Joint of short webbed truss reinforced concrete composite slab

Abstract

The utility model relates to a kind of connecting joint of short out-joint truss reinforced concrete composite slab, belong to prefabricated building construction technical field.It is used to connect composite slab and support;End portion hook is equipped with in the end of plate bottom stress reinforcement in composite slab, and end portion hook is inserted into stirrup of support reinforcement framework;Upper hook section of anchoring steel bar is hung on the upper row of longitudinal reinforcement of reinforcement framework, and lower bending section, middle bending section and middle straight section of anchoring steel bar are sequentially inserted into inside of stirrup by passing end portion hook, to realize the mechanical anchoring of end portion hook, so that composite slab is fixedly connected with support.The utility model effectively solves the pain point problem that plate bottom stress reinforcement in composite slab is difficult to install due to the length of overhanging is large and cross collision with beam longitudinal reinforcement in construction process, simplifies construction technology, improves construction convenience and construction efficiency;Connecting joint structure is simple, and connecting strength is improved by anchoring steel bar of specific structure.

Description

Technical Field

[0001] This utility model belongs to the field of prefabricated building construction technology, and relates to a connection node of a short-strut truss reinforced concrete composite slab. Background Technology

[0002] In the development of prefabricated buildings, with the continuous research and application of new materials, the forms of prefabricated floor slabs in my country's prefabricated concrete structures are diverse, mainly including precast solid slabs, prestressed concrete hollow slabs, prestressed lightweight aggregate concrete composite slabs, truss reinforced concrete composite slabs, steel pipe truss concrete composite slabs, double-T slabs, precast ribbed floor slabs, and prestressed concrete perforated composite slabs. Currently, composite floor slabs have become the core prefabricated components in prefabricated buildings, with the highest application rate and the easiest implementation. In particular, truss reinforced concrete composite slabs, as the most traditional and familiar type of slab prefabricated component, have advantages such as simple production, fast construction speed, light weight of prefabricated components, saving formwork, lower requirements for hoisting capacity, improved working environment, and good appearance quality. They have been rapidly developed and widely used in my country's prefabricated buildings and have become the preferred component in the prefabricated building technology route.

[0003] The connection structures of reinforced concrete composite slabs are mainly divided into two categories: one is the connection node between the composite slab and the beam or wall support, and the other is the joint connection between precast base slabs. For unidirectional composite slabs, the support connection is divided into end supports and side supports; for bidirectional composite slabs, all four side supports are end supports. Currently, in the precast base slabs of traditional reinforced concrete composite slabs, the bottom reinforcement extends straight outwards from the slab end. The "Technical Specification for Precast Concrete Structures" (JGJ 1-2014) requires that the bottom reinforcement at the slab end extend at least to the centerline of the support and be no less than 5 times the diameter of the bottom reinforcement. In the support connection method, the straight, outward-extending bottom reinforcement of the precast base slab (referred to as "bearded reinforcement") is inserted into the support member to achieve the node connection between the precast base slab and the beam or wall support, forming an effective force transmission and load-bearing mechanism.

[0004] Because the joint connection between the truss reinforced concrete composite slab and the cast-in-place beam support is relatively complex, and the "bearded reinforcement" of the precast base slab has a long overhang (generally ≥100mm), in the cast-in-place reinforced concrete beam support, the overhanged "bearded reinforcement" of the composite slab overlaps with the longitudinal reinforcement, stirrups, and web reinforcement of the beam in multiple directions. This easily leads to collisions between the "bearded reinforcement" of the precast base slab and the already tied reinforcement in the cast-in-place reinforced concrete beam support during installation, causing difficulties in the hoisting and installation of the precast base slab, significantly reducing construction efficiency compared to expectations, and even generally causing problems for projects using composite slabs. The construction period for prefabricated buildings is significantly longer than that of traditional cast-in-place construction, failing to demonstrate the efficiency-enhancing effects of prefabricated construction. Furthermore, investigations revealed that to ensure effective placement and installation of prefabricated base slabs, most construction sites exhibit 90° bends or cuts of reinforcing bars ("bearded reinforcement bars"). After installation, these bent or cut reinforcement bars either fail to return to their original positions, or, although restored after a 90° bend, suffer severe internal damage. This compromises the quality of the joint connections between the bottom reinforcement bars and beam supports, severely impacting the overall load-bearing capacity of the floor slab and the lateral resistance of the main structure, thus negating the cost-saving and efficiency-enhancing benefits of prefabricated construction. Therefore, effectively addressing the collision problem caused by these "bearded reinforcement bars" and improving the connection safety and construction efficiency between the truss reinforced concrete composite slab and support components has become a key issue in the current application and research of traditional composite slabs. Utility Model Content

