Later cantilever structure

Abstract

The present invention provides a post-added cantilever structure, including a floor slab, a side beam and a cantilever beam, wherein the side beam is located at the edge of the floor slab, the cantilever beam is perpendicular to the side beam, a cast-in-place trough is provided on the floor slab, and the cantilever beam includes a mounting section, a connecting section and a cantilever section connected in sequence, at least part of the mounting section is fixed in the cast-in-place trough, the bottom of the connecting section has a groove, the connecting section is clamped to the top of the side beam through the groove, and the cantilever section cantilevers outward in a direction away from the floor slab. By fixing at least part of the mounting section in the cast-in-place trough of the floor slab and providing a groove so that the connecting section is clamped to the top of the side beam, the tension of the cantilever section can be directly transmitted to the original main structure, thereby avoiding the reliability problem of relying on post-placed anchor bolts to transmit tension in the traditional method, and the forces of the mounting section and the cantilever section of the cantilever beam reach a balanced state through the pressure of the side beam.

Description

Technical Field

[0001] The invention relates to the technical field of building structures, in particular to a rear-added cantilever structure. Background Art

[0002] In the process of reinforcement and reconstruction, in order to enrich the effect of the facade or indoor atrium, architects often require the addition of cantilevered building space, such as adding a staircase in the atrium and an outdoor terrace on the facade. These are all cases of adding cantilevered structures after passing through the original main structure. Since the cantilevered structure is a force-bearing form with one end constrained and the other end free, this special force transmission method makes how to reliably connect with the original main structure a key point in structural design.

[0003] There are currently two common connection methods, one is to add reinforced concrete beams later, and the other is to add steel beams later to transmit tensile force through chemical anchors.

[0004] Among them, the method of adding reinforced concrete beams later is to implant the main reinforcement of the cantilever beam into the original main structure or to chisel out the concrete of the original main structure beam, and to achieve cantilevering through the tensile strength of the upper row of steel bars and the compression of the lower concrete. Both implanting reinforcement and chiseling out concrete will cause great damage to the original main structure, and temporary support needs to be set up during the construction phase, which can only be removed after the new cantilever beam is cast. This method has low redundancy of a single support point, causes great damage to the original main structure, and requires many construction measures and a long period of time.

[0005] The method of adding steel beams later is to weld anchor plates at the ends of the steel beams, anchor the anchor plates to the original main structure through chemical anchor bolts, and use the tensile strength of chemical anchor bolts to achieve cantilevering. Due to the margin and spacing requirements of chemical anchor bolts, if the cantilever is greater than 2.5m, the size of the embedded parts is large and the anchor bolts cannot meet the force requirements.

[0006] The common feature of the above two connection methods is that they both achieve cantilevering through the tensile strength of post-planted steel bars or chemical anchors. However, both connection methods have the following defects:

[0007] 1) The cantilever structure is subjected to force at a single support point, and has low redundancy;

[0008] 2) A large number of implanted steel bars and chemical anchors cause great damage to the original main structure;

[0009] 3) Due to the limitations of the margins and spacing of embedded reinforcement and chemical anchors, the achievable cantilever distance is relatively short. Summary of the invention

[0010] The purpose of the present invention is to provide a rear-added cantilever structure which can meet the requirements of various sewing processes, is convenient for workers to operate, and can reduce the danger of operation.

[0011] In order to achieve the above-mentioned purpose, the present invention provides a post-added cantilever structure, including a floor slab, a side beam and a cantilever beam, the side beam is located at the edge of the floor slab, the cantilever beam and the side beam are perpendicular to each other, a cast-in-place trough is provided on the floor slab, the cantilever beam includes an installation section, a connecting section and a cantilever section connected in sequence, at least part of the installation section is fixed in the cast-in-place trough, the bottom of the connecting section has a groove, the connecting section is clamped to the top of the side beam through the groove, and the cantilever section cantilevers outward in the direction away from the floor slab.

[0012] Optionally, the cantilever beam includes an upper flange plate, a lower flange plate and a plurality of web plates, the upper flange plate and the lower flange plate are arranged parallel to the floor slab, the web plate is vertically connected between the upper flange plate and the lower flange plate, the upper flange plate is an integral whole, and the lower flange plate and the web plate are disconnected at the edge beam.

[0013] Optionally, the width of the upper flange plate located at the connecting section is greater than the width of the upper flange plates located at the mounting section and the cantilever section.

[0014] Optionally, the cantilever beam is a box steel beam, an I-beam or an H-beam.

[0015] Optionally, the floor slab is a reinforced concrete structure, and the cast-in-place trough is filled with concrete to fix at least a portion of the installation section in the cast-in-place trough.

