Tongue-groove-steel sleeve-prestress connection anti-bending joint of full-fabricated concrete beam

Abstract

The invention relates to a tongue-and-groove-steel sleeve-prestress connection anti-bending joint for a full-fabricated concrete beam. The tongue-and-groove-steel sleeve-prestress connection anti-bending joint comprises a prefabricated concrete notch beam section, an externally-wrapped thin steel sleeve and post-tensioned prestressed steel bars. The two sections of precast beams are connected into a whole through transverse rabbets at the ends of the beam sections, steel-encased sleeves arranged at the end connecting areas, prestressed steel bars in prestressed ducts and the like to form the node overall connecting rigidity, and the rigidity of the whole-span beam structure and the continuity of internal force transmission are achieved. The technical advantages of flexibility, repeatability, replaceability and the like of tongue-and-groove structures, bolt joints, steel-encased sleeves and prestress connection construction are fully utilized, the comprehensive performance is good, longitudinal stressed steel bars at the beam end of the vertical joint face of the tongue-and-groove are discontinuous and do not appear or are embedded or overlapped, and the problems that in the prior art, the standardization degree is low, the structure is complex, and the construction cost is high can be effectively solved. The problems of low bearing capacity, high assembly precision requirement, high quality control difficulty, poor recoverability, repeatability and replaceability, incapability of adapting to extreme weather conditions and the like are solved.

Description

Technical Field

[0001] This invention relates to the field of prefabricated concrete structure technology in the construction industry, and in particular to a fully prefabricated concrete beam tongue-and-groove-steel sleeve-prestressed connection bending joint. Background Technology

[0002] In recent years, prefabricated modular buildings have been increasingly widely used in public buildings, residential buildings, and other projects. As the main force-transmitting component connecting structural columns and floor slabs in a floor system, beams are usually prefabricated in sections and assembled in segments. The disassembly scheme and connection form are key technical issues in prefabricated beam structures, which have a significant impact on the safety, economy, construction, and durability of the entire structure. Reasonable beam joint construction technology is of great significance for improving the construction level of prefabricated beam structures and enhancing project quality, perfecting the design, fabrication, and construction technology of prefabricated modular floor systems, and further enriching the prefabricated structure technology system.

[0003] Precast beam connection bending joints generally require sufficient bearing capacity, connection stiffness and integrity. The beam structure must simultaneously meet the connection requirements between beam and column, beam and slab, etc. The existing precast beam connection bending joints mainly have the following problems: (1) The connection between precast beam and frame column, main beam and secondary beam, etc. is mainly achieved by splitting key structural components or parts such as columns and joints, and using post-casting, sleeve grouting, grout anchoring and other assembly integral joints. The standardization is low, the joint design and manufacturing are complicated, and the construction accuracy requirements are high. Welding and bolting both require pre-embedded connecting parts. The welding process is complicated and irreversible, and the bending stiffness of bolt joints is difficult to guarantee. (2) Precast floor design mostly adopts composite floor structure scheme. Considering the connection with structural columns and other supporting structures as well as composite floor slabs, the construction of composite layers still requires the erection of temporary supports and the binding of steel bars. The construction efficiency is low and it is not conducive to the control of construction period and cost. (3) The amount of wet work on site is large and the work points are scattered. The degree of industrialization is low and the construction environment is complex. It cannot be reused or replaced. It will cause waste of resources if used for temporary buildings with frequent disassembly and assembly needs such as disaster relief and resettlement, construction houses, and storage houses. It is also not suitable for extreme climate areas such as cold, plateau and high altitude. (4) There is a large difference in the age of concrete between the composite layer and the precast layer and the problem of secondary stress. The actual stress state is complex. The bearing capacity of the nodes is greatly affected by the construction quality and there are safety hazards in the node connection. (5) The continuous force transmission of the precast beam is achieved by the connection of longitudinal reinforcing bars. The top and both ends of the composite beam have exposed bars or pre-embedded bars. The shape of the components is complex and not conducive to transportation, stacking and installation.

