Variable cross-section prestressed concrete beam and beam-column connection node structure

Abstract

The invention provides a variable cross-section prestressed concrete beam and a beam-column connection joint structure, and relates to the technical field of fabricated frame structures. The prestressed concrete beam comprises a precast beam body, beam end connecting pieces are embedded in the two beam ends in the extending direction of the precast beam body respectively and used for being fixedly connected with column side connecting pieces in a node area of a precast column body in a screwed mode. The lower part of the precast beam body is provided with prestress applying areas which are symmetrically arranged relative to the midpoint of the precast beam body in the first direction, and a plurality of prestressed tendons which are distributed at intervals in the second direction are arranged in the prestress applying areas; the arrangement range of the prestress applying area in the first direction is located between two inflection points of the precast beam body; wherein the first direction is the extension direction of the precast beam body, and the second direction is the width direction of the precast beam body.

Description

Technical Field

[0001] The present application relates to the technical field of assembled frame structures, and in particular to a variable-section prestressed concrete beam and a beam-column connection node structure. Background Art

[0002] The prefabricated concrete frame structure adopts the form of prefabricated frame columns and composite beams, and realizes rigid connection through post-cast nodes. However, this connection method has problems such as reinforcement of prefabricated components, dense steel bars in the node area, many wet concrete operations on site, and the need for temporary support and formwork. Although the overall construction cost is low, the on-site workload is large and the construction period is long.

[0003] Prestressed concrete structures are prestressed before external loads are applied, thereby offsetting the tensile stress caused by external loads and slowing down the cracking caused by insufficient tensile stiffness of concrete. Especially in large-span structures, prestressed concrete can reduce the cross-sectional area of ​​beams, and has good economy, aesthetics and space utilization.

[0004] However, currently prefabricated prestressed concrete structures mainly use groove connections, which have problems such as reinforcement of prefabricated components, dense steel bars in node areas, and frequent wet concrete operations on site. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide a variable-section prestressed concrete beam and beam-column connection node structure to solve the problems of the current prefabricated prestressed concrete structure mainly using groove connections, with the problems of prefabricated component reinforcement, dense steel bars in the node area, and frequent on-site concrete wet operations.

[0006] In order to solve the above technical problems, the embodiments of the present application provide the following technical solutions:

[0007] A first aspect of the present application provides a prestressed concrete beam, the prestressed concrete beam comprising: a precast beam body, two beam ends in the extension direction of which are respectively pre-buried with beam end connectors for being screwed and fixed to column side connectors in the node area of ​​a precast column body, a prestressing area symmetrically arranged about the midpoint of the precast beam body in the first direction is provided at the lower part of the precast beam body, and a plurality of prestressing tendons spaced and distributed along a second direction are provided in the prestressing area;

[0008] The prestressing application area is arranged in the first direction between two inflection points of the prefabricated beam body;

[0009] The first direction is the extension direction of the precast beam body, and the second direction is the width direction of the precast beam body.

[0010] In some modified embodiments of the first aspect of the present application, the distance between the end of the prestress application area in the first direction and the corresponding beam end edge is not less than 1.5 times the effective height of the precast beam body.

[0011] In some modified embodiments of the first aspect of the present application,

[0012] The ends of multiple prestressing tendons are provided with anchor end closures;

[0013] Among them, the anchor end closures are formed by grouting with fine aggregate concrete or low-shrinkage mortar.

[0014] In some modified embodiments of the first aspect of the present application,

[0015] A number of longitudinal steel bars and a number of stirrups are arranged in the precast beam body, and stirrup strengthening areas are respectively provided at both beam ends of the precast beam body;

[0016] Among them, the setting range of the stirrup strengthening area in the first direction is not less than 1 / 2 of the beam height of the precast beam body.

[0017] In some modified embodiments of the first aspect of the present application,

[0018] The part of the beam end connector embedded in the precast beam body is the embedded part, and the part of the beam end connector exposed outside the precast beam body is the connection part;

[0019] The beam end connector includes:

[0020] Two first connecting plates, which are oppositely arranged in the third direction;

[0021] A second connecting plate, which is connected between the two first connecting plates and perpendicular to the first connecting plates;

[0022] A plurality of first connection holes are provided on the second connecting plate of the connection part for connecting threaded locking members to lock and fix with the column side connector of the precast column body;

[0023] Among them, the third direction is the height direction of the precast beam body.

