Fabricated reinforced concrete primary and secondary beam connecting joint and operation method
By adopting semi-prefabricated and wet-dry bonding technology in the prefabricated concrete main and secondary beam nodes, and using steel plate connection keys and inverted cow leg shear keys, the problem of poor integrity of existing nodes is solved and higher shear resistance is achieved Capacity and structural stability.
Patent Information
- Application Number
- CN202411792496.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-07
- Publication Date
- 2025-02-18
AI Technical Summary
The nodes of the existing prefabricated concrete are poor in integrity, resulting in insufficient stiffness under load, major deformation of the secondary beam, and weak shear resistance of the primary and secondary beams.
The semi-prefabricated primary and secondary beams are adopted and the combination of steel plate connection keys, inverted cow leg shear bonds and post-poured concrete overlap layer is combined to achieve wet and dry connections between primary and secondary beams, enhancing the integrity and shear resistance of nodes.
Through this technical means, the integrity and shear resistance of the main and secondary beam nodes are significantly improved, the risks of bending deformation and cracks of the main beam are reduced, and the load-bearing stability of the structure is enhanced.
Smart Images
Figure CN119466143A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a node structure in the field of prefabricated concrete structures in building engineering construction, and in particular to a prefabricated concrete semi-prefabricated primary and secondary beam connection node structure. Background Art
[0002] At present, the common prefabricated concrete primary and secondary beam nodes are cast-in-one type and shelved type. Both of them have the problem of poor integrity in the connection of primary and secondary beam nodes in prefabricated structures. This is because the primary and secondary beams need to work together to bear the load together. If the integrity of the primary and secondary beams is poor, the stiffness will be insufficient under the load, the secondary beam will deform greatly, and shear cracks will easily occur in the secondary beam, resulting in the main and secondary beams having weak shear capacity and other shortcomings.
[0003] There are two ways to set up the integral pouring type. The first is to set a post-casting strip on the main beam, that is, to set a transverse groove at the connection of the main beam, and the end of the secondary beam is placed on the groove, and concrete is poured again in the groove of the main beam to achieve the connection between the main and secondary beams. The disadvantage of this method is that it causes stress concentration at the connection between the groove and the main beam, poor shear resistance, and cracking or breaking. The second method is to set up a post-cast section on the secondary beam, that is, to reserve a post-cast section at the end of the secondary beam, and use steel bar welding, mechanical connection or anchoring technology to ensure the safety of the node. The disadvantage of this method is that it brings difficulties to transportation and installation.
[0004] The shelving method is to place the prefabricated secondary beam on the corbel or lug set on the side of the main beam to achieve dry assembly connection. This connection method is simple and fast to construct, but its disadvantage is that its integrity and earthquake resistance are relatively poor. Summary of the invention
[0005] The main purpose of the present invention is to overcome the current technical defects, provide a prefabricated primary and secondary beam node with good integrity and force transmission performance, improve the existing shelved primary and secondary beam connection nodes; use semi-prefabricated primary and secondary beams and adopt a dry-wet combination method to achieve the combination of various components into a whole.
[0006] To achieve the above object, the present invention adopts the following technical solutions: An assembled reinforced concrete main and secondary beam connection node, characterized in that the node comprises a semi-prefabricated main beam, a semi-prefabricated secondary beam, a steel plate connection key, an inverted corbel shear key, and a post-cast concrete superposition layer; The side surface of the semi-prefabricated main beam is provided with an inverted corbel shear key flush with the bottom surface of the semi-prefabricated secondary beam, and the inverted corbel shear keys are symmetrically arranged on both sides of the side surface of the semi-prefabricated main beam; The inverted corbel shear key is prefabricated by integrally pouring concrete with steel plate connection keys and oblique tie bars arranged on both sides of the semi-prefabricated main beam, and is used to place the semi-prefabricated secondary beam; The connecting end of the semi-prefabricated secondary beam is provided with an overhanging section, and the semi-prefabricated secondary beam is placed on the connecting key of the steel plate of the semi-prefabricated main beam; The post-cast concrete superimposed layer is arranged outside the semi-prefabricated primary and secondary beams and the semi-prefabricated secondary beams, and the upper longitudinal steel reinforcement skeletons of the two beams are covered by overall secondary concrete pouring to form a post-cast reinforced concrete layer.
