Steel secondary beam and concrete main beam connecting structure and construction method thereof

Abstract

The invention provides a connecting structure of a steel secondary beam and a concrete main beam, the connecting structure comprises the concrete main beam and the steel secondary beam, the concrete main beam is provided with an embedding groove, and the embedding groove is the determined space occupied by the part, embedded into the concrete main beam, of the steel secondary beam during design; the secondary steel beams and the webs of the secondary steel beams extend into the embedding grooves to complete embedding, and the main concrete beams and the secondary steel beams are fixed in the embedding grooves through connecting pieces. Compared with the prior art, a direct embedded connecting structure is designed, a multi-element combined structure reinforcing measure is arranged, and an avoiding-resetting process is adopted for manufacturing, so that a bracket and an embedded part in a traditional scheme are omitted, the eccentric problem in the traditional scheme is eliminated, it is ensured that shearing force is directly transmitted to the main beam, additional torque is prevented from being generated on the main beam, and the service life of the main beam is prolonged. The torsion cracking of the main beam is avoided, the durability of the concrete beam is improved, and the stretching of the steel beam is completed before concrete pouring, so that the durability of the structure is improved, and the construction period is shortened.

Description

Technical Field

[0001] This application relates to concrete beam-slab structures, and in particular to a connection structure between a steel secondary beam and a concrete main beam and its construction method. Background Technology

[0002] Industrial buildings typically have numerous equipment and pipelines in the main plant. According to process requirements, equipment and pipelines need to be installed under the main plant floor slab. If a concrete beam-slab structure is used, a large number of embedded parts need to be pre-embedded for later support and hanger installation. The amount of work involved in pre-embedding these parts during construction is enormous, and inaccurate or missed embeddings are highly likely. Therefore, main plant buildings often adopt a concrete frame structure with inserted steel secondary beams and profiled steel sheets as the bottom formwork for the concrete floor slab. This facilitates secondary welding of supports and hangers for equipment and pipelines. Due to the heavy equipment and process loads, the shear force of the steel secondary beams is significant. Therefore, simple embedded parts are used on the sides of the concrete beams (see...). Figure 1 These often fail to meet the load-bearing capacity requirements, necessitating the installation of concrete corbels (see...). Figure 2 The method of supporting the secondary steel beam ensures the safe and reliable transfer of shear force from the beam ends to the main concrete beam. However, the concrete corbel reinforcement includes bent-up bars, transverse stirrups, and main reinforcing bars, making the reinforcement binding complex. The concrete corbel is generally wedge-shaped and varies in size, requiring custom-made irregular-shaped formwork and complex assembly on-site. This results in a cumbersome construction process, long working hours, and high costs. Specifically, the disadvantages of these two connection methods are as follows:

[0003] The scheme of placing the secondary steel beam on the corbel of the main frame beam has the following disadvantages:

[0004] (1) The construction is complicated, time-consuming, and costly. Concrete corbels are generally wedge-shaped and vary in size, requiring complex stirrups, bent-up bars, and load-bearing bars. Custom-made irregular-shaped formwork is also necessary. The construction of tying reinforcing bars and installing formwork is very complicated, time-consuming, and costly. In addition, concrete corbels need 28 days of curing to reach their strength before they can bear loads, which can easily delay the steel structure hoisting progress.

[0005] (2) High precision control requirements. The bracket positioning deviation is large, and the eccentric placement of the secondary beam causes the local bearing pressure of the bracket to exceed the limit; the flatness of the top surface of the bracket is insufficient, and the contact surface between the secondary beam and the bracket is not dense (the actual bearing area is reduced). After installation, the secondary beam tilts and a large number of wedge shims are required for leveling.

[0006] (3) Hidden defects in concrete corbels. Cold joints or honeycomb are prone to appear at the junction of the corbel root and the main beam (due to insufficient vibration in areas with dense reinforcement); concrete holes under the embedded parts are difficult to detect, resulting in insufficient bearing area.

[0007] (4) The eccentric bending moment is large, especially when the main beam is equipped with a corbel on one side.

[0008] However, the method of connecting the steel secondary beam with the embedded parts on the side of the main frame beam has the following disadvantages:

[0009] (1) It is only applicable to structures with a small load range. When the shear force of the steel secondary beam is large, it is difficult to select suitable embedded parts, resulting in a small structural safety margin.

[0010] (2) Higher positioning accuracy is required and the fault tolerance rate is low.

[0011] (3) Welding on the side of concrete beams is detrimental to concrete due to high temperature.

