A traceless repairing device suitable for wood structure column and a construction method thereof

Abstract

The application provides a traceless repairing device for a wood structure column, which is used for being placed in a double-cone hollow at a connection between an existing wood structure column and a new wood structure column; the device comprises a center disc, a supporting leg, an upper disc, a lower disc, a limiting plate, a rotating shaft and a fixing leg; the upper disc, the center disc and the lower disc are sequentially arranged in the same way, and the diameters of the upper disc and the lower disc are smaller than that of the center disc; the fixing leg is rotationally symmetrically arranged along the circumferences of the upper disc and the lower disc, and the two ends of the supporting leg are rotationally connected with the center disc and the fixing leg through the rotating shaft; the outer side wall of the supporting leg is in a sawtooth structure; the limiting plates are arranged on the sides opposite to each other of the upper disc and the lower disc, and metal long nails for connecting the existing wood structure column and the new wood structure column are arranged on the limiting plates; a grouting air outlet hole is arranged on the existing wood structure column, and a grouting hole is arranged on the new wood structure column. The application also provides a construction method of the repairing device.

Description

Technical Field

[0001] This invention relates to a traceless repair device for wooden structural columns and its construction method. Background Technology

[0002] With urban development and the increasing prominence of aging historical buildings, the demand for the protection and restoration of ancient buildings, especially wooden structures, continues to grow. Traditional methods of large-scale demolition and reconstruction, involving extensive dismantling and rebuilding, are not only time-consuming and cause significant disturbance to the original structure, but also easily damage the historical appearance and cultural value. Therefore, minimally invasive restoration has become paramount. This involves restoring the building while preserving its original texture as much as possible, and avoiding the use of modern construction materials in its exterior design to maintain its historical character.

[0003] In ancient wooden structures, the base of wooden columns often rots due to long-term dampness and rainwater soaking. Traditional restoration techniques often employ a "beam-supported column replacement" method, which involves cutting off the base of the column, using tenon joints to join the old and new wooden columns together, and then reinforcing the structure with clamps.

[0004] However, repairing the building with clamps exposes the steel clamps and other materials, affecting the historical appearance of the ancient building. Furthermore, these materials can rust over time, creating potential quality issues. Summary of the Invention

[0005] The main technical problem to be solved by the present invention is to provide a traceless repair device and construction method for wooden structural columns, which can repair rotten wooden structural columns without affecting their appearance.

[0006] To solve the above-mentioned technical problems, the present invention provides a traceless repair device suitable for wooden structure columns. The repair device is used to be placed in a double-frustum cavity hollowed out at the connection between an existing wooden structure column and a new wooden structure column; it includes: a central disc, a support leg, an upper disc, a lower disc, a limiting plate, a rotating shaft, and a fixing leg.

[0007] The upper, central, and lower discs are arranged in the same manner, with the diameters of the upper and lower discs being smaller than that of the central disc. The fixed legs are arranged symmetrically around the circumference of the upper and lower discs. The two ends of the supporting legs are rotatably connected to the central disc and the fixed legs respectively via pivots. The outer sidewall of the supporting legs has a serrated structure. The limiting plates are respectively located on opposite sides of the upper and lower discs, and the limiting plates are provided with long metal nails for connecting the existing wooden structure column and the new wooden structure column.

[0008] The existing wooden structure columns are provided with grouting vent holes, and the new wooden structure columns are provided with grouting holes.

[0009] In a preferred embodiment: the repair device has an extended state and a retracted state, wherein the extended state refers to the position where the fixed leg extends radially along the upper or lower disk, and the retracted state refers to the position where the support leg extends axially parallel to the central disk.

[0010] In a preferred embodiment: when the repair device is in the unfolded state, the sum of the diameters of the upper or lower disc and the fixed leg is greater than the diameter of the central disc.

[0011] The present invention also provides a method for constructing the repair device as described above, comprising the following steps:

[0012] 1) Grind the joint surfaces of the existing and new wooden columns smooth to prepare for the joint;

[0013] 2) A frustum-shaped cavity is chiseled out at the center of the joint between the existing wooden column and the new wooden column;

[0014] 3) Drill grouting holes and grouting vent holes on the existing timber structure columns and the new timber structure columns respectively;

[0015] 4) Pull the upper and lower discs of the repair device away from each other, so that the repair device is in a retracted state and then placed into the frustum-shaped cavity;

[0016] 5) Move the new wooden column upwards so that the repair device can unfold inside the frustum-shaped cavity;

[0017] 6) Adjust the existing wooden structure columns and the new wooden structure columns to align them; after alignment, install the column piers and inject grout into the frustum-shaped cavity through the grouting holes until the grout flows out from the grouting vent holes.