[0024] In some modified embodiments of the first aspect of the present application, the opposite surfaces of the two first connecting plates of the embedded part are respectively welded and fixed to the corresponding longitudinal steel bars.

[0025] In some modified embodiments of the first aspect of the present application, the second connecting plate of the embedded part is anchored in the precast beam body through a plurality of stud bolts.

[0026] In some modified embodiments of the first aspect of the present application, a through hole is formed in the second connecting plate of the embedded part along the second direction.

[0027] The second aspect of the present application provides a beam-column connection node structure, which includes: the prestressed concrete beam described above;

[0028] A precast column body, and a column side connector is arranged in the node area of the precast column body for screwing and fixing with the beam end connector of the precast beam body of the prestressed concrete beam.

[0029] In some modified embodiments of the second aspect of the present application,

[0030] It further includes:

[0031] A filling part, which includes:

[0032] A first filling part, which is arranged in a first filling gap between the beam end of the precast beam body and the node area and wraps the beam end connector and the column side connector;

[0033] A second filling part, which is arranged in a second filling gap between the prestress application area of the precast beam body and the node area;

[0034] The outer wall of the filling part is flush with the outer wall of the precast beam body.

[0035] Compared with the prior art, the variable cross-section prestressed concrete beam and the beam-column connection node structure provided by the present application can reduce the cross-sectional area of the prestressed concrete beam by setting a prestress application area and arranging a plurality of prestressing tendons, are applicable to large-span structures, have good economy, aesthetics and space utilization rate, and in the technical solution adopted by the present invention, only the beam end connector of the precast beam body is connected to the precast column body, and the setting range of the prestress application area is located between two inflection points and is not directly connected to the precast column body, which can be distinguished from the groove connection method adopted by the current assembled prestressed concrete structure, that is, it can avoid problems such as the reinforcement of precast components, the dense steel bars in the node area, and a large amount of on-site concrete wet operation, and can achieve the effects of improving construction efficiency, saving energy and reducing emissions, and being beneficial to environmental protection. Description of the Drawings

[0036] By reading the following detailed description with reference to the drawings, the above and other objects, features and advantages of the exemplary embodiments of the present application will become easily understandable. In the drawings, several embodiments of the present application are shown in an exemplary rather than restrictive manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0037] Figure 1Schematically shows a schematic structural view of a variable cross-section prestressed concrete beam provided by an embodiment of the present invention;

[0038] Figure 2 Schematically shows Figure 1 a schematic cross-sectional structure view of section A-A in;

[0039] Figure 3 Schematically shows Figure 1 a schematic cross-sectional structure view of section B-B in;

[0040] Figure 4 Schematically shows Figure 1 a schematic cross-sectional structure view of section C-C in;

[0041] Figure 5 Schematically shows a schematic structural view of the variable cross-section prestressed concrete beam provided by an embodiment of the present invention from another angle;

[0042] Figure 6 Schematically shows a schematic structural view of a beam-column connection joint structure provided by an embodiment of the present invention;

[0043] Explanation of the reference numerals in the drawings:

[0044] 1, precast beam body; 11, prestressed tendon; 12, anchor end sealing; 13, longitudinal steel bar; 14a, first stirrup; 14b, second stirrup; 1a, prestress application area; 1b, stirrup reinforcement area;

[0045] 2, beam end connecting piece; 21, first connecting plate; 22, second connecting plate; 221, first connecting hole; 222, through hole; 23, stud;

[0046] 3, precast column body;

[0047] 4, column side connecting piece;

[0048] 5, threaded locking piece;

[0049] 61, first filling part; 62, second filling part;

[0050] a, first direction; b, second direction; c, third direction. Detailed implementation manners

[0051] Hereinafter, exemplary embodiments of the present disclosure will be described in more detail with reference to the drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art.

[0052] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application shall have the ordinary meanings understood by those skilled in the art to which this application belongs.

