reinforced Requirements, if the reinforcement width is increased, the proportion of the effective reinforcement range is small, and the effective utilization of materials cannot be achieved;

(5) The preparation method of the locally reinforced particleboard based on stress distribution of the present invention, when paving, the thickness of the shavings in the reinforced area is gradually increased along the non-reinforced area to the outside, so that the junction of the enhanced area and the non-enhanced area is smoothly transitioned, and the density Gradually increase to avoid stress concentration at the sudden change in density of the particleboard after pressing; during the paving process, ensure that the angle between the progressive slope of the particle thickness in the reinforced area and the plane of the non-reinforced area is 20° to 40° , it can solve the problem of stress concentration, the design is reasonable, and the material is saved;

(6) The preparation method of the locally reinforced particle board based on stress distribution of the present invention also includes a particle preparation process and a glue mixing process before the paving process, and pre-presses, hot-presses and post-treats the slab after the paving process; In the pre-pressing and hot-pressing process, the reinforced area and the non-reinforced area adopt the same treatment process to ensure the flatness of the plate and strong operability;

(7) The cladding shear wall of the present invention adopts partially reinforced particle board and wall skeleton to be installed and combined, which is more convenient for disassembly and assembly, and the assembly degree is higher, and the partially reinforced particle board makes the overall strength of the wall body remarkable Improvement, which effectively solves the problem that the surrounding edges of the existing wall tend to yield prematurely when they are pressed by lateral force;

(8) Compared with the existing means, the enhancement method of the present invention does not change the main manufacturing parameters of the plate, so there is no need to add additional equipment, change the process, etc., so the cost is controllable and the feasibility is stronger. The strength of the plate prepared by the method fully meets the requirements and regulations of various standards and specifications at home and abroad.

Description of drawings

Fig. 1 is the schematic diagram of traditional particleboard preparation method;

Figure 2 is the deformation diagram of the shear wall under the action of horizontal force;

Fig. 3 is a schematic diagram of the preparation method of the partially reinforced particleboard of the present invention.

In the figure: 1. Reinforced area; 2. Non-reinforced area; 3. High stress area; 4. Low stress area; 5. Non-reinforced particle board; 6. Non-reinforced particle board; 7. Reinforced particle board; 8. Reinforced chipboard.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example 1

As shown in Figure 3, a locally reinforced particleboard based on stress distribution, the particleboard includes a reinforced area 1 and a non-reinforced area 2 in the horizontal direction perpendicular to the thickness, and the reinforced area 1 is arranged on both sides of the non-reinforced area 2, and The density of the enhanced area 1 is greater than that of the non-enhanced area 2, and the density of the non-enhanced area 2 increases gradually toward the enhanced area 1.

As shown in Figure 2, when the shear wall made of conventional particle boards is damaged by horizontal action, the corners of the boards are easy to be damaged due to the concentration of force, the nails are easy to pull out, or the stress is unevenly distributed, such as premature yielding. For example, considering the material level, by increasing the density on both sides of the particleboard, the mechanical strength on both sides of the particleboard is significantly improved, thereby ensuring that the corners on both sides of the board have a higher stress range and enhancing the strength of the edges on both sides. To ensure that the force can be transmitted from the reinforced area 1 to the non-reinforced area 2, so that the mechanical properties of each area of the plate can be fully utilized, the problem of premature yielding at the edge of the plate is solved, and the shearing caused by local damage is avoided. Part of the nail connection in the force wall contributes too little to the overall horizontal lateral force.

Example 2

The structure of the particleboard in this embodiment is basically the same as that in Embodiment 1. Furthermore, the density of the reinforced area 1 in this embodiment is 1.1-1.7 times that of the non-reinforced area 2 .

Specifically, the average density of the reinforced region 1 of the present invention is kept in the range of 0.70-0.85g/cm ³ , and the density of the non-reinforced region 2 is in the range of 0.50-0.65g/cm ³ , which not only meets the strength requirements after density enhancement, At the same time, material is saved. Although it is said that according to the proportional relationship between density and strength, if simply consider increasing the density endlessly to increase the strength, it will not only increase the complexity of the preparation method and the cost of materials, but also cannot meet the use requirements in practical applications. From the perspective of reinforced area, if only the entire board is considered to be reinforced to increase the strength of the board, not only will the cost be greatly increased, but the central part of the board will not be fully utilized.

Example 3

The basis for the division of reinforced zone 1 and non-reinforced zone 2 in the present invention comes from the previous research on particleboard. As shown in Figure 2, when the shear wall is damaged by horizontal lateral force, there will be a gap between the four corners of the cladding panel and the wall skeleton. Nails are easy to pull out, and are easier to break than the middle. Through the finite element simulation, we can clearly see the stress distribution of the cladding panels during the failure process of the shear wall. The four corners of the cladding panels are high stress areas 3, and the middle of the cladding panels is the low Stress zone 4, this uneven distribution of stress causes the four corners of the edge of the cladding panel to yield prematurely. Existing reinforcement methods are not considered from the perspective of the plate, and the relationship between the strength and density of the plate is mostly studied in the material test.