[0005] In view of this, the purpose of this utility model is to provide a connection node for a short-strut truss reinforced concrete composite slab, so as to solve the problem of anchorage connection between the truss reinforced concrete composite slab and the reinforced concrete cast-in-place beam support.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A connection node for a short-strut truss reinforced concrete composite slab, used to connect the composite slab and the support;

[0008] The support includes a steel reinforcement cage; the steel reinforcement cage includes longitudinal bars arranged in two rows, and also includes a number of stirrups arranged sequentially along the extension direction of the longitudinal bars, the stirrups surrounding the two rows of longitudinal bars;

[0009] The composite slab includes bottom reinforcing bars laid flat; at least one end of the bottom reinforcing bars is provided with an end hook whose bending direction is parallel to the bottom surface of the composite slab, the end hook is placed between two adjacent stirrups and extends to the inside of the stirrups; the end hook is connected to the support through anchoring bars;

[0010] The anchoring reinforcement includes an upper hook section, a middle straight section, a middle bent section, and a lower bent section. The upper hook section is hooked onto the upper row of longitudinal reinforcement bars. The lower bent section, the middle bent section, and the middle straight section pass through the end hook and extend into the inside of the stirrup. The middle bent section and the lower bent section both face the inside of the reinforcement cage to achieve mechanical anchoring of the end hook, thereby fixing the composite slab to the support.

[0011] Optionally, the support is a cast-in-place reinforced concrete beam, and the longitudinal reinforcement is arranged along the extension direction of the cast-in-place beam; the composite slab is a precast reinforced concrete base slab, and the bottom reinforcing bars are laid in both directions and encased in concrete.

[0012] Optionally, the end hook is a 180° bend hook, the inner diameter of the bend is greater than or equal to 2.5 times the diameter of the bottom reinforcing steel bar, and the length of the straight portion of the end hook near the end is greater than or equal to 3 times the diameter of the bottom reinforcing steel bar.

[0013] Optionally, the end hook extends outward from the concrete, and the horizontal projection length of the extended section is greater than or equal to 40mm.

[0014] Optionally, the relationship between the diameter d1 of the anchoring reinforcement and the diameter d2 of the bottom reinforcing reinforcement is: d1 ≥ d2 - 2 mm; the material grade of the anchoring reinforcement is the same as that of the bottom reinforcing reinforcement.

[0015] Optionally, the acute angle between the straight portion at the end of the upper hook section and the straight portion in the middle is less than or equal to 45°; the inner diameter of the bend of the upper hook section is greater than or equal to 4 times the diameter of the anchoring steel bar; and the length of the straight portion at the end of the upper hook section is greater than or equal to 5 times the diameter of the anchoring steel bar.

[0016] Optionally, the length of the straight section in the middle is greater than or equal to 70 mm, and the angle between the straight portion of the bent section in the middle and the obtuse angle of the straight portion in the middle is less than or equal to 135°; the length of the straight portion of the bent section in the middle is greater than or equal to 5 times the diameter of the anchoring steel bar, and greater than or equal to 50 mm.

[0017] Optionally, the obtuse angle between the straight portion of the lower bend and the straight portion of the middle bend is greater than or equal to 135°, and the length of the straight portion of the lower bend is greater than or equal to 5 times the diameter of the anchoring steel bar.

[0018] Optionally, the bending direction of both the upper hook section and the middle bending section is towards the inside of the support.