[0053] Embodiment 1

[0054] Reference appendix Figure 1 - appendix Figure 5 In Embodiment 1 of the present invention, a variable cross-section prestressed concrete beam is proposed. The variable cross-section prestressed concrete beam includes: a precast beam body 1, and beam end connectors 2 are respectively embedded at two beam ends in its extending direction for screwing and fixing with column side connectors 4 in the joint area of a precast column body 3. A prestress application area 1a is arranged symmetrically about the midpoint of the precast beam body 1 in a first direction a at the lower part of the precast beam body 1. A plurality of prestressing tendons 11 are arranged at intervals in a second direction b within the prestress application area 1a; the range of the prestress application area 1a arranged in the first direction a is located between two inflection points of the precast beam body 1; wherein, the first direction a is the extending direction of the precast beam body 1, and the second direction b is the width direction of the precast beam body 1.

[0055] Specifically, beam end connectors 2 are respectively embedded at two beam ends of the precast beam body 1 of the variable cross-section prestressed concrete beam provided in this embodiment for screwing and fixing with column side connectors 4 embedded in the joint area of the precast column body 3. The screwing and fixing here can be realized by using threaded locking parts 5 such as bolts and nuts, so as to realize the dry connection of beam and column, without the need for temporary supports, formworks and corbels, and without a large amount of wet work, which can save construction time and cost, and is more economical and environmentally friendly. And the variable cross-section precast beam body 1 provided in this embodiment is a prestressed concrete beam. In large-span structures, prestressed concrete can reduce the cross-sectional area of the precast beam body 1, and has good economy, aesthetics and space utilization rate.

[0056] In order to solve the problems existing in the current prefabricated prestressed concrete structures mainly using groove connections, such as the reinforcement protruding from precast components, the dense reinforcement in the joint area, and the large amount of on-site wet concrete work, in the technical solution adopted by the present invention, a prestress application area 1a is provided at the lower part of the precast beam body 1. The prestress application area 1a is used to arrange prestressed tendons 11. The cross-section of the part of the precast beam body 1 corresponding to the prestress application area 1a is larger than the rest, thus forming a variable cross-section beam structure with a changing cross-sectional size. The prestress application area 1a is arranged symmetrically about the midpoint of the precast beam body 1 in the first direction a, which can ensure that the prestress applied by the prestressed tendons 11 is more evenly distributed in the precast beam body 1, helping to improve the bearing capacity and crack resistance of the precast beam body 1. Here, the first direction a refers to the extension direction of the precast beam body 1, that is, the length direction. Further, the setting range of the prestress application area 1a in the first direction a is located between the two inflection points of the precast beam body 1. Here, the inflection point refers to the bending area of the precast beam body 1 after prestress application, and it is also one of the key parts for prestress application. Its function is to form a curvature to resist bending in the precast beam body 1, thereby increasing the stiffness and bearing capacity of the structure. Setting the prestress application area 1a between the two inflection points can enable the precompressive stress generated by the prestressed tendons 11 in this area to effectively resist the tensile stress generated in the precast beam body 1 during the loading process, thereby significantly improving the flexural bearing capacity of the precast beam body 1. Among them, the tensioning of the prestressed tendons 11 can adopt the pretensioning method or the post-tensioning method.

[0057] According to the above, by setting the prestress application area 1a and arranging multiple prestressed tendons 11, the cross-sectional area of the variable cross-section prestressed concrete beam can be reduced, which is applicable to large-span structures, has good economy, aesthetics and space utilization rate. And in the technical solution adopted by the present invention, only the beam end connector 2 of the precast beam body 1 is connected to the precast column body 3, while the setting range of the prestress application area 1a is located between the two inflection points and is not directly connected to the precast column body 3, which can be distinguished from the groove connection method adopted by the current prefabricated prestressed concrete structure, that is, it can avoid the problems existing in this connection method, such as the reinforcement protruding from precast components, the dense reinforcement in the joint area, and the large amount of on-site wet concrete work, and can achieve the effects of improving construction efficiency, energy conservation and emission reduction and being beneficial to environmental protection.