In the preparation method of a locally reinforced particle board based on stress distribution in this embodiment, in the paving process, shavings are added on both sides of the paving slab to form a reinforced area 1, and a non-reinforced area is formed at the slab without added shavings 2. This embodiment is mainly to solve the structural problems from the material level. As shown in Figure 3, the reinforced area 1 on both sides of the reinforced particle slab 7 is thicker than the non-reinforced area 2 in the middle, and it is clear It can be seen that the thickness of the shavings in the reinforced area 1 gradually increases along the non-reinforced area 2 to the outside, and the reinforced particle board 8 is obtained after pressing and forming, and the strength of the edges on both sides is enhanced to ensure that the force can be transmitted from the reinforced area 1 to the non-reinforced area 2. In this way, the mechanical properties of each panel can be fully utilized, avoiding the problem of stress concentration at the sudden change in density of the particleboard after compression molding, and at the same time achieving the purpose of enhancing the overall strength of the shear wall, and the strength of the prepared panels is also high. It can meet the requirements and regulations of various standards and regulations at home and abroad.

Compared with the preparation method of the conventional particleboard in Fig. 1, there is not much difference between the reinforced particleboard 8 and the non-reinforced particleboard 6 in terms of specifications and sizes. The height of the shavings pavement is gradually increased. This preparation method does not change the main manufacturing parameters of the board, so there is no need to add additional equipment, change the process, etc., so the cost is controllable and the feasibility is stronger.

Example 4

The preparation method of the particle board of this embodiment is basically the same as the process of embodiment 3. More specifically, the size of the particle board of this embodiment is 1.22m×2.44m, and the position where the particle board is added when paving the slab is the two sides of the board surface under stress At the edge of the shavings, the added width of the shavings is 1/8 of the width of the board, and the angle between the progressive thickness slope of the shavings in the reinforcement zone 1 and the plane of the non-reinforcement zone 2 is 20°, and the average density of the particleboard reinforcement zone 1 after pressing is 0.85 g/cm ³ , and the density of the non-enhanced region 2 is 0.5 g/cm ³ .

According to the conventional technical scheme, the ultimate bearing capacity of a 6m×2.4m shear wall composed of five 9.5mm thick particleboards with a density of 0.5g/cm3 is 53.62kN.

Using the preparation method of this example, five particleboards with a thickness of 9.5mm, a density of 0.5g/ ^cm3 in the non-reinforced area 2 and a density of 0.85g/ ^cm3 in the reinforced area 1 are assembled with the wall frame to form a size of The ultimate bearing capacity of the 6m×2.4m shear wall is 75.61kN, which is 41% higher than the ultimate bearing capacity of the conventional shear wall.

Example 5

The preparation method of the particleboard in this example is basically the same as in Example 4, the difference is that the size of the particleboard in this example is 1.22m × 2.44m, and the position where the shavings are added when paving the slab is two sides of the force on the surface of the slab. At the edge of the side, the added width of the shavings is 1/7 of the width of the board, the angle between the progressive thickness slope of the shavings in the reinforcement zone 1 and the plane of the non-reinforcement zone 2 is 40°, and the density of the particleboard reinforcement zone 1 after pressing is 0.85 g/cm ³ , the density of the non-enhanced region 2 is 0.65 g/cm ³ , the thickness of the enhanced region 1 and the non-reinforced region 2 are the same.

According to the conventional technical scheme, the ultimate bearing capacity of a 6m×2.4m shear wall composed of five 9.5mm thick particle boards and a density of 0.85g/cm3 is 83.85kN.

Using the preparation method of this example, five particle boards with a thickness of 9.5 mm and a density of 0.65 g/cm3 in the non-reinforced area 2 and 0.85 g/cm3 in the reinforced area 1 are installed and combined with the wall skeleton. The ultimate bearing capacity of the 6m×2.4m shear wall is 86.86kN, which is slightly higher than the ultimate bearing capacity of the conventional shear wall. At the same time, the density of the conventional panel is 0.85g/cm3, while the density of the improved non-reinforced area 2 is 0.65 g/cm3, the reinforced area 1 at the edge is 0.85g/cm3, reaching the same level of bearing capacity The particleboard of this embodiment saves 24% of raw materials.

Example 6

In the method for preparing locally reinforced particleboard based on stress distribution, in the paving process, shavings are added to both sides of the paving slab to form a reinforced area 1, and a non-reinforced area 2 is formed at the slab without adding shavings. According to the calculation results of the stress distribution of the shear wall cladding panels under the action of horizontal loads, during the particleboard manufacturing process, more materials are arranged at the vulnerable corners of the panels, thereby increasing the thickness of the slabs. Under the condition of keeping the thickness of the finished panels unchanged, Increase the local density of the corners to form an implicit enhancement band. This embodiment also includes a shaving preparation process and a glue mixing process before the paving process, and pre-presses, hot-presses and post-treats the slab after the paving process.