[0016] Optionally, part of the installation section is fixed in the cast-in-place trough, and the lower bottom surface of the installation section is lower than the lower bottom surface of the floor slab, and the side surface of the installation section is perpendicular to the lower bottom surface of the floor slab and is connected by a plurality of angle steels.

[0017] Optionally, end plates are fixed on opposite sides of the groove, the area of ​​the end plates is larger than the area of ​​the cross section of the cantilever beam, and the end plates are attached to and connected to the outer wall of the side beam.

[0018] Optionally, the end plate is connected to the outer wall of the side beam via a plurality of anchor bolts, and the plurality of anchor bolts are evenly distributed along the edge of the end plate.

[0019] Optionally, the rear-added cantilever structure further includes a structural beam, wherein the structural beam is located on a side of the floor slab away from the side beam, and the installation section extends to the structural beam and is connected to the structural beam.

[0020] Optionally, the axial length of the mounting section is greater than or equal to the axial length of the cantilever section.

[0021] In a post-added cantilever structure provided by the present invention, by dividing the cantilever beam into an installation section, a connection section and a cantilever section, at least part of the installation section is fixed in the cast-in-place groove of the floor slab, and by setting a groove, the connection section is clamped on the top of the side beam, so that the tension of the cantilever section can be directly transmitted to the original main structure, avoiding the reliability problem of relying on post-installed anchor bolts to transmit tension in the traditional method, and the force of the installation section and the cantilever section of the cantilever beam reaches a balanced state through the compression of the side beam. The post-added cantilever structure provided by the present invention not only has clear force transmission, but also improves the original single support and low redundancy node form, improves the redundancy of the cantilever beam, can achieve a larger distance of cantilever, and provides architects with more possibilities in the renovation of existing buildings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Those skilled in the art will appreciate that the accompanying drawings are provided for a better understanding of the present invention and do not constitute any limitation on the scope of the present invention.

[0023] Figure 1 A three-dimensional diagram of a rear cantilever structure provided in an embodiment of the present invention;

[0024] Figure 2 A plan view of a rear-added cantilever structure provided in an embodiment of the present invention;

[0025] Figure 3 An elevation view of a rear-added cantilever structure provided in an embodiment of the present invention;

[0026] Figure 4 A cross-sectional view of the inner side of a connecting section provided by an embodiment of the present invention;

[0027] Figure 5 A cross-sectional view of the outer side of the connecting section provided by an embodiment of the present invention;

[0028] In the attached figure:

[0029] 10-floor slab; 20-side beam; 31-installation section; 32-connection section; 33-cantilever section; 40-angle steel; 50-end plate; 60-structural beam. DETAILED DESCRIPTION

[0030] As described in the background technology, the common feature of the two methods of post-adding reinforced concrete beams and post-adding steel beams through the tensile force transmission of chemical anchors is that cantilevering is achieved through the tensile force of post-embedded steel bars or chemical anchors, and the reliability of tensile anchoring is closely related to the construction process, anchoring length and the quality of the rebar embedding glue, and each link will affect the safety of the cantilever structure.

[0031] The post-connection methods in reinforcement and reconstruction can be divided into compression, tension and shear according to the force form. Among these three types of connections (excluding the influence of anchor bolt margins and spacing), compression and shear mainly depend on the material strength of the structure, while tension mainly depends on the connection process and the material of the connection. The force transmission of shear anchoring mainly depends on the materials of the original components and connecting anchors, and the requirements for anchoring length are relatively low; while the theoretical value of tension anchoring mainly depends on the anchoring length and the quality of the anchoring glue, but in post-reinforcement, the anchoring length is often limited by the size of the original structure, so relatively speaking, the reliability of shear anchoring is higher.

[0032] Considering that shear anchoring is more reliable than tension anchoring, the present invention divides the cantilever beam into an installation section, a connection section and a cantilever section, so that at least part of the installation section is fixed in the cast-in-place groove of the floor slab, and the connection section is clamped on the top of the side beam by setting a groove, so that the tension of the cantilever section can be directly transmitted to the original main structure, avoiding the reliability problem of relying on post-anchor bolts to transmit tension in the traditional method, and the force of the installation section and the cantilever section of the cantilever beam reaches a balanced state through the compression of the side beam. This connection structure not only transmits force clearly, but also improves the original single-support, low-redundancy node form, improves the redundancy of the cantilever beam, and can achieve a larger distance of cantilever, providing architects with more possibilities in the renovation of existing buildings.

