A shear-resistant composite beam joint, composite beam, and retrofit structure for existing buildings

Abstract

The present invention discloses a shear-resistant composite beam joint, a composite beam, and a renovation structure for an existing building, belonging to the technical field of building renovation. It solves the problem in the prior art that in the building renovation method, the shear force transfer between the existing building and the newly added structure needs to be realized. At the same time, it has the advantages of stable connection, high shear bearing capacity, convenient operation, and high construction efficiency. The shear-resistant composite beam joint includes a U-shaped connecting piece, a beam structure anchor bolt, a joint structure anchor bolt, and a through bolt. The second beam is located at the open end of the U-shaped connecting piece, and the first beam is located in the area surrounded by the U-shaped connecting piece and the second beam. The bottom end of the first beam is connected to the bottom end of the U-shaped connecting piece through the joint structure anchor bolt, and the top end of the first beam is connected to the bottom end of the second beam through the beam structure anchor bolt. The through bolt penetrates through the U-shaped connecting piece and the first beam. The shear-resistant composite beam joint, the composite beam, and the renovation structure for the existing building can be used for the reinforcement and renovation of the existing building.

Description

Technical Field

[0001] The present invention belongs to the technical field of building renovation, and particularly relates to a shear-resistant composite beam joint, a composite beam, and a renovation structure of an existing building. Background Art

[0002] In the existing composite beams in the field of building renovation technology, steel bars are wrapped on the surface of the first beam body of the existing building, and then concrete is poured to increase the cross-section of the beam body to form the second beam body.

[0003] The above method has the following problems: On the one hand, in building renovation projects, such as when using the renovation method of adding a steel structure beam, when it is necessary to achieve shear force transfer between the newly added steel structure and the existing concrete, the shear-resistant connection joint style between the newly added steel beam and the existing building concrete beam is not applicable; on the other hand, when manufacturing the composite beam, on-site concrete pouring is required, the operation is complex, and the construction efficiency is low. Summary of the Invention

[0004] In view of the above analysis, the present invention aims to provide a shear-resistant composite beam joint, a composite beam, and a renovation structure of an existing building, which solves the problem of shear force transfer between the existing building and the newly added structure in the existing building renovation method, and has the advantages of stable connection and high shear resistance capacity; at the same time, it solves the problems of complex operation and low construction efficiency of traditional composite beams in the existing technology, and has the advantages of high efficiency, no need for concrete pouring, and dry operation construction method.

[0005] The object of the present invention is mainly achieved through the following technical solutions:

[0006] The present invention provides a shear-resistant composite beam joint for the composite connection of the first beam body and the second beam body in a composite beam. The joint includes a U-shaped connector, a beam structure anchor bolt, a joint structure anchor bolt, and a through bolt. The second beam body is located at the open end of the U-shaped connector, the first beam body is located in the area surrounded by the U-shaped connector and the second beam body, the bottom end of the first beam body is connected to the bottom end of the U-shaped connector through the joint structure anchor bolt, and the top end of the first beam body is connected to the bottom end of the second beam body through the beam structure anchor bolt; the through bolt penetrates through the U-shaped connector and the first beam body.

[0007] Further, the side wall of the U-shaped connector extends to the top end of the second beam body and is equally strong connected (for example, welded) to the top end, bottom end, stiffening rib, and / or side wall of the second beam body.

[0008] Further, the side wall of the U-shaped connector only extends to the bottom end of the second beam body and is equally strong connected (for example, welded) to the bottom end of the second beam body.

[0009] Furthermore, the beam structure anchor bolts are self - drilling mechanical anchor bolts, and / or the joint structure anchor bolts are self - drilling mechanical anchor bolts.

[0010] Furthermore, the shear - resistant composite beam joint includes multiple rows of through - bolts. The multiple rows of through - bolts are divided into single - bolt rows and composite - bolt rows. The number of through - bolts in a single - bolt row is one, and the number of through - bolts in a composite - bolt row is multiple.

[0011] Furthermore, when the number of arranged rows of through - bolts is greater than or equal to 3 and the spacing is not greater than 200 mm.

[0012] Furthermore, the diameter of the through - bolts is greater than or equal to 16 mm.

[0013] Furthermore, the composite - bolt row is close to the top end of the first beam.

[0014] Furthermore, one or two rows close to the top end of the first beam are composite - bolt rows.

[0015] Furthermore, the composite beam joint further includes a pressing plate arranged outside the U - shaped connector and the through - bolts.

[0016] Furthermore, the pressing plate is connected to the first beam through a single - row through - bolt.

