Plastic hinge outward moving type beam column connecting joint

Abstract

The utility model provides a plastic hinge outward moving type beam column connecting joint which comprises a prefabricated column, a cantilever beam is arranged on the side face of the prefabricated column, a prefabricated beam is spliced to the side, away from the prefabricated column, of the cantilever beam, a plastic hinge is formed at the splicing position of the cantilever beam and the prefabricated beam, and connecting profile steel sets are symmetrically installed on the outer side of the splicing position of the cantilever beam and the prefabricated beam. And prestressed steel strands are connected among the prefabricated columns, the cantilever beams and the prefabricated beams. The cantilever beam is arranged on the side face of the prefabricated column to be spliced with the prefabricated beam, outward movement of the plastic hinge is achieved, the connecting profile steel sets are symmetrically installed on the outer side of the splicing position of the cantilever beam and the prefabricated beam, the plastic hinge is formed through yielding energy consumption in the structure bearing process, it is guaranteed that column core area concrete and beam end concrete do not yield, and the main body part of the structure is well protected; and in addition, the prestressed steel strands are arranged, so that certain self-recovery capability can be provided, and meanwhile, normal stress is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of beam-column connections, in particular to a beam-column connection node with an external shifted plastic hinge. Background Technique

[0002] With the rapid development of the construction industry, especially in the fields of high-rise buildings, long-span structures and seismic design, the performance requirements for beam-column connection nodes are increasing day by day. Traditional precast concrete frame structures generally use precast beams, and beams and columns can also be precast simultaneously. According to different connection methods during assembly, precast frame structures can be divided into wet connection frame structures with post-cast parts and fully precast dry connection frame structures. In the wet connection frame structure with post-cast parts, at the assembly splicing joint, the steel bars embedded in the precast beams and columns are butt-jointed by means of welding, bolt sleeve connection and binding, and then concrete is cast on site at the splicing joint to connect the precast beams and columns.

[0003] Since the beams and columns are precast separately, when the beam-column connection node is subjected to external forces such as earthquakes, stress concentration is likely to occur in the connection node area, resulting in cracks and brittle failures of both beams and columns to varying degrees. To solve this problem, the technology of beam-column connection nodes with externally shifted plastic hinges has emerged. This technology changes the force mechanism in the node area and transfers the plastic hinge (i.e., the main part where plastic deformation occurs when the structure is subjected to external forces) from the node area to a position far from the node, thus significantly improving the seismic performance of the structure. However, the external shift of the plastic hinge weakens the energy dissipation capacity of the beam, and the external shift of the plastic hinge does not have a recovery ability. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a beam-column connection node with an externally shifted plastic hinge, which ensures strong columns and weak beams through the external shift of the plastic hinge formed by assembly splicing, and the main body of the structure remains in an elastic state; a large amount of energy dissipation is achieved through the small deformation of the splicing section steel.

[0005] The utility model provides a beam-column connection node with an externally shifted plastic hinge, including a precast column, an overhanging beam is arranged on the side surface of the precast column, a precast beam is spliced on the side of the overhanging beam away from the precast column, a plastic hinge is formed at the splicing joint of the overhanging beam and the precast beam, connection section steel groups are symmetrically installed on the outer side of the splicing joint of the overhanging beam and the precast beam, and prestressed steel strands are connected between the precast column, the overhanging beam and the precast beam.

[0006] Furthermore, through holes corresponding to each other are opened on the precast column, the overhanging beam and the precast beam, and the prestressed steel strands are installed through the through holes.

[0007] Further, the connecting steel section group includes a first steel section, a second steel section and a first steel backing plate. The first steel backing plate is clamped between the first steel section and the second steel section. The first steel section and the cantilever beam, the second steel section and the precast beam, and the first steel section and the second steel section are all fixedly connected by high-strength bolts.

[0008] Further, a number of through holes are provided on both the cantilever beam and the precast beam. Two symmetrically arranged connecting steel section groups are fixedly connected to each other by high-strength bolts passing through the through holes.

[0009] Further, the cross-sections of the first steel section and the second steel section are both L-shaped structures.

[0010] Further, the diameter of the through hole is the same as the diameter of the high-strength bolt.

[0011] Further, stiffening rib plates are equidistantly arranged at the internal corners of the first steel section and the second steel section.

[0012] Further, both ends of the prestressed steel strand are respectively anchored inside adjacent two precast columns.

[0013] Further, second steel backing plates are provided on the side of the first steel section away from the cantilever beam and the side of the second steel section away from the precast beam.

[0014] Further, an adhesive layer is provided between the cantilever beam and the precast beam.

