Method and device for repairing a transversely damaged timber member

Abstract

The application relates to the technical field of cultural relic restoration, and discloses a restoration method and a restoration device for a transversely damaged wooden component. In the restoration method, the transverse grain yield strength required for the restoration of the transversely damaged wooden component is obtained, and the maximum clamping force required for the restoration of the transversely damaged wooden component is determined according to the transverse grain yield strength; then the restoration device is selected according to the maximum clamping force, the number of the restoration devices and the glue injection amount of the adhesive are determined according to the size information and the transverse grain characteristic information of the transversely damaged wooden component; then the damaged area of the transversely damaged wooden component is subjected to glue injection work according to the glue injection amount, and the restoration device is installed in the damaged area according to the maximum clamping force, so that the transversely damaged wooden component is clamped and fixed; after waiting for a preset time length, the restoration device is removed, and the glue layer remaining on the surface of the transversely damaged wooden component is removed, and the restoration is completed. The restoration method is more scientific, the restoration is simpler, and the restoration effect is better.

Description

Technical Field

[0001] This application relates to the field of cultural relic restoration technology, and in particular to a method and device for repairing horizontally damaged wooden components. Background Technology

[0002] Ancient buildings, as an important part of cultural heritage, carry rich historical and cultural information. However, after long-term service, they are prone to varying degrees of damage, with damage to horizontal components being particularly common. Horizontal components mainly consist of horizontally placed elements such as wooden beams and lintels, which are susceptible to cracking, sagging, and dimensional deformation. Since these components are usually located at the top of the building, the methods of repairing their damage are quite limited, thus placing certain requirements on the weight and convenience of the repair equipment. Furthermore, the repair of horizontally damaged components in ancient buildings presents many challenges, including the complexity of the component's shape, the difficulty of fixing it, and the inconsistency of repair results.

[0003] Nowadays, the restoration methods for wooden components of ancient buildings mostly rely on manual operation or simple support tools, and are carried out based on the restorer's personal experience. However, since the structural characteristics of each component are different, the above-mentioned restoration methods have drawbacks such as inconvenience in operation and poor results. Summary of the Invention

[0004] The purpose of this application is to provide a method and device for repairing horizontally damaged wooden components, so as to solve the defects of existing repair methods such as inconvenience in operation and poor effect.

[0005] To achieve the above objectives, in a first aspect, this application provides a method for repairing transversely damaged wooden components, comprising:

[0006] S100: Obtain the transverse yield strength required for repairing transversely damaged wooden components, and determine the maximum clamping force required for repairing transversely damaged wooden components based on the transverse yield strength;

[0007] S200: Select the repair device according to the maximum clamping force, and then determine the number of the repair devices and the amount of adhesive to be injected according to the size information and cross grain feature information of the transversely damaged wooden component.

[0008] S300: Apply glue to the damaged area of ​​the transversely damaged wooden component according to the glue amount, and then install the repair device in the damaged area according to the maximum clamping force to clamp and fix the transversely damaged wooden component.

[0009] S400: After waiting for a preset time, remove the repair device and remove the adhesive layer remaining on the surface of the transversely damaged wooden component.

[0010] In one possible implementation, obtaining the transverse yield strength required for repairing the transversely damaged wooden component in step S100 includes:

[0011] S110: Establish a model of a transversely intact wooden component of the original size based on the damaged area of ​​the transversely damaged wooden component;

[0012] S120: The middle part of the transversely intact wooden component model is locally compressed to measure the compressive strength of the transversely intact wooden component model and construct a displacement-load curve.

[0013] S130: Determine the transverse yield strength of the transversely intact wooden component model based on the displacement load curve, and use the transverse yield strength as the repair standard when repairing the transversely damaged wooden component.

[0014] In one possible implementation, step S130 includes:

[0015] S131: Based on the constructed displacement-load curve, the yield point of the transversely intact wooden component model is determined using the offset yield method;

[0016] S132: Calculate the transverse yield strength of the transversely intact wooden component model based on the yield point;

[0017] The formula for calculating the transverse yield strength is as follows:

[0018]

[0019] A is the pressure area of ​​the transversely intact wooden component model, F y σ is the yield load corresponding to the yield point. y The yield strength is the value corresponding to the yield point.

[0020] In one possible implementation, determining the maximum clamping force required for repairing the transversely damaged wooden component based on the transverse yield strength in step S100 includes:

[0021] S140: The yield strength of wood under circumferential constraint increased by 50%-80% as measured by flawless small samples;

[0022] S150: Determine the maximum clamping force required for repairing the transversely damaged wooden component, based on the fact that the yield strength of the wood will increase by 80% under circumferential constraint.

[0023] In one possible implementation, the repair device in step S200 includes an upper and lower clamping assembly and a side clamping assembly, wherein the upper and lower clamping assembly and the side clamping assembly are respectively connected by a plurality of first fasteners;

[0024] The first fastener that meets the clamping requirements is selected from the upper and lower clamping assemblies and the side clamping assembly according to the maximum clamping force.