[0017] Furthermore, the pressing plate is close to the top end of the first beam and is arranged closely against the lower side of the floor slab associated with the first beam.

[0018] The present invention also provides a composite beam, which can be used for the reinforcement and renovation of existing buildings, and includes a first beam, a second beam, and the above - mentioned shear - resistant composite beam joint. The first beam and the second beam are connected through the joint to achieve shear force transfer.

[0019] Furthermore, the first beam is a concrete beam of an existing building, and the second beam is a steel beam of a newly added steel structure.

[0020] Furthermore, the second beam is an H - shaped steel beam, including a parallel upper flange and a lower flange, and a web connecting the upper flange and the lower flange.

[0021] Furthermore, the above - mentioned second beam further includes stiffening ribs arranged between the upper flange and the lower flange. The upper end of the stiffening rib is connected with the upper flange with equal strength (for example, welded), the lower end of the stiffening rib is connected with the lower flange with equal strength (for example, welded), and the side wall of the stiffening rib is connected with the web with equal strength (for example, welded).

[0022] Furthermore, the side wall of the U - shaped connector extends to the top end of the second beam, and the side wall of the U - shaped connector is respectively connected with the lower flange, the stiffening rib, and the upper flange with equal strength (for example, welded).

[0023] Furthermore, the side wall of the U-shaped connecting piece only extends to the bottom end of the second beam body, and the side wall of the U-shaped connecting piece is only connected with the lower flange with equal strength (for example, welded).

[0024] The present invention also provides a retrofit structure for an existing building, including a steel structure with supports and a support substructure. The steel structure with supports and the concrete structure of the existing building have a floor slab superposition area. The two use the floor slab superposition area to set up superposed beams, forming a floor shear force fully transmitted connection node. The first beam body is a concrete beam of the concrete structure of the existing building, the second beam body is a steel beam of the steel structure with supports, and the support substructure is arranged in the area of the concrete structure of the existing building.

[0025] Furthermore, the superposed beams corresponding to the above floor slab superposition area are arranged in a "well"-shaped two-way plane.

[0026] Compared with the prior art, the present invention can at least achieve one of the following beneficial effects:

[0027] a) The superposed beam node provided by the present invention has two shear connections. Among them, the first beam body and the second beam body are connected by a U-shaped connecting piece, and the first beam body is connected with the U-shaped connecting piece through a through bolt, forming a primary shear connection as the first shear force transmission component group; the first beam body and the second beam body are connected by beam structure anchor bolts, and the first beam body and the U-shaped connecting piece are connected by node structure anchor bolts, forming a secondary shear connection as the second shear force transmission component group. In this way, since the U-shaped connecting piece, the node structure anchor bolt and the through bolt are all rigid parts, the effective transmission of the shear force from the first beam body to the second beam body can be realized;

[0028] b) For the superposed beam node provided by the present invention, the side wall of the U-shaped connecting piece only extends to the bottom end of the second beam body and is connected with the bottom end of the second beam body with equal strength (for example, welded). Since the U-shaped connecting piece does not need to be connected with the upper flange and stiffening ribs of the second beam body, the difficulty of node implementation and the control of the overall civil engineering cost are relatively good. However, when the shear force level borne by the node is relatively high, local warping of the lower flange of the second beam body may occur, resulting in partial degradation of the shear bearing capacity performance of the overall node. Therefore, the superposed beam node style of this embodiment is only applicable to the situation where the shear force value to be transmitted between the existing structure and the new structure is relatively small, and the limited shear bearing capacity of the node can meet the requirements;

[0029] c) The composite beam node provided by the present invention adopts a reinforced double-row through-bolt arrangement near the top of the first beam body to strengthen the effective constraint of the U-shaped connector in the stress concentration area. Since the double-row reinforced bolt constraint measure is adopted for the stress concentration development area of the U-shaped connector, the out-of-plane warping deformation tendency of the U-shaped connector is effectively reduced, and the shear force transfer bearing performance of the node area can be significantly improved. However, the double-row reinforced bolt setting will increase the construction difficulty and civil engineering costs to a certain extent, and will also cause relatively greater structural damage to the existing building concrete structure area. Therefore, the composite beam node style of this embodiment is suitable for situations where the shear force values to be transmitted between the existing structure and the new structure are large, and the existing building concrete structure is in good condition, allowing the setting of reinforced double-row composite bolt rows;

