Double-beam and shear wall connecting structure in modular building and construction process

Abstract

The application discloses a double-beam and shear wall connecting structure and construction technology in a modular building, which has two parallelly arranged shear walls and two superposed beams, the superposed beam comprises a prefabricated beam and a beam cast-in-situ concrete layer, the shear wall is provided with an edge component at both ends, part of the steel bars of the superposed beam are anchored into the shear wall, and the anchoring depth is greater than that of the edge component, connecting gaps are arranged between the two shear walls and between the two prefabricated beams, the end part of the prefabricated beam close to the shear wall is provided with a beam end cast-in-situ area, the beam end cast-in-situ area is the position of a plastic hinge, the beam end cast-in-situ areas of the two prefabricated beams are connected, and the concrete of the beam end cast-in-situ area, the beam cast-in-situ concrete layer and the connecting gap is cast on site together. The structure can better guarantee the overall continuity, form a stronger overall connection between the beam and the shear wall, and provide better toughness and ductility.

Description

Technical Field

[0001] This invention belongs to the field of modular building, specifically relating to a double beam and shear wall connection structure and construction process in modular building. Background Technology

[0002] Modular building is an emerging building structure system that has seen rapid development in recent years due to its high prefabrication rate, short construction cycle, and green and low-carbon characteristics. This system uses each room as a modular unit, prefabricating beams, walls, and other components in a factory, transporting them to the site, and assembling them into a complete building using reliable connection methods. It significantly reduces on-site wet work, substantially improves construction efficiency, and reduces construction pollution.

[0003] In modular buildings, the connection performance between module units has a significant impact on the overall structural stress performance. Poor connection may lead to the separation of structural modules, affecting the functionality of the modular building during normal use. At the same time, we also hope that modular buildings have a certain seismic performance, so that the stiffness of the modules is not too large under horizontal seismic loads (too large stiffness will lead to abrupt changes in structural stiffness, which is detrimental to seismic resistance).

[0004] In modular buildings, the connection between module units involves the connection between double beams and shear walls. For example... Figure 5 The diagram shows the existing connection structure between a double beam and a shear wall. The beam is a precast beam 201, and the shear wall is a precast shear wall 100. The precast beam 201 and the precast shear wall 100 are directly connected together, and the reinforcing bars of the precast beam 201 are anchored into the precast shear wall 100.

[0005] The existing double-beam and shear wall connection structure has the following defects: the beams are prefabricated along their entire length, and the prefabricated beams are directly connected to the prefabricated shear walls, resulting in limited strength at the beam-wall connection nodes and creating weak points under stress. Under seismic loading, plastic hinges form at the beam-wall connection nodes, which will dissipate energy through repeated deformation. However, the fully prefabricated construction of both the beams and shear walls leads to insufficient reinforcement anchorage length and weak interlocking force at the connection nodes, severely weakening the energy dissipation capacity of the plastic hinges. Simultaneously, the lack of rigid connections makes it difficult for the beams and shear walls to form an integrated load-bearing system, affecting the structural performance. This contradiction is particularly prominent in current modular buildings—the advantages of factory prefabrication clash with the seismic requirements of the joints, restricting the application of modular buildings in high-intensity seismic zones and limiting the full realization of the performance of prefabricated monolithic structures. Summary of the Invention

[0006] The first objective of this invention is to provide a double-beam and shear wall connection structure in modular buildings.

[0007] The second objective of this invention is to provide a construction process for a double-beam and shear wall connection structure.

[0008] The first objective of this invention is achieved through the following technical solution:

[0009] A modular building structure for connecting double beams and shear walls is characterized by having two shear walls arranged side by side and two composite beams. The composite beams include precast beams and cast-in-place concrete layers. Edge members are provided at both ends of the shear walls. Some of the reinforcing bars of the composite beams are anchored into the shear walls, and the anchoring depth is greater than that of the edge members. Connection gaps are provided between the two shear walls and between the two precast beams. A cast-in-place area is provided at the end of the precast beam near the shear wall. The cast-in-place area at the beam end is the location of the plastic hinge. The cast-in-place areas at the beam ends of the two precast beams are connected. The cast-in-place areas at the beam ends, the cast-in-place concrete layers of the beams, and the concrete of the connection gaps are poured together on site.