[0025] Define the maximum clamping force as F, and the number of first fasteners in the upper and lower clamping assemblies as N. Calculate the force F that each first fastener needs to withstand. 单根 :

[0026] F 单根 =F / N

[0027] F max =A S ×σ t,max

[0028] Among them, the maximum bearing capacity F of the selected first fastener max >F 单根 A S σ is the effective area of ​​the cross-section of the first fastener. t,max F represents the maximum working strength of the first fastener. max This represents the maximum load-bearing capacity of the first fastener.

[0029] In one possible implementation, the transverse grain feature information of the transversely damaged wooden component in step S200 includes the crack location, average crack width, and length and depth.

[0030] The formula for calculating the amount of adhesive to be injected is as follows:

[0031]

[0032] The above m 胶 The mass of the adhesive used during injection; each crack is assumed to have an inverted triangular cross-section, with the surface cracking being the most extensive and gradually decreasing inwards, therefore the injection volume is calculated as a triangular prism; L, W, and H are the length, width, and depth of the crack, respectively; ρ 胶 The density of the adhesive used.

[0033] In one possible implementation, step S300, prior to installing the repair device, further includes:

[0034] S310: After completing the glue application, use a brush to spread the glue evenly and then seal the release paper at the glue application position with tape.

[0035] S320: Then, use release paper to completely wrap the damaged area, and then install the repair device.

[0036] In one possible implementation, step S400 further includes observing the repair quality after removing the repair device, and observing whether the cracks in the damaged area are closed; if they are not closed, secondary filling is performed as appropriate.

[0037] To achieve the above objectives, in a second aspect, this application provides a repair apparatus for transversely damaged wooden components, applicable to the repair method for transversely damaged wooden components provided in the first aspect above, the repair apparatus for transversely damaged wooden components comprising:

[0038] The upper and lower clamping assembly includes two first pair of clamping plates aligned along a first direction; and

[0039] The side clamping assembly includes two second pair of clamping plates aligned along a second direction;

[0040] Wherein, the first direction and the second direction are perpendicular to each other, the two first pairs of clamping plates and the two second pairs of clamping plates are respectively connected by a plurality of first fasteners, and buffer pads are provided on the opposite side of the two first pairs of clamping plates and the opposite side of the two second pairs of clamping plates.

[0041] In one possible implementation, each of the first pair of clamps is provided with a plurality of elongated holes along the second direction for mounting the first fastener, the length direction of the elongated holes being consistent with the second direction; and / or

[0042] Each of the second pair of clamps includes two main clamps spliced ​​along the second direction, with a supplementary plate installed between the two main clamps, and the main clamps and the supplementary plate are connected by a second fastener.

[0043] Compared to existing technologies, the beneficial effects of this application are:

[0044] This application provides a method and apparatus for repairing transversely damaged wooden components. The method involves obtaining the required transverse yield strength for repairing the transversely damaged wooden component and determining the maximum clamping force required for repair based on the transverse yield strength. Then, a repair device is selected based on the maximum clamping force. The number of repair devices and the amount of adhesive to be injected are determined based on the size and transverse grain characteristics of the transversely damaged wooden component. Adhesive is then injected into the damaged area of ​​the transversely damaged wooden component according to the amount of adhesive injected. The repair device is then installed in the damaged area according to the maximum clamping force to clamp and fix the transversely damaged wooden component. After a preset time, the repair device is removed and any remaining adhesive layer on the surface of the transversely damaged wooden component is removed, completing the repair. Thus, the repair method for transversely damaged wooden components provided in this application is based on the transverse yield strength required for repairing transversely damaged wooden components, and then the maximum clamping force and amount of glue required for repair are calculated to achieve scientific repair. According to different structural characteristics of transversely damaged wooden components, a repair method can be formulated to suit them, making the repair simpler and the repair effect better. Attached Figure Description

[0045] Figure 1 A flowchart illustrating a method for repairing transversely damaged wooden components according to an embodiment of this application is shown;

[0046] Figure 2 A schematic diagram of an offset yielding method provided in an embodiment of this application is shown;

[0047] Figure 3 The displacement-load curves of transversely intact wooden members obtained through quasi-static tests according to embodiments of this application are shown, and the application of... Figure 2 The offset yielding method is shown.

[0048] Figure 4 This illustration shows a three-dimensional structural diagram of a repair device for transversely damaged wooden components according to an embodiment of this application;

[0049] Figure 5 It shows Figure 4 A three-dimensional structural diagram of the first pair of clamps in the repair device for the transversely damaged wooden component shown.

[0050] Figure 6 It shows Figure 4 An exploded view of a portion of the side clamping assembly in the repair device for the transversely damaged wooden component shown.

[0051] Figure 7 This diagram illustrates the state of the repair device for transversely damaged wooden components provided in this application, installed on the transversely damaged wooden components.