[0004] To address the shortcomings of the existing technologies, and to achieve the technical goals of simple structure, reliable force transmission, green construction, low-carbon construction, repeatability, and replaceability of precast beam segment connections, it is essential to develop a fully prefabricated concrete beam tongue-and-groove-steel sleeve-prestressed connection bending joint connection structure. Summary of the Invention

[0005] To address the aforementioned problems, the present invention aims to provide a fully prefabricated concrete beam tongue-and-groove-steel sleeve-prestressed connection bending joint. By comprehensively utilizing transverse tongue-and-groove structures at the beam ends, external steel sleeves, and post-tensioning prestressing, a bending joint structure for extending precast concrete beams is assembled. This provides a new technical solution for the standardized design, fabrication, and construction of precast concrete beams, effectively improving construction efficiency, reducing construction costs, and enhancing project quality.

[0006] The technical solution adopted in this invention is as follows: The present invention proposes a fully prefabricated concrete beam tongue-and-groove-steel sleeve-prestressed connection bending joint, comprising a precast concrete notched beam segment, an outer thin steel sleeve, and prestressed steel bars; the precast concrete notched beam segment is straight, with a stepped transverse tongue-and-groove structure at one or both ends of the beam segment, and adjacent precast concrete notched beam segments are tightly joined by end tongue-and-groove overlap; the outer thin steel sleeve tightly wraps around the connection area surface at the ends of adjacent precast concrete notched beam segments; a circular prestressed duct running the entire length is pre-reserved along the axial direction in the precast concrete notched beam segment; the prestressed steel bars are correspondingly arranged in the prestressed duct.

[0007] Furthermore, the horizontal joint surface of the transverse tongue and groove is arranged at 1 / 2 of the beam height, that is, a half-height through groove is left, with a width equal to that of the beam body, to ensure that the cross-sectional shear capacity of two adjacent precast concrete notched beam segments is consistent.

[0008] Furthermore, the precast concrete notched beam segment is provided with side wing structures on one or both sides; a certain number of transverse screw holes are arranged on the top of the precast concrete notched beam segment along the direction perpendicular to the axis; the side wing structures and transverse screw holes are used to support and connect the precast floor slabs, respectively.

[0009] Furthermore, the wing structure is made of concrete or steel.

[0010] Furthermore, the outer thin steel sleeve includes cold-formed thin-walled steel plate A and cold-formed thin-walled steel plate B, a pressure plate, and a high-strength bolt pair. The cold-formed thin-walled steel plate A and cold-formed thin-walled steel plate B are spliced ​​together to form a rectangular sleeve, which is tightly wrapped around the beam body in the connection area of ​​the ends of two adjacent precast concrete notched beam segments. A certain number of screw holes are reserved along the splicing position of each cold-formed thin-walled steel plate. The pressure plate is a rectangular plate with screw holes reserved at the corresponding positions of the cold-formed thin-walled steel plate. Two plates are arranged for each splice to press the cold-formed thin-walled steel plate at the splice position. After the pressure plate is installed in place, it is fastened by the high-strength bolt pair to form circumferential constraint and bending stiffness, restricting the relative misalignment and rotation of the ends of the two beam segments and providing partial connection stiffness.

[0011] Furthermore, the cold-formed thin-walled steel plate A, the cold-formed thin-walled steel plate B, and the edge-pressing steel plate are all made of Q235 grade steel plate.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. The main body of this invention is a fully prefabricated concrete beam structure bending joint, which can be used for both main beam segments and main and secondary beam segments. The tongue and groove position is flexible, dividing the entire beam into three or two segments. The assembly position of the prefabricated beam segment and the supporting structure such as the structural column and main beam is a certain distance away from the core area of ​​the beam-column and main and secondary beam joint, making it easy to ensure the quality of concrete in the connection area and core area.

[0013] 2. This invention achieves continuous bending resistance of the cross section without connecting longitudinal reinforcing bars. The tongue and groove joint is standard, has good versatility, simple structure, reasonable stiffness, efficient force transmission, and simple assembly, reducing the complexity of node design, manufacturing and construction.

[0014] 3. This invention achieves strong connection of beam segment nodes through external thin steel sleeve constraint and prestressed compression, with good integrity, improved crack resistance, restorability, connection stiffness, and seismic bending and shear bearing capacity of frame beams. It utilizes prestress to provide restoring force, without relying on the node itself to dissipate energy, thus reducing the degree of damage.

[0015] 4. The on-site operations involved in this invention mainly include the positioning and installation of metal connectors such as thin steel sleeves for beam end connection areas and tensioning of straight bundled prestressed steel bars. The construction is flexible, the quality is controllable, and it is adaptable to extreme climatic conditions.

