Mortise and tenon wood structure reinforcing and repairing device and control method

Abstract

The invention relates to a tenon-and-mortise wood structure reinforcing and repairing device and a control method, the tenon-and-mortise wood structure reinforcing and repairing device is characterized in that anchorage devices are arranged at the two ends of prestressed pull rods, a plurality of laminated rigid blocks are arranged between wood beams and wood columns in the vertical space of a tenon-and-mortise wood structure in the height direction, and a plurality of prestressed pull rods are arranged in the rigid blocks; one end of each prestressed pull rod is fixed on a foundation beam or a ground beam of the existing building through an anchorage device, and the other end of each prestressed pull rod is fixed on a wood beam at the upper part through an anchorage device after sequentially penetrating through the rigid blocks upwards; the two sides of the rigid block body are connected with the original wooden columns of the mortise and tenon wood structure through tie bars respectively. The method is suitable for the endangered ancient building needing to be subjected to anti-seismic and wind-resistant reinforcement and repair, and the principle of repairing the old as the old can be met. Meanwhile, the invention also forms a novel structural system capable of improving the maximum applicable height of the modern antique wood structure building, and is suitable for modern antique wood structure high-rise buildings and structures developed based on the same technical principle.

Description

Technical Field

[0001] The present invention relates to the field of ancient building protection, reinforcement, and restoration, specifically to a device and control method for improving the seismic and wind resistance of mortise and tenon timber structures. The device is applicable to endangered ancient buildings requiring seismic and wind-resistant reinforcement and restoration, and meets the principle of "repairing the old as it was." The present invention also constitutes a novel structural system that can increase the maximum applicable height of modern antique-style timber structures, and is applicable to modern antique-style timber high-rise buildings and structures developed based on the same technical principles. Background Art

[0002] Most ancient buildings utilize mortise and tenon joint timber structures. Many are located in earthquake zones, on islands, or in areas with strong offshore winds. There is an urgent need for earthquake- and wind-resistant reinforcement and restoration of these endangered ancient buildings, adhering to the principle of "repairing the old as it was." Existing reinforcement and restoration technologies struggle to improve the structure's earthquake and wind resistance while effectively preventing changes to the building's appearance. Furthermore, the maximum height of traditional mortise and tenon joint timber structures is limited by their lateral stiffness and joint construction, making them inadequate for meeting the growing demand for height-replicating antique buildings. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, the present invention provides a device and control method for reinforcing and repairing mortise and tenon timber structures, suitable for reinforcing and repairing mortise and tenon timber structures for earthquake and wind resistance. The present invention arranges a certain number of rigid blocks at appropriate locations within the mortise and tenon timber structure, utilizing the sliding friction of the rigid blocks to dissipate earthquake and wind vibration energy, thereby improving the seismic and wind resistance of the mortise and tenon timber structure. The reinforcement and repair device can be decorated as a wall, ensuring that the reinforced and repaired structure retains the original architectural style.

[0004] The technical solution adopted in the present invention is: A device for reinforcing and repairing a mortise and tenon wooden structure comprises a rigid block, a prestressed tie rod and tie bars, and is characterized in that: anchors are provided at both ends of the prestressed tie rod, and a plurality of stacked rigid blocks are provided along the height direction between the wooden beams and wooden columns in the vertical space of the mortise and tenon wooden structure. A plurality of prestressed tie rods are arranged in the rigid blocks, one end of which is fixed to the foundation beam or ground beam of the existing building through the anchor, and the other end is fixed to the upper wooden beam (such as the roof or floor) through the anchor after passing through a plurality of rigid blocks in sequence. The two sides of the rigid block are respectively connected to the original wooden columns of the mortise and tenon wooden structure through tie bars.

[0005] The prestressed pull rod passes through a wooden beam protection piece provided on the wooden beam and is fixed to the wooden beam through an anchor. The wooden beam protection piece is a built-in sleeve covered with a steel plate.

[0006] One end of the tie bar is fixed to the rigid block, and the other end is fixed to the wooden column after passing through the arc-shaped steel strip (adapting to the shape of the wooden column to prevent stress concentration) and the wooden column protection piece in sequence. The wooden column protection piece is an internal sleeve covered with a steel plate.

[0007] The rigid blocks are made of prefabricated concrete blocks or hardwood products.

[0008] The contact surfaces between adjacent rigid blocks are artificially roughened or equipped with friction pads to improve energy dissipation; the remaining surfaces remain natural. The thickness of the rigid blocks is determined by the friction requirements of the adjacent contact surfaces and their inherent strength and stability. The contact surfaces between the rigid blocks and the beams and columns are natural surfaces without artificial intervention. The sliding friction interface formed by the contact surfaces of adjacent rigid blocks is called the energy dissipation joint.

