A beam-column node for a multi-story wood / bamboo frame structure
Through the connection between box steel columns and U-channel steel and steel hoops, the problem of insufficient node stiffness of multiple high-rise wood/bamboo frame structures is solved, the lateral force and stability are enhanced, and the efficient utilization and seismic performance of wood/bamboo is achieved. Improvement.
Patent Information
- Application Number
- CN201910143811.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2019-02-27
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2039-02-27
AI Technical Summary
The beam and column node stiffness of the multi-story wood/bamboo frame structure is relatively small, causing the horizontal grains of wood/bamboo beam and column to be compressed and creep, affecting the structure's lateral force and stability.
Box steel columns are used to connect wooden/bamboo frame beams and columns with U-shaped channel steel and steel hoops. Semi-rigid connection is achieved through upper and lower pins and beam joints, increasing the lateral stiffness and energy consumption capacity of the nodes, sharing bending moment and shearing Strength to avoid brittle damage of wood/bamboo.
It significantly improves the lateral stiffness and energy consumption capacity of the nodes, enhances the stability and seismic resistance of the structure, makes full use of the strength of wood/bamboo, reduces construction costs and processes, and meets the development needs of multiple high-rise wood/bamboo structures. .
Smart Images
Figure CN109723151B_ABST
Abstract
Description
Technical Field
[0001] This patent relates to the field of structural building materials technology and provides a beam-column node for a multi-story wood / bamboo frame structure, aiming to overcome the defects of the existing technology in the beam-column node of a multi-story wood / bamboo frame structure, such as low stiffness, transverse compression and creep of the wood / bamboo beams and columns. Background Art
[0002] Building structure (referred to as structure) refers to a spatial force system made of building materials in a building (including structures) that is used to bear various loads or effects and acts as a skeleton. Building structures can be divided into concrete structures, masonry structures, steel structures, light steel structures, wooden structures and composite structures, depending on the building materials used.
[0003] Building components (referred to as components for short) are parts that bear the load of the building and ensure the safety of the building structure, such as load-bearing walls, columns, floor slabs, roof trusses, stairs, foundations, etc.
[0004] The building frame (abbreviated as frame) is a statically determinate or statically indeterminate plane or space system composed of various rods connected by nodes.
[0005] The stiffness of the frame depends on the stiffness of the components and nodes themselves. The design of the structural nodes is a key factor in the amount of earthquake energy absorbed by the structure. At the same time, the nodes are the basis for the stability and energy consumption of the structure, and are also the foundation for the shaping of the shape.
[0006] The breakthroughs in the structural system of wood / bamboo buildings are inseparable from the node method. Wood / bamboo is not weldable like steel, nor can it be connected by pouring and anchoring steel bars like concrete. The connection and calculation methods of wood / bamboo structures are very different from those of other materials. If the final failure of the wood / bamboo structure occurs at the node, the material strength of the component cannot be fully utilized, and the reliability of the wood / bamboo structure itself is also affected.
[0007] With the policy promotion of prefabricated buildings and the release of the national standard "Technical Standards for Multi-story Wood Structure Buildings", the development potential of wood / bamboo structure buildings in China is growing. Multi-story wood / bamboo structure buildings can not only reduce greenhouse gas emissions, but also meet the housing needs of densely populated cities, and are one of the important strategies for urban development. However, the development of multi-story wood / bamboo structures is currently constrained by some engineering and technical issues, including low node stiffness and the need to optimize force transmission at the nodes.
[0008] In multi-story buildings, wind loads and earthquakes gradually play a controlling role as the height increases. At this time, the focus of the structure is the horizontal lateral force resistance system. The nodes of low-rise wood / bamboo structure buildings generally use steel plates with bolts, pins, or special connectors and other steel connectors. However, the lateral stiffness of these nodes is insufficient for the horizontal lateral resistance requirements of multi-story wood / bamboo structure buildings. At the same time, for multi-story wood / bamboo structure frame systems, due to the large accumulated gravity load on the bottom floor, transverse compression will occur between beams and columns, and wood / bamboo beams and columns and wood / bamboo floor slabs will also have the problem of transverse creep under long-term loads. These problems have restricted the development of multi-story wood / bamboo structure buildings. Summary of the invention
[0009] The purpose of this patent is to provide a beam-column node for a multi-story wood / bamboo frame structure, aiming to overcome the defects of the existing technology in the beam-column node of the multi-story wood / bamboo frame structure, such as low stiffness, compression and creep of the transverse grain of the wood / bamboo beams and columns. The node has high stiffness, a safe and reasonable force transmission path, and fully utilizes the strength of wood (bamboo) materials, improves the force-bearing performance of wood (bamboo) frame columns / beams, avoids brittle failure of beam-column components, increases the ductility of the structure, enables the structural components and nodes to give full play to the material properties, and also has better seismic resistance.