[0019] The beneficial effects of this utility model are as follows:

[0020] This invention provides a connection node for a short-stretcher truss reinforced concrete composite slab. During construction, it enables efficient and rapid installation between the composite slab and the support, effectively preventing the installation difficulties caused by the large outward extension of the straight bottom reinforcing bars in traditional reinforced concrete composite slabs, which leads to collisions between the outward-extending reinforcing bars and the already secured longitudinal reinforcement of the beam in the support. Simultaneously, anchoring bars are used to mechanically anchor the end hooks, ensuring a fixed connection between the composite slab and the support, effectively improving the connection strength between the composite slab and the cast-in-place reinforced concrete beam. The horizontal projection length of the bottom reinforcing bars of the composite slab is short, at least half the length of traditional methods, making construction and installation more convenient. Installers only need to use pry bars or adjustable movers to accurately install the composite slab, thereby reducing construction difficulty, improving construction efficiency, and enhancing the quality of the connection.

[0021] In this invention, the horizontal projection length of the extended section of the bottom reinforcing steel bar of the composite slab is short, which effectively reduces the technical difficulty of processing, transportation, stacking, and on-site installation. By using the anchoring steel bar of this invention to connect the reinforcing steel bar between the support and the composite slab, construction efficiency and quality can be improved, hoisting machinery usage fees and labor costs can be saved, and material waste and construction delays can be avoided. Compared with other types of solutions, it saves material usage and is more economical.

[0022] Other advantages, objectives, and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination and study, or may be learned from practice of this invention. The objectives and other advantages of this invention can be realized and obtained through the following description. Attached Figure Description

[0023] To make the objectives, technical solutions, and advantages of this utility model clearer, the preferred embodiments of this utility model will be described in detail below with reference to the accompanying drawings, wherein:

[0024] Figure 1 This is a schematic diagram of the connection structure between the support steel reinforcement cage and the composite slab.

[0025] Figure 2 For the detailed drawing of the anchoring reinforcement;

[0026] Figure 3 This is a schematic diagram of the composite plate in this utility model;

[0027] Figure 4 This is a schematic diagram showing the arrangement of the steel reinforcement cage of the support in this utility model before connection;

[0028] Figure 5 for Figure 4 Enlarged view of section A in the image;

[0029] Figure 6 A schematic diagram showing the lateral displacement of the support reinforcement cage during the hoisting and lowering of the composite slab;

[0030] Figure 7 A schematic diagram showing the composite slab after it has been installed and positioned.

[0031] Figure 8 for Figure 7 Enlarged view of a section at point B in the middle;

[0032] Figure 9 Schematic diagram of the anchoring steel bar installation process Figure 1 ;

[0033] Figure 10 Schematic diagram of the anchoring steel bar installation process Figure 2 ;

[0034] Figure 11 for Figure 9 Enlarged view of a section at point C;

[0035] Figure 12 This is a diagram showing the overall construction status of a reinforced concrete composite slab with short outrigger trusses.

[0036] Attached icons: 1. Truss reinforcement, 2. Bottom reinforcement of slab, 3. Concrete, 4. End hooks, 5. Longitudinal reinforcement, 6. Stirrups, 7. Anchor reinforcement, 8. Upper hook section, 9. Middle straight section, 10. Middle bent section, 11. Lower bent section, 12. Composite slab support structure, 13. Cast-in-place beam support structure, 14. Reinforcing timber, 15. Adjustable displacement device, 16. Reinforcing steel cage, 17. Cast-in-place beam formwork, 18. Web reinforcement. Detailed Implementation

[0037] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this utility model. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0038] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the present invention. To better illustrate the embodiments of the present invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0039] In the accompanying drawings of this utility model, the same or similar reference numerals correspond to the same or similar components. In the description of this utility model, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this utility model. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0040] Please see Figures 1-12 This is a connection node for a short-strut truss reinforced concrete composite slab, used to connect the composite slab and the support.