[0052] Explanation of key component symbols:

[0053] 10. Upper and lower clamping components; 11. First pair of clamping plates; 110. Long strip hole;

[0054] 20. Side clamping assembly; 21. Second pair of clamping plates; 210. Main clamping plate; 211. Supplementary plate; 212. Clearance notch;

[0055] 30. First fastener;

[0056] 40. Cushioning rubber pads;

[0057] 50. Second fastener. Detailed Implementation

[0058] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0059] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0060] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0061] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0062] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0063] In the description of this application, it should be understood that the term "transverse timber component" refers to timber components in ancient wooden structures where timber is laid horizontally in the longitudinal direction, such as beams, lintels, and lintels; the term "damage" refers to damage that causes the mechanical strength and basic shape of a timber component to be compromised, which in transverse timber components mainly includes sagging, bending, cracking, splitting, and crushing; the term "timber unit system" is a modular system in ancient architecture, in which timber is divided into 8 grades according to building grade by the timber unit system given by the architectural standards, and the size of the basic unit "fen" of each grade is determined; the terms "width" and "thickness" refer to the height and width of transverse timber components, which are multiplied by a certain ratio of the size of the basic unit "fen" of each grade in the timber unit system; the term "single timber" refers to timber of each grade with a width of 15 parts and a width of 10 parts, and the size of each part is one of the required parts for each grade; the term "full timber" refers to timber with a width of 21 parts and a width of 10 parts.

[0064] Example 1

[0065] Please see Figure 1 This embodiment provides a method for repairing transversely damaged wooden components, which can be used to repair transversely damaged wooden components such as cracks and shattering.

[0066] In this embodiment, the repair method for transversely damaged wooden components includes the following steps:

[0067] S100: Obtain the transverse yield strength required for repairing transversely damaged wooden components, and determine the maximum clamping force required for repairing transversely damaged wooden components based on the transverse yield strength.

[0068] S200: Select the repair device according to the maximum clamping force, and then determine the number of repair devices and the amount of adhesive to be injected according to the size information and cross grain feature information of the transversely damaged wooden component.

[0069] S300: Apply glue to the damaged area of ​​the transversely damaged wooden component according to the amount of glue applied, and then install the repair device in the damaged area according to the maximum clamping force to clamp and fix the transversely damaged wooden component.

[0070] S400: After waiting for a preset time, remove the repair device and remove the adhesive layer remaining on the surface of the transversely damaged wooden component.

[0071] Thus, the method for repairing transversely damaged wooden components provided in this embodiment is based on the required transverse yield strength for repairing transversely damaged wooden components. Then, the maximum clamping force and amount of glue required for repair are calculated to achieve scientific repair. According to different structural characteristics of transversely damaged wooden components, a repair method can be formulated to suit them, making the repair simpler and the repair effect better.

[0072] The transverse yield strength required for repairing transversely damaged wooden components in step S100 above includes:

[0073] S110: Establish a model of a horizontally intact wooden component of the original size based on the damaged area of ​​the horizontally damaged wooden component.

[0074] S120: The middle part of the transversely intact wooden component model is locally compressed to measure the compressive strength of the transversely intact wooden component model and construct a displacement-load curve.

[0075] Understandably, the compressive strength of the transversely damaged wooden component is lower than that of the intact transversely good wooden component. Therefore, using the compressive strength of the intact transversely good wooden component, which has a higher compressive strength, as the design standard can ensure that the compressive strength of the repaired transversely damaged wooden component is closer to that of the intact transversely good wooden component, thereby improving the repair effect.

[0076] S130: Determine the transverse yield strength of the transversely intact wooden component model based on the displacement load curve, and use the transverse yield strength as the repair standard when repairing the transversely damaged wooden component.

[0077] Specifically, in steps S120 and S130 above, a quasi-static test is used to conduct a local compression test on the transversely intact wooden component model, and a displacement load curve is constructed. Then, based on the constructed displacement load curve, the yield point of the transversely intact wooden component is determined by the "offset yield method", and the yield strength and yield strain of the transversely intact wooden component model are calculated.

[0078] Please see Figure 2 This diagram illustrates an offset yielding method. The displacement-load curve is linearly fitted to the elastic stage, with R-squared greater than 0.999 used as the criterion for determining the linear fitting equation for the elastic stage. The offset linear equation is determined by offsetting the displacement by 0.2%H, and the intersection of this equation with the displacement-load curve is the yield point.

[0079] Please participate Figure 3In step S120 above, multiple experiments are conducted, and the average value of the experiments is used to construct a displacement-load curve. The yield point is then determined using the offset yield method based on this displacement-load curve.

[0080] Furthermore, step S130 includes:

[0081] S131: Based on the constructed displacement-load curve, the yield point of the transversely intact wooden component model is determined using the offset yield method.

[0082] S132: Calculate the transverse yield strength of the transversely intact wooden component model based on the yield point.