In order to ensure the flatness of the board and achieve higher operability, in the pre-pressing and hot-pressing processes, the reinforced area 1 and the non-reinforced area 2 adopt the same treatment process. The process conditions in the pre-pressing process are: P=10-20MPa; t=10-25s. The process conditions in the hot pressing process are: T=140-160°C; P=1.2-4.0Mp; t=30-50s.

The size of the particle board in this embodiment is 1.22m×2.44m. When paving the slab, the shavings are added at the edge of both sides of the board surface under stress. The width of the shavings added is 2/15 of the width of the board. The included angle between the thickness slope and the plane where the non-reinforced area 2 is located is 30°, the density of the reinforced area 1 of the particleboard after compression molding is 0.7g/cm ³ , and the density of the non-reinforced area 2 is 0.65g/cm ³ .

According to the conventional technical scheme, the ultimate bearing capacity of a 6m×2.4m shear wall composed of five 9.5mm thick particle boards and a density of 0.65g/cm3 is 67.33kN.

Using the preparation method of this example, five particle boards with a thickness of 9.5 mm, a density of 0.65 g/ ^cm3 in the non-reinforced area 2 and a density of 0.7 g/ ^cm3 in the reinforced area 1 are assembled with the wall frame to form a size of The ultimate bearing capacity of the 6m×2.4m shear wall is 80.79kN, which is 19.9% higher than that of the conventional scheme.

Example 7

The preparation method of the particleboard in this example is basically the same as in Example 6, the difference is that the size of the particleboard in this example is 1.22m × 2.44m, and the position where the shavings are added when laying the slab is two sides of the force on the surface of the slab. At the edge of the side, the added width of the shavings is 1/7 of the width of the board, the angle between the progressive thickness slope of the shavings in the reinforcement zone 1 and the plane of the non-reinforcement zone 2 is 30°, and the density of the particleboard reinforcement zone 1 after pressing is 0.85 g/cm ³ , and the density of the non-enhanced region 2 is 0.65 g/cm ³ .

According to the conventional technical scheme, the ultimate bearing capacity of a 6m×2.4m shear wall composed of five 9.5mm thick particle boards and a density of 0.5g/cm3 is 53.62kN.

Using the preparation method of this example, five particleboards with a thickness of 9.5 mm, a density of 0.65 g/ ^cm3 in the non-reinforced area 2 and a density of 0.85 g/ ^cm3 in the reinforced area 1 are installed and combined with the wall skeleton to form a size of The ultimate bearing capacity of the 6m×2.4m shear wall is 86.86kN, which is 62% higher than the ultimate bearing capacity of the conventional shear wall.

Claims (10)

1. the local enhancement shaving board based on stress distribution, it is characterised in that：The particieboard water perpendicular in thickness Square upwards include enhancement region (1) and non-reinforcing area (2), the enhancement region (1) is arranged the two of the non-reinforcing area (2) Side, and the density of the enhancement region (1) is more than the density of the non-reinforcing area (2), non-reinforcing area (2) is to the close of enhancement region (1) Degree progressively increases.

2. particieboard according to claim 1, it is characterised in that：The density of the enhancement region (1) is described non-reinforcing 1.1~1.7 times of area (2).

3. particieboard according to claim 1, it is characterised in that：The thickness of the enhancement region (1) and non-reinforcing area (2) It is identical.

4. the preparation method of the local enhancement shaving board based on stress distribution, it is characterised in that：In process of mating formation, in plate of mating formation The both sides of base increase wood shavings, are formed enhancement region (1), do not increase and form non-reinforcing area (2) at the slab of wood shavings.

5. the preparation method of particieboard according to claim 4, it is characterised in that：The width of the enhancement region (1) is plate The 1/8~1/7 of base width.

6. the preparation method of particieboard according to claim 4 or 5, it is characterised in that：The wood shavings of the enhancement region (1) increase It adds thickness and is progressively increased outward along non-reinforcing area (2).

7. the preparation method of particieboard according to claim 4, it is characterised in that：The wood shavings of the enhancement region (1) are progressive Angle between plane where thickness inclined-plane and the non-reinforcing area (2) is 20 °~40 °.

8. the preparation method of particieboard according to claim 4, it is characterised in that：Further include wood shavings before process of mating formation Preparation section and glue mixing process carry out precompressed, hot pressing and post-processing after mating formation to slab.

9. the preparation method of particieboard according to claim 8, it is characterised in that：It is described in precompressed and hot pressing process Enhancement region (1) and the non-reinforcing area (2) use identical processing method.

10. the shear wall of clad can, it is characterised in that：It, will be described including particieboard prepared by claim 4-9 any one methods Particieboard and the installation combination of wall skeleton.