[0041] The support includes a steel reinforcement cage 16 and concrete 3 wrapped around the steel reinforcement cage 16; the steel reinforcement cage 16 includes longitudinal bars 5 arranged in two rows, and the steel reinforcement cage 16 also includes a number of stirrups 6 arranged at intervals along the extension direction of the longitudinal bars 5, the stirrups 6 surrounding the two rows of longitudinal bars 5.

[0042] The composite slab includes bottom reinforcing bars 2 laid flat; at least one end of the bottom reinforcing bars 2 is provided with an end hook 4 with a bending direction parallel to the bottom surface of the composite slab, the end hook 4 is placed between two adjacent stirrups 6 and extends to the inside of the stirrups 6; the end hook 4 is connected to the support through anchoring bars 7.

[0043] The anchoring reinforcement 7 is formed by bending hot-rolled ribbed steel bars at three different angles. The anchoring reinforcement 7 includes an upper hook section 8, a middle straight section 9, a middle bent section 10, and a lower bent section 11. The bending direction of the upper hook section 8 is the same as that of the middle bent section 10. The upper hook section 8 is hooked onto the upper row of longitudinal reinforcement 5. The lower bent section 11, the middle bent section 10, and the middle straight section 9 pass through the end hook 4 and extend into the inside of the stirrup 6. The bending direction of the middle bent section 10 and the lower bent section 11 is towards the inside of the steel reinforcement cage 16 to achieve mechanical anchoring of the end hook 4, so as to fix the composite slab to the support and form an effective force transmission and bearing mechanism.

[0044] The end hook 4 is a 180° bend hook. The inner diameter of the bend is greater than or equal to 2.5 times the diameter of the bottom reinforcing steel bar 2. The length of the straight portion of the end hook 4 near the end is greater than or equal to 3 times the diameter of the bottom reinforcing steel bar 2. The end hook 4 extends outward from the concrete 3 and reaches the bottom reinforcing steel bar 2 inside the support. The horizontal projection length of the extended section is greater than or equal to 40mm.

[0045] The relationship between the diameter d1 of the anchoring rebar 7 and the diameter d2 of the bottom reinforcing rebar 2 is: d1 ≥ d2 - 2 mm; the material grade of the anchoring rebar 7 is the same as that of the bottom reinforcing rebar 2. The acute angle between the end of the straight section of the upper hook segment 8 and the middle straight section 9 is less than or equal to 45°; the inner diameter of the bend of the upper hook segment 8 is greater than or equal to 4 times the diameter of the anchoring rebar 7; the length of the end of the straight section of the upper hook segment 8 is greater than or equal to 5 times the diameter of the anchoring rebar 7. The length of the middle straight section 9 is greater than or equal to 70 mm; the obtuse angle between the straight section of the middle bend segment 10 and the middle straight section 9 is less than or equal to 135°; the length of the straight section of the middle bend segment 10 is greater than or equal to 5 times the diameter of the anchoring rebar 7, and greater than or equal to 50 mm. The obtuse angle between the straight portion of the lower bend section 11 and the straight portion of the middle bend section 10 is greater than or equal to 135°, and the length of the straight portion of the lower bend section 11 is greater than or equal to 5 times the diameter of the anchoring steel bar 7.

[0046] The support is a cast-in-place reinforced concrete beam, with longitudinal reinforcement 5 arranged along the extension direction of the cast-in-place beam; the composite slab is a precast reinforced concrete truss base slab, with the bottom reinforcing steel bars 2 laid flat in both directions, and the truss steel bars 1 set above the bottom reinforcing steel bars 2. After the concrete 3 is poured, the bottom reinforcing steel bars 2 and the lower half of the truss steel bars 1 are encased in concrete 3.

[0047] In some embodiments of this utility model, the straight portion of the middle bending section 10 of the anchoring steel bar 7 is parallel to the straight portion of the upper hook section 8.

[0048] Whether the end of the bottom reinforcing bar 2 in the composite slab is provided with an end hook 4 depends on whether the end on that side is connected to the support.