[0083] The formula for calculating the transverse yield strength is as follows:

[0084]

[0085] In the above formula (1), A is the pressure area of ​​the transversely intact wooden component model, and F y σ is the yield load corresponding to the yield point. y The yield strength is the value corresponding to the yield point.

[0086] The step S100 above, which determines the maximum clamping force required for repairing the transversely damaged wooden component based on the transverse yield strength, includes the following steps:

[0087] S130: The yield strength of wood under circumferential constraint increased by 50%-80% as measured by flawless small samples;

[0088] S140: Determine the maximum clamping force required for repairing the transversely damaged wooden component, based on the fact that the yield strength of the wood will increase by 80% under circumferential constraint.

[0089] The yield strength of the wood after the increase in yield strength under circumferential constraint is calculated according to the above formula (1) as σ. w As shown in equation (2):

[0090] σ w =σ y +σ y ×80% (2)

[0091] Please refer to the following: Figure 4 and Figure 7In this embodiment, the repair device in step S200 includes an upper and lower clamping assembly 10 and a side clamping assembly 20, which are connected by a plurality of first fasteners 30. The upper and lower clamping assembly 10 is used to clamp the transversely damaged wooden component along a first direction, and the side clamping assembly 20 is used to clamp the transversely damaged wooden component along a second direction, thus providing circumferential constraint for the transversely damaged wooden component. The first direction and the second direction are perpendicular to each other. In this embodiment, the first direction is... Figure 4 The vertical direction is shown, and the second direction is... Figure 4 The front and back directions are shown.

[0092] It should be noted that the maximum clamping force of the upper and lower clamping components 10 and the side clamping components 20 on the transversely damaged wooden components is determined by the first fastener 30. Therefore, the selection of the first fastener 30 should ensure that the load-bearing capacity meets the clamping requirements.

[0093] Specifically, the first fastener 30 that meets the clamping requirements in the upper and lower clamping assemblies 10 and the side clamping assembly 20 is selected based on the maximum clamping force. Here, the contact area between the upper and lower clamping assembly 10 and the transversely damaged wooden component is defined as S, the maximum clamping force is defined as F, and the number of first fasteners 30 in the upper and lower clamping assembly 10 or the side clamping assembly 20 is defined as N. The force F that each first fastener 30 in the upper and lower clamping assembly 10 and the side clamping assembly 20 needs to withstand is calculated. 单根 :

[0094] F = σ w ×S (3)

[0095] F 单根 =F / N (4)

[0096] F max =A S ×σ t,max (5)

[0097] Among them, the maximum bearing capacity F of the selected first fastener 30 max >F 单根 In equations (3), (4), and (5) above: A S σ is the effective area of ​​the cross-section of the first fastener 30; t,max F represents the maximum working strength of the first fastener 30. max This is the maximum load-bearing capacity of the first fastener 30.

[0098] Furthermore, in this embodiment, the first fastener 30 is selected as a combination of a bolt and a nut. The effective area A of the bolt's cross-section... SThe calculation is as follows (6):

[0099]

[0100] In the above formula (6): d is the bolt diameter; P is the pitch.

[0101] Furthermore, the transverse grain feature information of the transversely damaged wooden component in step S200 includes the crack location, average crack width, and length and depth. The formula for calculating the amount of adhesive injected is as follows (7):

[0102]

[0103] In the above formula (7): m 胶 The mass of the adhesive used during injection; each crack is assumed to have an inverted triangular cross-section, with the surface cracking being the most extensive and gradually decreasing inwards, therefore the injection volume is calculated as a triangular prism; L, W, and H are the length, width, and depth of the crack, respectively; ρ 胶 The density of the adhesive used.

[0104] It should be noted that the adhesive selected must have an operable time of more than 40 minutes at 25°C, and as an injection material, the adhesive itself must have a solid content of 100%, and the shear strength for bonding with ash wood along the grain must be more than 7.8 MPa. The initial viscosity should be 200-8000 mPa·s, and the adhesive should be able to cure at room temperature with a curing time of less than 4 hours.

[0105] Optionally, the above adhesives include modified epoxy resins and polyurethane adhesives.

[0106] Furthermore, step S300 above, before installing the repair device, also includes:

[0107] S310: After completing the glue application, use a brush to spread the glue evenly and then seal the release paper at the glue application location with tape.

[0108] S320: Then, use release paper to completely wrap the damaged area, and then install the repair device.

[0109] The above step S400 also includes observing the repair quality after removing the repair device, and observing whether the cracks in the damaged area are closed; if they are not closed, secondary filling is performed as needed. If there are no quality problems, the release paper is completely removed, and then the adhesive layer on the surface is removed with sandpaper or a sander.

[0110] Example 2

[0111] Please see Figure 1 and Figure 4This embodiment provides a repair device for horizontally damaged wooden components, which is applicable to the repair method for horizontally damaged wooden components provided in Embodiment 1 above.