[0030] d) The composite beam node provided by the present invention has a pressure plate arranged on the lower side of the floor slab connected to the first beam body, and is connected to the first beam body by a single row of through bolts, thereby strengthening the effective constraint of the U-shaped connector in the stress concentration area. Since the pressure plate constraint measure is adopted for the stress concentration development area of the U-shaped connector, the out-of-plane warping deformation tendency of the U-shaped connector is effectively reduced, and the shear force transfer bearing performance of the node area can be significantly improved. Therefore, the composite beam node style of this embodiment is suitable for situations where the shear force values to be transferred between the existing structure and the newly added structure are large, and the existing building concrete structure is in poor condition, and it is not suitable to set a reinforced double row of composite bolts;

[0031] e) The integrated reconstruction structure of the existing building provided by the present invention can effectively control the horizontal earthquake action borne by the structural system of the existing building, reduce the implementation scope of the reconstruction and reinforcement measures of the concrete structure of the existing building, reduce the reconstruction and reinforcement engineering volume, and realize the improvement of the economic rationality level of the overall reconstruction and reinforcement engineering, which has important economic significance; it can effectively improve the reconstruction and reinforcement mode of the concrete structure area of the existing building, increase the retention ratio of the historical original appearance of the existing structural area of the existing building as much as possible, effectively ensure the preservation of the original state of the historical style of the existing building, basically realize that the relevant structural beams, columns and other components in the existing concrete structure area can basically meet the bearing capacity and deformation control standards required by the relevant specifications based on the original structural status, eliminate the reconstruction and reinforcement measures of the concrete structure area of the existing building as a whole or in most areas, and realize the purpose of preserving the existing building structure status and the historical style of the existing building to the greatest extent and in the largest scope, that is, realize the reconstruction and reinforcement design purpose of bringing the old with the new and repairing the old as the old; for the existing buildings with certain social, humanistic and historical values, it has important cultural significance.

[0032] Other features and advantages of the present invention will be described in the following description, and part of them will become obvious from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings are only for the purpose of illustrating specific embodiments and are not considered to be a limitation of the present invention. Throughout the drawings, the same reference numerals represent the same components;

[0034] Figure 1 It is a schematic structural diagram of a shear-resistant composite beam joint provided in the first embodiment of the present invention, wherein the side wall of the U-shaped connector extends to the top end of the second beam body;

[0035] Figure 2 It is a side view of a shear-resistant composite beam joint provided in the first embodiment of the present invention, wherein the side wall of the U-shaped connector extends to the top end of the second beam body;

[0036] Figure 3 It is a three-dimensional connection diagram of a shear-resistant composite beam joint provided in the first embodiment of the present invention and the second beam body, wherein the side wall of the U-shaped connector extends to the top end of the second beam body;

[0037] Figure 4 It is a three-dimensional connection diagram of a shear-resistant composite beam joint provided in the first embodiment of the present invention and the first beam body and the second beam body, wherein the side wall of the U-shaped connector extends to the top end of the second beam body; Figure 5 It is a schematic structural diagram of a shear-resistant composite beam joint provided in the first embodiment of the present invention, wherein the side wall of the U-shaped connector extends to the bottom end of the second beam body;

[0038] Figure 6 It is a side view of a shear-resistant composite beam joint provided in the first embodiment of the present invention, wherein the side wall of the U-shaped connector extends to the bottom end of the second beam body;

[0039] Figure 7 It is a three-dimensional connection diagram of a shear-resistant composite beam joint provided in the first embodiment of the present invention and the second beam body, wherein the side wall of the U-shaped connector extends to the bottom end of the second beam body;

[0040] Figure 8 It is a three-dimensional connection diagram of a shear-resistant composite beam joint provided in the first embodiment of the present invention and the first beam body and the second beam body, wherein the side wall of the U-shaped connector extends to the bottom end of the second beam body;

[0041] Figure 9 It is a side view of a shear-resistant composite beam joint provided in the second embodiment of the present invention;

[0042] Figure 10 It is a three-dimensional connection diagram of a shear-resistant composite beam joint provided in the second embodiment of the present invention and the second beam body;

[0043] Figure 11 It is a three-dimensional connection diagram of a shear-resistant composite beam joint provided in the second embodiment of the present invention and the first beam body and the second beam body;

[0044] Figure 12 Schematic diagram of the shear-resistant composite beam joint provided in Embodiment III of the present invention;

[0045] Figure 13 Test diagram of the shear-resistant composite beam joint provided in Embodiment III of the present invention;

[0046] Figure 14 Three-dimensional connection diagram of the shear-resistant composite beam joint provided in Embodiment III of the present invention and the second beam body;