[0010] The purpose of this patent is achieved through the following technical solutions:
[0011] A beam-column node for a multi-story wood / bamboo frame structure, the node comprises a box-type steel column, the upper and lower wood / bamboo frame columns are connected to the steel column by pins and bolts fixed to the upper and lower parts of the steel column, and the wood / bamboo frame beam is connected to the steel column by U-shaped channel steel fixed to both sides of the steel column and steel hoops for tightening.
[0012] The effects of this patent are:
[0013] This patent provides a beam-column node for multi-story wood (bamboo) frame structures. The steel column of the node serves as the core force-bearing component, and can cooperate with the welded side channel steel, top and bottom hole rod system to significantly increase the lateral stiffness and energy dissipation capacity of the node. The increase in node stiffness increases the node bending moment transmission. On the one hand, this limits the rotation of the node hinge and increases the overall stability of the structure; on the other hand, it effectively reduces the maximum bending moment in the span of the component, and beams with the same cross-sectional size can have a larger span, which meets the development requirements of multi-story wood (bamboo) structures. The steel node device ensures that the force transmission path at the node is safe and reasonable. The channel steel and steel hoop avoid the loss of strength and cracking of the beam end caused by the opening of the wood (bamboo) frame beam end, and the integrity of the structure is better. The upper load is directly transferred to the steel column, which is then transferred to the lower frame column, avoiding the additional pressure of the wood (bamboo) frame beam and alleviating the influence of the creep of the transverse grain of the wood (bamboo) frame beam on the strength of the node; the increase of the node stiffness will increase its bending moment, and the channel steel and steel hoop make the transverse grain of the wood (bamboo) frame beam end compressed, share the effect of the end bending moment, offset the adverse effect of the increase of the bending moment, and make full use of the strength of the wood (bamboo) material; the side channel steel supports the wood (bamboo) frame beam, and directly transfers the bending moment and shear force to the steel column, which is then transferred to the lower wood (bamboo) frame column in the form of vertical load, reducing the bending moment of the wood (bamboo) frame column and improving the force performance of the wood (bamboo) frame column. The node device can be fully prefabricated in the factory, and the on-site construction and assembly are convenient and efficient, which reduces the cost and construction process. The node force transmission is reasonable, clear, safe and reliable, which meets the current development needs of assembled multi-story wood structures. This patent provides technical guarantee for the further development of multi-story wood (bamboo) structures.
[0014] The function of the upper pin connection is to connect the upper frame column with the node and transfer the axial force of the upper frame column to the node. The function of the lower pin connection is to connect the lower frame column with the node and evenly distribute the axial force of the node to the top of the lower frame column.
[0015] The function of the beam connector is to semi-rigidly connect the frame beam to the steel column and transfer the bending moment and shear force at the end of the frame beam to the beam connector.
[0016] The upper pin and the lower pin connect the upper and lower frame columns to the nodes through bolts, ensuring the connection strength of the upper and lower frame columns at the nodes; the vertical shear force and bending moment of the frame beam are transmitted to the beam connector, and the beam connector bears a certain shear force and bending moment to prevent the collapse of the frame beam under the action of a large dynamic load; the shear force and bending moment at the end of the frame beam are transmitted to the beam connector and the steel column to reduce the effect on the frame column. Under normal use, the above-mentioned multi-story wood / bamboo frame structure uses the beam-column node as a rigid node to connect the beams and columns into a frame that can resist lateral loads; under the action of an earthquake, the steel column, beam connector, upper pin, and lower pin consume the energy input of the earthquake through their own nonlinear deformation, and the deformation is concentrated on the steel column, avoiding the brittle failure of the wood / bamboo beam-column components, increasing the ductility of the structure, and allowing the structural components and nodes to give full play to the material properties, while also having better earthquake resistance.