[0007] Furthermore, the steel plate connecting keys are welded box-type components, and the steel plate connecting keys are symmetrically arranged on both sides outside the side of the semi-prefabricated main beam.
[0008] Furthermore, the semi-prefabricated secondary beam is connected to the inverted corbel shear key on the outer side of the semi-prefabricated main beam, and is bolted to the steel plate connecting key through the longitudinal reinforcement at the bottom of the semi-prefabricated secondary beam. The longitudinal reinforcement at the bottom of the prefabricated semi-prefabricated secondary beam passes through the steel plate on the side of the steel plate connecting key away from the main beam. A threaded section is provided at the end of the longitudinal reinforcement at the bottom of the semi-prefabricated secondary beam, and the steel plate is clamped with a nut. The inner side of the steel plate on the side of the steel plate connecting key away from the main beam is fixed with double nuts to prevent loosening and falling off, and the outer side is fixed with a single nut. The horizontal reinforcement prefabricated together with the main beam and passing through the main beam corresponds to the longitudinal reinforcement of the semi-prefabricated secondary beam, and threaded sections are provided at both ends of the reinforcement, which are connected to the steel plates on the side of the symmetrical steel plate connecting key close to the main beam, and are all fixed with a single nut.
[0009] Furthermore, the upper surfaces of the semi-prefabricated primary and secondary beams are roughened.
[0010] Furthermore, stirrups of the semi-prefabricated primary and secondary beams are extended from the tops of the semi-prefabricated primary and secondary beams, and are tied and connected with the longitudinal reinforcements of the beams arranged above them, and the upper longitudinal reinforcements of the semi-prefabricated secondary beams are laid on the upper longitudinal reinforcements of the semi-prefabricated primary beams; Furthermore, the semi-prefabricated secondary beam and the semi-prefabricated main beam are overlapped with the outer side inverted corbel shear keys, and the overlapped contact surfaces of the two are flush and tightly fitted.
[0011] Furthermore, the upper and lower bidirectional shear keys formed by the inverted corbel shear key and the post-cast reinforced concrete on the upper side of the semi-prefabricated secondary beam ensure better transmission of shear force and improve the shear resistance of the main and secondary beam nodes.
[0012] Furthermore, the floor deck is a steel truss floor deck, which is placed on a semi-prefabricated secondary beam, and square timber is arranged at the connection to provide temporary support to prevent the floor deck from slipping during construction.
[0013] Furthermore, the longitudinal reinforcement at the bottom of the prefabricated secondary beam is connected to the steel plate connection key to form a dry connection node, and plastering and leveling are used between the longitudinal reinforcement at the bottom of the prefabricated secondary beam and the steel plate connection key for corrosion protection.
[0014] Furthermore, the operating method of the prefabricated reinforced concrete main and secondary beam connection nodes is characterized in that: an inverted inverted corbel shear key flush with the bottom surface of the semi-prefabricated secondary beam is provided outside the plane of the semi-prefabricated main beam, and the inverted corbel shear keys are symmetrically arranged on both sides outside the plane of the semi-prefabricated main beam, and are used to place the semi-prefabricated secondary beams. The connecting end of the semi-prefabricated secondary beam is an extended section, which is in contact with the surface of the inverted corbel shear key of the semi-prefabricated main beam; the stirrups of the semi-prefabricated main and secondary beams are extended from the top of the semi-prefabricated main and secondary beams, and the longitudinal steel bars of the upper main and secondary beams are arranged. After the steel truss floor slab is laid, the structural steel bars of the joints are tied, and the floor slab and the upper side concrete of the semi-prefabricated main and secondary beams are cast as a whole for a second time, so that the semi-prefabricated main and secondary beams and the floor slab form a whole.
