A three parallel ribbing bundled steel bar connecting structure

Abstract

The utility model discloses a three parallel reinforcing steel bars bundle's reinforcing steel bar connecting structure belongs to reinforcing steel bar connecting construction technical field. Including lower three parallel reinforcing steel bars bundle structure and upper three parallel reinforcing steel bars bundle structure still can contain connecting calibration structure. Lower three parallel reinforcing steel bars bundle structure and upper three parallel reinforcing steel bars bundle structure all are formed by three reinforcing steel bars, and all at least one reinforcing steel bar's length is different with other two, and through length difference makes splicing interface staggered distribution, forms specific staggered distance to disperse stress, avoids stress concentration. After the butt joint of both, three reinforcing steel bars splice forms the equal length state, and is fixed as an organic whole through spot welding. Connecting calibration structure is formed by circular ring and connecting rod, can form radial restraint to three parallel reinforcing steel bars bundle's reinforcing steel bar, promotes the butt joint accuracy. The utility model solves the problem of excessive joint and calibration difficulty when three parallel reinforcing steel bars bundle connects in prior art, is especially suitable for cast-in-place concrete structure, need not rely on special grouting sleeve and grouting material, and construction is simple, cost is lower, and the connecting strength is reliable.

Description

Technical Field

[0001] This utility model relates to the field of steel bar connection construction technology, and more specifically, to a steel bar connection structure with three bundles of bar reinforcement. Background Technology

[0002] In civil engineering fields such as building construction and bridge engineering, large-span, heavy-load concrete structures often employ dense reinforcement designs due to stress requirements, leading to crowded rebar layouts and increased construction difficulty. To address this issue, the "jointed reinforcement" configuration method is widely used. Among them, the three-jointed reinforcement bundle (such as a triangular arrangement) combines three rebars into a bundle, reducing the number of rebars while ensuring the structural bearing capacity, thus alleviating the problem of dense reinforcement.

[0003] In existing technologies, the connection methods for three-bar bundles mainly include lap splicing, welding, and grouting:

[0004] Lap splices are suitable for small-diameter steel bars, but for large-diameter triple reinforcing bars, their connection reliability is insufficient, and the lap length is long, taking up a lot of space.

[0005] Welded connections require handling multiple joints, and the dense arrangement of reinforcing bars can make welding operations difficult. Furthermore, the concentration of joints can easily lead to stress concentration, affecting structural safety.

[0006] Grouting connections are suitable for prefabricated structures, such as the fully grouted sleeve disclosed in patent CN107740542A, and the threaded grouting sleeves disclosed in CN202023329230 and CN202011626910. However, they require special sleeves and grouting materials, which are costly, and the grouting materials require a long curing time to solidify, making them unsuitable for the rapid construction needs of cast-in-place concrete structures.

[0007] Furthermore, when connecting three-bar bundles, the accuracy of the butt joint calibration directly affects the connection quality. Existing technologies lack simple calibration tools specifically for three-bar bundles, which makes it easy for the reinforcing bars to shift during the butt joint process, further reducing the reliability of the connection.

[0008] Therefore, for the connection requirements of three-bar bundles in cast-in-place concrete structures, there is an urgent need for a connection structure that can reduce the number of joints, avoid stress concentration, simplify the calibration process, and has a lower cost. Summary of the Invention

[0009] This utility model provides a steel bar connection structure with three bundled bars to solve the technical problems in the prior art where too many joints in the connection of three bundled bars easily lead to stress concentration, difficulty in butt joint calibration, and high cost and long curing time of grouting connection, which are not suitable for cast-in-place concrete structures.

[0010] This utility model provides a steel bar connection structure with three parallel bars bundled together, including a lower three-bar bundled structure and an upper three-bar bundled structure. Both the lower and upper three-bar bundled structures contain three steel bars, and at least one steel bar has a length that is different from the other two steel bars. This length difference allows the splicing interface to be staggered, thereby dispersing the stress and avoiding stress concentration, and improving the overall connection strength. After the lower and upper three-bar bundled structures are joined together, the three steel bars are spliced ​​to form an equal length state, and the two are welded and fixed together to achieve a reliable connection of the three-bar bundled structure and to transfer stress.

[0011] Furthermore, it also includes a connection calibration structure, which is used to achieve docking calibration between the lower three-rib bundle structure and the upper three-rib bundle structure.

[0012] Furthermore, in both the lower three-bar bundled structure and the upper three-bar bundled structure, two steel bars are of the same length, while the third steel bar has a different length.