[0049] In some embodiments of this utility model, a web reinforcement 18 is provided between the upper and lower rows of longitudinal reinforcements 5, and the web reinforcement 18 extends in the same direction as the longitudinal reinforcement 5; the lower bent section 11 of the anchoring reinforcement 7 extends to the inner side of the web reinforcement 18 and is tied to the web reinforcement 18 with tie wire. When the composite slab is subjected to external force and horizontal displacement occurs between it and the support, the lower bent section 11 of the anchoring reinforcement 7 cooperates with the web reinforcement 18 of the support to limit the horizontal displacement of the end hook 4, and further, to limit the entire composite slab, thereby enhancing the connection strength between the composite slab and the support.

[0050] The construction process of this utility model includes the following steps:

[0051] S1. Prefabricate composite slabs in the factory: Process end hooks 4 with a bending angle of 180° at the ends of the bottom reinforcing steel bars 2 in the composite slab. The reserved openings and embedded junction boxes in the composite slab are prefabricated in the factory. The end hooks 4 are placed horizontally relative to the slab surface in the composite slab.

[0052] S2. Support Preparation: Install reinforced concrete cast-in-place beam formwork 7 on the cast-in-place beam support structure 13. Set up reinforcing timber 14 on the outside of the cast-in-place beam formwork 7 and install adjustable shifters 15 on the reinforcing timber 14 to adjust the position of the reinforcing cage 16. Install composite slab support structure 12 between adjacent cast-in-place beam support structures 13. Process and fabricate beam longitudinal reinforcement 5 and beam stirrups 6 according to design requirements. The width of beam stirrups 6 is the beam section width minus at least 45mm, and the height of beam stirrups 6 is the beam section height minus twice the design protective layer thickness. Fix beam stirrups 6 to beam longitudinal reinforcement 5 by tying them every other one to form reinforcing cage 16, and then install reinforcing cage 16 into cast-in-place beam formwork 7.

[0053] S3. Installation and Connection: Transport the composite slab from the factory to the construction site using a crane. Hover it 500mm above the composite slab support structure 12 at the installation position. Use a pry bar or an adjustable mover 15 fixed to the cast-in-place beam support structure 13 to adjust the position of the reinforcing steel cage 16, moving or tilting it away from the composite slab to increase the distance between the reinforcing steel cage 16 and the adjacent composite slab, providing space for the smooth vertical installation of the composite slab. Then, slowly lower the composite slab and place it in the predetermined position on the composite slab support structure 12. Finally, use a pry bar or adjustable mover 15 to readjust the position of the support reinforcing steel cage 16 again, so that the support reinforcing steel cage 16 is reset to the design position, and the end hooks 4 of the bottom reinforcing steel bars 2 extend into the inside of the beam stirrups 6.

[0054] S4. Preparation of anchoring steel bar 7: This step S4 can be carried out simultaneously with the above steps S1 to S3; according to the style and size of anchoring steel bar 7 in the design drawings, hot-rolled ribbed steel bars with a diameter not less than the diameter of the bottom reinforcing steel bar minus 2mm are used. They are processed and shaped by bending at three different angles at the construction site or factory and stored in the silo for later use.

[0055] S5. Installation of anchoring steel bar 7: An anchoring steel bar 7 is set in each end hook 4. The lower bent section 11 of the anchoring steel bar 7 is inserted downward into the end hook 4. The middle bent section 10 and the middle straight section 9 pass through the end hook 4 in sequence until the upper hook section 8 of the anchoring steel bar 7 is hooked on the longitudinal reinforcement 5 of the beam. The intersection of the middle straight section 9 and the middle bent section 10 passes through and is located on the lower side of the lower surface of the end hook 4. Then, the anchoring steel bar 7 is rotated around the longitudinal reinforcement 5 of the beam into the support so that the anchoring steel bar 7 is tightly attached to the inner side of the end of the end hook 4. The anchoring steel bar 7 is then firmly tied to the longitudinal reinforcement 5 of the beam with tie wire.

[0056] S6. Repeat steps S1 to S5 to complete the installation of the remaining composite panels on the entire layer.