[0009] The prestressed tie rods are precision-rolled threaded steel bars or prestressed steel strands. Anchors are provided at both ends of the prestressed tie rods, and connectors can be provided when the building is multi-story or the prestressed tie rods are long. When the prestressed tie rods pass through mortise and tenon wood structural members, protective measures (such as embedded sleeves, etc.) should be taken to prevent damage to the mortise and tenon wood structural members during tensioning. The core function of the prestressed tie rods is to control the positive pressure on the sliding contact surface by controlling the tensioning force, and to match the static friction threshold of the contact surface of adjacent rigid blocks with the seismic and wind resistance targets and energy consumption expectations.

[0010] A control method for a mortise and tenon wood structure reinforcement and repair device, characterized by being carried out in the following steps: Step 1, initial state setting; by tensioning the prestressed tie rods connecting the rigid blocks, a preset positive pressure is applied to the contact surfaces of adjacent rigid blocks, so that the contact surfaces of adjacent rigid blocks maintain a static friction state within the fortification load range; Step 2: Small load response—static friction locking mechanism: When the horizontal load is less than the static friction force on the contact surfaces of adjacent rigid blocks, the contact surfaces of the rigid blocks are in a static friction state, with no relative sliding. The rigid blocks form an integral wall structure, participating in the overall work through their own rigidity. At this point, the internal force of the mortise and tenon timber structure is below its damage threshold, and the structure remains elastic. Step 3: Overload triggers energy dissipation – critical state switching: When the horizontal load exceeds the static friction force on the contact surface of adjacent rigid blocks, the contact surface of the rigid blocks exceeds the static friction limit and enters a sliding friction state. The sliding friction force does work, forming a hysteretic energy dissipation mechanism: The sliding process generates a friction-type hysteretic energy dissipation curve, dissipating the input energy through repeated slip-reset cycles. Step 4, displacement control and structural protection - dual protection logic: Internal force unloading: Sliding friction limits the horizontal shear force transmitted to the mortise and tenon timber structure, preventing damage to the mortise and tenon timber structure.

[0011] Displacement limit: By adjusting the prestress of the prestressed tie rod to control the maximum friction force, the sliding displacement of the rigid block is indirectly constrained (a limit device can also be set to directly adjust the sliding displacement) to prevent the collapse of the mortise and tenon wooden structure.

[0012] Step 5: Reset after the load disappears - Self-reset capability: After the horizontal load disappears, the elastic restoring force of the prestressed rod pulls the rigid block back to its original position, and the contact surfaces of adjacent rigid blocks re-enter the static friction state.

[0013] Core working principle: Adjustable friction threshold: The tensioning force of the prestressed tie rod 1 directly controls the positive pressure of the contact surface, enabling precise design of the sliding trigger threshold to adapt to different defense requirements.

[0014] Dual-state performance switching: Rigid state (static friction): provides general structural stiffness; Energy dissipation state (sliding friction): The dynamic response of the wooden structure is significantly reduced by dissipating energy through friction hysteresis.

[0015] Protection priority: The sliding friction mechanism acts as a "structural fuse" (i.e., under strong earthquakes or strong winds, it absorbs and dissipates input energy through its own sliding movement, thereby protecting the mortise and tenon timber structure from damage), giving priority to consuming input energy to ensure that the internal force of the mortise and tenon timber structure is always at a safe level.

[0016] Hysteresis performance calibration: The hysteresis curve characteristics of the reinforcement and repair device (such as sliding stiffness and energy consumption efficiency) are calibrated through full-scale tests to ensure the consistency between the theoretical model and the actual response.

[0017] The present invention realizes the unity of passive structural control and adaptive energy consumption by intelligently adjusting the working state of the friction interface, and provides an effective hierarchical protection strategy for mortise and tenon wooden structures.

[0018] This invention proposes the concept of "organically combining rigid blocks with mortise and tenon timber structures." This concept is not only applicable to the restoration of historic buildings, but also constitutes a novel high-rise timber structure system. This system utilizes frictional energy dissipation to enhance the lateral stiffness and energy dissipation capacity of the mortise and tenon timber structure, thereby increasing the maximum applicable height of this structure. When the building plan is circular or rectangular, the rational arrangement of the rigid blocks 2 creates a tubular structure with energy dissipation devices.

[0019] The beneficial effects of the present invention are: 1. Improve the earthquake and wind resistance of mortise and tenon wooden structures.

[0020] 2. The device is arranged between beams and columns and can be decorated into a wall, so that the reinforced and repaired building is consistent with the original building style, in line with the principle of "repairing the old as it was".

[0021] 3. The principle of the energy dissipation mechanism between adjacent rigid blocks is clear, key parameters (friction coefficient, prestress) can be controlled through design, and the energy dissipation capacity can be verified through experiments, with high reliability.