[0017] As an improvement to this patent, the top surface of the steel column has the same shape and size as the cross-section of the upper wooden / bamboo frame column, and the bottom surface of the steel column has the same shape and size as the cross-section of the lower wooden / bamboo frame column, which is suitable for variable cross-sections of wooden / bamboo frame columns.
[0018] As a further improvement of the present patent, the pin fixedly connected to the upper part of the steel column extends into the end face of the upper wood / bamboo frame column connected to the steel column, and the pin fixedly connected to the lower part of the steel column extends into the end face of the lower wood / bamboo frame column connected to the steel column. A clearance groove is provided on the pin, and a spiral perpendicular to the pin passes through the upper and lower wood / bamboo frame columns and extends into the clearance groove.
[0019] As a further improvement of the present patent, a U-shaped channel steel for supporting one end of the wood / bamboo frame beam is fixedly connected to the side of the steel column, a steel plate is fixedly connected to both sides of the channel steel, and a steel hoop for fastening the wood / bamboo frame beam to the channel steel is set on the steel plate.
[0020] The channel width of the channel steel is equal to the width of the frame beam; external threads are set at both ends of the steel hoop, holes are opened on the steel plate, and the two ends of the steel hoop pass through the holes fixed on the steel plates on both sides of the channel steel, and are connected to the nuts with threaded pairs.
[0021] The steel column is made of steel with high strength and elastic modulus. This node is easy to prefabricate and standardize in the factory, and can meet the requirements of prefabricated buildings. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a schematic diagram of the beam-column node structure for multi-story wood / bamboo frame structures;
[0023] Figure 2 It is a schematic diagram of the decomposition of the beam-column node structure for multi-story wood / bamboo frame structures;
[0024] Figure 3 It is a schematic diagram of the connection between beam-column components and nodes. DETAILED DESCRIPTION
[0025] The following is a further description of this patent in conjunction with the accompanying drawings:
[0026] See also Figure 1 , Figure 2 , Figure 3 The beam-column node for a multi-story wood / bamboo frame structure shown in the figure includes a box-shaped steel column 1, an upper pin 5 vertically welded to the top surface of the steel column 1 and used in conjunction with a bolt 12 to connect an upper frame column 7 to the steel column 1, a lower pin 6 vertically welded to the bottom surface of the steel column 1 and used in conjunction with the bolt 12 to connect a lower frame column 8 to the steel column 1, and a beam connector 10 fixedly connected to the side surface of the steel column 1 and used to semi-rigidly connect a frame beam 9 to the steel column 1.
[0027] The steel column 1 is a closed box-type structure. The top surface of the steel column 1 has the same shape and size as the cross section of the upper frame column 7 , and the bottom surface of the steel column 1 has the same shape and size as the cross section of the lower frame column 8 .
[0028] In the prior art, the cross-sections of the upper frame column 7 and the lower frame column 8 are mostly circular and rectangular, among which the rectangular cross-sections are mostly square. Since the sizes of the upper frame column 7 and the lower frame column 8 can be the same or different, the steel column 1 can be a truncated cone structure or a prism structure. In the figure, the top and bottom surfaces of the steel column 1 are both square, and the steel column 1 is a regular quadrangular prism structure.
[0029] A plurality of pins are welded on the top and bottom surfaces of the steel column 1 , respectively. The pins located on the top surface of the steel column 1 are upper pins 5 , and the pins located on the bottom surface of the steel column 1 are lower pins 6 .
[0030] The main structure of the upper pin 5 and the lower pin 6 is cylindrical, and a clearance groove 501 is provided on the upper pin 5 and the lower pin 6. The clearance groove 501 is an annular groove, which is used to clamp or partially clamp the bolt 12 passing through the upper frame column 7 and the lower frame column 8 to connect the upper frame column 7 and the lower frame column 8 with the node.
[0031] In a specific implementation, the bolts 12 are usually arranged in a spatially staggered manner, so the clearance grooves 501 of the upper pins 5 on a steel column 1 that are located on a straight line are also located on a straight line.