[0018] In a preferred embodiment, the diameter of the grouting hole and the grouting vent hole is 1.5 cm.

[0019] In a preferred embodiment: the grouting hole is inclined upwards, and the grouting vent hole is inclined downwards.

[0020] In a preferred embodiment: the inner diameter of the frustum-shaped cavity is 10cm, the diameter of the opening is 5cm, and the depth is 15cm.

[0021] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0022] 1. Easy installation and simple operation: The device adopts a foldable four-bar structure design. When folded, it is compact in size and can be easily placed into a narrow frustum-shaped cavity without the need for complicated auxiliary positioning equipment. The device can be folded and unfolded by axial movement of the upper and lower discs. The construction process is simple, which can effectively reduce the difficulty of construction, improve the efficiency of construction, and reduce the labor intensity of construction personnel.

[0023] 2. Reliable fixation and strong stability: The serrated structure on the outside of the support leg forms a mechanical interlock with the inner wall of the frustum-shaped cavity. Combined with long metal nails, the device is rigidly connected to the old and new wooden structure columns, achieving double fixation. This can effectively prevent the device from axially slipping or rotating circumferentially during grouting. After the device is unfolded, the force is evenly distributed, and it can fit tightly against the inner wall of the cavity, ensuring the stability of the connection after repair.

[0024] 3. Dense grouting and good repair effect: The staggered design with upward-sloping grouting holes and downward-sloping grouting air outlets utilizes aerodynamic principles to smoothly expel air from the cavity during grouting, avoiding defects such as voids and gaps. This ensures that the grouting material fully fills the cavity, significantly improving the connection strength between new and old wooden columns and extending the service life of wooden structures.

[0025] 4. High versatility and wide adaptability: The dimensions of each component of the device (such as the diameter of the disc, the length of the support leg, and the number of fixed legs) can be adjusted according to the actual repair needs. It is suitable for the connection and repair of existing wooden columns and new wooden columns under various specifications and working conditions. There is no need to design special devices for different scenarios, which reduces repair costs and has a wide range of application prospects.

[0026] 5. High durability and long service life: All key components (fixed legs, support legs, metal spikes) are made of corrosion-resistant and high-strength materials such as stainless steel or hard alloy. The disc is treated with anti-corrosion, which can effectively resist the effects of environmental factors such as moisture and corrosion, extend the service life of the device, and ensure the long-term stability of the repair effect. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the repair device in a preferred embodiment of the present invention;

[0028] Figure 2 This is a detailed schematic diagram of the repair device in a preferred embodiment of the present invention;

[0029] Figures 3-8 This is a schematic diagram of the construction method of the repair device in a preferred embodiment of the present invention. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0031] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" 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 invention based on the specific circumstances.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] In the description of this embodiment, the terms "upper," "lower," "right," and "left," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0034] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings (in this document, the reference numerals are uniformly used to correspond to each component to facilitate understanding and implementation by those skilled in the art). It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0035] The repair device disclosed in this invention aims to solve technical problems such as insufficient connection strength at the joint between existing and new wooden structural columns, cumbersome repair construction, and incomplete grouting. Through the design of a foldable support structure, the device can be easily installed and reliably fixed. With the help of a reasonable grouting structure, it significantly improves the connection stability between old and new wooden structural columns and is suitable for column joint repair scenarios in various types of wooden structures.

[0036] The repair device 1 disclosed in this invention aims to solve technical problems such as insufficient connection strength at the joint between existing wooden column 2 and new wooden column 3, cumbersome repair construction, incomplete grouting, poor adaptability to processing errors, and impact on the building texture after repair. Through foldable support structure design, modular adaptation design, and combined load-bearing structure design, the repair device 1 can be conveniently installed, reliably fixed, and adapted to multiple specifications. With a reasonable grouting structure and concealed design, it significantly improves the connection stability and load-bearing performance between existing wooden column 2 and new wooden column 3, while preserving the existing building texture to the greatest extent. It is suitable for column joint repair scenarios in various wooden structures.