[0047] Figure 15 Three-dimensional connection diagram of the shear-resistant composite beam joint provided in Embodiment III of the present invention and the first beam body and the second beam body;

[0048] Figure 16 Schematic diagram of the deformation of the lower end of the second beam body of the shear-resistant composite beam joint (the side wall of the U-shaped connector extends to the top of the second beam body) provided in Embodiment I of the present invention under the bearing condition;

[0049] Figure 17 Schematic diagram of the deformation of the lower end of the second beam body of the shear-resistant composite beam joint (the side wall of the U-shaped connector extends to the bottom of the second beam body) provided in Embodiment I of the present invention under the bearing condition;

[0050] Figure 18 Schematic diagram of the warping deformation of the side wall of the U-shaped connector in the shear-resistant composite beam joint provided in Embodiment I of the present invention under the bearing condition, wherein the side wall of the U-shaped connector extends to the top of the second beam body;

[0051] Figure 19 Schematic diagram of the warping deformation of the side wall of the U-shaped connector in the shear-resistant composite beam joint provided in Embodiment II of the present invention under the bearing condition;

[0052] Figure 20 Schematic diagram of the warping deformation of the side wall of the U-shaped connector in the shear-resistant composite beam joint provided in Embodiment III of the present invention under the bearing condition;

[0053] Figure 21 Three-dimensional view of the renovation structure of the existing building provided in Embodiment V of the present invention.

[0054] Reference numerals:

[0055] 1 - First beam body; 2 - Second beam body; 21 - Upper flange; 22 - Lower flange; 23 - Web; 24 - Stiffening rib; 3 - U-shaped connector; 4 - Beam structure anchor bolt; 5 - Node structure anchor bolt; 6 - Through bolt; 7 - Pressure plate; 8 - Support sub-structure; 9 - Steel structure with support; 10 - Existing building concrete structure. Detailed implementation manners

[0056] The preferred embodiments of the present invention will be specifically described below in conjunction with the accompanying drawings. The accompanying drawings form a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention.

[0057] Embodiment 1

[0058] This embodiment provides a shear-resistant composite beam joint. Refer to Figures 1 to 8 , which is used for the composite connection of the first beam body 1 and the second beam body 2 in the composite beam. The joint includes a U-shaped connecting piece 3, a beam body structural anchor bolt 4, a joint structural anchor bolt 5, and a through bolt 6. The second beam body 2 is located at the open end of the U-shaped connecting piece 3, and the first beam body 1 is located in the area surrounded by the U-shaped connecting piece 3 and the second beam body 2. The bottom end of the first beam body 1 is connected to the bottom end of the U-shaped connecting piece 3 through the joint structural anchor bolt 5, and the top end of the first beam body 1 is connected to the bottom end of the second beam body 2 through the beam body structural anchor bolt 4; the through bolt 6 penetrates through the U-shaped connecting piece 3 and the first beam body 1.

[0059] Compared with the prior art, the shear-resistant composite beam joint provided in this embodiment has two shear connections. Among them, the first beam body 1 and the second beam body 2 are connected through the U-shaped connecting piece 3, and the first beam body 1 is connected to the U-shaped connecting piece 3 through the through bolt 6, constituting a primary shear connection as the first shear force transmission component group; the first beam body 1 and the second beam body 2 are connected through the beam body structural anchor bolt 4, and the first beam body 1 and the U-shaped connecting piece 3 are connected through the joint structural anchor bolt 5, constituting a secondary shear connection as the second shear force transmission component group. In this way, since the U-shaped connecting piece 3, the joint structural anchor bolt 5, and the through bolt 6 are all rigid members, the complete transmission of the shear force from the first beam body 1 to the second beam body 2 can be realized.

[0060] It should be noted that the extension height of the U-shaped connecting piece 3 can be adopted in the following two ways:

[0061] One way is that the side wall of the U-shaped connecting piece 3 extends to the top end of the second beam body 2 and is connected with the top end, bottom end, and / or side wall of the second beam body 2 with equal strength, that is, fixedly connected (for example, welded). For such a joint, the overall shear force transmission and bearing performance are relatively good, and the construction difficulty and civil engineering cost control are also in a relatively moderate state, which can balance the joint bearing performance, construction difficulty, and civil engineering cost.