[0032] The upper pins 5 are evenly distributed on the top surface of the steel column 1, and the lower pins 6 are evenly distributed on the bottom surface of the steel column 1. The number of the upper pins 5 and the lower pins 6 can be the same or different. In this example, the number of the upper pins 5 and the lower pins 6 is the same (four).
[0033] The beam connector 10 includes a channel steel 2 horizontally welded to the side of the steel column 1 for supporting the frame beam 9, a steel plate 3 fixed to both sides of the channel steel 2, and a steel hoop 4 arranged on the steel plate 3 for fastening the frame beam 9 in the channel steel 2.
[0034] The channel depth of the channel steel 2 is less than the height of the frame beam 9. In the figure, the channel depth of the channel steel 2 is half the height of the frame beam 9, and the channel width of the channel steel 2 is equal to the width of the frame beam 9. The steel profile is bent 90° at two locations with a length equal to the spacing between the outer side surfaces of the channel steel 2 and then extended in the same direction to form a steel hoop 4. External threads are set at both ends of the steel hoop 4, and a light hole 301 is opened on the steel plate 3. The two ends of the steel hoop 4 are respectively set in the light holes 301 on the steel plates 3 on both sides of the channel steel 2, and the nuts 11 are connected with threaded pairs below the light holes 301.
[0035] For aesthetic reasons and to meet the need for wrench space, the bottom surface of the steel plate 3 is flush with the bottom surface of the channel steel 2.
[0036] For reliable connection, 2-4 steel hoops 4 are generally used and evenly distributed on the steel plate 3, and the steel hoops 4 are parallel to the cross section of the channel steel 2. In this example, 2 steel hoops 4 are selected to cooperate with each channel steel.
[0037] There are many types of steel profiles for making the steel hoop 4, and two types of steel profiles are commonly used: wire and strip.
[0038] When selecting wire, external threads can be directly set after the wire is bent.
[0039] When the strip is used, after the strip is bent, studs (not shown in the figure) are fixed to both ends of the strip.
[0040] In this example, the profile material for making the steel hoop 4 is wire material.
[0041] The beam connector 10 corresponds to the frame beam 9 to be connected, that is, the channel width of the channel steel 2 at a node can be the same or different, and there can be one or more beam connectors 10 at a node; in addition, there can be multiple spatial positional relationships between the channel steel 2 and the steel column 1 at a node, that is, whether the two are perpendicular or not is determined by the spatial positional relationship of the frame beam 9 relative to the steel column 1. In this example, there are two identical beam connectors 10 arranged relatively, and the channel steel 2 is perpendicular to the steel column 1.
[0042] When the above multi-story wood / bamboo frame structure is connected with beam-column components by beam-column nodes:
[0043] The upper pin 5 holds the bolt 12 passing through the upper frame column 7 through the clearance groove 501 to form an upper pin connection with the upper frame column 7; the lower pin 6 holds the bolt 12 passing through the lower frame column 8 through the clearance groove 501 to form a lower pin connection with the lower frame column 8.
[0044] The end of the frame beam 9 is implanted into the channel steel 2 , the steel hoop 4 is installed, and the nut 11 is tightened to lock the frame beam 9 in the channel steel 2 .
[0045] This node has high stiffness, strength and ductility, and has a certain energy dissipation capacity under strong earthquakes. The function of the upper pin connection is to connect the upper frame column 7 with the node and transfer the axial force of the upper frame column 7 to the node. The function of the lower pin connection is to connect the lower frame column 8 with the node and evenly distribute the axial force of the node at the top of the lower frame column 8.
[0046] The functions of the channel steel 2 , the steel plate 3 and the steel hoop 4 are to connect and fix the frame beam 9 , and to transfer the bending moment and shear force at the end of the frame beam 9 to the channel steel 2 .
[0047] The upper pin 5 and the lower pin 6 connect the upper frame column 7 and the lower frame column 8 to the node through bolts, ensuring the connection strength of the upper frame column 7 and the lower frame column 8 at the node; the axial force of the upper frame column 7 is transmitted to the steel column 1 through the upper pin connection, and the axial force is transmitted to the frame column 8 through the lower pin connection, and is transmitted to the foundation. At the same time, the bolts are positioned at both ends of the column member, which has a beautiful appearance and convenient construction.