[0037] like Figures 1-8 As shown in the figure, this embodiment provides a traceless repair device 1 suitable for wooden structure columns, which is placed in a frustum-shaped cavity hollowed out at the connection between the existing wooden structure column 2 and the new wooden structure column 3. Its specific structure, working state and construction method are as follows:

[0038] The repair device 1 mainly consists of a central disc 1-1, a support leg 1-2, an upper disc 1-3, a lower disc 1-3, a limiting plate 1-4, a rotating shaft 1-5, and a fixing leg 1-6. These components work together to achieve the functions of retracting, unfolding, and fixing the repair device 1. It also incorporates advantages such as modular adaptability, tolerance to processing errors, self-locking, and combined force bearing. The specific connection relationships and structural features are as follows:

[0039] The upper disc 1-3, the central disc 1-1, and the lower disc 1-3 are coaxially arranged sequentially along the axial direction. All three are made of anti-corrosion treated hard solid wood or anti-corrosion composite board. The anti-corrosion treatment preferably adopts a vacuum pressure anti-corrosion process, which can effectively improve the anti-corrosion and moisture-proof performance of the discs, extend the service life of the repair device 1, and is suitable for repairing existing wooden structural columns 2 and new wooden structural columns 3 in humid environments. The thickness of all three is 1.5~2.0cm, which ensures structural strength while being compatible with the materials of existing wooden structural columns 2 and new wooden structural columns 3, avoiding stress loss caused by contact between different materials. Among them, the diameters of the upper disc 1-3 and the lower disc 1-3 are equal and smaller than the diameter of the central disc 1-1. Specifically, the diameter of the central disc 1-1 is set to 20cm, and the diameters of the upper disc 1-3 and the lower disc 1-3 are set to 12cm. This size design allows the repair device 1 to form an effective supporting force surface after unfolding, and at the same time facilitates its retraction and placement.

[0040] This repair device 1 adopts a modular design. Both the support legs 1-2 and the fixed legs 1-6 adopt a detachable standardized modular structure. By replacing the support legs 1-2 and the fixed legs 1-6 with different lengths, the repair and switching of existing wooden structure columns 2 and new wooden structure columns 3 with different diameters can be realized. There is no need to design a special repair device 1 for columns of different specifications, which greatly improves the versatility of the repair device 1 and reduces the repair cost.

[0041] The fixing legs 1-6 are long, rigid structures made of stainless steel to prevent corrosion from prolonged exposure to humid environments, which would affect the service life of the repair device 1. The number of fixing legs 1-6 is preferably 4 to 6, and can be flexibly selected based on the diameter of the existing wooden column 2 and the new wooden column 3. When the column diameter is large, 6 fixing legs 1-6 are used, arranged symmetrically at a 60° rotational angle along the circumference of the upper and lower discs 1-3. When the column diameter is moderate, 6 fixing legs 1-6 are used, arranged symmetrically at a 60° rotational angle along the circumference of the upper and lower discs 1-3 (i.e., the angle between adjacent fixing legs 1-6 is 60°). This arrangement ensures that the repair device 1 is evenly stressed after unfolding, preventing excessive local stress that could damage the inner wall of the cavity. One end of the fixed leg 1-6 is rotatably connected to the edge of the upper disc 1-3 / lower disc 1-3 via a pivot 1-5; the other end of the fixed leg 1-6 is rotatably connected to the support leg 1-2 via a pivot 1-5; wear-resistant pads can be added to the connection points of the support leg 1-2 with the central disc 1-1 and the fixed leg 1-6 to reduce the wear of the pivot 1-5, extend the service life of the repair device 1, and ensure that the support leg 1-2 can rotate flexibly to realize the folding and unfolding of the repair device 1.

[0042] The supporting leg 1-2 is made of the same stainless steel as the fixed leg 1-6. Its length is adapted to the depth and slope of the frustum-shaped cavity 300, ensuring that the repair device 1 can fit tightly against the inner wall of the cavity after it is unfolded. Both ends of the supporting leg 1-2 are provided with pivot holes, which are respectively connected to the edge of the central disk 1-1 and the end of the fixed leg 1-6 away from the upper disk 1-3 / lower disk 1-3 through pivot 1-5, thus forming a symmetrical four-bar linkage mechanism. The axial movement of the upper disk 1-3 and the lower disk 1-3 drives the supporting leg 1-2 to rotate around the pivot 1-5, realizing the switching between the two working states of the repair device 1.