[0015] Working principle: The invention discloses a novel assembled reinforced concrete main and secondary beam node, comprising a semi-prefabricated main beam and a semi-prefabricated secondary beam, wherein a post-cast concrete superimposed layer is arranged on the semi-prefabricated main and secondary beams; an inverted inverted corbel shear key flush with the bottom surface of the semi-prefabricated secondary beam is arranged outside the plane of the semi-prefabricated main beam, an inverted corbel-shaped notch is arranged at the connecting end of the semi-prefabricated secondary beam, and the longitudinal steel bars at the bottom of the semi-prefabricated secondary beam are provided with a threaded extension section, so that the longitudinal steel bars at the bottom of the semi-prefabricated secondary beam pass through the steel plate connecting key away from the steel plate of the main beam, and the steel plate is clamped by a nut so that the inverted corbel-shaped notch is fitted with the surface of the corbel shear key of the semi-prefabricated main beam; the stirrups of the semi-prefabricated main and secondary beams all extend from the tops of the semi-prefabricated main and secondary beams, the upper longitudinal steel bars of the main and secondary beams are arranged, the steel truss floor deck is laid, and the joint structural steel bars are tied, and the floor slab and the upper side concrete of the semi-prefabricated main and secondary beams are cast as a whole for a second time, so that the semi-prefabricated main and secondary beams and the floor slab form a whole.
[0016] Beneficial effects: The steel plate connecting key of the present invention inserts the longitudinal steel bars at the bottom of the semi-prefabricated secondary beam into the left and right sides of the semi-prefabricated main beam, and is fastened to the semi-prefabricated main beam by bolt connection, thereby realizing direct force transmission by dry connection without grouting, and can be plastered and leveled for corrosion protection. The same oblique tensioning bars are prefabricated together with the main beam to form an inverted corbel shear key, so that the inverted corbel shear key and the main beam form a whole, and when the shear key is subjected to the upper load, the longitudinal steel bars of the secondary beam can be completely equivalent to cast-in-place continuous penetration, thereby achieving a good overlapping effect of the lower longitudinal steel bars, effectively resisting the stress caused by bending, reducing the bending deformation of the main beam, reducing the generation of cracks, and greatly enhancing the structural integrity and bearing stability. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 A cross-sectional view of a new type of assembled reinforced concrete primary and secondary beam node; Figure 2 A three-dimensional schematic diagram of a new type of assembled reinforced concrete primary and secondary beam node; Figure 3 A new type of assembled reinforced concrete primary and secondary beam node casting secondary beam and steel truss floor slab cross-section; Figure 4A main view of a new type of assembled reinforced concrete primary and secondary beam node steel plate connection key; Figure 5 Side view of a new type of assembled reinforced concrete main and secondary beam node steel plate connection key; Figure 6 A top view of a new type of prefabricated reinforced concrete main and secondary beam node steel plate connection key.
[0018] In the figure: 1. semi-precast main beam; 2. semi-precast secondary beam; 3. inverted corbel shear key; 4. semi-precast main beam extended stirrups; 5. semi-precast secondary beam extended stirrups; 6. semi-precast main and secondary beam top rough surface; 7. post-cast concrete superposition layer; 8. steel truss floor slab; 9. semi-precast main beam upper longitudinal steel bar; 10. semi-precast secondary beam upper longitudinal steel bar; 11. square timber; 12. temporary support; 13. oblique tie bar; 14. steel plate connection key; 15 nut; 16 semi-precast secondary beam bottom longitudinal steel bar; 17. Horizontal steel bar of symmetrical steel plate connector penetrating through precast column; 18 pad. DETAILED DESCRIPTION
[0019] In order to further illustrate the present invention, the following Figure 1-6 The present invention is further illustrated with the schemes in the specific embodiments. In addition, all the connection / connection relationships mentioned in the text do not simply refer to the direct connection of components, but refer to the fact that a better connection structure can be formed by adding or reducing connection accessories according to the specific implementation situation.
[0020] Please see attached Figures 1 to 6 The present invention relates to a novel assembled reinforced concrete primary and secondary beam node, comprising a semi-prefabricated primary beam 1 and a semi-prefabricated secondary beam 2, and a post-cast reinforced concrete laminated layer 7 arranged on the semi-prefabricated primary and secondary beams; The steel plate connecting keys 14 are arranged at symmetrical positions on both sides of the semi-prefabricated main beam 1, the oblique reinforcement 13 is located on the upper side of the steel plate connecting keys 14, and the steel plate connecting keys 14 and the oblique reinforcement 13 are prefabricated with concrete to form an inverted corbel shear key 3, which is prefabricated with the semi-prefabricated main beam 1. The horizontal reinforcement 17 of the symmetrical steel plate connecting piece that runs through the semi-prefabricated column passes through the left and right symmetrical steel plate connecting keys 14, and the nuts 15 are used to lock and clamp the steel plates. Nuts are used to fix the inner and outer sides of the steel plate on the side of the steel plate connecting key 14 away from the main beam.