[0012] (4) Increased eccentric bending moment, especially when embedded parts are installed on one side of the main beam.

[0013] (5) Local stress on the embedded parts can easily lead to torsional cracking of the beam.

[0014] Therefore, there is an urgent need for a connection structure that can avoid generating large additional torque on the concrete main beam, reduce torsional cracking of the concrete beam, and improve the safety and durability of the structure. Summary of the Invention

[0015] The purpose of this application is to provide a connection structure that can avoid generating large additional torque on the concrete main beam, reduce torsional cracking of the concrete beam, and improve the safety and durability of the structure.

[0016] This application discloses a connection structure between a steel secondary beam and a concrete main beam. The connection structure includes a concrete main beam and a steel secondary beam. The concrete main beam has an embedding groove, and the steel secondary beam and its web are embedded by extending into the embedding groove. The concrete main beam and the steel secondary beam are fixed in the embedding groove by a connector.

[0017] In a preferred embodiment, the depth of the embedding groove is 150-300 mm.

[0018] In a preferred embodiment, the connector includes reinforcing bars, additional stirrups, and studs.

[0019] In a preferred embodiment, the studs are disposed on both sides of the web of the secondary steel beam extending into the insert groove.

[0020] In a preferred embodiment, the number of studs is 2-6.

[0021] In a preferred embodiment, the stud may be replaced by a short steel bar.

[0022] In a preferred embodiment, the additional stirrups are arranged around the embedded groove.

[0023] In a preferred embodiment, the additional stirrups further include additional stirrups 4 on the side of the steel beam and additional stirrups 4 at the bottom of the steel beam, wherein the additional stirrups on the side of the steel beam are arranged on both sides of the embedded groove, and the additional stirrups at the bottom of the steel beam are arranged at the bottom of the embedded groove.

[0024] In a preferred embodiment, the reinforcing bars are disposed at the bottom of the web of the secondary steel beam.

[0025] In a preferred embodiment, the reinforcing bars include bent-up bars and horizontal additional reinforcing bars.

[0026] In a preferred embodiment, the additional horizontal reinforcement further includes additional horizontal reinforcement at the bottom of the beam and additional horizontal reinforcement at the bottom of the steel beam. The additional horizontal reinforcement at the bottom of the beam is a horizontal reinforcement disposed within the range of the secondary beam and is disposed at the lower part of the secondary beam. The additional horizontal reinforcement at the bottom of the steel beam is a horizontal reinforcement used to cooperate with the additional stirrups at the bottom of the steel beam and is not within the extension range of the secondary beam, i.e., within the groove range.

[0027] In a preferred embodiment, the construction method of the connection structure between the steel secondary beam and the concrete main beam includes the following steps:

[0028] (1) First, during the design phase, an embedded groove is reserved in the concrete main beam, and additional stirrups are pre-configured on both sides of the embedded groove, and horizontal additional reinforcing bars and bent-up reinforcing bars are pre-configured at the bottom;

[0029] (2) Make the additional stirrups on both sides avoid each other, and extend the steel secondary beam into the concrete main beam to the reserved embedding groove. The web of the steel secondary beam is provided with studs on both sides. After the steel secondary beam is in place, the additional stirrups are reset and the steel secondary beam is tied and fixed.

[0030] (3) Then, conventional steel reinforcement binding and formwork sealing are carried out, and concrete is poured after the concealed works are inspected and accepted.

[0031] Compared with existing technologies, the advantages of this invention are:

[0032] 1) This invention eliminates the corbel, employing direct embedding connections and optimized construction techniques. The secondary steel beam extends directly into the main beam, eliminating the need for external corbels, greatly simplifying the construction process, reducing costs, improving efficiency, and providing more direct positioning with reduced deviations. Furthermore, the proposed "avoidance-reset" rebar reinforcement method simplifies the main beam reinforcement binding, avoids complex operations in the corbel area, and eliminates corbel curing steps. Subsequent construction can proceed directly after the steel beam is in place. Therefore, it significantly improves construction efficiency and accuracy, shortens the construction period, and reduces costs.

[0033] 2) This invention eliminates the need for embedded parts through direct embedding and structural reinforcement measures. Specifically, the steel beam extends directly into the main beam, eliminating the need for pre-embedded parts or welding, and providing shear force transmission paths with shear studs, additional stirrups, etc., thus replacing the function of embedded parts in the prior art. Furthermore, the embedding design of this application ensures direct force transmission and avoids eccentricity. This improves structural reliability and safety, and reduces construction risks.

