Newly-added beam body steel structure joint based on existing column body and construction method

Abstract

The invention relates to the technical field of repairing, dismantling or other work of original buildings, and particularly discloses a newly-added beam body steel structure joint based on an existing column and a construction method.The newly-added beam body steel structure joint comprises an existing concrete frame column, a first anchoring part and a second anchoring part, and the existing concrete frame column is provided with four end faces; the first anchoring part penetrates through the existing concrete frame column, the first anchoring part is fixedly connected with two opposite end faces, the first anchoring part is fixedly connected with the newly-added steel beam and used for supporting the newly-added steel beam, the second anchoring part is fixedly connected with the other two opposite end faces, and the second anchoring part is fixedly connected with the first anchoring part and used for supporting the newly-added steel beam. The second anchoring part is used for improving the pulling resistance and the shearing resistance of the first anchoring part. The beam body steel structure node has the effect of improving the problem that the construction period of the newly-added beam body steel structure node of the existing column body is relatively long in the prior art.

Description

Technical Field

[0001] This application relates to the technical field of repairing, demolishing or otherwise working on existing buildings, and in particular to a method for constructing a new steel beam joint based on existing columns. Background Technology

[0002] As building functions are adjusted or equipment is upgraded, the original structure often cannot withstand the loads of new floor slabs, machine rooms, or pipelines. In this case, it is necessary to add beams to the existing concrete frame columns and reliably transfer the new loads to the existing columns by means of rebar or steel brackets, thereby expanding the space or increasing the load-bearing capacity without demolishing or altering the main structure.

[0003] However, existing methods for adding beams to existing concrete frame columns typically involve first drilling holes or chiseling out keyways on the side of the column, inserting threaded steel bars with adhesive anchors as ties, then erecting formwork, binding the beam reinforcement, and finally pouring concrete to form an integral joint between the new beam and the column. This process requires curing the concrete, resulting in a relatively long construction period. Summary of the Invention

[0004] To address the issue of long construction cycles for adding new beam-steel structure nodes to existing columns, this application provides a method for adding new beam-steel structure nodes to existing columns and a construction method thereof.

[0005] Firstly, this application provides a technical solution for adding a new beam steel structure node based on an existing column, using the following approach: A new beam-steel structure node based on existing columns, comprising: An existing concrete frame column is provided with a first end face, a second end face, a third end face and a fourth end face, wherein the first end face is opposite to the third end face and the second end face is opposite to the fourth end face; The first anchor is inserted through the existing concrete frame column. The first anchor is fixedly connected to the first end face and the third end face. The first anchor is also fixedly connected to the newly added steel beam to support the newly added steel beam. The second anchor is fixedly connected to the second end face and the fourth end face, and is also fixedly connected to the first anchor. The second anchor is used to improve the pull-out resistance and shear resistance of the first anchor.

[0006] By adopting the above technical solution, the existing reinforced concrete column, as the core load-bearing structural component, can provide a basic support frame, and its four end faces can provide connection nodes for the first and second anchors. The first anchor penetrates the existing reinforced concrete column, and its two ends are fixed to the first and third end faces of the column, while also connecting to the newly added steel beam, bearing and transferring the load of the steel beam to the existing reinforced concrete column. The second anchor is fixed to the second and fourth end faces of the existing reinforced concrete column and connects to the first anchor, forming a hoop constraint, which improves the pull-out and shear resistance of the first anchor. Specifically, the existing reinforced concrete column, the first anchor, and the second anchor form a spatial force system by adopting a combination of through anchoring and multi-directional end face constraint. Without the need for concrete curing strength, the rigid contact of the metal components directly improves the pull-out resistance and shear stiffness of the joint, thereby compressing the traditional seven to fourteen-day concrete curing period into approximately twenty-four hours of component installation time, improving the problem of the long construction period of the existing new beam steel structure joints in existing columns.

[0007] Preferably, the first anchor includes a first anchor plate, a second anchor plate, and a through bolt. The first anchor plate is fixedly connected to the first end face and the newly added steel beam. The second anchor plate is fixedly connected to the third end face. The through bolt passes through the existing concrete frame column, and its two ends are fixedly connected to the first anchor plate and the second anchor plate, respectively.

[0008] By adopting the above technical solution, the first anchor plate is fixedly connected to the first end face of the existing concrete frame column, which can serve as the direct support point for the new steel beam, transferring the load of the new steel beam to the first anchor. The second anchor plate is fixedly connected to the third end face of the existing concrete frame column, forming a rigid connection through the existing concrete frame column with the first anchor plate via through bolts, thereby balancing the pressure borne by the first anchor plate and restraining the deformation of the existing concrete frame column. The double anchor plates clamp the surface of the existing concrete frame column, avoiding local crushing of the existing concrete frame column caused by single-point stress. Combined with the axial force transmission of the through bolts, the tensile bearing capacity of the joint can be improved. Furthermore, the modular design (anchor plate and steel bar) simplifies the processing and installation process. The through bolts can be prefabricated in the factory, requiring only drilling and fixing on site, without relying on wet concrete work, shortening the construction time and further avoiding the problem of long construction cycles for new beam steel structure joints in existing columns.