[0043] The outer wall of the support leg 1-2 is integrally formed with a serrated structure 21. The serrated structure 21 can be made of hard alloy material, with a tooth height of 2~3mm and a tooth pitch of 4~6mm. The tooth tips are rounded to avoid sharp tooth tips scratching the inner wall of the cavity. When the support leg 1-2 has an L-shaped structure, the serrated structure 21 can be staggered (i.e., the positions of two adjacent serrations are staggered), which can further increase the friction with the inner wall of the cavity and improve the fixing effect. The limiting plate 1-4 has several mounting holes evenly distributed in its central area and circumference. Metal long nails 51 are inserted into the mounting holes. The metal long nails 51 are made of high-strength stainless steel, with a length of 8-10cm and a diameter of 0.8-1.0cm. They may have external threads on their surface. The mounting holes on the limiting plate 1-4 have internal threads that match the external threads. The metal long nails 51 are connected to the limiting plate 1-4 by threads. This connection method facilitates the disassembly and installation of the metal long nails. At the same time, the driving depth of the metal long nails 51 can be adjusted according to actual needs to adapt to existing wooden structure columns 2 and new wooden structure columns 3 of different thicknesses. This further enhances the fixing reliability of the repair device 1 to the existing wooden structure columns 2 and new wooden structure columns 3, and better offsets the adverse effects of processing errors.

[0044] The limiting plate 1-4 is a circular steel plate with a thickness of 0.8~1.0cm and a diameter slightly larger than the diameter of the upper disc 1-3 and the lower disc 1-3 (preferably 14cm). It is fixedly installed on the upper surface of the upper disc 1-3 and the lower surface of the lower disc 1-3 by countersunk bolts. The countersunk bolts can prevent the bolt heads from protruding and affecting the connection between the existing wooden structure column 2 and the new wooden structure column 3. This repair device 1, through the coordinated structural design of the upper disc 1-3, lower disc 1-3, limiting plate 1-4, and rotating shaft 1-5, forms an automatic locking mechanism. When the repair device 1 is unfolded until the support leg 1-2 is tightly engaged with the inner wall of the cavity, the upper disc 1-3, lower disc 1-3, support leg 1-2, and fixed leg 1-6 form a stable triangular support structure, realizing the self-locking of the repair device 1. This can effectively prevent the repair device 1 from not being fully unfolded in the existing wooden structure column 2 and the new wooden structure column 3. At the same time, this structural design also increases the processing margin for the existing wooden structure column 2 and the new wooden structure column 3, further increasing the allowable processing error, facilitating on-site construction operations, and improving construction efficiency.

[0045] Through the synergistic action of the serrated structure 21 on the support leg 1-2 and the metal nail 51 on the limiting plate 1-4, the main structure of the repair device 1 can be firmly fixed to the existing wooden structure column 2 and the new wooden structure column 3, effectively avoiding the installation failure of the repair device 1 due to processing errors. This allows for a processing error of 10mm in the joint surface and cavity of the existing wooden structure column 2 and the new wooden structure column 3, reducing the difficulty of construction and processing.

[0046] The existing wooden column 2 has grouting vent holes 4, and the new wooden column 3 has grouting holes 5. Both grouting holes 5 and grouting vent holes 4 are circular through holes with a uniform diameter of 1.5 cm. After the repair device 1 is completed, only two holes, grouting holes 5 and grouting vent holes 4, will remain on the existing wooden column 2 and the new wooden column 3. After construction, these two holes can be placed on the wall side of the existing wooden column 2 and the new wooden column 3, or they can be sealed and hidden using traditional wooden structure hole repair methods, so as to maintain the original texture of the existing wooden structure building to the greatest extent and avoid damage to the building's appearance during the repair process. The grouting holes 5 are inclined upwards at an angle of 30° to 45°. This angle allows the grout to flow smoothly into the frustum-shaped cavity 300 under gravity, while preventing backflow. The grouting vent holes 4 are inclined downwards at an angle of 30° to 45°. Their function is to expel air from the cavity during grouting, ensuring that the grout fully fills every corner of the cavity and preventing defects such as voids and gaps. This repair device 1 utilizes components such as the central disc 1-1, support legs 1-2, and fixed legs 1-6 to form a combined load-bearing structure with the grout. After the grout has cured, it is tightly integrated with the repair device 1 body, the existing wooden column 2, and the new wooden column 3, forming an integrated load-bearing system. This ensures that the existing wooden column 2 and the new wooden column 3 have sufficient strength to withstand horizontal forces after repair, significantly improving the lateral displacement resistance and overall stability at the connection between the existing wooden column 2 and the new wooden column 3. The grouting hole 5 is equipped with a grouting connector to facilitate the connection of grouting equipment; the grouting vent hole 4 is equipped with an exhaust valve to control the exhaust speed and prevent the grout from overflowing too quickly.