[0016] 5. The tongue and groove connections, bolted joints and post-tensioned unbonded prestressed joints used in this invention are all detachable connection methods, which have little environmental impact, are replaceable and repeatable, and are conducive to the whole life cycle management of the structure.

[0017] The technical solution of this invention has significant advantages in terms of construction flexibility, node integrity, connection reliability, recoverability, repeatability, and replaceability. It saves energy and resources and is not limited by the number of building floors or structural form. It can be used for the connection of precast beam structures in low-rise and high-rise prefabricated concrete frames, shear walls, frame-shear walls, frame-tube structures, etc. It effectively solves the problems of low load-bearing capacity, complex structure, low standardization, high assembly precision requirements, difficult quality control, poor replaceability and repeatability, and inability to adapt to extreme climatic conditions in the existing technology.

[0018] Therefore, this invention has promising prospects for widespread application in the standardized construction of precast beam structures, especially in fully prefabricated structures that require consideration of structural, construction, reuse, and component replacement scenarios, which can achieve better economic, environmental, and social benefits. Attached Figure Description

[0019] Figure 1 This is a partial structural schematic diagram of a fully prefabricated concrete beam tongue-and-groove-steel sleeve-prestressed connection bending joint proposed in this invention. Figure 2 This is a schematic diagram of a partial combination of two thin-walled steel plates in the outer thin steel sleeve of the present invention; Figure 3 This is a schematic diagram illustrating the application effect of the present invention.

[0020] In the attached drawings, the following reference numerals are used: 1-1-Precast concrete notched beam segment A; 1-2-Precast concrete notched beam segment B; 2-Side wing structure; 3-Prestressed duct; 4-Transverse bolt hole; 5-1 Cold-formed thin-walled steel plate A; 5-2 Cold-formed thin-walled steel plate B; 6-Screw hole; 7-Pressure edge steel plate; 8-Horizontal joint surface; 9-Vertical joint surface; 10-High-strength bolt pair; 11-Notched beam segment at both ends; 12-Frame column; 13-Column-side cantilever beam segment; 14-Outer thin steel sleeve. Detailed Implementation

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] It should be noted that in the description of this invention, the terms "upper", "lower", "top", "bottom", "one side", "the other side", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not mean that the device or element must have a specific orientation, or be constructed and operated in a specific orientation.

[0023] See appendix Figure 1 The present invention proposes a fully prefabricated concrete beam tongue-and-groove-steel sleeve-prestressed connection bending joint, comprising a precast concrete notched beam segment, an outer thin steel sleeve 14, and post-tensioned prestressed steel bars; the precast concrete notched beam segments are all straight, with one or both ends of the beam segment configured as a two-step stepped transverse tongue and groove; wherein, two adjacent precast concrete notched beam segments (precast concrete notched beam segment A1-1, precast concrete notched beam segment B1-2) are closely spliced ​​by correspondingly overlapping the horizontal joint surface 8 and the vertical joint surface 9 of their respective end tongue and groove; the horizontal joint surface 8 of the stepped tongue and groove is arranged at 1 / 2 of the beam height, that is, leaving a half-height through slot, with a width equal to the beam body, to ensure that the cross-sectional shear capacity of the two adjacent precast concrete notched beam segments is consistent.

[0024] The outer thin steel sleeve 14 tightly wraps around the surface of the connection area at the ends of two adjacent precast concrete notched beam segments; the connection area refers to the node part extending a certain distance beyond the overlap range of two adjacent precast concrete notched beam segments, that is, the node area covered by the outer thin steel sleeve 14. The length of the end connection area is not less than the beam height, and the cross-sectional shape of the beam segment within this range is rectangular, which facilitates the arrangement of the outer thin steel sleeve 14, etc. The cross-sectional shape of the beam segment outside this range is rectangular or a basket-shaped structure with a side wing structure 2 on one side or a side wing structure 2 on both sides.