[0013] Furthermore, in the lower three-bar bundle structure and the upper three-bar bundle structure, the lengths of the three reinforcing bars are different.

[0014] Furthermore, the staggered distance formed by the length difference between steel bars of different lengths shall not be less than 35 times the diameter of the steel bar, and not less than 500 mm.

[0015] Furthermore, the connection calibration structure consists of two rings and three connecting rods of equal length. The three connecting rods are arranged in a ring at equal intervals and staggered according to the arrangement of the three-bar bundle. This can form radial constraints on the three steel bars in the lower and upper three-bar bundle structures respectively, so as to limit the steel bars from shifting during the docking process and realize the positioning and fixing of the three-bar bundle steel bars.

[0016] Furthermore, the inner side of the ring is provided with anti-slip textures or micro-protrusions to enhance the friction with the steel bars in the lower and upper three-bar bundled structures and prevent relative displacement of the steel bars during the docking process.

[0017] Furthermore, the connection calibration structure is made of φ10 steel bars through spot welding.

[0018] Furthermore, the connecting calibration structure is vertically inserted into the lower three-bar bundled structure and then welded and fixed. The upper three-bar bundled structure is vertically inserted into the connecting calibration structure and then fully fits with all the steel bar joints of the lower three-bar bundled structure before being welded and fixed. After welding, the connecting calibration structure is retained in the middle position.

[0019] Furthermore, the connection between the lower three-rib bundle structure and the upper three-rib bundle structure is fixed by spot welding.

[0020] The beneficial effects of this utility model are:

[0021] This utility model discloses a steel bar connection structure with three parallel bars bundled together. Through the coordinated operation of the lower three parallel bars bundled together structure, the upper three parallel bars bundled together structure, and the optional connection calibration structure, a highly efficient and reliable connection of the three parallel bars bundled together is achieved.

[0022] The lower three-bar bundle structure and the upper three-bar bundle structure adopt a design with at least one bar of different length, so that the splicing interface is staggered, stress is dispersed and stress concentration is avoided, which solves the strength problem caused by the dense welded joints in traditional methods. After the butt joint is connected, it is fixed into a whole by spot welding to form a three-bar bundle of equal length, ensuring the effective transmission of force.

[0023] The connection calibration structure consists of a ring and a connecting rod, which can form a radial constraint on the reinforcing bars, limit the docking offset, improve calibration efficiency, and solve the problem of difficult positioning when three bundles of reinforcing bars are docked. The anti-slip texture or micro-protrusions on the inner side of the ring enhance the friction and further ensure the docking stability.

[0024] This structure eliminates the need for specialized grouting sleeves and grouting materials, avoiding the drawbacks of high grouting connection costs and long curing times, making it particularly suitable for cast-in-place concrete structures. The connection calibration structure is made of φ10 steel bars spot-welded together, which is easy to obtain and process, and can be retained at the connection point to participate in the stress, enhancing overall stability.

[0025] The overall structure comprehensively solves the problems of excessive joints, difficult calibration, high cost, and limited applicability in the connection of three-bar bundles by staggered joint design, simple calibration function and welding fixation method. It is easy to construct and the connection strength is reliable, which significantly improves the connection quality and efficiency of three-bar bundles in cast-in-place scenarios.

[0026] Other features and advantages of the present invention will become clear from the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings. Attached Figure Description

[0027] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the present invention and, together with their description, serve to explain the principles of the present invention.

[0028] Figure 1 This is a schematic diagram of the overall structure of a steel reinforcement connection with three bundles of parallel bars;

[0029] Figure 2 This is a schematic diagram of a three-ribbed bundle structure.

[0030] Figure 3This is a schematic diagram of the three-rib bundle structure.

[0031] Figure 4 This is a schematic diagram of the connection calibration structure;

[0032] Figure 5 This is a plan view of the connection calibration structure;

[0033] Figure 6 This is a schematic diagram of the connection between the lower three-rib bundle structure and the connection calibration structure;

[0034] Figure 7 This is a schematic diagram of a three-bar bundled steel reinforcement connection structure.

[0035] Figure 8 This is an example of a steel reinforcement connection structure with three bundles of parallel bars;

[0036] Figure 9 This is Example 2 of a steel reinforcement connection structure with three bundles of parallel bars;

[0037] Figure 10 This is Example 3 of a steel reinforcement connection structure with three bundles of parallel bars.

[0038] Figure label:

[0039] Lower three-rib bundle structure 10; Upper three-rib bundle structure 20; Weld point 11;

[0040] Connection calibration structure 30; ring 31; connecting rod 32;

[0041] The distance is offset by L. Detailed Implementation

[0042] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present invention.