[0062] Another way is that the side wall of the U-shaped connecting piece 3 only extends to the bottom end of the second beam body 2 and is connected with the bottom end of the second beam body 2 with equal strength, that is, fixedly connected (for example, welded). In actual applications, it can be selected according to the shear force requirements of the composite beam. For such a joint, the overall construction difficulty and civil engineering cost control are relatively good. However, under the shear force transmission and bearing conditions, local warping may occur at the bottom end of the second beam body 2, resulting in partial degradation of the overall joint shear bearing capacity performance, so it is only applicable to the case where the shear force value to be transmitted is relatively small.

[0063] Regarding the selection of the types of beam structure anchor bolts 4 and node structure anchor bolts 5, illustratively, the beam structure anchor bolts 4 may be self-cutting mechanical anchor bolts, and similarly, the node structure anchor bolts 5 may also be self-cutting mechanical anchor bolts.

[0064] Embodiment 2

[0065] This embodiment provides a shear-resistant composite beam node. Figures 9 to 11 Its structure is basically the same as the structure of the shear-resistant composite beam node provided in the first embodiment, except that the number and arrangement of the through bolts 6 are different.

[0066] Specifically, the shear-resistant composite beam node provided in this embodiment includes multiple rows of through bolts 6, which are divided into single bolt rows and composite bolt rows. The number of through bolts 6 in a single bolt row is one, and the number of through bolts 6 in a composite bolt row is multiple.

[0067] Compared with the prior art, the shear-resistant composite beam node provided in this embodiment has the beneficial effects of the shear-resistant composite beam node provided in the first embodiment, and also has the following beneficial effects:

[0068] By arranging a plurality of through bolts 6 in multiple rows, the connection stability between the U-shaped connector 3 and the first beam body 1 can be effectively increased, thereby increasing the restraining force on the U-shaped connector 3 and the first beam body 1 .

[0069] Compared with the shear-resistant composite beam node provided in the first embodiment, the shear-resistant composite beam node of this embodiment adopts a reinforced double-row arrangement to strengthen the effective constraint of the U-shaped connector 3 in the stress concentration area. Since the double-row reinforced bolt constraint measures are adopted for the stress concentration development area of the U-shaped connector 3, the out-of-plane warping deformation tendency of the U-shaped connector 3 is effectively reduced, and the shear force transmission bearing performance of the node area can be significantly improved. However, the double-row reinforced bolt setting will increase the construction difficulty and civil engineering costs to a certain extent, and will also cause relatively greater structural damage to the existing building concrete structure 10 area. Therefore, the shear-resistant composite beam node style of this embodiment is suitable for situations where the shear force value to be transmitted is large, and the existing building concrete structure 10 is in good condition, allowing the setting of a composite bolt row.

[0070] As for the number of rows of through bolts 6 and the spacing between two adjacent rows of through bolts 6, when the number of rows of through bolts 6 is greater than or equal to 3 and the spacing is not greater than 200 mm, the effective shear bearing capacity can be basically guaranteed.

[0071] Similarly, for the selection of the diameter of the through bolts 6, to ensure the full play of the shear bearing capacity of the composite beam, since the through bolts 6 are subjected to the combined action of tension, bending and shear, through bolts 6 with a diameter greater than or equal to 16 mm can be used, which can basically ensure the bearing capacity.

[0072] To strengthen the binding force of the U-shaped connector 3 in the stress concentration area, the composite bolt row is close to the top of the first beam body 1. Exemplarily, one row or two rows close to the top of the first beam body 1 are composite bolt rows. This is because, in practical applications, the stress concentration area is mainly located at the connection between the first beam body 1 and the second beam body 2. Setting the composite bolt row close to the top of the first beam body 1 can effectively strengthen the binding force on the U-shaped connector 3 and the first beam body 1 in the stress concentration area.

[0073] Embodiment III

[0074] This embodiment provides a shear-resistant composite beam joint. Refer to Figures 12 to 15 , the structure of which is basically the same as that of the shear-resistant composite beam joint provided in Embodiment I or Embodiment II, except that: it further includes a pressing plate 7 arranged in the vertical direction of the U-shaped connector 3, and the pressing plate 7 is connected to the first beam body 1 through the through bolts 6.

[0075] Compared with the prior art, the shear-resistant composite beam joint provided in this embodiment has the following beneficial effects while having the beneficial effects of the shear-resistant composite beam joint provided in Embodiment I:

[0076] Through the setting of the pressing plate 7, the U-shaped connector 3 and the through bolts 6 can be limited, thereby improving the binding force on the U-shaped connector 3 and the first beam body 1.