[0022] 4. Protective measures should be taken to avoid damage to wooden structures.

[0023] 5. The construction is relatively simple and the materials are easily available. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic elevation view of the mortise and tenon wood structure reinforcement and repair device of the present invention.

[0025] Figure 2 for Figure 1 A_A cross-sectional view.

[0026] Figure 3 for Figure 1 B_B cross-sectional view. DETAILED DESCRIPTION

[0027] The present invention will be further described with reference to the accompanying drawings.

[0028] like Figure 1 、 Figure 2 、 Figure 3 As shown, the mortise and tenon wood structure reinforcement and repair device of the present invention includes a rigid block 2, a prestressed tie rod 1, and tie bars 7, and is characterized in that: anchors are provided at both ends of the prestressed tie rod 1, and a plurality of stacked rigid blocks 2 are provided along the height direction between the wooden beams 8 and wooden columns 9 in the vertical space of the mortise and tenon wood structure. A plurality of prestressed tie rods 1 are arranged in the rigid blocks 2, and one end of each prestressed tie rod 1 is fixed to the foundation beam 10 or ground beam of the existing building by an anchor, and the other end is fixed to the upper (roof or floor) wooden beam 8 by an anchor after passing through a plurality of rigid blocks 2 in sequence. Both sides of the rigid block 2 are connected to the wooden column 9 by tie bars 7. The prestressed tie rod 1 of the present invention is a precision-rolled threaded steel bar with anchors provided at both ends, and prestressed steel strands can also be used.

[0029] The prestressed tie rod 1 passes through the beam protector 4, which is a sleeve covered with steel plate, and is then secured to the beam 8 via an anchor. One end of the tie bar 7 is fixed to the rigid block 2, while the other end passes through a curved steel strip 6 (adapted to the shape of the column 9 to prevent stress concentration) and the column protector 5, which is a sleeve covered with steel plate, before being secured to the column 9. The rigid block 2 of the present invention is made of precast concrete blocks or hardwood products.

[0030] The contact surface between adjacent rigid blocks 2 is designed to be an artificial rough surface or to add friction plates to improve the energy dissipation capacity; the other surfaces remain in a natural state. The sliding friction interface formed by the contact surfaces of adjacent rigid blocks is called an energy dissipation joint 3. The thickness of the rigid block 2 is determined by the friction force requirements of the adjacent contact surfaces and its own strength and stability. By controlling the tension of the prestressed tie rod 1, the positive pressure on the adjacent contact surface of the rigid block 2 is controlled, so that when it encounters a load less than or equal to the design earthquake or set wind load, the contact surface maintains a static friction state, and its performance is similar to that of a general wall; when it encounters a load greater than the design earthquake or set wind load, the contact surface generates sliding friction, consumes the input energy, and protects the mortise and tenon wooden structure from damage through hysteresis energy dissipation, and controls its horizontal displacement to prevent collapse.

[0031] A control method for a mortise and tenon wood structure reinforcement and repair device, characterized by being carried out in the following steps: Step 1, initial state setting: by tensioning the prestressed tie rods connecting the rigid blocks, a preset positive pressure is applied to the contact surfaces of adjacent rigid blocks, so that the contact surfaces of adjacent rigid blocks maintain a static friction state within the fortification load range; Step 2: Small load response—static friction locking mechanism: When the horizontal load is less than the static friction force on the contact surfaces of adjacent rigid blocks, the contact surfaces of the rigid blocks are in a static friction state, with no relative sliding. The rigid blocks form an integral wall structure, participating in the overall work through their own rigidity. At this point, the internal force of the mortise and tenon timber structure is below its damage threshold, and the structure remains elastic. Step 3: Overload triggers energy dissipation – critical state switching: When the horizontal load exceeds the static friction force on the contact surface of adjacent rigid blocks, the contact surface of the rigid blocks exceeds the static friction limit and enters a sliding friction state. The sliding friction force does work, forming a hysteresis energy dissipation mechanism: the sliding process generates a friction-type hysteresis curve, dissipating the input energy through repeated slip-reset cycles. Step 4, displacement control and structural protection - dual protection logic: Internal force unloading: Sliding friction limits the horizontal shear force transmitted to the mortise and tenon timber structure, preventing damage to the mortise and tenon timber structure.

[0032] Displacement limit: By adjusting the prestress of the prestressed tie rod to control the maximum friction force, the sliding displacement of the rigid block is indirectly constrained (a limit device can also be set to directly adjust the sliding displacement) to prevent the collapse of the mortise and tenon wooden structure.

[0033] Step 5: Reset after the load disappears - Self-reset capability: After the horizontal load disappears, the elastic restoring force of the prestressed tie rod 1 pulls the rigid block back to its original position, and the contact surfaces of adjacent rigid blocks re-enter the static friction state.