[0112] In this embodiment, the repair device for transversely damaged wooden components includes an upper and lower clamping assembly 10 and a side clamping assembly 20; the upper and lower clamping assembly 10 includes two first pairs of clamping plates 11 arranged in alignment along a first direction; the side clamping assembly 20 includes two second pairs of clamping plates 21 arranged in alignment along a second direction. The first and second directions are perpendicular to each other.

[0113] Please refer to the following: Figure 5 and Figure 6 The two first pair of clamping plates 11 and the two second pair of clamping plates 21 are connected by a plurality of first fasteners 30 respectively, and buffer pads 40 are provided on the opposite side of the two first pair of clamping plates 11 and the opposite side of the two second pair of clamping plates 21.

[0114] Optionally, the first fastener 30 is a combination of a bolt and a nut. Alternatively, it can be a combination of a stud and a nut.

[0115] Optionally, the cushioning pad 40 is a rubber pad.

[0116] During clamping and repair, the two second pairs of clamping plates 21 are located between the two first pairs of clamping plates 11. Furthermore, the upper edge of the second pair of clamping plates 21 is provided with a clearance notch 212 to avoid the first pair of clamping plates 11.

[0117] Please refer to the following: Figure 5 Furthermore, each first pair of clamping plates 11 is provided with multiple elongated holes 110 along the second direction for installing the first fastener 30, and the length direction of the elongated holes 110 is consistent with the second direction. Each second pair of clamping plates 21 includes two main clamping plates 210 spliced ​​along the second direction, and a supplementary plate 211 is installed between the two main clamping plates 210. Thus, the repair device for transversely damaged wooden components provided in this embodiment has a simple structure, is easy to operate, and the multiple elongated holes 110 and the supplementary plate 211 can be applied to the repair of damaged components of various sizes, making it more practical.

[0118] When the supplementary plate 211 is added, the two main clamping plates 210 are connected to the supplementary plate 211 by a second fastener 40. The second fastener 40 passes through the main clamping plate 210 along its width and connects to the supplementary plate 211. Other detachable connection methods are also possible. Optionally, the second fastener 40 is a bolt.

[0119] To more clearly describe the repair device for transversely damaged wooden components provided in this embodiment, examples are given below.

[0120] Please see Figure 4 , Figure 5 , Figure 6 and Figure 7 It should be noted that in the building construction standard's timber unit system, the width and thickness of timber from first to eighth grade are 15 parts and 10 parts respectively. Depending on the grade, one part of each grade is 6 fen, 5 fen 5 li, 5 fen, 4 fen 8 li, 4 fen 4 li, 4 fen, 3 fen 5 li, and 3 fen. The calculated width dimensions of each grade, converted to SI units, are 28.1cm, 25.8cm, 23.4cm, 22.5cm, 20.6cm, 18.8cm, 16.4cm, and 14.0cm respectively. The base timber is the height of the single timber plus the height of the girder, meaning the width and thickness are 21 parts and 10 parts respectively. The base timber width dimensions for each grade are 39.3cm, 36.0cm, 32.7cm, 31.4cm, 28.8cm, 26.2cm, 22.9cm, and 19.6cm respectively. To accommodate the dimensions of individual and complete timber pieces of various grades, two types of repair devices are designed, one for grades one to four and the other for grades five to eight. For the first type of repair device (grades one to four), the first pair of clamping plates 11 measures 50cm x 25cm; for the second type (grades five to eight), the first pair of clamping plates 11 measures 35cm x 25cm. Each pair of clamping plates 11 has three 24mm diameter circular holes on one side along its length for bolt fastening. The other side has three rows of four elongated holes 110, each 24mm wide. The three rows of elongated holes 110 are evenly distributed according to the width of the board. The distances between the four rows of elongated holes 110 and the individual round holes are 28cm, 32cm, 36cm and 40cm respectively (20cm, 24cm, 28cm and 32cm for type 2). The four rows of elongated holes 110 are designed to meet the dimensions of single and full-size materials for first-class to eighth-class materials in the construction method.

[0121] Each second pair of plywood 21 consists of two main plywoods 210 and a supplementary plywood 211. The number of supplementary plywoods 211 used is determined by the thickness of the transversely damaged timber component. The supplementary plywood 211 measures 35cm × 3cm. For seventh and eighth grade timber, only two main plywoods 210 are needed for the second pair of plywood 211. For fifth and sixth grade timber, an additional supplementary plywood 211 can be added, and so on. When the second pair of plywood 21 uses two main plywoods 210 and three supplementary plywoods 211, it is suitable for use with the largest first grade timber.

[0122] Using fifth-grade timber as the subject, a standard plinth component was fabricated, with a cross-section of 20cm × 8.5cm. The component was required to contain a pith, with the pith positioned centrally on both ends. The standard plinth is a common component in ancient architecture, located above wooden pillars and below bracket sets, and is prone to damage such as sagging and cracking. By locally compressing the middle section of the standard plinth, the compressive strength of the transversely intact timber component was measured. The test yielded a yield strength of 5.439 MPa for the transversely intact timber component, including the pith. Through flawless small samples, it was found that the yield strength of the wood increases by 50%-80% when circumferential restraint is used.