[0009] Preferably, the existing concrete frame column has a through hole extending from the first end face to the third end face, the through hole penetrating the existing concrete frame column, the through hole being used to accommodate the through bolt to restrict the position of the first anchor plate and the second anchor plate.

[0010] By adopting the above technical solution, the through hole can ensure the coaxiality of the through bolt and the anchor plate, and reduce the additional bending moment at the node caused by eccentric force; the factory-prefabricated through bolt can be directly inserted into the hole and fixed with the anchor plate by welding or bolting, without the need for temporary formwork or wet concrete work, thus shortening the installation time of a single node.

[0011] Preferably, the second anchor includes a third anchor plate and a fourth anchor plate. The third anchor plate is fixedly connected to the second end face, and the fourth anchor plate is fixedly connected to the fourth end face. Shear reinforcement is provided on both the third and fourth anchor plates, and the shear reinforcement is fixedly connected to the existing concrete frame column.

[0012] By adopting the above technical solution, the third anchor plate and the fourth anchor plate are fixedly connected to the second and fourth end faces of the existing concrete frame column, respectively, which can form a lateral symmetrical constraint, enabling the node to have shear resistance in the horizontal direction and improving the overall structural redundancy; the connection between the shear reinforcement and the column can limit the out-of-plane displacement of the first anchor, transmit the lateral tensile force borne by the anchor plate, and offset the torque generated by the steel beam load.

[0013] Preferably, both the first anchor plate and the second anchor plate are provided with a first through hole for accommodating the through bolt, and both the third anchor plate and the fourth anchor plate are provided with a second through hole for accommodating the shear reinforcement.

[0014] By adopting the above technical solution, the first and second through holes can accommodate the through bolts and shear reinforcement, and position the through bolts and shear reinforcement to ensure their axial position. The first and second through holes facilitate the quick insertion of the through bolts and shear reinforcement by construction personnel, and further avoid the problem of long construction period for new beam steel structure nodes in existing columns.

[0015] Preferably, both the second end face and the fourth end face are provided with receiving holes, which are used to receive the shear reinforcement to limit the position of the third anchor plate and the fourth anchor plate.

[0016] By adopting the above technical solution, the receiving hole can provide an insertion path for the shear reinforcement, ensure the fit between the third and fourth anchor plates and the existing concrete frame column, and form a double-hole positioning with the second through hole to ensure the accurate positioning of the shear reinforcement.

[0017] Preferably, the surface of the existing concrete frame column is chipped to thicken the anchor plate, the outer surface of the existing concrete frame column is provided with interface adhesive, and rebar adhesive is provided in both the through hole and the receiving hole.

[0018] By adopting the above technical solution, surface roughening can create an uneven, rough surface on the existing concrete frame column, thus providing a basis for interface adhesive and mechanical anchoring. The roughened interface forms a rigid connection with the first, second, third, and fourth anchor plates through the interface adhesive, allowing the load to be evenly distributed to the existing concrete frame column through the adhesive layer, avoiding local stress concentration. Injecting anchoring adhesive into the through holes and receiving holes can fill the gap between the reinforcing bars and the hole walls to a certain extent. The chemical bonding force of the adhesive layer anchors the through bolts and anchoring bars to the existing concrete frame column, ensuring the stability of the position of the through bolts and anchoring bars relative to the existing concrete frame column. Furthermore, the interface adhesive and anchoring adhesive typically only require 24 hours to solidify, reducing waiting time and avoiding the problem of long construction cycles for new beam steel structure joints in existing columns.

[0019] Preferably, the newly added steel beam includes a cantilever section steel beam, a connecting plate, and a shear key. The cantilever section steel beam is fixedly connected to the first anchor plate, the connecting plate is fixedly connected to the first anchor plate, the connecting plate is fixedly connected to the cantilever section steel beam, the shear key is fixedly connected to the first anchor plate, and the shear key is fixedly connected to the cantilever section steel beam.

[0020] By adopting the above technical solutions, the cantilever steel beam, as the main load-bearing component of the newly added steel beam, can transfer the load (vertical and horizontal forces) to the first anchor, and then distribute it to the second anchor and the existing concrete frame column through the through bolts, ensuring the load-bearing capacity of the newly added steel beam; the connecting plate can form a transition force transmission area, expand the load transmission area of ​​the cantilever steel beam, and avoid stress concentration that could cause the first anchor plate to crack; the shear key can be connected to the cantilever steel beam to ensure that the cantilever steel beam remains stable under horizontal loads.