[0077] Compared with the shear-resistant composite beam joint provided in Embodiment I, the shear-resistant composite beam joint of this embodiment is provided with a pressing plate 7 at the top of the first beam body 1, and is effectively anchored to the concrete beam of the existing building concrete structure 10 through the through bolts 6, strengthening the effective constraint on the U-shaped connector 3 in the stress concentration area. Due to the additional pressing plate 7 constraint measure for the stress concentration development area of the U-shaped connector 3, the out-of-plane warping deformation trend of the U-shaped connector 3 is effectively reduced, and the shear force transfer bearing performance in the joint area can be significantly improved, and the improvement amplitude exceeds that of the shear-resistant composite beam joint provided in Embodiment II.

[0078] This type of node style can significantly improve the shear bearing capacity of the node area. However, adding the pressure plate 7 will increase the construction difficulty and civil engineering cost to a certain extent. However, compared with the shear-type composite beam node of the second embodiment, since the bolt density remains the same as that of the shear-type composite beam node of the first embodiment, it will not cause relatively greater structural damage to the first beam body 1. Therefore, the shear-type composite beam node of this embodiment is applicable to the situation where the shear force value to be transmitted is relatively large, and the existing concrete structure of the existing building is in a poor state and it is not suitable to set a composite bolt row.

[0079] To strengthen the binding force on the U-shaped connector 3 in the stress concentration area, the pressure plate 7 is close to the top of the first beam body 1 and is arranged closely against the lower side of the floor slab connected to the first beam body 1. This is because, in practical applications, the stress concentration area is mainly located at the connection between the first beam body 1 and the second beam body 2. Setting the pressure plate 7 close to the top of the first beam body 1 can effectively strengthen the binding force on the U-shaped connector 3 and the first beam body 1 in the stress concentration area.

[0080] It should be noted that when the first beam body 1 is a concrete beam body of an existing building, the top of the first beam body 1 is usually the floor slab, and the pressure plate 7 cannot be set here. Therefore, the pressure plate 7 can be set at a position close to the top of the first beam body 1 and closely against the lower side of the floor slab.

[0081] Embodiment Four

[0082] This embodiment provides a composite beam, including a first beam body 1, a second beam body 2, and the node provided in the first embodiment, the second embodiment, or the third embodiment. The first beam body 1 and the second beam body 2 are connected by the node to achieve shear force transmission.

[0083] Compared with the prior art, the beneficial effects of the composite beam provided in this embodiment are basically the same as those of the shear-type composite beam node provided in the first embodiment, the second embodiment, or the third embodiment, and will not be elaborated here one by one.

[0084] In practical applications, the above composite beam can be used for the reinforcement and renovation of existing buildings. Specifically, the first beam body 1 is a concrete beam body of an existing building, and the second beam body 2 is a steel beam body of a newly added steel structure.

[0085] Regarding the structure of the second beam body 2, specifically, it is an H-shaped steel beam, including a parallel upper flange 21 and a lower flange 22 and a web 23 connecting the upper flange 21 and the lower flange 22.

[0086] To improve the local stability of the second beam body 2, the second beam body 2 further includes stiffening ribs 24 disposed between the upper flange 21 and the lower flange 22. The upper end of the stiffening rib 24 is connected to the upper flange 21 with equal strength (e.g., welded), the lower end of the stiffening rib 24 is connected to the lower flange 22 with equal strength (e.g., welded), and the side wall of the stiffening rib 24 is connected to the web 23 with equal strength (e.g., welded). In this way, by providing the stiffening ribs 24, the local stability of the second beam body 2 can be greatly improved, and further the mechanical strength of the second beam body 2 can be improved.

[0087] It should be noted that based on the structure of the second beam body 2, for the extension height of the U-shaped connector 3, when the side wall of the U-shaped connector 3 extends to the top of the second beam body 2, the side walls of the U-shaped connector 3 are respectively connected to the lower flange 22, the stiffening rib 24 and the upper flange 21 with equal strength (e.g., welded); when the side wall of the U-shaped connector 3 only extends to the bottom of the second beam body 2, the side wall of the U-shaped connector 3 is only connected to the lower flange 22 with equal strength (e.g., welded).

[0088] Embodiment Five

[0089] This embodiment provides a retrofit structure for an existing building, including a steel structure with braces 9 and a support sub-structure 8. The steel structure with braces 9 has a floor slab superposition area with the existing building concrete structure 10 (e.g., a reinforced concrete frame structure). The two use the floor slab superposition area to set up a composite beam to form a floor shear force fully transmitted connection node. The first beam body 1 is a concrete beam of the existing building concrete structure 10, the second beam body 2 is a steel beam of the steel structure with braces 9, and the support sub-structure 8 is arranged in the area of the existing building concrete structure 10.