[0123] Furthermore, considering that the width of a first-class timber is 39.3cm, rounded down, we take 40cm as the maximum width of the repair component and 25cm as the minimum repair unit. The maximum clamping force required for repairing transversely damaged wooden components is calculated based on 9.7MPa after circumferential constraint reinforcement. According to the above equations (2) to (4), the maximum clamping force F required for a single clamping assembly is 970kN. Each upper and lower clamping assembly 10 is clamped with 6 bolts, so a single bolt needs to withstand a force of 163.2kN. Thus, only the selected bolts F max Greater than F 单根 That's all you need to ask for.

[0124] To meet the clamping requirements for repairing large-sized components, bolts with a diameter of 20mm, a pitch of 2.5mm, and a nominal stress cross-sectional area of ​​245mm² were selected based on the maximum guaranteed load. 2 The bolts are 250mm long and made of 304 stainless steel with full thread. The first pair of clamping plates 11 and the second pair of clamping plates 21 are both made of 304 stainless steel and are fixed with rubber pads by adhesive.

[0125] The method for selecting bolts in the upper and lower clamping assemblies 10 described above also applies to the selection of bolts in the side clamping assembly 20. The main difference is that the side clamping assembly 20 has four bolts.

[0126] Before the repair process, additives are added to the adhesive according to different requirements, and the prepared adhesive is injected into the glue injector. The crack opening is injected with the glue injector according to the amount of glue calculated by the above formula (7). At the same time, the glue is evenly applied with a brush, and the release paper is sealed at the glue injection position with tape. Finally, the specimen is fully wrapped with release paper.

[0127] After completing the above preliminary work, install the repair device for transversely damaged wooden components provided in this embodiment. Select appropriate upper and lower clamping components 10 and side clamping components 20 according to the type and size of the component, and multiple sets can be repaired simultaneously according to the length. Then, simultaneously use bolts and nuts to connect the round holes on one side of the upper and lower clamping components 10, leaving sufficient margin; attach the upper and lower clamping components 10 to the upper and lower surfaces of the component respectively, leaving 3-5cm between the three bolt positions and the side of the component, so as to reserve space for the installation of the side clamping components 20; according to the width of the wooden component, connect the three bolts and nuts to the corresponding elongated holes 110 on the other side of the upper and lower clamping components 10, requiring the bolt positions to leave 3-5cm between the side of the component, also to reserve space for the installation of the side clamping components 20; pre-tighten the six bolts in the order of installing the middle bolt first and then the four diagonal bolts; tighten the four bolts of the side clamping components 20 in the order of installing the diagonal bolts in sequence until the middle dimension of the side clamping components 20 reaches the width of the wooden component when it is prepared, and the required force is calculated according to formula (8); finally, tighten the six bolts of the upper and lower clamping plates in the order of installing the middle bolt first and then the four diagonal bolts in sequence, and the repair clamping process is completed. The force applied by each bolt is calculated according to formula (9).

[0128]

[0129]

[0130] It should be noted that the maximum lateral clamping force F is mainly the product of the transverse yield strength obtained from the test and the loading area, while the maximum clamping force F of the wooden component is calculated under the constraint of the lateral clamping force. Therefore, the maximum clamping force F of the wooden component is calculated based on the fact that the yield strength of the wood will increase by 80% when constrained in the circumferential direction.

[0131] After the components have been repaired and clamped for 24 hours, unloading is performed. The bolts and nuts are pre-tightened in the following order: first the upper and lower clamping assemblies 10, then the side clamping assemblies 20, and first the diagonal clamps, then the center clamps. The unloading process should not be too fast. Finally, the device is unloaded in the following order: side clamping assembly 20, bolts and nuts in the upper and lower clamping assemblies 10, first pair of clamping plates 11, and second pair of clamping plates 21.

[0132] Repair quality observation. Remove the wrapping release paper and the sealing release paper in sequence, and observe whether the crack is closed. If it is not closed, observe whether the adhesive completely fills the crack, and perform secondary filling if necessary. The surface of the component relative to the adhesive layer can be sanded with sandpaper and a sander.

[0133] Example 1:

[0134] Taking the Putaifang (a type of wooden beam) of Yingxian Wooden Pagoda as an example, the cross-sectional dimensions of the Putaifang are 37cm×18cm. During its long service life, the cross-sectional dimensions of the Putaifang changed to 38.5cm×19cm due to cracking and other reasons. There are no other components in direct contact within 1.5m of the length of the wooden component.

[0135] Before the repair began, the cracking conditions on the four sides of the wooden component were statistically analyzed, and the length, width, and height of each crack were measured. The amount of adhesive to be applied was calculated according to the above formula (7). The adhesive used for repair was a two-component silicone-modified epoxy resin adhesive. The adhesive was injected into the cracks of the wooden component using an applicator, and at the same time, the un-adhesive areas were evenly coated with a brush. After the adhesive was applied, the release paper was sealed with tape, and finally the specimen was completely wrapped with release paper.