[0034] 3) Compared with existing technologies, the method of this invention improves both precision and quality: installation deviation is small, leveling is unnecessary, and the quality of concealed works is controllable. It also has wide applicability: especially suitable for heavy-load industrial plants, simplifying pre-embedded components and equipment hoisting, and offering high construction efficiency during implementation: shortening the construction period by more than 30%, eliminating maintenance and complex procedures. Cost reduction: reducing formwork, material, and rework costs, lowering project costs by 10-20%. Furthermore, the final finished structure has high reliability: shear force transmission is direct, eccentric bending moment is small, and the risk of structural defects is reduced.

[0035] The specification of this application contains numerous technical features distributed across various technical solutions. Listing all possible combinations of these technical features (i.e., technical solutions) would make the specification excessively lengthy. To avoid this problem, the various technical features disclosed in the above-described invention, the various technical features disclosed in the following embodiments and examples, and the various technical features disclosed in the accompanying drawings can be freely combined to form various new technical solutions (all of which are considered to have been described in this specification), unless such a combination of technical features is technically infeasible. For example, one example discloses feature A+B+C, and another example discloses feature A+B+D+E. Features C and D are equivalent technical means that serve the same function, and technically only one needs to be used; they cannot be used simultaneously. Feature E can technically be combined with feature C. Therefore, the solution A+B+C+D should not be considered as described because it is technically infeasible, while the solution A+B+C+E should be considered as described. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the connection between the steel beam and the corbel of the concrete beam in the prior art described in the background section;

[0037] Figure 2 This is a front view of the connection between the steel beam and the embedded parts of the concrete beam in the prior art described in the background section;

[0038] Figure 3 This is a side view of the structure of the steel beam extending into the concrete beam according to the present invention;

[0039] Figure 4 This is a front view of the structure described in this invention, where a steel beam extends into a concrete beam.

[0040] Figure label:

[0041] 1-Concrete main beam; 2-Steel secondary beam; 3-Stud; 4-Additional stirrups on the side of the steel beam; 5-Bent-up bars; 6-Additional horizontal bars at the bottom of the beam; 7-Additional horizontal bars at the bottom of the steel beam; 8-Reserved hole; 9-Additional stirrups at the bottom of the steel beam. Detailed Implementation

[0042] Through in-depth research and extensive screening, the inventors have developed a method that, compared with existing technologies, eliminates the eccentricity problem of traditional solutions by designing a directly embedded connection structure, setting up multi-element combination structural reinforcement measures, and adopting an avoidance-reset process. This ensures that shear force is directly transmitted to the main beam, avoids additional torque on the main beam, prevents torsional cracking of the main beam, and improves the durability of the concrete beam.

[0043] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0044] Example

[0045] An embodiment of this application, for example Figures 3 to 4 As shown, a connection structure between a steel secondary beam 2 and a concrete main beam 1 is disclosed. The connection structure includes a concrete main beam 1 and a steel secondary beam 2. The concrete main beam 1 is equipped with an embedding groove, which is the space occupied by the steel secondary beam 2 embedded in the concrete main beam 1 as determined during the design. A pre-drilled hole 8 is provided in the embedding groove for placing the web reinforcement of the concrete beam. The steel secondary beam 2 and its web are embedded by extending into the embedding groove. The concrete main beam and the steel secondary beam are fixed in the embedding groove by connectors.

[0046] Optionally, in one embodiment, the depth of the embedding groove is 150-300 mm.

[0047] Optionally, in one embodiment, the connector includes reinforcing bars, additional stirrups, and studs.

[0048] Optionally, in one embodiment, the studs 3 are disposed on both sides of the web of the secondary steel beam extending into the embedding groove.

[0049] Optionally, in one embodiment, the number of studs 3 is 2-6.

[0050] Alternatively, in one embodiment, the stud may be replaced by a short steel bar.

[0051] Optionally, in one embodiment, the additional stirrups include additional stirrups 4 on the side of the steel beam and additional stirrups 9 at the bottom of the steel beam, which are respectively disposed on both sides and the bottom of the embedded groove.

[0052] Alternatively, in one embodiment, the reinforcing bars are disposed at the bottom of the web of the secondary steel beam 2.

[0053] Optionally, in one embodiment, the reinforcing bars include bent-up bars 5, additional horizontal reinforcing bars 6 at the bottom of the beam, and additional horizontal reinforcing bars 7 at the bottom of the steel beam, with the following structure: Figure 3 and Figure 4As shown, the bent-up bar 5 is an additional lifting bar, which is U-shaped and supports the steel secondary beam 2. The additional horizontal bar 6 at the bottom of the beam is a horizontal bar arranged within the range of the steel secondary beam 2. It is arranged at the bottom of the steel secondary beam 2 to disperse stress. The additional horizontal bar 7 at the bottom of the steel beam is a horizontal bar used to cooperate with the additional stirrups at the bottom of the steel beam. It is not within the extension range of the steel secondary beam 2.