[0025] The outer thin steel sleeve 14 includes cold-formed thin-walled steel plates A5-1 and B5-2, a pressing steel plate 7, and a high-strength bolt pair 10; wherein, the cold-formed thin-walled steel plates A, B, and the pressing steel plate are all made of Q235 grade steel plates; the cold-formed thin-walled steel plates A5-1 and B5-2 are spliced ​​together at both ends of the joint to form a rectangular sleeve, which is tightly wrapped around the perimeter of the beam and wrapped around the ends of two adjacent precast concrete notched beam segments. In the beam section of the connecting area, each cold-formed thin-walled steel plate has a certain number of screw holes 6 pre-reserved along the splicing position; the pressing steel plate 7 is a rectangular plate, with screw holes pre-reserved at the corresponding positions of the cold-formed thin-walled steel plate, and two plates are arranged for each splice to press the cold-formed thin-walled steel plate section at the splice position. After the pressing steel plate 7 is installed in place, it is fastened by high-strength bolt pairs 10 to form circumferential constraint and bending stiffness, restricting the relative misalignment and rotation of the ends of the two beam sections, and providing partial connection stiffness.

[0026] The thickness of the pressing steel plate 7 is not less than that of the cold-formed thin-walled steel plate, and the position, diameter and number of screw holes in the pressing steel plate 7 are consistent with the reserved screw holes at the joint position of the connected thin-walled steel plate.

[0027] like Figure 2 As shown, the cold-formed thin-walled steel plates A5-1 and B5-2 can be combined in various shapes, including combinations of two L-shaped plates, two U-shaped plates, or a combination of a U-shaped plate and a straight plate. The joints can be located at the corners, sides, or top and bottom surfaces of the beam. Specific selection should consider the spatial conditions of the steel sleeve joint bolt nodes in the beam end connection area, including requirements for the arrangement of partition walls above and below the beam and the connection of precast floor slabs on the beam side.

[0028] The longitudinal reinforcing bars at each of the nine vertical joint surfaces of the precast concrete notched beam segment are discontinuous. Each precast concrete notched beam segment has a fully axially pre-reserved circular prestressed duct 3. These prestressed ducts 3 are symmetrically arranged along the vertical joint surfaces 9 of the tongue and groove, and symmetrically arranged vertically along the horizontal joint surfaces of the tongue and groove, with a minimum of two rows and four ducts. Post-tensioned prestressed reinforcing bars are arranged within these ducts 3, forming symmetrical reinforcement. The beam segments are pressed together by post-tensioning. The prestressed reinforcing bars in each of the nine vertical joint surfaces 3 serve both as connections and repositioning elements, and also as longitudinal reinforcing bars along the top and bottom surfaces of the beam. Applying prestress achieves axial compression between coaxial beam segments, forming axial constraints, limiting relative axial movement between the ends of the two beam segments, providing partial connection stiffness, enabling the joint to withstand tensile stress, and ensuring the integrity required for the beam end joint connection area to normally exert its load-bearing and deformation capacity.

[0029] The outer thin steel sleeve 14 is installed in two stages. The first stage is after the precast concrete notched beam segment is hoisted into place, the outer thin steel sleeve 14 is wrapped around the beam end connection area, and after fine adjustment, the pressure plate 7 and high-strength bolt pair 10 are installed and the bolts are initially tightened. The second stage is after the prestressing reaches the design value to make the beam segment reach the final pressing state and the bolts are finally tightened.

[0030] The precast concrete notched beam segment is provided with a side wing structure 2 on one or both sides; a certain number of transverse screw holes 4 are arranged on the top of the side wall of the precast concrete notched beam segment along the direction perpendicular to the axis; the side wing structure 2 and the transverse screw holes 4 are used to support and connect the precast floor slab, respectively.

[0031] The side wing structure 2 is made of concrete or steel. When the side wing structure 2 is made of concrete, it is integrally cast with the precast beam, and its cross-sectional shape is rectangular or wedge-shaped, etc. The dimensions of the side wing structure 2 meet the requirements for demolding, installation of precast floor slabs, and force transmission during manufacturing. When the side wing structure 2 is made of steel, it is fixed to the side of the beam by anchor bars using hot-rolled ordinary angle steel, channel steel, or welded box-shaped steel components.

[0032] The outer thin steel sleeve 14 is closely attached to the beam surface in the transverse direction, and there is a certain gap between its two ends and the side wing structure 2, which allows the steel sleeve to slide and reset in a limited manner along the beam axis during the deformation process.

[0033] After the main structure is finally formed, fireproof and anti-corrosion coatings and other protective technical measures are taken for steel components such as cold-formed thin-walled steel plates, edge-pressed steel plates 7 and high-strength bolt pairs 10 to improve the fire resistance and durability of the joints.