[0136] After completing the above preliminary work, install the repair device provided in Embodiment 2. Specifically, install it according to the installation method provided in Embodiment 2. Based on the cross-sectional dimensions of the wooden component (38.5cm × 19cm), the repairable length of the wooden component is 1.5m. Therefore, the upper and lower clamping components 10 from the first type of repair device are selected. Three supplementary plates 211 are added and placed in the second pair of clamping plates 21 of the side plate clamping component. The supplementary plates 211 are then locked to the main clamping plate 210 using the second fastener 50. A total of four sets are used.

[0137] After the device setup was completed, pressure repair began. First, the upper and lower clamping assemblies 10 were pre-tightened sequentially, with the middle bolts installed first, followed by the four diagonal bolts. Next, the four bolts and nuts of the side plate clamping assembly were tightened sequentially, with the force applied to each bolt calculated as 85.68 kN according to formula (8). Then, the six bolts of the upper and lower clamping assemblies 10 were tightened sequentially, with the middle bolts installed first, followed by the four diagonal bolts. The force applied to each bolt was calculated as 163.2 kN according to formula (9). Finally, it was checked that the force applied to each bolt met the required level, thus concluding the clamping repair process.

[0138]

[0139]

[0140] After the components have been repaired and clamped for 24 hours, they are unloaded. The bolts and nuts are pre-tightened in the following order: first the upper and lower clamping assemblies 10, then the side clamping plates, and first the diagonal clamps, then the center clamps. The unloading process should not be too fast. Finally, the device is unloaded in the following order: side clamping assembly 20, bolts and nuts in the upper and lower clamping assemblies 10, first pair of clamping plates 11, and second pair of clamping plates 21.

[0141] Repair quality observation. Remove the outer release paper and the sealing release paper in sequence, and observe whether the crack has closed. If it has not closed, observe whether the adhesive has completely filled the crack, and re-filling can be performed as needed. The surface of the wooden component relative to the adhesive layer can be sanded with sandpaper and a sander.

[0142] Example 2:

[0143] Taking the purlin of Yingxian Wooden Pagoda as an example, the cross-sectional dimensions of the purlin are 25.8cm×17.5cm. During its long service life, the cross-sectional dimensions of the purlin have changed to 27cm×18.5cm due to cracking, shelling and other reasons. There are no other components in direct contact within 1.2m of the length of the wooden component.

[0144] Before the repair began, the cracking conditions on the four sides of the component were statistically analyzed, and the length, width, and height of each crack were measured. The amount of adhesive to be applied was calculated according to the above formula (7). The adhesive used for repair was a two-component silicone-modified epoxy resin adhesive. The adhesive was injected into the cracks of the wooden component using an applicator, and at the same time, the un-adhesive areas were evenly coated with a brush. After the adhesive was applied, the release paper was sealed with tape, and finally the specimen was completely wrapped with release paper.

[0145] After completing the above preliminary work, install the repair device provided in Embodiment 2. Specifically, install it according to the installation method provided in Embodiment 2. Based on the component's cross-sectional dimensions of 25.8cm × 18.5cm, the repairable length of the wooden component is 1.2m. Therefore, the upper and lower clamping components 10 from the first type of repair device are selected. Two supplementary plates 211 are added and placed in the second pair of clamping plates 21 of the side plate clamping component. The supplementary plates 211 are then locked to the main clamping plate 210 using the second fastener 50. A total of three sets are used.

[0146] After the device setup was completed, pressure repair began. First, the upper and lower clamping plates were pre-tightened sequentially, with the middle bolts installed first, followed by the four diagonal bolts, to restore some of the component height. Next, the four bolts and nuts on the side clamping plates were tightened in a diagonal sequence, with each bolt applying a force of 71.4 kN, calculated using formula (8). Then, the six bolts on the upper and lower clamping plates were tightened sequentially, with the middle bolts installed first, followed by the four diagonal bolts, with each bolt applying a force calculated using formula (9), resulting in 106.1 kN per bolt. Finally, it was checked that the applied force to each bolt met the required strength, thus concluding the clamping repair process.

[0147]

[0148]

[0149] After the components have been repaired and clamped for 24 hours, they are unloaded. The bolts and nuts are pre-tightened in the following order: first the upper and lower clamping assemblies 10, then the side clamping plates, and first the diagonal clamps, then the center clamps. The unloading process should not be too fast. Finally, the device is unloaded in the following order: side clamping assembly 20, bolts and nuts in the upper and lower clamping assemblies 10, first pair of clamping plates 11, and second pair of clamping plates 21.

[0150] Repair quality observation. Remove the wrapping release paper and the sealing release paper in sequence, and observe whether the crack is closed. If it is not closed, observe whether the adhesive completely fills the crack, and perform secondary filling if necessary. The surface of the component relative to the adhesive layer can be sanded with sandpaper and a sander.