[0021] Preferably, two connecting plates are provided, which are disposed on both sides of the cantilever steel beam. The two connecting plates are used to improve the connection strength between the cantilever steel beam and the first anchor plate.

[0022] By adopting the above technical solution, the two connecting plates are respectively attached to both sides of the cantilever steel beam, which transforms the vertical load of the cantilever steel beam into the axial tensile and compressive stress and shear stress of the through bolt, and limits the torque that the cantilever steel beam may generate, so as to prevent the first anchor plate from warping due to eccentric force and ensure the stability of the entire structure under complex loads.

[0023] Secondly, this application provides a construction method for adding new beam steel structure nodes based on existing columns, using the following technical solution: A construction method for adding new beam-steel structure nodes based on existing columns includes the following steps: Pre-treatment of existing concrete frame columns; Set a first anchor and a second anchor, connect the first anchor and the existing concrete frame column, connect the second anchor and the existing concrete frame column, and connect the first anchor and the second anchor. Connect the first anchor and the newly added steel beam.

[0024] By adopting the above technical solution, existing concrete frame columns can complete the addition of new beam steel structure nodes without demolishing the original frame columns. The rigid contact of metal components directly improves the pull-out resistance and shear stiffness of the nodes, thereby compressing the concrete curing period of seven to fourteen days in traditional construction to about twenty-four hours of component installation time, avoiding the problem of long construction period for adding new beam steel structure nodes to existing columns.

[0025] In summary, this application includes at least one of the following beneficial technical effects: 1. The existing reinforced concrete column serves as the core load-bearing structural component, providing a supporting framework for the foundation. Its four end faces provide connection nodes for the first and second anchors. The first anchor penetrates the existing reinforced concrete column, with both ends fixed to the first and third end faces of the column, while simultaneously connecting to the newly added steel beam, bearing and transferring the steel beam load to the existing reinforced concrete column. The second anchor is fixed to the second and fourth end faces of the existing reinforced concrete column and connects to the first anchor, forming a confinement loop that enhances the pull-out and shear resistance of the first anchor. Specifically, the existing reinforced concrete column, the first anchor, and the second anchor form a spatial force-bearing system through a combination of through-anchoring and multi-directional end-face constraints. Without requiring concrete curing strength, the rigid contact of the metal components directly enhances the pull-out resistance and shear stiffness of the joint, thereby compressing the traditional seven- to fourteen-day concrete curing period into approximately twenty-four hours of component installation time. This improves upon the long construction period of adding steel beam joints to existing columns. 2. The first anchor plate is fixedly connected to the first end face of the existing concrete frame column, serving as a direct support point for the new steel beam and transferring the load of the new steel beam to the first anchor. The second anchor plate is fixedly connected to the third end face of the existing concrete frame column, forming a rigid connection through the existing concrete frame column via through bolts. This balances the pressure borne by the first anchor plate and constrains the deformation of the existing concrete frame column. The double anchor plates clamp the surface of the existing concrete frame column, preventing local crushing of the existing concrete frame column caused by single-point stress. Combined with the axial force transmission of the through bolts, the tensile bearing capacity of the joint can be improved. Furthermore, the modular design (anchor plate and reinforcing bar) simplifies the processing and installation process. The through bolts can be prefabricated in the factory, requiring only drilling and fixing on site, eliminating the need for wet concrete work, shortening the construction time, and further avoiding the problem of long construction cycles for new beam steel structure joints in existing columns. 3. Existing concrete frame columns can have new beam-steel structure nodes added without demolishing the original frame columns. Without requiring concrete curing strength, the rigid contact of metal components directly improves the pull-out force and shear stiffness of the nodes, thereby compressing the traditional seven to fourteen-day concrete curing period into approximately twenty-four hours of component installation time. This avoids the problem of long construction cycles for adding beam-steel structure nodes to existing columns. Attached Figure Description

[0026] Figure 1 This is a structural schematic diagram of the newly added beam steel structure node based on the existing column in the embodiments of this application; Figure 2 This is a top view of the newly added beam steel structure node based on the existing column in the embodiments of this application; Figure 3 yes Figure 2 Sectional view of line AA in the middle; Figure 4 This is a schematic diagram of the structure of the first anchor plate in an embodiment of this application; Figure 5 This is a front view of the newly added beam steel structure node based on the existing column in the embodiments of this application; Figure 6 yes Figure 5 A cross-sectional view along the BB line.