[0090] Exemplarily, the steel structure with braces 9 is a concentrically braced steel frame structure, a steel frame structure provided with a load-bearing buckling-restrained brace, or a concentrically braced steel frame structure using concrete-filled steel tubes. The existing building concrete structure 10 is a reinforced concrete frame structure. The existing building concrete structure 10 has 5 floors, the steel structure with braces has 7 floors, and the floor shear force is fully transmitted through the composite beam node style between some of the steel beams of the steel structure with braces 9 and some of the concrete beams of the existing building concrete structure 10.

[0091] Compared with the prior art, the integrated renovation structure of existing buildings provided by the present invention can effectively control the horizontal seismic action borne by the concrete structure 10 of existing buildings, narrow the implementation scope of renovation and reinforcement measures for the concrete structure 10 of existing buildings, reduce the amount of renovation and reinforcement work, and improve the economic rationality level of the overall renovation and reinforcement project; effectively improve the renovation and reinforcement mode of the concrete structure 10 of existing buildings, as much as possible increase the retention ratio of the historical original appearance in the current structure area of existing buildings, effectively ensure the preservation of the original historical features of existing buildings, and basically achieve that the relevant structural beams, columns and other components of the concrete structure 10 of existing buildings can basically meet the bearing capacity and deformation control standards required by relevant codes depending on the original structure status, and overall eliminate or mostly eliminate the renovation and reinforcement measures for the concrete structure 10 of existing buildings, so as to achieve the purpose of preserving the current structure status and historical features of existing buildings to the greatest extent and within the largest scope, that is, to achieve the renovation and reinforcement design purpose of "using the new to bring the old and repairing the old as the old"; for existing buildings with certain social, cultural and historical values, it has important cultural significance.

[0092] Specifically, for the above-mentioned integrated renovation structure of existing buildings, on the one hand, the newly built steel structure with supports 9 has a large lateral stiffness and strong horizontal seismic force resistance ability. The newly built steel structure with supports 9 bears the main horizontal seismic load and the vertical load within the corresponding projected area, and the steel structure with supports 9 and the concrete structure 10 of the existing building form a unified structural unit with collaborative bearing, realizing 100% floor shear transfer; the concrete structure 10 of the existing building mainly bears the vertical load within the corresponding projected area, effectively reducing the proportion of the horizontal seismic load borne.

[0093] On the other hand, by using the measure of adding support sub-structures 8 to the concrete structure 10 of the existing building, the horizontal seismic load of the concrete structure 10 of the existing building is further converged and concentrated. On the basis that the newly built steel structure with supports 9 shares the main horizontal seismic load, for the remaining part of the horizontal seismic load borne by the concrete structure 10 of the existing building, by locally setting support sub-structures 8, the horizontal seismic action is further converged and absorbed and concentrated in the area of the added support sub-structures 8, thereby reducing the horizontal seismic force borne by other areas of the concrete structure of the existing building.

[0094] It should be noted that the above-mentioned "new" represents the newly built steel structure with supports 9 system of the overall structure and the support sub-structures 8 added to the area of the concrete structure 10 of the existing building; the "old" represents the original state structure of the area of the concrete structure 10 of the existing building.

[0095] In addition, it should be noted that for the existing building concrete structure 10, except for the locally added support sub-structure 8, the bearing capacity checks of the lateral force resisting members such as the frame beams and frame columns in other main areas can basically meet the code requirements, and there is no need to adopt additional structural reinforcement design measures, which basically matches the design assumption of only bearing the vertical load within its own range.

[0096] To effectively ensure the effective transfer of the horizontal seismic shear force in all directions, the layout of the composite beams is based on the layout of the concrete beams of the existing building concrete structure 10, and the composite beams corresponding to the above-mentioned floor slab composite areas are arranged in a cross-shaped two-way plane.

[0097] Under the shear bearing condition, a general finite element analysis is carried out on the shear-type composite beam joints provided in the first embodiment, the second embodiment and the third embodiment. See Figures 16 to 20 .

[0098] By comparing Figure 16 and Figure 17 it can be seen that when the side wall of the U-shaped connector 3 extends to the top of the second beam body 2, the local warping at the bottom of the second beam body 2 is not obvious, while when the side wall of the U-shaped connector 3 extends to the bottom of the second beam body 2, the local warping at the bottom of the second beam body 2 is more obvious.