[0048] The vertical shear force and bending moment of the frame beam are transmitted to the channel steel 2 through the steel hoop 4. The channel steel 2 bears a certain shear force and bending moment, reducing the force on the steel hoop 4, and at the same time avoiding the collapse of the frame beam 9 under the action of a large dynamic load on the structure; the shear force and bending moment at the end of the frame beam 9 are transmitted to the channel steel 2 and the steel column 1, reducing the effect on the frame column. Under normal use, the steel column 1, the channel steel 2, the steel plate 3, the upper pin, and the lower pin form a rigid node, connecting the beam and the column into a frame that can resist lateral loads; under the action of an earthquake, the steel column 1, the channel steel 2, the steel plate 3, the upper pin, and the lower pin consume the energy input of the earthquake through their own nonlinear deformation, and most of the deformation can be concentrated on the steel column 1, avoiding the brittle failure of the beam and column components, increasing the ductility of the structure, and enabling the structural components and nodes to give full play to the material properties, while also having better earthquake resistance.
[0049] The beneficial effects of this patent are:
[0050] 1. Steel columns are used to replace the wooden columns at the original nodes, which increases the lateral stiffness of the nodes, solves the problem of insufficient lateral stiffness of the nodes of multi-story wood / bamboo frame structures, and makes full use of the mechanical properties of the materials.
[0051] 2. Increase node bending moment transmission through rigid nodes, enhance structural stability, effectively reduce the maximum bending moment in the beam span, increase the span of beams of the same size, and meet the development requirements of multi-story wood / bamboo buildings.
[0052] 3. Through steel hoops and channel steels, the transverse lines at the ends of the beams are compressed to share the effect of the increased bending moment, making full use of the material strength to offset the adverse effects of the increased bending moment caused by the increased node stiffness.
[0053] 4. The node device can be prefabricated in the factory, which is convenient for controlling the quality of the node. During construction, it only needs to be assembled on site, which improves construction efficiency and quality and reduces costs.
[0054] 5. By rationally designing the form of the nodes and the number of bolts, controlling the bearing capacity and deformation of the nodes, making the nodes and components work together, ensuring that the node force transmission path is safe and reasonable, and the integrity of the structure is better.
Claims
1. A beam-column node for a multi-story wood / bamboo frame structure, characterized in that: The node includes a box-shaped steel column, and the upper and lower wood / bamboo frame columns are connected to the steel column through pins and bolts fixed to the upper and lower parts of the steel column, and the wood / bamboo frame beam is connected to the steel column through U-shaped channel steel fixed to both sides of the steel column and steel hoops for fastening; The U-shaped channel steel used to support one end of the wood / bamboo frame beam is fixedly connected to the side of the steel column, and the steel plate is fixedly connected to both sides of the channel steel. The steel hoop used to fasten the wood / bamboo frame beam to the channel steel is set on the steel plate; the channel width of the channel steel is equal to the width of the frame beam; external threads are set at both ends of the steel hoop, and holes are opened on the steel plate. The two ends of the steel hoop pass through the holes fixed on the steel plates on both sides of the channel steel respectively, and are connected with nuts by threaded pairs; The top surface of the steel column has the same shape and size as the cross section of the upper wood / bamboo frame column, and the bottom surface of the steel column has the same shape and size as the cross section of the lower wood / bamboo frame column.
2. The beam-column node for multi-story wood / bamboo frame structure according to claim 1 is characterized in that: The pin fixedly connected to the upper part of the steel column extends into the end face of the upper wood / bamboo frame column connected to the steel column, and the pin fixedly connected to the lower part of the steel column extends into the end face of the lower wood / bamboo frame column connected to the steel column. A clearance groove is opened on the pin, and bolts perpendicular to the pin pass through the upper wood / bamboo frame column and the lower wood / bamboo frame column and extend into the clearance groove.
3. The beam-column node for multi-story wood / bamboo frame structure according to claim 1 is characterized in that: The steel columns are made of steel with high strength and elastic modulus.