[0054] Optionally, in one embodiment, the additional horizontal reinforcing bar 7 at the bottom of the steel beam is a mid-span reinforcing bar. This embodiment also discloses a construction method for the connection structure between a steel secondary beam and a concrete main beam, namely the "avoidance-reset" process method, which includes the following steps:

[0055] (1) First, an embedded groove is cut in the concrete main beam 1, and the additional stirrups are pre-configured on both sides of the embedded groove, and the horizontal additional steel bar 6 and the bent-up steel bar 5 are pre-configured at the bottom.

[0056] (2) Make the additional stirrups on both sides avoid each other, and extend the steel secondary beam 2 into the concrete main beam 1. The web of the steel secondary beam 2 is provided with studs 3 on both sides. After the steel secondary beam 2 is in place, the additional stirrups are reset and the steel secondary beam 2 is tied and fixed.

[0057] (3) Then, conventional steel reinforcement binding and formwork sealing are carried out, and concrete is poured after the concealed works are accepted, thereby realizing the connection between the steel secondary beam 2 and the concrete main beam 1.

[0058] Compared with the prior art, the method of this application does not require the connection of the secondary beam 2 after the concrete main beam 1 has been poured. Instead, the connection is completed before pouring and the beams are poured together as a whole, which greatly shortens the construction period. Furthermore, there are no external connecting parts or other components, and the connection between the secondary beam 2 and the concrete main beam 1 after molding is also more aesthetically pleasing.

[0059] It should be noted that in this patent application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. In this patent application, if it refers to performing an action according to an element, it means performing the action at least according to that element, including two cases: performing the action only according to that element, and performing the action according to that element and other elements. Expressions such as "multiple," "repeatedly," and "various" include two, two times, two kinds, and more than two, more than two times, and more than two kinds.

[0060] All documents mentioned in this application are considered to be incorporated in their entirety into the disclosure of this application so that they can serve as a basis for modifications if necessary. Furthermore, it should be understood that after reading the foregoing disclosure of this application, those skilled in the art can make various alterations or modifications to this application, and these equivalent forms also fall within the scope of protection claimed in this application.

Claims

1. A connection structure between a steel secondary beam and a concrete main beam, characterized in that, The connection structure includes a concrete main beam and a steel secondary beam. The concrete main beam is equipped with an embedding groove, which is the space occupied by the steel secondary beam embedded in the concrete main beam as determined during the design. The steel secondary beam and its web are embedded by extending into the embedding groove, and the concrete main beam and the steel secondary beam are fixed in the embedding groove by connectors.

2. The connection structure according to claim 1, characterized in that, The depth of the embedding groove is 150-300mm.

3. The connection structure according to claim 1, characterized in that, The connector includes reinforcing bars, additional stirrups, short bars, and studs.

4. The connection structure according to claim 3, characterized in that, The studs are disposed on both sides of the web of the secondary steel beam that extends into the embedded groove.

5. The connection structure according to claim 4, characterized in that, The number of studs is 2-6.

6. The connection structure according to claim 4, characterized in that, The studs can be replaced by short steel bars.

7. The connection structure according to claim 3, characterized in that, The additional stirrups are arranged around the embedded groove.

8. The connection structure according to claim 3, characterized in that, The reinforcing bars are placed at the bottom of the web of the secondary steel beam.

9. The connection structure according to claim 7, characterized in that, The reinforcing bars include bent-up bars and horizontal additional bars.

10. A method for constructing a connection structure between a steel secondary beam and a concrete main beam as described in any one of claims 1-9, characterized in that, The method includes the following steps: (1) First, during the design phase, an embedded groove is reserved in the concrete main beam, and additional stirrups are pre-configured on both sides of the embedded groove, and horizontal additional reinforcing bars and bent-up reinforcing bars are pre-configured at the bottom; (2) Make the additional stirrups on both sides avoid each other, and extend the steel secondary beam into the concrete main beam to the reserved embedding groove. The web of the steel secondary beam is provided with studs on both sides. After the steel secondary beam is in place, the additional stirrups are reset and the steel secondary beam is tied and fixed. (3) Then, conventional steel reinforcement binding and formwork sealing are carried out, and concrete is poured after the concealed works are inspected and accepted.

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