[0057] S7. Lay the pre-embedded conduits on the surface of the composite slab, install the truss reinforcement 1 and node connection reinforcement of the composite layer, and finally pour the concrete of the composite layer and beam.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of this technical solution, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A connection node for a short-stretcher truss reinforced concrete composite slab, used to connect the composite slab and the support; characterized in that: The support includes a steel reinforcement cage (16); the steel reinforcement cage (16) includes longitudinal bars (5) arranged in two rows, and also includes a number of stirrups (6) arranged sequentially along the extension direction of the longitudinal bars (5), the stirrups (6) surrounding the two rows of longitudinal bars (5); The composite slab includes bottom reinforcing bars (2) laid flat; at least one end of the bottom reinforcing bars (2) is provided with an end hook (4) with a bending direction parallel to the bottom surface of the composite slab, the end hook (4) is provided between two adjacent stirrups (6) and extends to the inside of the stirrups (6); the end hook (4) is connected to the support through anchoring bars (7); The anchoring steel bar (7) includes an upper hook section (8), a middle straight section (9), a middle bent section (10), and a lower bent section (11) in sequence. The upper hook section (8) is hooked on the upper row of longitudinal bars (5). The lower bent section (11), the middle bent section (10), and the middle straight section (9) pass through the end hook (4) in sequence and extend into the inside of the stirrup (6). The middle bent section (10) and the lower bent section (11) are both facing the inside of the steel reinforcement skeleton (16) to achieve mechanical anchoring of the end hook (4) and fix the composite plate to the support.

2. The connection node of the short-stretcher truss reinforced concrete composite slab according to claim 1, characterized in that: The support is a cast-in-place reinforced concrete beam, and the longitudinal reinforcement (5) is arranged along the extension direction of the cast-in-place beam; the composite slab is a precast reinforced concrete base slab, and the bottom reinforcing steel bars (2) are laid flat in both directions and are wrapped by concrete (3).

3. The connection node of the short-stretcher truss reinforced concrete composite slab according to claim 2, characterized in that: The end hook (4) is a 180° bend hook, the inner diameter of the bend is greater than or equal to 2.5 times the diameter of the bottom reinforcing bar (2), and the length of the straight part of the end hook (4) near the end is greater than or equal to 3 times the diameter of the bottom reinforcing bar (2).

4. The connection node of the short-stretcher truss reinforced concrete composite slab according to claim 3, characterized in that: The end hook (4) extends out of the concrete (3), and the horizontal projection length of the extended section is greater than or equal to 40mm.

5. The connection node of the short-stretcher truss reinforced concrete composite slab according to claim 1, characterized in that: The relationship between the diameter d1 of the anchoring steel bar (7) and the diameter d2 of the bottom reinforcing steel bar (2) is: d1 ≥ d2 - 2 mm.

6. The connection node of the short-stretcher truss reinforced concrete composite slab according to claim 1, characterized in that: The acute angle between the straight portion at the end of the upper hook section (8) and the middle straight section (9) is less than or equal to 45°; the inner diameter of the bend of the upper hook section (8) is greater than or equal to 4 times the diameter of the anchoring steel bar (7); the length of the straight portion at the end of the upper hook section (8) is greater than or equal to 5 times the diameter of the anchoring steel bar (7).

7. The connection node of the short-stretcher truss reinforced concrete composite slab according to claim 1, characterized in that: The length of the straight section (9) in the middle is greater than or equal to 70 mm, and the obtuse angle between the straight part of the bent section (10) in the middle and the straight section (9) in the middle is less than or equal to 135°; the length of the straight part of the bent section (10) in the middle is greater than or equal to 5 times the diameter of the anchoring steel bar (7) and is greater than or equal to 50 mm.

8. The connection node of the short-stretcher truss reinforced concrete composite slab according to claim 1, characterized in that: The obtuse angle between the straight portion of the lower bent section (11) and the straight portion of the middle bent section (10) is greater than or equal to 135°, and the length of the straight portion of the lower bent section (11) is greater than or equal to 5 times the diameter of the anchoring steel bar (7).

9. The connection node of the short-stretcher truss reinforced concrete composite slab according to claim 1, characterized in that: The bending directions of the upper hook section (8) and the middle bending section (10) are both towards the inside of the support.

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