[0010] A further technical solution of the present invention is that the length of the cast-in-place area at the beam end is 0.5-1.5 times the height of the composite beam.

[0011] A further technical solution of the present invention is as follows: a thin-shell plate is provided on the outer side of the cast-in-place area at the beam end of the precast beam. The thin-shell plate is prefabricated together with the precast beam in the factory, and the thin-shell plate serves as a template for the cast-in-place area at the beam end when pouring concrete.

[0012] A further technical solution of the present invention is that the reinforcing bars of the composite beam anchored into the shear wall are located inside the horizontal reinforcing bars of the shear wall.

[0013] A further technical solution of the present invention is that the reinforcing bars of the two composite beams located in the cast-in-place area at the beam ends are connected by additional stirrups.

[0014] A further technical solution of the present invention is as follows: the shear wall is a precast shear wall, the longitudinal reinforcement of the precast beam is anchored into the precast shear wall during the precasting process in the factory, and the portion of the longitudinal reinforcement of the precast beam anchored into the precast shear wall passes through the edge members, and a cast-in-place area at the beam end is reserved between the precast beam and the precast shear wall.

[0015] A further technical solution of the present invention is as follows: the shear wall is a cast-in-place shear wall, the longitudinal reinforcement of the precast beam does not extend beyond the end face of the precast beam, the end face of the precast beam is pre-embedded with a threaded sleeve connected to the longitudinal reinforcement, during on-site installation, a cast-in-place area is reserved between the precast beam and the cast-in-place shear wall, the end of the precast beam is connected to the post-inserted steel bar through the threaded sleeve, the post-inserted steel bar is anchored into the cast-in-place shear wall, and the part of the post-inserted steel bar anchored into the cast-in-place shear wall passes through the edge member.

[0016] The second objective of this invention is achieved through the following technical solution:

[0017] A construction process for the aforementioned double-beam and shear wall connection structure is characterized by comprising the following steps:

[0018] S1, precast beams are prefabricated in the factory;

[0019] S2, the precast beams were hoisted into place on site;

[0020] S3, tying the horizontal and vertical reinforcement bars of the cast-in-place shear wall, tying the longitudinal reinforcement bars of the cast-in-place concrete layer of the beam, tying the stirrups of the edge members, connecting the inserted reinforcement bars through threaded sleeves, and connecting additional stirrups in the cast-in-place area at the beam end, wherein the longitudinal reinforcement bars and the inserted reinforcement bars of the cast-in-place concrete layer of the beam extend into the reinforcement bars of the cast-in-place shear wall.

[0021] S4 involves pouring concrete together with the cast-in-place area at the beam end, the cast-in-place concrete layer of the beam, the connection gaps, and the cast-in-place shear wall.

[0022] A further technical solution of the present invention is as follows: In step S3, when the horizontal reinforcement of the shear wall and the stirrups of the edge members reach the bottom height of the precast beam, the binding of the horizontal reinforcement of the shear wall and the stirrups of the edge members is paused. The reinforcing bars are first connected to the precast beam through the threaded sleeve, and then the binding of the remaining horizontal reinforcement of the shear wall and the stirrups of the edge members is completed.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] This invention establishes a cast-in-place area at the end of the precast beam, where the plastic hinge is located. This area will be filled with concrete on-site. The beam end area is typically a critical location for the formation of the plastic hinge. The structure of this invention better ensures overall continuity, creating a stronger integral connection between the beam and the shear wall, providing better toughness and ductility. Furthermore, the two precast beams are cast together at their beam end areas, allowing for better integration and enhancing ductility requirements, thereby increasing the energy dissipation capacity of the plastic hinge zone. Attached Figure Description

[0025] Figure 1 This is a schematic elevation view of the double-beam and shear wall connection structure according to Embodiment 1 of the present invention;

[0026] Figure 2 This is a plan view of the double beam and shear wall connection structure according to Embodiment 1 of the present invention;

[0027] Figure 3 This is a plan view of the modular building according to Embodiment 1 of the present invention;

[0028] Figure 4 This is a schematic elevation view of the double-beam and shear wall connection structure according to Embodiment 2 of the present invention;

[0029] Figure 5 This is a schematic elevation view of an existing double-beam and shear wall connection structure.