[0033] In order to make the purpose, advantages and features of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In addition, the structure shown in the drawings is often a part of the actual structure. In particular, the emphasis of each drawing is different, and sometimes different scales are used.

[0034] As used in the present invention, the singular forms "one", "an", and "the" include plural objects, unless the content clearly indicates otherwise. As used in the present invention, the term "or" is generally used in a sense that includes "and / or", unless the content clearly indicates otherwise. As used in the present invention, the term "several" is generally used in a sense that includes "at least one", unless the content clearly indicates otherwise. As used in the present invention, the term "at least two" is generally used in a sense that includes "two or more", unless the content clearly indicates otherwise. In addition, the terms "first", "second", and "third" are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first", "second", and "third" may explicitly or implicitly include one or at least two of the features.

[0035] like Figure 1-Figure 3 As shown, Figure 1 A three-dimensional diagram of a rear cantilever structure provided by an embodiment of the present invention, Figure 2 A plan view of a rear cantilever structure provided in an embodiment of the present invention, Figure 3 An elevation view of a post-added cantilever structure provided in an embodiment of the present invention. This embodiment provides a post-added cantilever structure, comprising a floor slab 10, a side beam 20 and a cantilever beam, wherein the side beam 20 is located at the edge of the floor slab 10, the cantilever beam and the side beam 20 are perpendicular to each other, a cast-in-place trough is provided on the floor slab 10, the cantilever beam comprises a mounting section 31, a connecting section 32 and a cantilever section 33 connected in sequence, at least part of the mounting section 31 is fixed in the cast-in-place trough, the bottom of the connecting section 32 has a groove, the connecting section 32 is clamped to the top of the side beam 20 through the groove, and the cantilever section 33 cantilevers outward in a direction away from the floor slab 10.

[0036] Specifically, in this embodiment, the cantilever beam includes an upper flange plate, a lower flange plate and a plurality of web plates. The upper flange plate and the lower flange plate are arranged parallel to the floor slab 10, and the web plate is vertically connected between the upper flange plate and the lower flange plate. The upper flange plate is an integral body, and the lower flange plate and the web plate are disconnected at the edge beam 20. Since shear anchoring is more reliable than tension anchoring, the upper flange plate on the inner side (i.e., the installation section 31) of the cantilever beam and the upper flange plate on the outer side (i.e., the cantilever section 33) are connected (i.e., a full-length integral structure), and the web plate and the lower flange plate are disconnected at the original edge beam 20 (i.e., the connecting section 32). After the upper flange plate is connected, the tension can be directly transmitted to the inner side of the original main structure, avoiding the transmission of tension by post-installed anchor bolts, and the web shear force and the pressure of the lower flange are directly transmitted to the edge beam 20 of the original structure, so that the forces on the outer and inner sides of the cantilever reach a self-balanced state through the pressure of the edge beam 20. This method not only transmits force clearly, but also increases the connection points between the added cantilever and the original main structure, improving the redundancy of the cantilever structure.

[0037] It should be noted that the “inside” and “inner side” mentioned in this application refer to the direction relative to the original structural body, and the “outside” and “outer side” refer to the direction in which the cantilever beam is cantilevered.

[0038] For further information, please refer to Figure 2, the width of the upper flange plate located at the connecting section 32 is greater than the width of the upper flange plate located at the mounting section 31 and the cantilever section 33. Since the lower flange plate and the web plate at the connecting section 32 are disconnected, the strength of the connecting section 32 can be increased by increasing the width of the upper flange plate at the connecting section 32, thereby ensuring the force stability of the added cantilever structure. In this embodiment, the widths of the upper flange plates located at the mounting section 31 and the cantilever section 33 are the same, and the width of the upper flange plate located at the connecting section 32 can be transitioned to the mounting section 31 and the cantilever section 33 through a bevel. It should be understood that the width mentioned in this embodiment refers to the width along a direction perpendicular to the axial direction of the cantilever beam.

[0039] The cantilever beam can be a box-shaped steel beam, an I-shaped steel beam or an H-shaped steel beam. In this embodiment, the cantilever beam is a box-shaped steel beam. Of course, the cantilever beam can also be a steel beam of other shapes, and this application does not impose any restrictions on this.