[0047] The repair device 1 has two working states: an unfolded state and a retracted state. Switching between these two states is achieved through the axial movement of the upper and lower discs 1-3, while also achieving self-locking based on its structural design. Specifically: In the retracted state, the upper and lower discs 1-3 are pulled away from each other. Under the pulling force, the support leg 1-2 rotates around the pivot 1-5, gradually extending along a direction parallel to the axial direction of the central disc 1-1. At this time, the radial dimension of the entire repair device 1 is minimized, and its maximum radial dimension is smaller than the diameter of the opening of the frustum-shaped cavity 300, facilitating the smooth insertion of the repair device 1 into the frustum-shaped cavity 300 and solving the problem of difficult placement. Furthermore, since the repair device 1 has a 10mm machining error tolerance, even slight deviations in the opening size of the frustum-shaped cavity 300 will not affect the smooth placement of the repair device 1. In the unfolded state, the lifting force on the upper disk 1-3 and the lower disk 1-3 is released. Under the pushing action of the new wooden structure column 3, the upper disk 1-3 and the lower disk 1-3 move towards each other, causing the support leg 1-2 to rotate around the pivot 1-5 away from the axis of the central disk 1-1, until the fixed leg 1-6 extends radially outward along the upper disk 1-3 or the lower disk 1-3. At this time, the repair device 1 is in the unfolded state. According to the limitation of claim 3, when the repair device 1 is in the unfolded state, the total radial dimension of the upper disk 1-3 or the lower disk 1-3 and the fixed leg 1-6 (i.e., the sum of the radius of the upper disk 1-3 / lower disk 1-3 and the length of the fixed leg 1-6) is greater than the diameter of the central disk 1-1, so that the serrated structure 21 on the outer side of the support leg 1-2 can tightly engage with the inner wall of the frustum-shaped cavity 300. Combined with the fixing action of the metal long nail 51, the repair device 1 is reliably fixed. Meanwhile, the structure consisting of the upper disc 1-3, the lower disc 1-3, the limiting plate 1-4, and the rotating shaft 1-5 achieves self-locking, ensuring that the repair device 1 will not be incompletely unfolded, further guaranteeing the reliability of the fixation. The modular design of the repair device 1 allows for quick replacement of the corresponding length of support leg 1-2 and fixing leg 1-6 if the diameter of the existing wooden structure column 2 or the new wooden structure column 3 on site does not match the preset size, without having to disassemble and reassemble the entire repair device 1, thus improving construction flexibility.

[0048] Based on the aforementioned repair device 1, the construction method specifically includes the following steps, each of which strictly follows the construction specifications. At the same time, it fully leverages the advantages of the repair device 1, such as its tolerance for processing errors, modular adaptability, and self-locking, to ensure both repair effectiveness and construction efficiency:

[0049] Step 1) Pre-treatment of the mating surface: First, the mating surfaces of the existing wooden column 2 and the new wooden column 3 are sanded. Sandpaper, a grinder, and other tools are used to remove burrs, rotten layers, stains, and dust from the mating surface, ensuring it is flat, clean, and free of loose impurities. After sanding, a blower is used to clean the debris from the mating surface, preparing it for mating. Since this repair device 1 allows for a 10mm error in the processing of the existing wooden column 2 and the new wooden column 3, it is not necessary to excessively pursue absolute flatness during the sanding process. The sanding precision requirement can be appropriately reduced to improve construction efficiency and avoid uneven mating surfaces that could lead to insufficient grouting filling and affect the connection strength.