[0034] The preferred prestressed connection technology is a straight-line bundle post-tensioned unbonded prestressed scheme. In practice, the appropriate prestressing form can be selected according to the nature of the building, structural characteristics and application conditions, such as using a curved or broken-line bundle form. When there is no need for reuse, the grouting of the ducts forms a partially or completely bonded prestressed prestress, or a partially pre-tensioned bonded prestress, etc.

[0035] Considering the dispersed distribution of longitudinal prestressed steel bars in precast beams, the prestressed steel bars are anchored to the outer surface of the frame column at node 12 using single-hole extrusion anchors. After passing the acceptance test, micro-expansion fine stone concrete is used to protect the exposed steel parts such as prestressed steel bars, tensioning anchors, and wedges.

[0036] This invention connects two precast beams into a whole by means of the tongue and groove structure at the end of the beam segment, the outer thin steel sleeve 14 arranged in the end connection area and the prestressed steel bars in the prestressed duct 3, so as to form the overall connection stiffness of the node and realize the stiffness and continuity of internal force transmission of the whole span beam structure.

[0037] The invention will be further illustrated below through specific application examples: like Figure 3 As shown, this example is a single-frame structure, with precast frame notched beam segments connected to frame columns 12 via several bending joints. Each bending joint includes three precast concrete notched beam segments connected in a straight line. The precast concrete notched beam in the middle area is the two-end notched beam segment 11, meaning both ends of this beam segment are designed with stepped tongue-and-groove joints. The precast concrete notched beams at both ends of the two-end notched beam segments 11 are column-side cantilever beam segments 13, with one end of each column-side cantilever beam segment 13 corresponding to the two-end notched beam segments 11 designed with a corresponding stepped tongue-and-groove joint. The three beam segments are tightly joined together via corresponding tongue-and-groove joints. The main steps in the specific implementation are as follows: (1) First, construct each precast or cast-in-place concrete frame column 12, and cast the cantilever beam segment 13 on the side of the column and the frame column 12 together.

[0038] (2) Install the beam segments 11 with notches at both ends between the columns floor by floor and axis by axis. The tongue and groove of the cantilever beam segments 13 on the column side that have been installed can be used as temporary supports for the beam segments to maintain the stability of the structure during construction and bear the installation load, thereby achieving the free hoisting operation, improving the installation efficiency and saving related measures costs.

[0039] (3) After the necessary adjustments are made to the position of the beam end joint section and the hole, the post-tensioned prestressed steel bars are inserted, and anchors and wedges are installed along the side surface of the frame column 12 and the sleeves are used to tighten them.

[0040] (4) Install thin steel sleeves 14 one by one along the beam end connection area, and temporarily fix each beam segment by initially tightening high-strength bolt pairs.

[0041] Repeat steps (2) to (4) above to install precast beam segments on other axes, including other precast frame beams and secondary beams.

[0042] (5) Using a graded tensioning scheme and intelligent tensioning technology, the prestressed steel bars are tensioned one axis at a time to apply prestress. After tensioning to the design stress level, the bolts are finally tightened.

[0043] Through the above-mentioned fully prefabricated beam joint connection technology, the prefabricated frame beams are connected to the frame columns 12 and the main and secondary beam segments into a whole, so that the beam joints form bending stiffness and can transmit bending moment and shear force. This allows the prefabricated beam segments to be extended without weakening the normal bearing capacity and deformation capacity of the beam structure, thus achieving the design goals of strong connection, detachability, replaceability and repeatability of the bending joints of the prefabricated beam segments.

[0044] It is important to emphasize that beam connection is only one part of the construction of the entire precast floor system. If, in practical applications, after the construction of concrete beams, columns, and other structures is completed, further installation of precast floor slabs is required, the precast beam segments should be hoisted along the other main axis of the column using the same steps. The extension of the precast beam segments in both directions achieves the horizontal load-bearing system's extension within the plane. During precast floor slab installation, the edges or ends of the slab are placed on the upper surface of the side flanges of the surrounding beams, with the top surface of the slab flush with the top of the beam. The slab is then connected to the precast beam as a single unit via bolt joints located at the top of the beam. During the hoisting of precast floor slabs, the side wing structures of the precast beam segments already in place serve as temporary supports for the precast slabs. Starting from the first floor, the upper floor serves as the working platform for the hoisting construction of the next floor. The slabs are hoisted floor by floor and slab by slab until all the precast slabs on all floors are installed. After adjusting the holes and other adjustments to the design position, the bolt joints between the floor slabs and the surrounding beams are installed. The bolts are initially tightened. After all the prestressed steel bars in the precast beams have been tensioned and anchored, the bolt joints at the joints of the precast floor slabs and steel sleeves are finally tightened, so that the overall structure forms the final spatial lateral force resisting system.