[0040] Please continue to refer to Figure 4 , Figure 4 A cross-sectional view of the inner side of the connection section provided in an embodiment of the present invention. The floor 10 is a reinforced concrete structure, and the cast-in-place trough is filled with concrete to fix at least part of the installation section 31 in the cast-in-place trough. By opening a cast-in-place trough on the floor 10, so as to fix the installation section of the cantilever beam, the force of the cantilever beam can be directly transmitted to the floor 10, and the force form is closer to the new structure, and a larger cantilever distance can be achieved, providing more possibilities for architects in the renovation of existing buildings. In this embodiment, since the floor 10 is a completed reinforced concrete structure, it is necessary to first excavate a cast-in-place trough during the specific construction, and then cut off the steel bars in the cast-in-place trough. The size of the cast-in-place trough should be larger than the size of the cantilever beam. After the cantilever beam is placed, it is also necessary to reconnect the steel bars around the cut cantilever beam, and then recast concrete to fix at least part of the installation section 31 in the cast-in-place trough.

[0041] Furthermore, the cantilever beam can be completely or partially fixed in the cast-in-place trough according to the size of the cantilever beam.

[0042] In this embodiment, please continue to refer to Figure 4 , part of the installation section 31 is fixed in the cast-in-place trough, and the lower bottom surface of the installation section 31 is lower than the lower bottom surface of the floor 10, and the side surface of the installation section 31 is perpendicular to the lower bottom surface of the floor 10 and connected through a plurality of angle steels 40. In other words, the height of the installation section 31 is greater than the thickness of the floor 10, and the bottom of the installation section 31 is to extend out of the floor 10. By arranging the angle steel 40 between the side surface (i.e., the web) of the installation section 31 and the lower bottom surface of the floor 10, the cantilever beam can be further reinforced to improve the reliability of force.

[0043] In this embodiment, one end of the angle steel 40 is affixed and connected to the side of the installation section 31, and the other end is affixed and connected to the lower bottom surface of the floor slab 10. The connection method is, for example, welding, and threaded connection can also be used. This application does not impose any restrictions on this.

[0044] Preferably, there are multiple angle steels 40, and the multiple angle steels 40 are evenly distributed along the axial direction of the cantilever beam. Of course, the present application does not impose any restrictions on the number and distribution of the angle steels 40.

[0045] Please continue to refer to Figure 4 and Figure 5 The groove is provided with end plates 50 on opposite sides thereof, the area of ​​the end plates 50 being larger than the cross-sectional area of ​​the cantilever beam, and the end plates 50 are attached to and connected with the outer wall of the side beam 20. In other words, the connecting section 32 is connected with the side beam 20 through the end plates 50.

[0046] Furthermore, the end plate 50 is connected to the outer wall of the side beam 20 by a plurality of anchor bolts, and the plurality of anchor bolts are evenly distributed along the edge of the end plate 50. The cantilever beam and the side beam 20 are connected by anchoring, which improves the traditional single support and low redundancy connection node form, and since the cantilever beam is grooved, the side beam 20 will not be damaged. It should be understood that the present application also does not impose any restrictions on the number and distribution of the anchor bolts, which can be selected according to needs.

[0047] In this embodiment, the anchor bolt is a chemical anchor bolt, which has strong anchoring force, high force transmission performance and quick installation.

[0048] In this embodiment, the side beam is a reinforced concrete structure.

[0049] During the specific construction, the end plate 50 can be pre-welded on both sides of the groove, and then the entire cantilever beam can be directly hoisted into place. Finally, it is only necessary to connect the cantilever beam with the side beam 20 through anchor bolts, and then cast concrete in the cast-in-place trough. The whole construction process is simple and fast.

[0050] Please continue to refer to Figure 1-Figure 3 The later added cantilever structure further includes a structural beam 60, which is located on the side of the floor 10 away from the edge beam 20, and the installation section 31 extends to the structural beam 60 and is connected to the structural beam 60. By extending one end of the cantilever beam to the structural beam 60 and connecting to the structural beam 60, the connection points between the cantilever beam and the original main structure can be increased, thereby improving the redundancy of the cantilever structure.

[0051] In this embodiment, an end plate 50 may be welded to the end of the installation section 31 and then connected to the structural beam 60 via anchor bolts.

[0052] In this embodiment, the axial length of the mounting section 31 is greater than or equal to the axial length of the cantilever section 33 to prevent the cantilever section 33 from turning up, thereby ensuring the stability of the cantilever beam.

[0053] Based on this, combined Figure 1-Figure 3 The present application also provides a method for installing a cantilever beam, comprising the following steps:

[0054] S1. Make a cantilever beam, the cantilever beam comprising a mounting section 31, a connecting section 32 and a cantilever section 33 connected in sequence, the bottom of the connecting section 32 has a groove, end plates 50 are welded on opposite sides of the groove, and the end plates 50 are also welded on the ends of the mounting section 31;

[0055] S2, opening a cast-in-place trough on the floor slab 10 of the original main structure;

[0056] S3, hoisting the prepared cantilever beam onto the original main structure, and making part of the installation section 31 located in the cast-in-place trough, and the connecting section 32 being clamped to the top of the side beam 20 through the groove;

[0057] S4, installing chemical anchor bolts on the end plate 50 to connect the connecting section and the side beam 20 and the installing section 31 and the structural beam 60;

[0058] S5. Casting concrete in the cast-in-place trough.