[0015] The beneficial effects of this technical solution are as follows: By splicing a cantilever beam and a precast beam on the side of the precast column, the outward movement of the plastic hinge is realized. And connecting steel section groups are symmetrically installed on the outside of the splicing joint of the cantilever beam and the precast beam, which yield and dissipate energy first during the structural load-bearing, so that the steel sections at the splicing joint of the cantilever beam and the precast beam yield first to form plastic hinges, ensuring that the concrete in the core area of the column and the concrete at the beam end do not yield, well protecting the main part of the structure, and preventing irreversible damage from occurring simultaneously due to the crushing of the concrete at the beam-column connection node. In addition, by setting prestressed steel strands, certain self-recovery ability can be provided, and at the same time, the normal stress can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0017] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0018] Figure 2 This is a schematic diagram of the split structure of the present utility model.

[0019] Explanation of reference numerals in the drawings: 1 - precast column, 2 - cantilever beam, 3 - precast beam, 4 - second section steel, 5 - high-strength bolt, 6 - first steel backing plate, 7 - second steel backing plate, 8 - prestressed steel strand, 9 - through hole, 10 - first section steel. Specific embodiments

[0020] Next, the technical solutions of the present utility model will be clearly and completely described in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present utility model, rather than all of them. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present utility model.

[0021] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0022] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present utility model, "a plurality" means two or more, unless otherwise specifically defined. In addition, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0023] Embodiment 1

[0024] As Figure 1 - Figure 2As shown in the figure, the utility model provides a beam-column connection node with an outward-displaced plastic hinge, which includes a precast column 1. A cantilever beam 2 is arranged on the side of the precast column 1. A precast beam 3 is spliced on the side of the cantilever beam 2 away from the precast column 1. A plastic hinge is formed at the splicing position of the cantilever beam 2 and the precast beam 3. By weakening a specific section in the beam, plastic deformation can be controlled within the beam and fully developed, which can reduce the stress concentration at the beam-end weld. When the structure is subjected to external forces, plastic deformation first occurs at the plastic hinge, absorbing and dissipating a large amount of energy, protecting the joint area from damage, and improving the overall seismic performance of the structure. Connecting steel groups are symmetrically installed on the outer side of the splicing position of the cantilever beam 2 and the precast beam 3. The connecting steel group includes a first steel section 10, a second steel section 4, and a first steel backing plate 6. The cross-sections of the first steel section 10 and the second steel section 4 are both L-shaped structures. The first steel backing plate 6 is clamped between the first steel section 10 and the second steel section 4. The first steel section 10 and the cantilever beam 2, the second steel section 4 and the precast beam 3, and the first steel section 10 and the second steel section 4 are all fixedly connected by high-strength bolts 5. A number of through holes 9 are transversely opened on both the cantilever beam 2 and the precast beam 3. Two mutually symmetric connecting steel groups are fixedly connected to each other through the high-strength bolts 5 passing through the through holes 9, improving the connection strength between the cantilever beam 2 and the precast beam 3.

[0025] By symmetrically installing connecting steel groups on the outer side of the splicing position of the cantilever beam 2 and the precast beam 3, they yield and dissipate energy first when the structure bears loads. Since the steel sections have higher ductility than concrete, the yield deformation of the steel sections at the splicing position can greatly improve the ductility of the joint. At the same time, the efficiency of the steel sections participating in energy dissipation is relatively high, and the joint can show a full hysteretic curve under frequent earthquake loads.

[0026] In order to achieve the stability of pre-tightening after the connecting steel group is connected to the cantilever beam 2 and the precast beam 3, the diameter of the through hole 9 can be set to be the same as the diameter of the high-strength bolt 5 to prevent the high-strength bolt 5 from shaking in the through hole 9.

[0027] Reinforcing rib plates are equally spaced at the internal corners of the first steel section 10 and the second steel section 4, improving the support strength and anti-deformation ability of the first steel section 10 and the second steel section 4.

[0028] Prestressed steel strands 8 are connected between the precast column 1, the cantilever beam 2, and the precast beam 3. Corresponding through holes are opened on the precast column 1, the cantilever beam 2, and the precast beam 3. The prestressed steel strands 8 are installed through the through holes. The two ends of the prestressed steel strands 8 are respectively anchored inside adjacent precast columns 1. In this embodiment, the through holes are arranged at the central positions of the cantilever beam 2 and the precast beam 3. By setting the prestressed steel strands 8, on the one hand, the self-recovery ability of the beam after deformation can be improved, and on the other hand, energy can be dissipated, preventing the damage of the beam and reducing the normal stress.

[0029] After the node proposed by the present utility model experiences a rare earthquake, the plastic deformation of the node is mainly concentrated on the section steel for splicing at the splicing part, while the main beam-column structure remains elastic. After the earthquake, only temporary supports need to be set up, the high-strength bolts at the splicing part are loosened, and the section steel that has fully undergone plastic deformation is removed. At this time, the unbonded prestressed steel strands 8 tensioned in the beam and column can make the node basically return to its original state; then a new batch of high-strength bolts are used to fix a new batch of section steel at the splicing part, and the rapid repair of the node is completed. Since the section steel for splicing is arranged on the side surface of the precast beam, the repair process will not be affected by other structural members such as the floor slab and secondary beam.