[0027] Explanation of reference numerals in the attached drawings: 1. Existing concrete frame column; 11. First end face; 12. Second end face; 13. Third end face; 14. Fourth end face; 2. First anchor; 21. First anchor plate; 22. Second anchor plate; 23. Through bolt; 24. First through hole; 3. Second anchor; 31. Third anchor plate; 32. Fourth anchor plate; 33. Shear reinforcement; 34. Second through hole; 4. Rebar adhesive; 5. Newly added steel beam; 51. Cantilever steel beam; 52. Connecting plate; 53. High-strength bolt; 54. Shear key; 6. Interface adhesive. Detailed Implementation

[0028] The following is in conjunction with the appendix Figures 1-6 This application will be described in further detail.

[0029] This application discloses a method for adding a new beam-steel structure node based on an existing column. (Refer to...) Figure 1 The new steel structure node based on the existing columns includes the existing concrete frame column 1, the first anchor 2, the second anchor 3, and the new steel beam 5.

[0030] like Figure 1 and Figure 2 As shown, the existing concrete frame column 1 is provided with a first end face 11, a second end face 12, a third end face 13 and a fourth end face 14. The first end face 11 and the third end face 13 are arranged opposite each other, and the second end face 12 and the fourth end face 14 are arranged opposite each other. The existing concrete frame column 1 serves as the core load-bearing structural component and can provide a supporting frame for the foundation. The four end faces can provide connection nodes for the first anchor 2 and the second anchor 3.

[0031] In the embodiments of this application, please refer to Figure 2 and Figure 3 The existing concrete frame column 1 has a through hole extending from the first end face 11 to the third end face 13. The through hole penetrates the existing concrete frame column 1 and is used to accommodate the through bolt 23 to limit the position of the first anchor plate 21 and the second anchor plate 22. The through hole allows the first anchor 2 to pass through, thereby ensuring the stability of the position of the first anchor 2, reducing the additional bending moment at the node caused by eccentric force, eliminating the need for temporary formwork or wet concrete work, and shortening the installation time of a single node.

[0032] It should be noted that, please refer to Figure 1 and Figure 4In this embodiment, both the second end face 12 and the fourth end face 14 are provided with receiving holes. These holes are used to accommodate a portion of the second anchor 3, thus limiting the position of the second anchor 3. The surface of the existing concrete frame column 1 is chiseled to remove the anchor plate thickness. Optionally, the surface can also be roughened. An interface adhesive 6 is provided on the outer surface of the existing concrete frame column 1, and rebar adhesive 4 is provided in both the through hole and the receiving hole. The receiving hole provides an insertion path for the second anchor 3, ensuring the fit between the second anchor 3 and the existing concrete frame column 1. Surface roughening creates an uneven, rough surface on the existing concrete frame column 1, providing a basis for the interface adhesive 6 and mechanical anchoring. The interface adhesive 6 can be used to adhere any anchor plate. After roughening... The rough interface forms a rigid connection with the first anchor 2 and the second anchor 3 through the interface adhesive 6, allowing the load to be evenly distributed to the existing concrete frame column 1 through the adhesive layer, avoiding local stress concentration. The injection of anchoring adhesive 4 into the through hole and the receiving hole can fill the gap between the first anchor 2 and the second anchor 3 and the hole wall to a certain extent. The chemical bonding force of the adhesive layer anchors the first anchor 2 and the second anchor 3 to the existing concrete frame column 1, ensuring the stability of the position of the first anchor 2 and the second anchor 3 relative to the existing concrete frame column 1. Furthermore, the interface adhesive 6 and the anchoring adhesive 4 usually only need 24 hours to solidify, reducing the waiting time and avoiding the problem of long construction cycles for new beam steel structure joints in existing columns.

[0033] For example, in this embodiment of the application, the cross-sectional width of the existing concrete frame column 1 is 355mm~365mm, the cross-sectional length of the existing concrete frame column 1 is 455mm~465mm, and the thickness of the chiseled anchor plate is 18mm~22mm at the position corresponding to the first anchor 2 and the second anchor 3.

[0034] like Figure 2 and Figure 3 As shown in the embodiment of this application, the first anchor 2 penetrates the existing concrete frame column 1, and is fixedly connected to the first end face 11 and the third end face 13. The first anchor 2 is also fixedly connected to the newly added steel beam 5 to support the newly added steel beam 5. The first anchor 2 penetrates the existing concrete frame column 1, and its two ends are fixed to the first and third end faces 13 of the column. At the same time, it is connected to the newly added steel beam 5 to bear and transfer the load of the steel beam to the existing concrete frame column 1.