[0059] The entire installation method has simple steps and is easy to install. It only requires grooving on the floor 10, and no damage will be caused to the structural beam 60 and the side beam 20 of the original main structure. The connection method is connected by chemical anchor bolts and cast-in-place concrete, which increases the support points of the cantilever beam and improves the original single support and low-redundancy connection node form. The force form of the cantilever beam is closer to the new structure, and a larger cantilever distance can be achieved, providing architects with more possibilities in the renovation of existing buildings.

[0060] In summary, the embodiments of the present invention provide a post-added cantilever structure, which divides the cantilever beam into an installation section, a connection section and a cantilever section, so that at least part of the installation section is fixed in the cast-in-place groove of the floor slab, and the connection section is clamped on the top of the side beam by setting a groove, so that the tension of the cantilever section can be directly transmitted to the original main structure, avoiding the reliability problem of relying on post-installed anchor bolts to transmit tension in the traditional method, and the force of the installation section and the cantilever section of the cantilever beam reaches a balanced state through the compression of the side beam. The post-added cantilever structure provided by the present invention not only has clear force transmission, but also improves the original single support and low redundancy node form, improves the redundancy of the cantilever beam, can achieve a larger distance of cantilever, and provides more possibilities for architects in the renovation of existing buildings.

[0061] The above is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any technician in the relevant technical field, without departing from the scope of the technical solution of the present invention, makes any form of equivalent replacement or modification to the technical solution and technical content disclosed in the present invention, which does not depart from the content of the technical solution of the present invention and still falls within the protection scope of the present invention.

Claims

1. A rear-added cantilever structure, It is characterized in that The invention comprises a floor slab, a side beam and a cantilever beam, wherein the side beam is located at the edge of the floor slab, the cantilever beam is perpendicular to the side beam, a cast-in-place groove is provided on the floor slab, the cantilever beam comprises a mounting section, a connecting section and a cantilever section connected in sequence, at least part of the mounting section is fixed in the cast-in-place groove, the bottom of the connecting section has a groove, the connecting section is clamped to the top of the side beam through the groove, and the cantilever section cantilevers outwardly in a direction away from the floor slab; the cantilever beam comprises an upper flange plate, a lower flange plate and a plurality of web plates, the upper flange plate and the lower flange plate are arranged parallel to the floor slab, the web plate is vertically connected between the upper flange plate and the lower flange plate, the upper flange plate is a whole, and the lower flange plate and the web plate are disconnected at the side beam; The floor slab is a reinforced concrete structure, and the cast-in-place trough is filled with concrete to fix at least a portion of the installation section in the cast-in-place trough.

2. The rear-added cantilever structure as claimed in claim 1, It is characterized in that The width of the upper flange plate located at the connecting section is greater than the width of the upper flange plates located at the mounting section and the cantilever section.

3. The rear-added cantilever structure as claimed in claim 1, It is characterized in that The cantilever beam is a box-shaped steel beam, an I-shaped steel beam or an H-shaped steel beam.

4. The rear-added cantilever structure as claimed in claim 1, It is characterized in that Part of the installation section is fixed in the cast-in-place trough, and the lower bottom surface of the installation section is lower than the lower bottom surface of the floor slab. The side surface of the installation section is perpendicular to the lower bottom surface of the floor slab and is connected by a plurality of angle steels.

5. The rear-added cantilever structure as claimed in claim 1, It is characterized in that End plates are fixed on opposite sides of the groove, the area of ​​the end plates is larger than the area of ​​the cross section of the cantilever beam, and the end plates are attached to and connected to the outer wall of the side beam.

6. The rear-added cantilever structure as claimed in claim 5, It is characterized in that The end plate is connected to the outer wall of the side beam via a plurality of anchor bolts, and the plurality of anchor bolts are evenly distributed along the edge of the end plate.

7. The rear-added cantilever structure according to claim 1, It is characterized in that The post-added cantilever structure further includes a structural beam, which is located on a side of the floor slab away from the edge beam, and the installation section extends to the structural beam and is connected to the structural beam.

8. The rear-added cantilever structure as claimed in claim 1, It is characterized in that The axial length of the mounting section is greater than or equal to the axial length of the cantilever section.

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