[0151] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0152] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A method for repairing transversely damaged wooden components, characterized in that, include: S100: Obtain the transverse yield strength required for repairing transversely damaged wooden components, and determine the maximum clamping force required for repairing transversely damaged wooden components based on the transverse yield strength; S200: Select the repair device according to the maximum clamping force, and then determine the number of the repair devices and the amount of adhesive to be injected according to the size information and cross grain feature information of the transversely damaged wooden component. S300: Apply glue to the damaged area of ​​the transversely damaged wooden component according to the glue amount, and then install the repair device in the damaged area according to the maximum clamping force to clamp and fix the transversely damaged wooden component. S400: After waiting for a preset time, remove the repair device and remove the adhesive layer remaining on the surface of the transversely damaged wooden component; The transverse yield strength required for repairing transversely damaged wooden components in step S100 includes: S110: Establish a model of a transversely intact wooden component of the original size based on the damaged area of ​​the transversely damaged wooden component; S120: The middle part of the transversely intact wooden component model is locally compressed to measure the compressive strength of the transversely intact wooden component model and construct a displacement-load curve. S130: Determine the transverse yield strength of the transversely intact wooden component model based on the displacement load curve, and use the transverse yield strength as the repair standard when repairing the transversely damaged wooden component. In step S100, determining the maximum clamping force required for repairing the transversely damaged wooden component based on the transverse yield strength includes: S140: The yield strength of wood under circumferential constraint increased by 50%-80% as measured by flawless small samples; S150: Determine the maximum clamping force required for repairing the transversely damaged wooden component, based on the fact that the yield strength of the wood will increase by 80% under circumferential constraint. The transverse grain feature information of the transversely damaged wooden component in step S200 includes the crack location, average crack width, and length and depth. The formula for calculating the amount of adhesive to be injected is as follows: The above The mass of the adhesive used during injection is given; each crack is assumed to have an inverted triangular cross-section, with the surface cracking being the most extensive and gradually decreasing towards the inside, so the injection volume is calculated as a triangular prism; L, W, and H are the length, width, and depth of the crack, respectively; The density of the adhesive used.

2. The method for repairing transversely damaged wooden components according to claim 1, characterized in that, Step S130 includes: S131: Based on the constructed displacement-load curve, the yield point of the transversely intact wooden component model is determined using the offset yield method; S132: Calculate the transverse yield strength of the transversely intact wooden component model based on the yield point; The formula for calculating the transverse yield strength is as follows: The compression area of ​​the transversely intact wooden component model is given. The yield load corresponding to the yield point. The yield strength is the value corresponding to the yield point.

3. The method for repairing transversely damaged wooden components according to claim 1, characterized in that, The repair device in step S200 includes an upper and lower clamping assembly and a side clamping assembly, which are connected by a plurality of first fasteners. The first fastener that meets the clamping requirements is selected from the upper and lower clamping assemblies and the side clamping assembly according to the maximum clamping force. Define the maximum clamping force as F, and the number of first fasteners in the upper and lower clamping assemblies as N. Calculate the force that each first fastener needs to withstand. : Among them, the maximum load-bearing capacity of the selected first fastener , The effective area of ​​the cross-section of the first fastener. This represents the maximum working strength of the first fastener; This represents the maximum load-bearing capacity of the first fastener.

4. The method for repairing transversely damaged wooden components according to claim 1, characterized in that, Before installing the repair device in step S300, the following is also included: S310: After completing the glue application, use a brush to spread the glue evenly and then seal the release paper at the glue application position with tape. S320: Then, use release paper to completely wrap the damaged area, and then install the repair device.

5. The method for repairing transversely damaged wooden components according to claim 1, characterized in that, Step S400 also includes observing the repair quality after removing the repair device, and observing whether the cracks in the damaged area are closed; if they are not closed, secondary filling is performed as appropriate.

6. A repair device for transversely damaged wooden components, characterized in that, The method for repairing transversely damaged wooden components according to any one of claims 1-5, wherein the repair device for the transversely damaged wooden components comprises: The upper and lower clamping assembly includes two first pair of clamping plates aligned along a first direction; and The side clamping assembly includes two second pair of clamping plates aligned along a second direction; Wherein, the first direction and the second direction are perpendicular to each other, the two first pairs of clamping plates and the two second pairs of clamping plates are respectively connected by a plurality of first fasteners, and buffer pads are provided on the opposite side of the two first pairs of clamping plates and the opposite side of the two second pairs of clamping plates.

7. The repair device for transversely damaged wooden components according to claim 6, characterized in that, Each of the first pair of clamping plates is provided with a plurality of elongated holes along the second direction for installing the first fastener, the length direction of the elongated holes being consistent with the second direction; and / or Each of the second pair of clamps includes two main clamps spliced ​​along the second direction, with a supplementary plate installed between the two main clamps, and the main clamps and the supplementary plate are connected by a second fastener.

Images