[0021] The stirrups 4 of the semi-prefabricated main beam and the stirrups 5 of the semi-prefabricated secondary beam are extended from the top of the semi-prefabricated main and secondary beams. The connecting end of the longitudinal reinforcement 16 at the bottom of the semi-prefabricated secondary beam is provided with an extension section. During installation, the semi-prefabricated secondary beam 2 is placed on the inverted inverted bracket shear key 3 of the semi-prefabricated main beam 1, so that the longitudinal reinforcement 16 at the bottom of the semi-prefabricated secondary beam passes through the steel plate connecting key 14 away from the steel plate on the side of the main beam, and the steel plate is locked and clamped with nuts 15. Double nuts are used to fix the inner side of the steel plate on the side of the steel plate connecting key 14 away from the main beam. After laying the steel truss floor deck 8 on the semi-prefabricated secondary beam 2, the structural steel bars are tied to the stirrups of the beam, and the floor slab and the semi-prefabricated main and secondary beams are cast as a whole for the second time. Through the dry-wet combination construction method, the semi-prefabricated main beam 1, the semi-prefabricated secondary beam 2 and the floor deck 8 are combined into a whole.
[0022] In the embodiment of the present invention, Figure 4-6 As shown, the steel plate connecting key 14 is a welded box-type component, and the steel plates on both sides are provided with through holes. The horizontal steel bars 17 of the symmetrical steel plate connecting parts that penetrate through the prefabricated column pass through the holes of the steel plate connecting key 14 on the side of the main beam, and are fixed on the inside by double nuts 15 and pads 18 to prevent the steel plate connecting key 14 from falling off.
[0023] In the embodiment of the present invention, Figure 4-6 As shown, the longitudinal reinforcement 16 at the bottom of the semi-prefabricated secondary beam passes through the hole of the steel plate on one side of the steel plate connecting key 14 away from the main beam, and is fixed on the inner side by a double nut 15 and a pad 18, and fixed on the outer side by a single nut 15, thereby improving the anchoring and reinforcement capacity of the longitudinal reinforcement 16 at the bottom of the semi-prefabricated secondary beam.
[0024] In the embodiment of the present invention, Figure 1 As shown, the upper surface of the semi-prefabricated primary and secondary beams is a rough surface 6, which is used to improve the bonding force and the integrity of the node when the upper concrete is poured as a whole.
[0025] In the embodiment of the present invention, the inverted corbel shear key 3 and the semi-precast main beam 1 are integrally cast and precast, and the semi-precast secondary beam 2 is provided with an inverted corbel-shaped notch. During installation, it is placed on the inverted corbel shear key 3 of the semi-precast main beam 1 and is connected by bolts so that the slope surface of the notch fits tightly with the slope surface of the inverted corbel shear key 3.
[0026] In the embodiment of the present invention, Figure 2 As shown, the upper longitudinal steel bars 9 of the semi-prefabricated main beam and the upper longitudinal steel bars 10 of the semi-prefabricated secondary beam are laid, so that the upper longitudinal steel bars 10 of the semi-prefabricated secondary beam are laid on the semi-prefabricated main beam steel bars 9.
[0027] In the embodiment of the present invention, Figure 3As shown, after laying the floor deck 8 on the secondary beam, the joint structural steel bars are tied, the floor deck adopts the steel truss floor deck 8, the steel truss floor deck is placed on the semi-prefabricated secondary beam, and square wood 11 is set at the connection between the two for temporary support 12 to prevent the steel truss floor deck from slipping during construction. Finally, the post-cast concrete superposition layer 7 is poured.
[0028] In the embodiment of the present invention, the shear key 3 of the semi-prefabricated main beam inverted corbel is fitted with the inverted corbel groove of the semi-prefabricated secondary beam 2 to form an upper and lower bidirectional shear key, which ensures better transmission of shear force. No grouting is required, and force can be transmitted directly. The anti-corrosion effect can be achieved by plastering and leveling, ensuring that the dry connection node of the main and secondary beams has the same structural performance as the cast-in-place concrete node, can resist positive bending moment and negative bending moment well, and improves the integrity of the dry connection node.