[0058] The multiple prestressed tendons 11 in the prestress application area 1a are spaced apart along the second direction b. Here, the second direction b refers to the width direction of the precast beam body 1. The spacing between adjacent prestressed tendons 11 in this direction is equal. The number of prestressed tendons 11 adopted and the spacing between adjacent prestressed tendons 11 can be calculated and set according to the actual situation.

[0059] Specifically, refer to the appendix Figure 1 and the appendix Figure 5, anchor end caps 12 are provided at the ends of multiple prestressing tendons 11. Through the filling and curing of fine aggregate concrete or low-shrinkage mortar, the anchor end caps 12 can tightly wrap the ends of the prestressing tendons 11 to form effective anchorage. This anchoring effect can prevent the loosening or falling off of the prestressing tendons 11, thereby improving the stability and safety of the overall structure. Moreover, the setting of the anchor end caps 12 can also effectively prevent the prestress loss of the prestressing tendons 11 caused by long-term stress or environmental factors; both fine aggregate concrete and low-shrinkage mortar have high density and impermeability, and can effectively resist the erosion of environmental factors such as moisture and air, thereby protecting the prestressing tendons 11 from corrosion and damage.

[0060] Further, referring to the appendix Figure 1 , in specific implementation, the range of the prestress application area 1a set in the first direction a is not less than 1.5 times the effective height h0 of the precast beam body 1.

[0061] Specifically, in order to further enhance the structural performance of the variable cross-section prestressed concrete beam, in the technical solution adopted by the present invention, between the two inflection points of the precast beam body 1, the distance between the end of the prestress application area 1a in the first direction a and the corresponding beam end edge can be set to be not less than 1.5 times the effective height h0 of the precast beam body 1. Here, the effective height h0 refers to the distance between the resultant force point of the longitudinal tensile reinforcement of the precast beam body 1 and the compression edge of the cross-section. By increasing the setting range of the prestress application area 1a between the two inflection points, a larger prestress application area 1a can be formed in the precast beam body 1, thereby more effectively resisting the bending moment generated by external loads.

[0062] Further, referring to the appendix Figure 1 and the appendix Figure 4 , appendix Figure 5 , in specific implementation, a number of longitudinal steel bars 13 and a number of stirrups are provided in the precast beam body 1, and stirrup strengthening areas 1b are respectively provided at both beam ends of the precast beam body 1; wherein, the setting range of the stirrup strengthening area 1b in the first direction a is not less than half of the beam height h b of the precast beam body 1.

[0063] Specifically, in the technical solution adopted by the present invention, the longitudinal steel bars 13 are the main load-bearing steel bars of the precast beam body 1. The arrangement direction of the longitudinal steel bars 13 is the same as the extension direction of the precast beam body 1, mainly bearing tensile force. The quantity, diameter, etc. of the longitudinal steel bars 13 arranged in the precast beam body 1 need to be determined according to the bearing capacity and span of the precast beam body 1 and comply with the design requirements to ensure that the precast beam body 1 will not be damaged when stressed; the stirrups are the transverse steel bars in the precast beam body 1, arranged along the circumferential direction of the precast beam body 1, used to bear shear force and restrain the lateral deformation of the longitudinal steel bars 13. The setting of the stirrups can also enhance the torsional bearing capacity of the precast beam body 1 and improve the stability of the precast beam body 1; the longitudinal steel bars 13 and the stirrups together form a steel reinforcement cage to jointly bear the load of the precast beam body 1. Among them, the stirrups of the precast beam body 1 include a first stirrup 14a and a second stirrup 14b. The first stirrup 14a is tied outside the longitudinal steel bars 13, and the second stirrup 14b corresponds to the prestress application area 1a and is tied outside the longitudinal steel bars 13 and the prestressing tendons 11.