[0050] Step 2) Carving a frustum-shaped cavity: At the center of the mating surface between the existing wooden column 2 and the new wooden column 3, a frustum-shaped cavity is carved out using a special chisel (such as an electric chisel or a hand chisel). As defined in claim 7, the internal diameter (large end diameter) of the frustum-shaped cavity is 10cm, the diameter at the opening (small end diameter) is 5cm, and the depth is 15cm. During the carving process, the slope of the cavity needs to be kept uniform. There is no need to excessively control the dimensional accuracy, because the repair device 1 has a 10mm machining error tolerance capability, and the structural design of the upper disc 1-3, lower disc 1-3, limiting plate 1-4, and rotating shaft 1-5 increases the machining allowance. Even if there is a slight deviation in the cavity size, it will not affect the installation and fixation of the repair device 1. After the carving is completed, the sawdust and debris inside the cavity are cleaned to ensure that the cavity is clean.

[0051] Step 3) Drilling: Using an electric drill, drill grouting vent holes 4 and grouting holes 5 on the existing wooden column 2 and the new wooden column 3, respectively. During drilling, the hole diameter must be strictly controlled to 1.5 cm, consistent with the limitation in claim 5. The grouting hole 5 is drilled on the side of the new wooden column 3, preferably on the side closest to the wall for easier concealment later. The grouting hole 5 is inclined upwards at 30°~45°, and the drilling depth must penetrate the side wall of the new wooden column 3 and connect with the frustum-shaped cavity. The grouting vent hole 4 is drilled on the side of the existing wooden column 2, again preferably on the side closest to the wall, inclined downwards at 30°~45°, and the drilling depth also penetrates the side wall of the existing wooden column 2 and connects with the frustum-shaped cavity. After drilling, clean the sawdust from the holes to ensure unobstructed passage, laying the foundation for subsequent grouting and venting, and preparing for subsequent concealment of the hole positions.

[0052] Step 4) Installation of the Repair Device: Based on the actual diameters of the existing wooden column 2 and the new wooden column 3, select support legs 1-2 and fixed legs 1-6 of suitable length. Assemble the repair device 1 using a modular replacement method, eliminating the need to redesign or process the main body of the repair device 1, thus improving construction flexibility and efficiency. Subsequently, the operator holds the edges of the upper and lower discs 1-3 and pulls them apart, switching the repair device 1 to the retracted state. Slowly place the retracted repair device 1 into the frustum-shaped cavity, adjusting its position so that the central disc 1-1 is located in the center of the frustum-shaped cavity, ensuring even force distribution on the repair device 1. Because the repair device 1 has a 10mm machining error tolerance, even with slight deviations in the cavity dimensions, the installation operation can be successfully completed.

[0053] Step 5) Deployment of the repair device: Slowly move the new wooden column 3 upwards, so that the mating surface of the new wooden column 3 gradually approaches the mating surface of the existing wooden column 2. At the same time, the pushing action of the new wooden column 3 on the upper limiting plate 1-4 drives the upper disc 1-3 to move downwards, so that the upper disc 1-3 and the lower disc 1-3 move towards each other, thereby driving the support leg 1-2 to rotate and unfold around the rotating shaft 1-5. Continue to move the new wooden column 3 until the serrated structure 21 on the outside of the support leg 1-2 is tightly engaged with the inner wall of the frustum-shaped cavity, and the repair device 1 can no longer move. At this time, the repair device 1 is fully deployed and reliably fixed. At the same time, the structure formed by the upper disc 1-3, the lower disc 1-3, the limiting plate 1-4 and the rotating shaft 1-5 achieves self-locking to avoid the repair device 1 not being fully deployed, ensuring the stability of subsequent grouting and stress. During this process, the metal nails 51 are gradually embedded into the existing wooden structure column 2 and the new wooden structure column 3, forming a double fixation with the serrated structure 21 on the support legs 1-2, which further improves the fixation reliability and at the same time offsets the adverse effects of processing errors.