[0099] By comparing Figure 18 and Figure 19 it can be seen that compared with the shear-type composite beam joint of the first embodiment without the composite bolt group, the shear-type composite beam joint of the second embodiment can effectively reduce the out-of-plane warping deformation trend of the U-shaped connector 3 by setting the composite bolt group.

[0100] By comparing Figure 18 and Figure 20 it can be seen that compared with the shear-type composite beam joint of the first embodiment without the pressing plate 7, the shear-type composite beam joint of the third embodiment can effectively reduce the out-of-plane warping deformation trend of the U-shaped connector 3 by setting the pressing plate 7.

[0101] It should be noted that for the shear-type composite beam joint, it can be selected according to the shear bearing capacity of a single-section joint area, and the shear bearing capacity of a single-section joint area can be determined in the following three ways:

[0102] Simplified method: Without considering the contribution of the beam structure bolts 4 and the joint structure bolts 5 between the second beam body 2 and the first beam body 1, the shear bearing capacity of the single-section joint area is completely determined according to the shear bearing capacity of the cross-section of the U-shaped connector 3 and considering a safety factor of not less than 1.5.

[0103] Finite element method: Use general finite element software to carry out calculation and modeling of single-section or multi-section joint areas, and determine the shear bearing capacity of the single-section joint area according to the finite element calculation and analysis results.

[0104] Analysis method: According to the mechanical bearing characteristics of the node area, a series of processes including variable setting, establishment and solution of mechanical equilibrium equations, and parameter identification in finite element analysis (note: or experimental method) are carried out to establish the formula for the analytical method of calculating the bearing capacity of a single-section node area, which is used to determine the shear bearing capacity of a single-section node area.

[0105] As mentioned above, it is only the preferred specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention.

Claims

1. A shear-resistant composite beam joint, characterized in that, Shear-resistant composite connection for the first beam body and the second beam body in a composite beam. The joint includes a U-shaped connector, beam structure anchor bolts, joint structure anchor bolts, and through bolts. The second beam body is located at the open end of the U-shaped connector, and the first beam body is located within the area enclosed by the U-shaped connector and the second beam body. The bottom end of the first beam body is connected to the bottom end of the U-shaped connector through joint structure anchor bolts, and the top end of the first beam body is connected to the bottom end of the second beam body through beam structure anchor bolts. The through bolts penetrate through the U-shaped connector and the first beam body. The first beam body and the second beam body are connected through the U-shaped connector, and the first beam body is connected to the U-shaped connector through through bolts, forming a primary shear connection as the first set of shear force transmission components; the first beam body and the second beam body are connected through beam structure anchor bolts, and the first beam body and the U-shaped connector are connected through joint structure anchor bolts, forming a secondary shear connection as the second set of shear force transmission components. The U-shaped connector, joint structure anchor bolts, and through bolts are all rigid components. The side wall of the U-shaped connector extends to the top end of the second beam body and is fixedly connected to the top end, bottom end, and / or side wall of the second beam body.

2. The composite beam joint according to claim 1, wherein The beam structure anchor bolts are self-drilling and tapping mechanical anchor bolts, and / or the joint structure anchor bolts are self-drilling and tapping mechanical anchor bolts.

3. The composite beam joint according to claim 1 or 2, characterized in that, The composite beam joint includes multiple rows of through bolts, which are divided into single bolt rows and composite bolt rows. The number of through bolts in the single bolt row is one, and the number of through bolts in the composite bolt row is multiple.

4. The composite beam joint according to claim 3, characterized in that, The composite bolt row is close to the top end of the first beam body.

5. The composite beam joint according to claim 1 or 2, characterized in that, The composite beam joint further includes a pressing plate arranged in the vertical direction of the U-shaped connector. The pressing plate is connected to the first beam body through a single row of through bolts.

6. The composite beam joint according to claim 5, characterized in that, The pressing plate is close to the top end of the first beam body and is arranged closely against the lower side of the floor slab associated with the first beam body.

7. A composite beam, characterized in that, It includes a first beam body, a second beam body, and the composite beam joint according to any one of claims 1 to 6. The first beam body and the second beam body achieve shear force transmission connection through the joint.

8. A retrofit structure for an existing building, characterized in that, It includes a steel structure with supports. There is a floor slab composite area between the steel structure with supports and the existing building concrete structure. The composite beam is set in the floor slab composite area, forming a floor shear force fully transmitted connection joint. The composite beam is the composite beam according to claim 7. The first beam body is a concrete beam of the existing building concrete structure, and the second beam body is a steel beam of the steel structure with supports.

Images