[0064] Both ends of the precast beam body 1 are parts where the stress is relatively complex and prone to damage. By setting the range of the stirrup strengthening area 1b in the first direction a to be not less than 1 / 2 of the beam height h of the precast beam body 1, it is possible to restrain the lateral expansion of the concrete in the compression zone and prevent the concrete from being crushed under the action of pressure, thereby improving the overall stability and bearing capacity of the precast beam body 1; among them, the embedded part of the beam end connector 2 is located in the stirrup strengthening area 1b of the precast beam body 1. b The overall stability and bearing capacity of the precast beam body 1 can be improved by restraining the lateral expansion of the concrete in the compression zone and preventing the concrete from being crushed under the action of pressure; among them, the embedded part of the beam end connector 2 is located in the stirrup strengthening area 1b of the precast beam body 1.

[0065] Further, referring to Appendix Figure 1 Appendix Figure 5 and Appendix Figure 6 In a specific implementation, the part of the beam end connector 2 embedded in the precast beam body 1 is the embedded part, and the part of the beam end connector 2 exposed outside the precast beam body 1 is the connection part; the beam end connector 2 includes: two first connection plates 21, which are arranged opposite to each other in the third direction c; and a second connection plate 22, which is connected between the two first connection plates 21 and perpendicular to the first connection plates 21; a plurality of first connection holes 221 are provided on the second connection plate 22 of the connection part for connecting a threaded locking member 5 to be locked and fixed with the column side connector 4 of the precast column body 3.

[0066] Specifically, in order to realize the screw connection and fixation between the beam-end connecting member 2 of the precast beam body 1 and the precast column body 3, in the technical solution adopted by the present invention, the beam-end connecting member 2 is divided into an embedded part and a connecting part. The embedded part is embedded inside the beam end of the precast beam body 1, while the connecting part is exposed at the beam end of the precast beam body 1 for connecting with the column-side connecting member 4; the structure of the beam-end connecting member 2 specifically includes: two first connecting plates 21 and a second connecting plate 22 connected between the two first connecting plates 21. The two first connecting plates 21 have the same shape and size, and are arranged oppositely in the third direction c, and they are parallel to each other. Here, the third direction c refers to the height direction of the precast beam body 1; the second connecting plate 22 is vertically connected between the two first connecting plates 21, that is, the beam-end connecting member 2 forms an approximate "I" - shaped structure. A plurality of first connection holes 221 are formed on the second connecting plate 22 corresponding to the connecting part for connecting a threaded locking member 5 to lock and fix with the column-side connecting member 4 of the precast column body 3. Here, the threaded locking member 5 can include, but is not limited to, bolts, nuts, etc.

[0067] Among them, the specific structure of the column-side connecting member 4 of the precast column body 3 is not specifically limited here. Its structure is intended to include a third connecting plate corresponding to and fitting with the second connecting plate 22, and a plurality of second connection holes are provided on the third connecting plate that are in one-to-one correspondence and adaptation with the plurality of first connection holes 221 of the second connecting plate 22, so that the corresponding first connection holes 221 and second connection holes can connect the threaded locking member 5 to realize the locking and fixation between the beam-end connecting member 2 and the column-side connecting member 4.

[0068] Further, referring to the appendix Figure 2 , in specific implementation, the opposite surfaces of the two first connecting plates 21 of the embedded part are respectively welded and fixed to the corresponding longitudinal steel bars 13.

[0069] Specifically, in order to improve the connection strength of the beam-end connecting member 2, in the technical solution adopted by the present invention, the two first connecting plates 21 corresponding to the embedded part can be firmly connected to the longitudinal stirrups by welding to improve the strength of the connection part. Specifically, double-sided lap welding can be adopted, and the welding distance is not less than 5 times the diameter of the steel bar.

[0070] Further, referring to the appendix Figure 1 and the appendix Figure 2 , in specific implementation, the second connecting plate 22 of the embedded part is anchored in the precast beam body 1 through a plurality of stud bolts 23.

[0071] Specifically, in order to more effectively fix the embedded part of the beam-end connector 2 in the precast beam body 1, in the technical solution adopted by the present invention, stud bolts 23 are used as connectors, and the second connecting plate 22 corresponding to the embedded part is anchored in the precast beam body 1 through a plurality of stud bolts 23, which can have higher connection strength and better stability; the number of stud bolts 23 can be four and is distributed in an array. The uniform distribution of the stud bolts 23 can effectively disperse the stress at the connection part and avoid connection failure caused by local stress concentration.