[0035] In this embodiment, the first anchor 2 includes a first anchor plate 21, a second anchor plate 22, and a through bolt 23. The first anchor plate 21 is fixedly connected to the first end face 11 and the newly added steel beam 5. The second anchor plate 22 is fixedly connected to the third end face 13. The through bolt 23 is inserted into the existing concrete frame column 1, and its two ends are fixedly connected to the first anchor plate 21 and the second anchor plate 22, respectively. The first anchor plate 21 is fixedly connected to the first end face 11 of the existing concrete frame column 1, and can serve as a direct support point for the newly added steel beam 5, transferring the load of the newly added steel beam 5 to the first anchor 2. The second anchor plate 22 is fixedly connected to the third end face 13 of the existing concrete frame column 1, and can... The through bolts 23 and the first anchor plate 21 form a rigid connection that penetrates the existing concrete frame column 1, thereby balancing the pressure on the first anchor plate 21 and constraining the deformation of the existing concrete frame column 1. The double anchor plates clamp the surface of the existing concrete frame column 1, avoiding local crushing of the existing concrete frame column 1 caused by single-point stress. Combined with the axial force transmission of the through bolts 23, the tensile bearing capacity of the joint can be improved. Furthermore, the modular design (anchor plate and through bolts 23) simplifies the processing and installation process. The through bolts 23 can be prefabricated in the factory and only need to be drilled and fixed on site. There is no need to rely on wet concrete work, which shortens the construction time and further avoids the problem of long construction cycle of adding new beam steel structure joints to existing columns.

[0036] It should be noted that in this embodiment, the first anchor plate 21 and the second anchor plate 22 are of the same specifications. Both the first anchor plate 21 and the second anchor plate 22 are provided with a first through hole 24. The first through hole 24 is used to accommodate the through bolt 23 and to position the through bolt 23, ensuring the axial position of the through bolt 23. This facilitates the construction personnel to quickly insert the through bolt 23, improves construction efficiency, and further avoids the problem of a long construction period for adding new beam steel structure nodes to existing columns.

[0037] For example, in this embodiment of the application, the first anchor plate 21 and the third anchor plate 31 have the same specifications. Both the first anchor plate 21 and the third anchor plate 31 are metal plates. The length of the first anchor plate 21 is 398mm~402mm, the width of the first anchor plate 21 is 19mm~21mm, the height of the first anchor plate 21 is 798mm~802mm, the diameter of the through bolt 23 is 20mm, and eight first through holes 24 are provided. The eight first through holes 24 are arranged in four rows and two columns on the first anchor plate 21. The center distance between the first through holes 24 in each row and the adjacent first through holes 24 is 160mm, and the center distance between the first through holes 24 in each column and the adjacent first through holes 24 is 200mm.

[0038] like Figure 5 and Figure 6As shown, the second anchor 3 is fixedly connected to the second end face 12 and the fourth end face 14, and is fixedly connected to the first anchor 2. The second anchor 3 is used to improve the pull-out resistance and shear resistance of the first anchor 2.

[0039] In this embodiment, the second anchor 3 includes a third anchor plate 31 and a fourth anchor plate 32. The third anchor plate 31 is fixedly connected to the second end face 12, and the fourth anchor plate 32 is fixedly connected to the fourth end face 14. Shear reinforcement 33 is provided on both the third anchor plate 31 and the fourth anchor plate 32, and the shear reinforcement 33 is fixedly connected to the existing concrete frame column 1. The third anchor plate 31 and the fourth anchor plate 32 are fixedly connected to the second end face 12 and the fourth end face 14 of the existing concrete frame column 1, respectively, which can form a lateral symmetrical constraint, enabling the node to have shear resistance in the horizontal direction and improving the overall structural redundancy. The connection between the shear reinforcement 33 and the column can limit the out-of-plane displacement of the first anchor 2, transmit the lateral tensile force borne by the anchor plate, and offset the torque generated by the steel beam load.

[0040] It should be noted that, in this embodiment of the application, both the third anchor plate 31 and the fourth anchor plate 32 are provided with a second through hole 34, which is used to accommodate the shear reinforcement 33. The second through hole 34 can accommodate the shear reinforcement 33 and limit the shear reinforcement 33, determine the axial position of the shear reinforcement 33, so that construction personnel can easily insert the shear reinforcement 33, and further avoid the problem of long construction period of the new beam steel structure node in the existing column.

[0041] For example, in this embodiment of the application, the second anchor plate 22 and the fourth anchor plate 32 have the same specifications. Both the second anchor plate 22 and the fourth anchor plate 32 are metal plates. The length of the second anchor plate 22 is 458mm~462mm. The width of the first anchor plate 21 is 19mm~21mm. The height of the first anchor plate 21 is 798mm~802mm. The diameter of the shear reinforcement 33 is 20mm. The anchoring depth of the shear reinforcement 33 is 158mm~162mm. Eight second through holes 34 are provided. The eight second through holes 34 are arranged in four rows and two columns on the second anchor plate 22. The center distance between the first through hole 24 in each row and the adjacent first through hole 24 is 160mm. The center distance between the first through hole 24 in each column and the adjacent first through hole 24 is 200mm.