[0054] Step 6) Alignment, Fixing, and Grouting: Adjust the positions of the existing wooden column 2 and the new wooden column 3 to align their axes and ensure tight contact between their mating surfaces, guaranteeing uniform stress on the columns. After alignment, install column piers on top of the new wooden column 3. The column piers should be made of materials and specifications matching the column body to support and fix the new wooden column 3, preventing displacement during grouting. Then, connect the grouting pipe of the grouting equipment to the grouting connector of the grouting hole 5, and inject grouting material under high pressure into the frustum-shaped cavity. The grouting material used is a high-strength wood structure-specific grouting material with good adhesion and strength. Continue grouting until the grout flows out evenly from the grouting vent hole 4, indicating that the frustum-shaped cavity has been completely filled with grouting material. Stop grouting at this point. Finally, seal the grouting hole 5 and the grouting vent hole 4 with sealing plugs. If the hole is not located on the wall side, traditional wood structure hole repair methods can be used to conceal the hole, preserving the existing building texture to the greatest extent possible. Once the grout has been cured to its design strength (curing time not less than 72 hours), the repair device 1 and the grout form a combined load-bearing structure, enabling the repaired existing wooden column 2 and the new wooden column 3 to have sufficient horizontal force bearing capacity.

[0055] After grouting is completed, the grouting holes 5 and grouting vent holes 4 are treated in the manner of installing wooden structure holes (after cleaning the holes, water-based repair putty is used for repair, and after completion, clear water paint is applied, with the paint color tinted to be similar to the wood), or the grouting holes can be set in advance at the wooden wall where they connect with the wooden structure column to hide them, thus completing the entire repair construction.

[0056] The above is only one specific embodiment of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantial modifications made to the present invention using this concept shall be deemed as infringing the protection scope of the present invention.

Claims

1. A traceless repair device suitable for wooden structural columns, characterized in that: The repair device is used to be placed in the double-frustum cavity hollowed out at the connection between the existing wooden structure column and the new wooden structure column; it includes: a central disc, a support leg, an upper disc, a lower disc, a limiting plate, a rotating shaft, and a fixing leg; The upper, central, and lower discs are arranged in the same manner, with the diameters of the upper and lower discs being smaller than that of the central disc. The fixed legs are arranged symmetrically around the circumference of the upper and lower discs. The two ends of the supporting legs are rotatably connected to the central disc and the fixed legs respectively via pivots. The outer sidewall of the supporting legs has a serrated structure. The limiting plates are respectively located on opposite sides of the upper and lower discs, and the limiting plates are provided with long metal nails for connecting the existing wooden structure column and the new wooden structure column. The existing wooden structure columns are provided with grouting vent holes, and the new wooden structure columns are provided with grouting holes.

2. The traceless repair device for wooden structure columns according to claim 1, characterized in that: The repair device has an extended state and a retracted state. The extended state refers to the position where the fixed leg extends radially along the upper or lower disc, and the retracted state refers to the position where the supporting leg extends axially parallel to the central disc.

3. The traceless repair device for wooden structural columns according to claim 2, characterized in that: When the repair device is in the unfolded state, the sum of the diameters of the upper or lower disc and the fixed leg is greater than the diameter of the central disc.

4. A method for constructing a repair device according to any one of claims 1-3, characterized in that... Includes the following steps: 1) Grind the joint surfaces of the existing and new wooden columns smooth to prepare for the joint; 2) A frustum-shaped cavity is chiseled out at the center of the joint between the existing wooden column and the new wooden column; 3) Drill grouting holes and grouting vent holes on the existing timber structure columns and the new timber structure columns respectively; 4) Pull the upper and lower discs of the repair device away from each other, so that the repair device is in a retracted state and then placed into the frustum-shaped cavity; 5) Move the new wooden column upwards so that the repair device can unfold inside the frustum-shaped cavity; 6) Adjust the existing timber structure columns and the new timber structure columns to align them; After alignment, install the column base and inject grout into the frustum-shaped cavity through the grouting hole until the grout flows out from the grouting vent hole.

5. The construction method of a traceless repair device for wooden columns according to claim 4, characterized in that: The diameter of the grouting hole and the grouting vent hole is 1.5 cm.

6. The construction method of the traceless repair device for wooden columns according to claim 4, characterized in that: The grouting holes are inclined upwards, and the grouting vent holes are inclined downwards.

7. The construction method of a traceless repair device for wooden columns according to claim 4, characterized in that: The frustum-shaped cavity has an internal diameter of 10cm, an opening diameter of 5cm, and a depth of 15cm.

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