[0072] Among them, referring to the attached Figure 1 , in a specific implementation, the second connecting plate 22 corresponding to the embedded part is provided with through holes 222 along the second direction b. The positions of the through holes 222 can be located at the arrangement center of the plurality of stud bolts 23. By setting the through holes 222, the embedded part of the beam-end connector 2 can be fully and tightly connected to the concrete.

[0073] The following takes the pre-tensioning method of the prestressing tendon 11 as an example to illustrate the production process of the variable cross-section prestressed concrete beam. First, the longitudinal steel bars 13 need to pass through a sufficient number of first stirrups 14a and second stirrups 14b, and then the two ends of the longitudinal steel bars 13 are respectively subjected to double-sided lap welding with the first connecting plate 21 of the beam-end connector 2. After welding, the first stirrups 14a and the second stirrups 14b are moved to the corresponding positions, and the binding of the steel cage is completed; the steel cage is supported at the corresponding position above the prestressing tendon 11. After the prestressing tendon 11 passes through the second stirrup 14b, it is tensioned, the formwork is supported and concrete is poured. When the concrete strength reaches 75%, the bottom formwork is first removed, and then the prestressing tendon 11 is released and cut off. Finally, the sealing end 12 is sealed with fine aggregate concrete or low-shrinkage mortar.

[0074] Embodiment 2

[0075] Referring to the attached Figure 6 , Embodiment 2 of the present invention proposes a beam-column connection joint structure, which includes: the above-mentioned variable cross-section prestressed concrete beam; and a precast column body 3. A column-side connector 4 is provided in the joint area of the precast column body 3 for screwing and fixing with the beam-end connector 2 of the precast beam body 1 of the prestressed concrete beam.

[0076] Specifically, in the technical solution adopted by the present invention, the beam-column connection joint structure includes the above-mentioned variable cross-section prestressed concrete beam and the precast column body 3. The beam end of the variable cross-section prestressed concrete beam is spliced with the joint area of the precast column body 3, and is specifically screwed and fixed through the beam-end connector 2 and the column-side connector 4 to achieve dry connection, and there is no need to set up a temporary support structure, and there is no need for a large amount of wet operations such as on-site concrete pouring, which can save construction time and cost and improve construction efficiency.

[0077] Furthermore, referring to the attached Figure 6, in a specific implementation, the beam-column connection joint structure provided in this embodiment further includes: a filling part, which includes: a first filling part 61, arranged in a first filling gap between the beam end of the precast beam body 1 and the joint area, and wrapping the beam end connector 2 and the column side connector 4; and a second filling part 62, arranged in a second filling gap between the prestress application area 1a of the precast beam body 1 and the joint area; the outer wall of the filling part is flush with the outer wall of the precast beam body 1.

[0078] Specifically, in the technical solution adopted by the present invention, after the beam end connector 2 and the column side connector 4 are connected, there is a first filling gap between the two ends of the precast beam body 1 and the joint area of the precast column body 3. After the beam end connector 2 and the column side connector 4 are reliably screwed, filling material is injected into the first filling gap. Here, the filling material can be fine aggregate concrete to form the first filling part 61, so as to enhance the rigidity and stability of the connection between the beam end connector 2 and the column side connector 4, avoid loosening and damage at the connection, and through the wrapping of the first filling part 61, the beam end connector 2 and the column side connector 4 can be made not to be exposed. The filling material has good corrosion resistance and oxidation resistance, so there is no need for anti-corrosion and fire-proof treatment, which can further reduce the construction cost; to ensure aesthetics, a lightweight filling material is filled in the second filling gap between the prestress application area 1a of the precast beam body 1 and the joint area to form the second filling part 62; the setting of the filling part can make the outer wall of the filling part flush with the outer wall of the precast beam body 1, forming a good appearance.