[0030] Meaning of the labels in the attached diagram:

[0031] 100-Precast shear wall; 101-Vertical reinforcement; 102-Horizontal reinforcement; 103-Embedded steel pipe; 104-Connecting reinforcement; 105-Stirrups of edge members; 106-Edge member; 200-Composite beam; 201-Precast beam; 202-Cast-in-place concrete layer of beam; 203-Longitudinal reinforcement; 204-Threaded sleeve; 205-Stirrups of composite beam; 206-Thin shell plate; 300-Cast-in-place area at beam end; 400-Partition wall; 500-Connecting joint; 600-Additional stirrups; 700-Cast-in-place shear wall; 800-Post-inserted reinforcement. Detailed Implementation

[0032] The present invention will be further described below with reference to embodiments.

[0033] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are 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 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, they should not be construed as limiting this invention.

[0034] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0035] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0036] Example 1:

[0037] like Figure 1 and Figure 2 The diagram shows a double-beam and shear wall connection structure in a modular building according to this embodiment. It has two shear walls arranged side by side and two composite beams 200. The shear walls in this embodiment are precast shear walls 100. The composite beams include precast beams 201 and cast-in-place concrete layers 202. Connecting gaps 500 are provided between the two shear walls and between the two precast beams 201.

[0038] In the composite beam 200, longitudinal reinforcement 203 is provided in both the precast beam 201 and the cast-in-place concrete layer 202. The lower part of the stirrup 205 of the composite beam is anchored into the precast beam 201, and the upper part is anchored into the cast-in-place concrete layer 202. In this embodiment, the longitudinal reinforcement 203 of the precast beam 201 extends outward from the end.

[0039] The shear wall has edge members 106 at both ends, and horizontal steel bars 102 and vertical steel bars 101 are provided inside the wall body. Horizontal steel bars 102, stirrups, and vertical steel bars 101 are provided inside the edge members 106.

[0040] The precast beam 201 and the precast shear wall 100 are precast together in the factory. The longitudinal reinforcement 203 of the precast beam 201 is anchored into the precast shear wall 100 during factory precasting, thus connecting with the precast shear wall 100. The portion of the longitudinal reinforcement 203 of the precast beam 201 anchored into the precast shear wall 100 passes through the edge member 106, ensuring that the anchorage depth of the reinforcement is greater than that of the edge member 106. Furthermore, the longitudinal reinforcement 203 of the precast beam 201 anchored into the precast shear wall 100 is located inside the horizontal reinforcement 102 of the precast shear wall 100 to ensure the beam's load-bearing capacity. The ends of the longitudinal reinforcement 203 at the cast-in-place concrete layer 202 of the beam are anchored into the precast shear wall 100 during on-site construction, and the anchored portion also passes through the edge member 106 and is located inside the horizontal reinforcement 102 of the precast shear wall 100. The ends of the longitudinal reinforcement 203 that are anchored into the precast shear wall 100 are all bent toward the middle of the shear wall.

[0041] A cast-in-place area 300 is reserved at the end of the precast beam 201 near the precast shear wall 100. This cast-in-place area 300 is the location of the plastic hinge, and its preferred length is 0.5-1.5 times the height of the composite beam 200. The cast-in-place areas 300 of the two precast beams 201 are connected, and also connected to the connection joint 500. The cast-in-place areas 300, the cast-in-place concrete layer 202, and the concrete of the connection joint 500 will be poured together on-site, thus connecting them as a single unit. After pouring, the two precast beams 201 will be joined together at the position of the cast-in-place area 300, allowing them to better integrate, enhancing ductility requirements, and increasing the energy dissipation capacity of the plastic hinge zone.

[0042] In this embodiment, a thin-shell plate 206 is provided on the outer side of the cast-in-place area 300 at the beam end of the precast beam 201. The thin-shell plate 206 is prefabricated together with the precast beam 201 in the factory. The thin-shell plate 206 serves as the outer formwork for the cast-in-place area 300 at the beam end when pouring concrete, thereby simplifying the on-site construction process. There is no need to install the outer formwork of the cast-in-place area 300 at the beam end on-site, and there is no need to dismantle the outer formwork of the cast-in-place area 300 at the beam end after the building is completed.