[0029] In the embodiment of the present invention, the oblique steel bars 13 are 45 degrees and are provided with hooks, extending into the semi-prefabricated main beam 1 and connected to the longitudinal steel bars 9 on the upper part of the semi-prefabricated main beam.
[0030] In the embodiment of the present invention, the semi-prefabricated main beam 1 is symmetrically arranged on both sides of the outer side, the semi-prefabricated secondary beam 2 bottom longitudinal steel bars pass through the steel plate connecting key 14 away from the steel plate on one side of the main beam, and the end of the semi-prefabricated secondary beam bottom longitudinal steel bars is provided with a threaded section, and the steel plate is locked and clamped by a nut 15, and the inner side is fixed with a double nut to prevent loosening and falling off; the horizontal steel bars 17 that connect the symmetrical steel plate connectors that pass through the prefabricated column are prefabricated in the main beam in advance, and are connected to the steel plate on the side of the symmetrical steel plate connecting key 14 close to the main beam. The steel bars are provided with threaded sections at both ends, and are fixed with double nuts 15; In the embodiment of the present invention, the width of the steel plate connecting key 14 should satisfy 5t, where t is the thickness of the nut, its height is consistent with the width, and its length is consistent with the width of the secondary beam.
[0031] The novel method for operating the assembled reinforced concrete main and secondary beam connection nodes of the present invention is characterized in that: an inverted inverted corbel shear key 3 flush with the bottom surface of the semi-prefabricated secondary beam 2 is provided outside the plane of the semi-prefabricated main beam 1, the inverted corbel shear key 3 is symmetrically arranged on both sides outside the plane of the semi-prefabricated main beam 1, and is used to place the semi-prefabricated secondary beam 2, the semi-prefabricated secondary beam is reserved with an inverted corbel-shaped notch, the connection end of the longitudinal steel bar 16 at the bottom of the semi-prefabricated secondary beam is provided with a threaded extension section, so that it passes through the steel plate connection key 14, and The clamping steel plate is locked by nuts 15, and by tightening the nuts 15, the slope surface of the inverted corbel-shaped groove reserved in the semi-prefabricated secondary beam is fitted with the corbel surface of the semi-prefabricated main beam 1; the stirrups 4 and 5 of the semi-prefabricated main and secondary beams are extended from the top of the semi-prefabricated main and secondary beams 1 and 2, and the upper main and secondary beam longitudinal steel bars 9 and 10 are arranged. After the steel truss floor deck 8 is laid, the joint structural steel bars are tied, and the floor slab and the post-cast concrete superposition layer 7 on the upper side of the semi-prefabricated main and secondary beams are integrally cast, so that the semi-prefabricated main and secondary beams and the floor slab form a whole.
[0032] Obviously, the embodiments described above are only part of the embodiments of the present invention, rather than all of the embodiments. Any other embodiments obtained by technicians in this field based on the embodiments of the present invention without creative work shall fall within the scope of protection of the present invention.
Claims
1. An assembled reinforced concrete primary and secondary beam connection node, characterized in that: The node includes a semi-prefabricated main beam, a semi-prefabricated secondary beam, a steel plate connection key, an inverted corbel shear key, and a post-cast concrete superposition layer; The side surface of the semi-prefabricated main beam is provided with an inverted corbel shear key flush with the bottom surface of the semi-prefabricated secondary beam, and the inverted corbel shear keys are symmetrically arranged on both sides of the side surface of the semi-prefabricated main beam; The inverted corbel shear key is prefabricated by integrally pouring concrete with steel plate connection keys and oblique tie bars arranged on both sides of the semi-prefabricated main beam, and is used to place the semi-prefabricated secondary beam; The connecting end of the semi-prefabricated secondary beam is provided with an overhanging section, and the semi-prefabricated secondary beam is placed on the connecting key of the steel plate of the semi-prefabricated main beam; The post-cast concrete superimposed layer is arranged outside the semi-prefabricated primary and secondary beams and the semi-prefabricated secondary beams, and the upper longitudinal steel reinforcement skeletons of the two beams are covered by overall secondary concrete pouring to form a post-cast reinforced concrete layer.