[0042] like Figure 5 and Figure 6As shown in this embodiment, the newly added steel beam 5 includes a cantilever section steel beam 51, a connecting plate 52, and a shear key 54. The cantilever section steel beam 51 is fixedly connected to the first anchor plate 21. The cantilever section steel beam 51 is provided with two through-welding holes. The connecting plate 52 is fixedly connected to the first anchor plate 21 and the cantilever section steel beam 51. The cantilever section steel beam 51, as the main load-bearing component of the newly added steel beam 5, can transfer the load (vertical force and horizontal force) to the first anchor 2, which is then dispersed by the through bolts 23. The second anchor 3 and the existing concrete frame column 1 are connected to ensure the load-bearing capacity of the newly added steel beam 5; the connecting plate 52 can form a transition force transmission area, expand the load transmission area of ​​the cantilever steel beam 51, and avoid stress concentration that could cause the first anchor plate 21 to crack; the shear key 54 is set at the bottom of the cantilever steel beam 51 and is welded to the cantilever steel beam 51 and the first anchor plate 21. Through the connection stiffness and strength with the cantilever steel beam 51 and the first anchor plate 21, the node is ensured to remain stable under horizontal load.

[0043] In this embodiment, two connecting plates 52 are provided, both of which are metal plates. The two connecting plates 52 are located on both sides of the cantilever steel beam 51 and are welded to the first anchor plate 21. The two connecting plates 52 are connected to the cantilever steel beam 51 by high-strength bolts. The two connecting plates 52 are used to improve the connection strength between the cantilever steel beam 51 and the first anchor plate 21. The two connecting plates 52 are respectively attached to both sides of the cantilever steel beam 51, which converts the vertical load of the cantilever steel beam 51 into the axial tensile and compressive stress and shear stress of the through bolts 23, and limits the torque that the cantilever steel beam 51 may generate, so as to prevent the first anchor plate 21 from warping due to eccentric force and ensure the stability of the entire structure under complex loads.

[0044] For example, in the embodiments of this application, the cantilever steel beam 51 includes, but is not limited to, I-beams or H-beams. One end of the cantilever steel beam 51 is welded to the first anchor plate 21, and both connecting plates 52 are welded to the first anchor plate 21. The two connecting plates 52 are respectively disposed on both sides of the web of the cantilever steel beam 51, and the two connecting plates 52 are threadedly connected to the web of the cantilever steel beam 51 by high-strength bolts 53.

[0045] Optionally, in this application, the cantilever steel beam 51 is exemplified by an H-beam: the cantilever steel beam 51 is an HN500×200 steel beam, the high-strength bolts 53 on the connecting plate 52 are set to ten, the length of the connecting plate 52 is 170mm, the width of the connecting plate 52 is 16mm, the height of the connecting plate 52 is 420mm, the ten high-strength bolts 53 are arranged in five rows and two columns on the connecting plate 52, the center distance between each high-strength bolt 53 in each column and the center distance between each high-strength bolt 53 in each row and the center distance between each high-strength bolt 53 and the adjacent high-strength bolt 53 is 80mm.

[0046] Optionally, in this application, the cantilever steel beam 51 is exemplified by an H-beam: the cantilever steel beam 51 is an HN396×199 steel beam, and three high-strength bolts 53 are set on the connecting plate 52. The length of the connecting plate 52 is 60mm, the width of the connecting plate 52 is 12mm, the height of the connecting plate 52 is 170mm, and the three high-strength bolts 53 are arranged in a row on the connecting plate 52. The center distance between each high-strength bolt 53 and the adjacent high-strength bolt 53 is 80mm.

[0047] Specifically, the existing concrete frame column 1, the first anchor 2, and the second anchor 3 form a spatial stress-bearing structural system by adopting a combination of through anchoring and multi-directional end face restraint. Without the need for concrete curing strength, the rigid contact of the metal components directly enhances the pull-out force and shear stiffness of the joint, thereby compressing the traditional seven to fourteen-day concrete curing period into a component installation time of approximately twenty-four hours. This avoids the problem of a long construction period for adding new beam steel structure joints to existing columns.

[0048] For example, a shear key can also be provided at the connection between the first anchor 2 and the cantilever steel beam 51 to enhance the connection stiffness and strength between the first anchor 2 and the cantilever steel beam 51, and ensure that the node remains stable under horizontal load.

[0049] This application also discloses a construction method for adding a new beam-steel structure node based on an existing column. The construction method for adding a new beam-steel structure node based on an existing column includes the following steps: S1, Pre-treatment of existing concrete frame column 1.