[0043] In this embodiment, multiple additional stirrups 600 are arranged sequentially along the length of the beams between the reinforcing bars in the cast-in-place area 300 at the beam ends of the two composite beams 200. The additional stirrups 600 are wrapped around the reinforcing bars of the two composite beams 200. The additional stirrups 600 enhance the integrity between the two beams, making the structure equivalent to a single beam at the beam ends.

[0044] In this embodiment, at least one vertically continuous pre-embedded steel pipe 103 is provided at the edge member 106 of the shear wall. A connecting steel bar 104 is inserted into the pre-embedded steel pipe 103, and grouting material is filled inside the pre-embedded steel pipe 103. The upper part of the connecting steel bar 104 extends to the outside for insertion into the pre-embedded steel pipe 103 of the upper shear wall for connection.

[0045] like Figure 3 The diagram shows a modular building with the double-beam and shear wall connection structure of this embodiment. This modular building includes multiple module units, specifically symmetrically arranged module units M-1L and M-1R, symmetrically arranged module units M-2L and M-2R, symmetrically arranged module units M-3L and M-3R, and symmetrically arranged module units M-4L and M-4R, with corridors between the upper and lower module units. Shear walls are located at both ends of module units M-1R and M-2L, and at both ends of module units M-3R and M-4L. This location involves the connection between the double beams and the shear walls, which is the innovative aspect of this invention. A partition wall 400 is installed below the precast beam 201.

[0046] Example 2:

[0047] like Figure 4 As shown, in Embodiment 2, the shear wall is a cast-in-place shear wall 700. The longitudinal reinforcement 203 of the precast beam 201 does not extend beyond the end face of the precast beam 201, facilitating the transportation of the precast beam 201. A threaded sleeve 204 connected to the longitudinal reinforcement 203 is pre-embedded on the end face of the precast beam 201. The end of the precast beam 201 is connected to a post-inserted reinforcing bar 800 on-site via the threaded sleeve 204. Part of the post-inserted reinforcing bar 800 is anchored into the cast-in-place shear wall 700, while the portion anchored into the cast-in-place shear wall 700 passes through the edge member 106, thus connecting the precast beam 201 to the cast-in-place shear wall 700 via the post-inserted reinforcing bar 800. The end of the longitudinal reinforcement 203 of the cast-in-place concrete layer 202 of the beam is anchored into the cast-in-place shear wall 700 on-site, without the need for post-inserted reinforcing bars, and the anchoring depth is through the edge member 106.

[0048] The construction process of the double-beam and shear wall connection structure in this embodiment includes the following steps:

[0049] S1, precast beam 201 is prefabricated in the factory;

[0050] S2, hoist the precast beam 201 into place on site, and reserve a 300mm cast-in-place area at the beam end between the precast beam 201 and the cast-in-place shear wall 700mm;

[0051] S3, tie the horizontal reinforcement 102 and vertical reinforcement 101 of the cast-in-place shear wall 700, tie the longitudinal reinforcement 203 of the cast-in-place concrete layer 202 of the beam, tie the stirrups 105 of the edge members, connect the post-inserted reinforcement 800 through the threaded sleeve 204, and connect the additional stirrups 600 in the cast-in-place area 300 at the beam end, wherein the longitudinal reinforcement 203 and the post-inserted reinforcement 800 of the cast-in-place concrete layer 202 of the beam extend into the reinforcement of the cast-in-place shear wall 700;

[0052] Furthermore, when the horizontal reinforcement 102 of the shear wall and the stirrups 105 of the edge members reach the bottom height of the precast beam 201, the binding of the horizontal reinforcement 102 of the shear wall and the stirrups 105 of the edge members is suspended. First, the rear-inserted reinforcement 800 is connected to the precast beam 201 through the threaded sleeve 204, and then the binding of the remaining horizontal reinforcement 102 of the shear wall and the stirrups 105 of the edge members is completed.

[0053] S4 involves pouring concrete together the cast-in-place area 300 at the beam end, the cast-in-place concrete layer 202 of the beam, the connecting joint 500, and the cast-in-place shear wall 700, thus connecting them into one unit.

[0054] The above embodiments of the present invention are not intended to limit the scope of protection of the present invention. The implementation of the present invention is not limited thereto. All other modifications, substitutions or alterations made to the above structure of the present invention based on the above content of the present invention, in accordance with ordinary technical knowledge and common practice in the field, without departing from the basic technical idea of ​​the present invention, shall fall within the scope of protection of the present invention.