[0079] When connecting the precast beam body 1 and the precast column body 3, the precast beam body 1 is hoisted to the corresponding position. During connection, the beam end connector 2 and the column side connector 4 are initially tightened by bolts, then the flanges of the beam end connector 2 and the column side connector 4 are welded, and finally the bolts are tightened finally. Then, the stirrups in this section are arranged in the correct position; after the beam end connector 2 and the column side connector 4 are connected, fine aggregate concrete is injected into the first filling gap, and finally a lightweight filling material is filled in the second filling gap. Here, the lightweight filling material needs to meet the fire-proof requirements and needs to be reliably connected to the concrete. Specifically, a special adhesive can be used for connection.

[0080] It should be noted that in the description of this specification, the orientation or positional relationship indicated by terms such as "upper" and "lower" is based on the orientation or positional relationship shown in the drawings. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention; terms such as "connection", "installation", and "fixation" should all be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0081] In the description of this specification, the description of terms such as "one embodiment", "some embodiments", and "specific embodiments" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0082] As described above, the above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A variable cross-section prestressed concrete beam, characterized in that: include: A precast beam body, wherein two beam ends in the extension direction are respectively pre-buried with beam end connectors for being screwed and fixed with column side connectors in the node area of ​​the precast column body, and a prestressing area symmetrically arranged about the midpoint of the precast beam body in the first direction is provided at the lower part of the precast beam body, and a plurality of prestressing tendons spaced and distributed along the second direction are provided in the prestressing area; The prestressing application area is arranged in the first direction between two inflection points of the prefabricated beam body; The first direction is the extension direction of the precast beam body, and the second direction is the width direction of the precast beam body.

2. The variable cross-section prestressed concrete beam according to claim 1, characterized in that: The distance between the end of the prestressing area in the first direction and the corresponding edge of the beam end is not less than 1.5 times the effective height of the prefabricated beam body.

3. The variable cross-section prestressed concrete beam according to claim 1 or 2, characterized in that: The ends of the plurality of prestressed tendons are provided with sealing anchor ends; Wherein, the anchoring end is formed by using fine stone concrete or low shrinkage mortar anchoring.

4. The variable cross-section prestressed concrete beam according to claim 1, characterized in that: A plurality of longitudinal steel bars and a plurality of stirrups are arranged in the precast beam body, and two beam ends of the precast beam body respectively have stirrup reinforcement areas; Wherein, the setting range of the stirrup reinforcement area in the first direction is not less than 1 / 2 of the beam height of the prefabricated beam body.

5. The variable cross-section prestressed concrete beam according to claim 4, characterized in that: The part of the beam end connector embedded in the precast beam body is the embedded part, and the part of the beam end connector exposed outside the precast beam body is the connecting part; The beam end connector comprises: Two first connecting plates, which are arranged opposite to each other in a third direction; A second connecting plate, connected between the two first connecting plates and perpendicular to the first connecting plates; The second connecting plate of the connecting part is provided with a plurality of first connecting holes for connecting a threaded locking member to be locked and fixed with the column side connecting member of the prefabricated column body; Wherein, the third direction is the height direction of the prefabricated beam body.

6. The variable cross-section prestressed concrete beam according to claim 5, characterized in that: The opposite surfaces of the two first connecting plates of the embedded part are respectively welded and fixed to corresponding longitudinal steel bars.

7. The variable cross-section prestressed concrete beam according to claim 5 or 6, characterized in that: The second connecting plate of the embedded part is anchored in the prefabricated beam body by a plurality of bolts.

8. The variable cross-section prestressed concrete beam according to claim 5, characterized in that: The second connecting plate of the embedded part is provided with a through hole along the second direction.

9. A beam-column connection node structure, characterized in that: include: A prestressed concrete beam with a variable cross-section as described in any one of claims 1 to 8; A prefabricated column body, wherein a node area of ​​the prefabricated column body is provided with a column side connector for being screwed and fixed to a beam end connector of the prefabricated beam body of the prestressed concrete beam.

10. The beam-column connection node structure according to claim 9, characterized in that: Also includes: A filling part, comprising: A first filling portion is provided in a first filling gap between the beam end and the node area of ​​the precast beam body and wraps the beam end connector and the column side connector; A second filling portion, provided in a second filling gap between the prestressing application area of ​​the precast beam body and the node area; The outer wall of the filling portion is flush with the outer wall of the prefabricated beam body.

Images