[0050] In step S1, the construction workers chisel out a depth of 18mm to 22mm in the area where the existing concrete frame column 1 is connected to the first anchor plate 21, the second anchor plate 22, the third anchor plate 31 and the fourth anchor plate 32 to form a rough surface on the column body. Then, a through hole is opened from the first end face 11 of the existing concrete frame column 1 to the third end face 13, and several receiving holes are opened on the second end face 12 and the fourth end face 14 of the existing concrete frame column 1.

[0051] In this step, the surface of the existing concrete frame column 1 is roughened to form an uneven surface, providing a mechanical anchoring base for the interface adhesive 6 and enhancing the bonding force between the anchor and the column; receiving holes are opened to provide an installation channel for the shear reinforcement 33, ensuring the positioning accuracy of the first anchor plate 21 and the second anchor plate 22 and limiting their displacement.

[0052] S2, set the first anchor 2 and the second anchor 3, connect the first anchor 2 and the existing concrete frame column 1, connect the second anchor 3 and the existing concrete frame column 1, and connect the first anchor 2 and the second anchor 3.

[0053] In step S2, the construction workers open corresponding first through holes 24 and second through holes 34 on the first anchor plate 21, second anchor plate 22, third anchor plate 31, and fourth anchor plate 32. Through bolts 23 are inserted into the first through holes 24 of the first anchor plate 21, and the through bolts 23 and the first anchor plate 21 are welded together to form a "first anchor plate 21 and through bolt 23 assembly". The through bolts 23 are then inserted into the through holes, protruding from the third end face 13. Rebar adhesive 4 is then injected into the through holes to fix the through bolts 23. The construction workers then place shear reinforcement bars 33 into the corresponding second through holes 34 of the second anchor plate 22 or fourth anchor plate 32 and weld them together. After the shear reinforcement 33 and the corresponding second anchor plate 22 or fourth anchor plate 32 are welded, the shear reinforcement 33 is placed into the corresponding receiving hole and the anchoring adhesive 4 is injected into the receiving hole. After the above operations are completed, the first anchor plate 21, the third anchor plate 31 and the fourth anchor plate 32 are welded to the adjacent anchor plates by through-hole plug welding between the anchor plates. The second anchor plate 22 and the part of the through bolt 23 protruding from the third end face 13 are welded, and the second anchor plate 22 is welded to the adjacent anchor plate by through-hole plug welding between the anchor plates. Finally, the interface adhesive 6 is filled between the four anchor plates and the existing concrete frame column 1 to complete the installation of the first anchor 2 and the second anchor 3.

[0054] In this step, the through bolts 23 of the first anchor 2 penetrate the column to form an axial force transmission path; the shear reinforcement 33 of the second anchor 3 provides lateral constraint, improving the shear resistance of the joint; the first anchor plate 21 and the second anchor plate 22 clamp the column surface, and together with the lateral fixation of the third anchor plate 31 and the fourth anchor plate 32, they form a spatial constraint of "penetration and end face", balancing the bending moment and torque generated by the load; welding between anchors and filling with anchoring adhesive 4 ensure rigid contact between the metal component and the concrete column, avoiding stress concentration caused by gaps; the anchor plate-reinforcement assembly only requires drilling, welding, and grouting, eliminating the traditional formwork and rebar tying processes; the interface adhesive 6 and anchoring adhesive 4 solidify in 24 hours, replacing the 7 to 14-day concrete curing period, avoiding the problem of long construction cycles for new beam steel structure joints in existing columns.

[0055] S3 connects the first anchor 2 and the newly added steel beam 5.

[0056] In step S3, the cantilever section steel beam 51 is welded to the first anchor plate 21, and connecting plates 52 are set on both sides of the web of the cantilever section steel beam 51. The connecting plates 52 are welded to the first anchor plate 21, and the two connecting plates 52 are threadedly connected to the web of the cantilever section steel beam 51 by high-strength bolts 53.

[0057] In this step, the vertical force (such as self-weight and external load) and horizontal force borne by the cantilever steel beam 51 are transferred to the first anchor plate 21 through the connecting plate 52, and then distributed to the existing concrete frame column 1 and the second anchor 3 through the through bolts 23; the double connecting plates 52 clamp the web of the cantilever steel beam 51, and the combination of welding (connecting plate 52 and anchor plate) and high-strength bolts (connecting plate 52 and cantilever steel beam 51) improves the shear and tensile strength of the interface; the connecting plate 52 expands the contact area between the cantilever steel beam 51 and the anchor plate, so that the load is evenly distributed and the first anchor plate 21 is prevented from cracking due to excessive local stress.