Claims

1. A double beam and shear wall connection structure in a modular building, characterized by: The structure has two shear walls arranged side by side and two superimposed beams, the superimposed beams comprise precast beams and beam cast-in-situ concrete layers, the shear walls are provided with edge components at two ends, part of the steel bars of the superimposed beams are anchored into the shear walls, and the anchoring depth is greater than the edge components, connecting gaps are respectively arranged between the two shear walls and between the two precast beams, end cast-in-situ areas of the precast beams are arranged near the ends of the precast beams, the end cast-in-situ areas are plastic hinge positions, the end cast-in-situ areas of the two precast beams are connected, and the concrete of the end cast-in-situ areas, the beam cast-in-situ concrete layers and the connecting gaps are cast together on site; thin shell plates are arranged on the sides of the end cast-in-situ areas of the precast beams on the outer side, the thin shell plates are precast together with the precast beams in a factory, and the thin shell plates serve as templates for the end cast-in-situ areas when the concrete is cast; at least one vertical and full-length pre-embedded steel pipe is arranged at the edge component of the shear wall, a connecting steel bar is inserted into the pre-embedded steel pipe, and the pre-embedded steel pipe is filled with grouting material, and the upper part of the connecting steel bar extends to the outside for being inserted into the pre-embedded steel pipe of the upper shear wall for connection.

2. The double beam and shear wall connection structure in the modular building according to claim 1, characterized in that: The length of the end cast-in-situ area is 0.5-1.5 times the height of the superimposed beam.

3. The double beam and shear wall connection structure in the modular building according to claim 1, characterized in that: The steel bars of the superimposed beams anchored into the shear walls are located on the inner side of the horizontal steel bars of the shear walls.

4. The double beam to shear wall connection in a modular building of claim 1, wherein: The steel bars of the two superimposed beams located at the end cast-in-situ areas are connected through additional stirrups.

5. The double beam and shear wall connection structure in the modular building according to claim 4, characterized in that: The shear walls are precast shear walls, the longitudinal steel bars of the precast beams are anchored into the precast shear walls when the precast beams are precast in a factory, part of the longitudinal steel bars of the precast beams pass through the edge components, and the end cast-in-situ areas are reserved between the precast beams and the precast shear walls.

6. The double beam and shear wall connection structure in the modular building according to claim 4, characterized in that: The shear walls are cast-in-situ shear walls, the longitudinal steel bars of the precast beams do not extend out of the end faces of the precast beams, threaded sleeves connected with the longitudinal steel bars are pre-embedded in the end faces of the precast beams, the end cast-in-situ areas are reserved between the precast beams and the cast-in-situ shear walls when the precast beams are installed on site, the end portions of the precast beams are connected through the threaded sleeves and then inserted with steel bars, the inserted steel bars are anchored into the cast-in-situ shear walls, and part of the inserted steel bars pass through the edge components.

7. A construction process of the double beam and shear wall connection structure according to claim 6, characterized in that, The method comprises the following steps: S1, the precast beams are precast in a factory; S2, the precast beams are hoisted into place on site; S3, the horizontal steel bars and vertical steel bars of the wall body of the cast-in-situ shear wall are bound, the longitudinal steel bars of the beam cast-in-situ concrete layers are bound, the stirrups of the edge components are bound, the inserted steel bars are connected through the threaded sleeves, and the additional stirrups are connected at the end cast-in-situ areas, wherein part of the longitudinal steel bars of the beam cast-in-situ concrete layers and the inserted steel bars extend into the steel bars of the cast-in-situ shear wall; S4, the end cast-in-situ areas, the beam cast-in-situ concrete layers, the connecting gaps and the cast-in-situ shear walls are cast with concrete.

8. The construction process of claim 7, wherein: In step S3, when the horizontal steel bars of the tied shear wall and the stirrups of the edge component reach the bottom surface height of the prefabricated beam, the tying of the horizontal steel bars of the shear wall and the stirrups of the edge component is suspended, the post-inserted steel bars are connected together with the prefabricated beam through the threaded sleeve, and then the tying of the remaining horizontal steel bars of the shear wall and the stirrups of the edge component is continued to be completed.

Images