[0034] Core working principle: Adjustable friction threshold: The tensioning force of the prestressed pull rod directly controls the positive pressure of the contact surface, realizing the precise design of the sliding trigger threshold to adapt to different defense requirements.

[0035] Dual-state performance switching: Rigid state (static friction): provides general structural stiffness; Energy dissipation state (sliding friction): The dynamic response of the wooden structure is significantly reduced by dissipating energy through friction hysteresis.

[0036] Protection priority: The sliding friction mechanism acts as a "structural fuse" that prioritizes the consumption of input energy, ensuring that the internal force of the mortise and tenon timber structure is always at a safe level.

[0037] Hysteresis performance calibration: The hysteresis curve characteristics of the reinforcement and repair device (such as sliding stiffness and energy consumption efficiency) are calibrated through full-scale tests to ensure the consistency between the theoretical model and the actual response.

[0038] The present invention realizes the unity of passive control and adaptive energy consumption by intelligently adjusting the working state of the friction interface, and provides an effective hierarchical protection strategy for the mortise and tenon wooden structure.

Claims

1. A device for reinforcing and repairing a mortise and tenon timber structure, comprising a rigid block, a prestressed tie rod, and tie bars, characterized in that: Anchors are provided at both ends of the prestressed tie rods. Several stacked rigid blocks are provided along the height direction between the wooden beams and wooden columns in the vertical space of the mortise and tenon wooden structure. Several prestressed tie rods are arranged in the rigid blocks. One end of each prestressed tie rod is fixed to the foundation beam or ground beam of the existing building through an anchor, and the other end passes through several rigid blocks in sequence upward and is fixed to the upper wooden beam through an anchor. Both sides of each rigid block are connected to the original wooden columns of the mortise and tenon wooden structure through tie bars.

2. The mortise and tenon wood structure reinforcement and repair device according to claim 1, characterized in that: The prestressed pull rod passes through a protective piece provided on the wooden beam and is fixed to the wooden beam through an anchor. The protective piece is a built-in sleeve covered with a steel plate.

3. The mortise and tenon wood structure reinforcement and repair device according to claim 1, characterized in that: One end of the tie bar is fixed to the rigid block, and the other end is fixed to the wooden column after passing through the arc-shaped steel plate strip and the protective piece provided on the wooden column in sequence. The protective piece is an internal sleeve covered with a steel plate.

4. The mortise and tenon wood structure reinforcement and repair device according to claim 1, characterized in that: The rigid blocks are made of prefabricated concrete blocks or hardwood products.

5. The mortise and tenon wood structure reinforcement and repair device according to claim 4, characterized in that: The contact surfaces between adjacent rigid blocks are designed to be artificially roughened or with additional friction plates; the remaining surfaces remain in a natural state.

6. The mortise and tenon wood structure reinforcement and repair device according to claim 1, characterized in that: The prestressed pull rod is a precision-rolled threaded steel bar or a prestressed steel strand.

7. A control method for the mortise and tenon wood structure reinforcement and repair device according to claim 1, characterized in that Follow these steps: Step 1, initial state setting: by tensioning the prestressed tie rods connecting the rigid blocks, a preset positive pressure is applied to the contact surfaces of adjacent rigid blocks, so that the contact surfaces of adjacent rigid blocks maintain a static friction state within the fortification load range; Step 2, small load response - static friction locking mechanism: When the horizontal load is less than the static friction force of the contact surface of the adjacent rigid blocks, the contact surface of the rigid blocks is in a static friction state and there is no relative sliding; Step 3: Overload triggers energy dissipation – critical state switching: When the horizontal load exceeds the static friction force on the contact surface of adjacent rigid blocks, the contact surface of the rigid blocks exceeds the static friction limit and enters a sliding friction state. The sliding friction force does work, forming a hysteresis energy dissipation mechanism: the sliding process generates a friction-type hysteresis curve, dissipating the input energy through repeated slip-reset cycles. Step 4, displacement control and structural protection - dual protection logic: Internal force unloading: Sliding friction limits the shear force transmitted to the mortise and tenon wood structure, avoiding damage to the mortise and tenon wood structure; Displacement limit: By adjusting the prestress of the prestressed tie rod to control the maximum friction force, the sliding displacement of the rigid block is indirectly constrained (a limit device can also be set to directly adjust the sliding displacement) to prevent the collapse of the mortise and tenon wooden structure; Step 5: Reset after the load disappears - Self-reset capability: After the horizontal load disappears, the elastic restoring force of the prestressed rod pulls the rigid block back to its original position, and the contact surfaces of adjacent rigid blocks re-enter the static friction state.

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