[0058] Furthermore, in this step, the double connecting plate 52 restricts the lateral displacement and torque of the cantilever steel beam 51, counteracts the eccentric bending moment generated by the steel beam load, ensures the stiffness of the node under complex stress (such as earthquakes and vibrations), reduces the risk of anchor warping, and the high-strength bolt connection facilitates construction adjustment. Moreover, the pre-tightening force of the threaded connection can enhance the interface friction and further improve the overall pull-out resistance. The factory-prefabricated connecting plate 52 and standardized bolt hole positions reduce on-site processing procedures. The combination of welding and bolt connection processes takes into account both connection strength and installation convenience, and shortens the fixing time of the cantilever steel beam 51 after hoisting.

[0059] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A new beam-steel structure node based on existing columns, characterized in that, include: An existing concrete frame column (1) is provided with a first end face (11), a second end face (12), a third end face (13) and a fourth end face (14). The first end face (11) is arranged opposite to the third end face (13), and the second end face (12) is arranged opposite to the fourth end face (14). The first anchor (2) penetrates the existing concrete frame column (1), the first anchor (2) is fixedly connected to the first end face (11) and the third end face (13), and the first anchor (2) is fixedly connected to the newly added steel beam (5) to support the newly added steel beam (5); The second anchor (3) is fixedly connected to the second end face (12) and the fourth end face (14), and is fixedly connected to the first anchor (2). The second anchor (3) is used to improve the pull-out resistance and shear resistance of the first anchor (2).

2. The new beam-steel structure node based on existing columns according to claim 1, characterized in that: The first anchor (2) includes a first anchor plate (21), a second anchor plate (22), and a through bolt (23). The first anchor plate (21) is fixedly connected to the first end face (11) and the newly added steel beam (5). The second anchor plate (22) is fixedly connected to the third end face (13). The through bolt (23) is inserted into the existing concrete frame column (1). The two ends of the through bolt (23) are fixedly connected to the first anchor plate (21) and the second anchor plate (22) respectively.

3. The new beam steel structure node based on existing columns according to claim 2, characterized in that: The existing concrete frame column (1) has a through hole extending from the first end face (11) to the third end face (13). The through hole penetrates the existing concrete frame column (1) and is used to accommodate the through bolt (23) to limit the position of the first anchor plate (21) and the second anchor plate (22).

4. The new beam-steel structure node based on existing columns according to claim 3, characterized in that: The second anchor (3) includes a third anchor plate (31) and a fourth anchor plate (32). The third anchor plate (31) is fixedly connected to the second end face (12), and the fourth anchor plate (32) is fixedly connected to the fourth end face (14). Shear reinforcement (33) is provided on both the third anchor plate (31) and the fourth anchor plate (32). The shear reinforcement (33) is fixedly connected to the existing concrete frame column (1).

5. A new beam-steel structure node based on an existing column as described in claim 4, characterized in that: The first anchor plate (21) and the second anchor plate (22) are each provided with a first through hole (24), which is used to accommodate the through bolt (23). The third anchor plate (31) and the fourth anchor plate (32) are each provided with a second through hole (34), which is used to accommodate the shear reinforcement (33).

6. A new beam-steel structure node based on an existing column according to claim 5, characterized in that: The second end face (12) and the fourth end face (14) are both provided with receiving holes, which are used to receive the shear reinforcement (33) to limit the position of the third anchor plate (31) and the fourth anchor plate (32).

7. A new beam-steel structure node based on an existing column as described in claim 6, characterized in that: The surface of the existing concrete frame column (1) is chiseled to thicken the anchor plate, and the outer surface of the existing concrete frame column (1) is provided with interface adhesive (6). Rebar adhesive (4) is provided in both the through hole and the receiving hole.

8. A new beam-steel structure node based on an existing column as described in claim 2, characterized in that: The newly added steel beam (5) includes a cantilever section steel beam (51), a connecting plate (52), and a shear key (54). The cantilever section steel beam (51) is fixedly connected to the first anchor plate (21), the connecting plate (52) is fixedly connected to the first anchor plate (21), the connecting plate (52) is fixedly connected to the cantilever section steel beam (51), the shear key (54) is fixedly connected to the first anchor plate (21), and the shear key (54) is fixedly connected to the cantilever section steel beam (51).

9. A new beam-steel structure node based on an existing column as described in claim 8, characterized in that: Two connecting plates (52) are provided, and the two connecting plates (52) are provided on both sides of the cantilever steel beam (51). The two connecting plates (52) are used to improve the connection strength between the cantilever steel beam (51) and the first anchor plate (21).

10. A construction method for adding a new beam-steel structure node based on an existing column, using the new beam-steel structure node based on any one of claims 1-9, characterized in that, Includes the following steps: S1, Pre-treatment of existing concrete frame columns (1); S2, set a first anchor (2) and a second anchor (3), connect the first anchor (2) and the existing concrete frame column (1), connect the second anchor (3) and the existing concrete frame column (1), and connect the first anchor (2) and the second anchor (3). S3, connect the first anchor (2) and the newly added steel beam (5).

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