[0030] Embodiment 2

[0031] The difference technical features of this embodiment compared with Embodiment 1 are: second steel backing plates 7 are provided on the side of the first section steel 10 away from the cantilever beam 2 and the side of the second section steel 4 away from the precast beam 3. Through the second steel backing plates 7, the pre-tightening force of the high-strength bolts is distributed over a larger area, preventing tearing failure near the through hole 9 caused by stress concentration.

[0032] Embodiment 3

[0033] Compared with Embodiment 1 and Embodiment 2, the difference technical features of this embodiment are: a bonding layer is provided between the cantilever beam 2 and the precast beam 3. The bonding layer is formed by pouring cement mortar. The provision of the bonding layer increases the connection strength between the cantilever beam 2 and the precast beam 3, realizing the complete connection between the cantilever beam 2 and the precast beam 3.

[0034] The construction method of this connection node is as follows:

[0035] (1) Install the precast columns on both sides

[0036] Reserve steel bars on the ground, and in the way of cast-in-place at the column bottom splicing part. Install the precast columns with cantilever beams on both sides of the frame from the bottom. When installing, it is necessary to measure that the distance between the two cantilever beams 2 at both ends is 1-2 cm greater than the length of the precast beam 3, which is convenient for the subsequent splicing of the precast beam 3 and the subsequent tensioning of the prestressed steel strands.

[0037] (2) Conduct preliminary fixation on various components of the beam, column and node

[0038] Lift the precast beam, insert several high-strength bolts into the holes reserved on the first section steel 10, the second section steel 4, the first steel backing plate 6, the second steel backing plate 6, the cantilever beam 2 and the precast beam 3, and then adjust the alignment of the four corner points of the precast column 1 and the precast beam 3 to conduct preliminary fixation on various components of the beam, column and node.

[0039] (3) Tension the prestressed steel strands

[0040] Tensioning devices are arranged on the outer sides of the precast columns on the left and right sides. Along the through holes reserved on the beams and columns, the full-length prestressed steel strands are tensioned and anchored. After the anchoring is completed, the tensioning devices at both ends are removed.

[0041] (4) Finally, tighten the high-strength bolts.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A plastic hinge outward-moving beam-column connection node, characterized in that: It comprises a prefabricated column, a cantilever beam is arranged on the side of the prefabricated column, a prefabricated beam is spliced ​​with the cantilever beam on the side away from the prefabricated column, a plastic hinge is formed at the joint between the cantilever beam and the prefabricated beam, a connecting steel group is symmetrically installed on the outer side of the joint between the cantilever beam and the prefabricated beam, and prestressed steel strands are connected between the prefabricated column, the cantilever beam and the prefabricated beam.

2. The plastic hinge outward displacement beam-column connection node according to claim 1, characterized in that: The prefabricated columns, cantilever beams and prefabricated beams are all provided with through holes corresponding to each other, and the prestressed steel strands are installed through the through holes.

3. The plastic hinge outward displacement beam-column connection node according to claim 1, characterized in that: The connecting steel group includes a first steel, a second steel and a first steel pad, the first steel pad is clamped between the first steel and the second steel, the first steel and the cantilever beam, the second steel and the prefabricated beam, and the first steel and the second steel are all fixedly connected by high-strength bolts.

4. The plastic hinge outward displacement beam-column connection node according to claim 3, characterized in that: The cantilever beam and the prefabricated beam are both provided with a plurality of through holes, and two mutually symmetrical connecting steel groups are fixedly connected to each other by high-strength bolts penetrating the through holes.

5. The plastic hinge outward displacement beam-column connection node according to claim 3, characterized in that: The cross sections of the first steel section and the second steel section are both L-shaped structures.

6. The plastic hinge outward displacement beam-column connection node according to claim 4, characterized in that: The diameter of the through hole is the same as the diameter of the high-strength bolt.

7. The plastic hinge outward-moving beam-column connection node according to claim 5, characterized in that: Reinforcing ribs are evenly spaced at the inner corners of the first steel section and the second steel section.

8. The plastic hinge outward displacement beam-column connection node according to claim 2, characterized in that: The two ends of the prestressed steel strand are respectively anchored inside two adjacent prefabricated columns.

9. The plastic hinge outward-moving beam-column connection node according to claim 3, characterized in that: A second steel pad is provided on a side of the first steel section away from the cantilever beam and a side of the second steel section away from the prefabricated beam.

10. The plastic hinge outward-moving beam-column connection node according to claim 1, characterized in that: An adhesive layer is provided between the cantilever beam and the prefabricated beam.

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