2. The assembled reinforced concrete primary and secondary beam connection node according to claim 1, characterized in that: The steel plate connecting keys are welded box-type components, and the steel plate connecting keys are symmetrically arranged on both sides outside the side of the semi-prefabricated main beam.
3. The assembled reinforced concrete primary and secondary beam connection node according to claim 1, characterized in that: The semi-prefabricated secondary beam is connected to the inverted corbel shear key on the outside of the semi-prefabricated main beam, and is bolted to the steel plate connecting key through the longitudinal reinforcement at the bottom of the semi-prefabricated secondary beam. The prefabricated longitudinal reinforcement at the bottom of the semi-prefabricated secondary beam passes through the steel plate on the side of the steel plate connecting key away from the main beam. A threaded section is provided at the end of the longitudinal reinforcement at the bottom of the semi-prefabricated secondary beam, and the steel plate is clamped with a nut. The inner side of the steel plate on the side of the steel plate connecting key away from the main beam is fixed with double nuts to prevent loosening and falling off, and the outer side is fixed with a single nut. The horizontal reinforcement prefabricated together with the main beam and passing through the main beam corresponds to the longitudinal reinforcement of the semi-prefabricated secondary beam, and threaded sections are provided at both ends of the reinforcement, which are connected to the steel plates on the side of the symmetrical steel plate connecting key close to the main beam, and are all fixed with a single nut.
4. The assembled reinforced concrete primary and secondary beam connection node according to claim 1, characterized in that: The upper surfaces of the semi-prefabricated primary and secondary beams are rough.
5. The assembled reinforced concrete primary and secondary beam connection node according to claim 1, characterized in that: The stirrups of the semi-precast primary and secondary beams extend from the tops of the semi-precast primary and secondary beams and are connected by binding with the longitudinal reinforcements of the beams arranged above them. The upper longitudinal reinforcements of the semi-precast secondary beams are laid on top of the upper longitudinal reinforcements of the semi-precast primary beams.
6. The assembled reinforced concrete primary and secondary beam connection node as claimed in claim 3, characterized in that: The semi-prefabricated secondary beam is overlapped with the outer side inverted corbel shear key of the semi-prefabricated main beam, and the overlapped contact surfaces of the two are flush and tightly fitted.
7. The assembled reinforced concrete primary and secondary beam connection node according to claim 1, characterized in that: The up-and-down bidirectional shear key formed by the inverted corbel shear key and the post-cast reinforced concrete on the upper side of the semi-prefabricated secondary beam ensures better transmission of shear force and improves the shear resistance of the nodes of the primary and secondary beams.
8. The assembled reinforced concrete primary and secondary beam connection node as claimed in claim 6, characterized in that: The floor deck is a steel truss floor deck, which is placed on semi-prefabricated secondary beams, and square timber is arranged at the connection to provide temporary support to prevent the floor deck from slipping during construction.
9. The assembled reinforced concrete primary and secondary beam connection node as claimed in claim 3, characterized in that: The longitudinal reinforcement at the bottom of the prefabricated secondary beam is connected to the steel plate connection key to form a dry connection node, and plastering and leveling are used between the longitudinal reinforcement at the bottom of the prefabricated secondary beam and the steel plate connection key for corrosion protection.
10. An operating method for a prefabricated reinforced concrete primary and secondary beam connection node according to any one of claims 1 to 9, characterized in that: An inverted corbel shear key flush with the bottom surface of the semi-precast secondary beam is provided outside the plane of the semi-precast main beam. The inverted corbel shear keys are symmetrically arranged on both sides outside the plane of the semi-precast main beam and are used to place the semi-precast secondary beam. The connecting end of the semi-precast secondary beam is an extended section, which is in contact with the inverted corbel surface of the semi-precast main beam. The stirrups of the semi-precast main and secondary beams are extended from the top of the semi-precast main and secondary beams, and the longitudinal steel bars of the upper main and secondary beams are arranged. After the steel truss floor slab is laid, the structural steel bars of the joints are tied, and the floor slab and the upper side concrete of the semi-precast main and secondary beams are cast as a whole, so that the semi-precast main and secondary beams and the floor slab form a whole.