[0045] If a building has reached its intended functional purpose and there is a need for recycling for relocation and reinstallation, or replacement of damaged components after an earthquake, the load-bearing elements and finishing layers should be removed first. Then, the connections of the main structural components should be disconnected. Starting from the top floor, following the reverse procedure of the construction process, the entire structure should be dismantled quickly and without damage, floor by floor, in the order of "floor slab - secondary beam - main beam - column". This includes unloading the prestress in the beam structure, removing the outer thin steel sleeves of the beam end connection area, and removing the high-strength bolt pairs between the beam top and the floor slab. The precast slabs, secondary beam sections, main beam sections, and frame columns should be hoisted in sequence. Necessary protective measures should be taken during hoisting, and the components should be classified, numbered, and stored. Generally, if only individual precast components need to be replaced, only the prestress in the beam along the axis of the component to be replaced should be unloaded and the corresponding bolt joints removed. Then, the component should be replaced, and the prestressed steel bars, high-strength bolt pairs, and other connection measures should be reinstalled to restore the normal functional use of the structure.

[0046] Matters not covered in this invention are common knowledge.

[0047] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A fully prefabricated concrete beam tongue-and-groove-steel sleeve-prestressed connection bending joint, characterized in that: It includes precast concrete notched beam segments, an outer thin steel sleeve, and prestressed steel bars; the precast concrete notched beam segments are straight, with a stepped transverse tongue-and-groove structure at one or both ends of the beam segment, and adjacent precast concrete notched beam segments are tightly joined by end tongue-and-groove overlap; the outer thin steel sleeve tightly wraps around the surface of the connection area at the ends of adjacent precast concrete notched beam segments; a circular prestressed duct running through the entire length of the precast concrete notched beam segment is reserved along the axial direction; the prestressed steel bars are correspondingly placed in the prestressed duct.

2. The fully prefabricated concrete beam tongue-and-groove-steel sleeve-prestressed connection bending joint according to claim 1, characterized in that: The horizontal joint surface of the transverse tongue and groove is arranged at 1 / 2 of the beam height, that is, a half-height through groove is left, with a width equal to that of the beam body, to ensure that the cross-sectional shear capacity of two adjacent precast concrete notched beam segments is consistent.

3. The fully prefabricated concrete beam tongue-and-groove-steel sleeve-prestressed connection bending joint according to claim 1, characterized in that: The precast concrete notched beam segment is provided with a wing structure on one or both sides; a certain number of transverse screw holes are arranged on the top of the precast concrete notched beam segment along the direction perpendicular to the axis; the wing structure and the transverse screw holes are used to support and connect the precast floor slab, respectively.

4. The fully prefabricated concrete beam tongue-and-groove-steel sleeve-prestressed connection bending joint according to claim 3, characterized in that: The wing structure is made of concrete or steel.

5. The fully prefabricated concrete beam tongue-and-groove-steel sleeve-prestressed connection bending joint according to claim 1, characterized in that: The outer thin steel sleeve includes cold-formed thin-walled steel plate A and cold-formed thin-walled steel plate B, a pressure plate, and a high-strength bolt pair. The cold-formed thin-walled steel plate A and cold-formed thin-walled steel plate B are spliced ​​together to form a rectangular sleeve, which is tightly wrapped around the beam body in the connection area of ​​the ends of two adjacent precast concrete notched beam segments. A certain number of screw holes are reserved along the splicing position of each cold-formed thin-walled steel plate. The pressure plate is a rectangular plate with screw holes reserved at the corresponding positions of the cold-formed thin-walled steel plate. Two plates are arranged for each splice to press the cold-formed thin-walled steel plate at the splice position. After the pressure plate is installed in place, it is fastened by the high-strength bolt pair to form circumferential constraint and bending stiffness, restricting the relative misalignment and rotation of the ends of the two beam segments and providing partial connection stiffness.

6. The fully prefabricated concrete beam tongue-and-groove-steel sleeve-prestressed connection bending joint according to claim 5, characterized in that: The cold-formed thin-walled steel plate A, cold-formed thin-walled steel plate B, and edge-pressing steel plate are all made of Q235 grade steel plate.

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