[0043] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0044] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0045] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0046] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0047] In the specification and claims of this utility model, the terms "first" and "second" may explicitly or implicitly include one or more of those features. In the description of this utility model, unless otherwise stated, "multiple" means two or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0048] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and other terms indicating orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0049] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0050] The following describes in detail, with reference to the accompanying drawings, the steel bar connection structure of the three-bar bundle according to an embodiment of the present utility model.

[0051] A steel bar connection structure for three-bar bundles according to an embodiment of the present invention includes a lower three-bar bundle structure 10 and an upper three-bar bundle structure 20. Both the lower three-bar bundle structure 10 and the upper three-bar bundle structure 20 contain three steel bars, and at least one steel bar has a length that is different from the length of the other two steel bars. This length difference allows the splicing interface to be staggered to form a staggered distance L, so as to disperse the force, avoid stress concentration, and improve the overall connection strength. After the lower three-bar bundle structure 10 and the upper three-bar bundle structure 20 are connected, the three steel bars are spliced ​​to form an equal length state, and the two are fixed together by welding points to achieve a reliable connection of the three-bar bundle and transfer stress.

[0052] In other words, such as Figures 1 to 3 As shown, according to an embodiment of this utility model, a three-bar bundled steel reinforcement connection structure includes a lower three-bar bundled structure 10 and an upper three-bar bundled joint 20, which are fixed by welding points to form a complete three-bar bundled connection system. Both the lower three-bar bundled structure 10 and the upper three-bar bundled structure 20 consist of three longitudinal reinforcing bars arranged in a triangular pattern. The three bars are welded together and fixed by multiple welding points 11. To achieve staggered joint distribution, both structures employ a design where "at least one bar has a different length than the other two."

[0053] By employing a design where "at least one rebar is of a different length," the joints of the three-stranded rebar bundles are staggered longitudinally, avoiding stress concentration problems caused by concentrated joints in traditional welding. Under actual load, the load is distributed through multiple staggered joints, reducing the load on individual joints and significantly improving the overall crack resistance and load-bearing capacity of the connection. Furthermore, it eliminates the need for specialized grouting sleeves and grouting materials; the connection can be completed solely through the rebar's own length design and spot welding, saving the need for grouting curing. This is particularly suitable for the rapid construction requirements of "welding and pouring immediately" in cast-in-place concrete structures.

[0054] After the three reinforcing bars are joined, they form an equal length and are arranged in a triangular pattern to ensure that the effective cross-sectional area of ​​the bundle of three reinforcing bars remains unchanged, maintaining the original design mechanical properties (such as shear resistance and load-bearing capacity). The welding fixing method forms a rigid connection between the two sections of the structure, avoiding relative slippage and further ensuring the overall stress stability.

[0055] In some specific embodiments, both the lower three-bar bundle structure 10 and the upper three-bar bundle structure 20 have two bars of the same length and a third bar of different length.

[0056] In some specific embodiments, the lengths of the three reinforcing bars in the lower three-bar bundle structure 10 and the upper three-bar bundle structure 20 are different.

[0057] Specifically, such as Figures 8 to 10As shown, the length states of the lower three-bar bundled structure 10 and the upper three-bar bundled structure 20 correspond to each other, that is, they adopt the same length arrangement: when one section is "two bars of equal length and the third bar is staggered and of unequal length", the other section must also be "two bars of equal length and the third bar is staggered and of unequal length"; if one section is "all three bars are staggered and of unequal length", then the other section must also be "all three bars are staggered and of unequal length".

[0058] The purpose of this corresponding design is to ensure that the three reinforcing bars are of equal length after splicing by matching the length arrangement of the two structural segments, through complementary length differences. For example, when the length of two reinforcing bars in the lower three-bar bundle structure 10 is L1 and the length of the third bar is L1-L (L is the staggered distance), the length of the two corresponding reinforcing bars in the upper three-bar bundle structure 20 must be L2 and the length of the third bar must be L2+L, and satisfy L1+L2=(L1-L)+(L2+L), so that the total length of the three reinforcing bars after splicing is L1+L2, achieving equal length.

[0059] When the length of one rebar in the lower three-bar bundle structure 10 is L1, the length of the second rebar is L1+L, and the length of the third rebar is L1+2L (L is the staggered distance), the length of one rebar at the corresponding position in the upper three-bar bundle structure 20 must be L2, the length of the second rebar is L2-L, and the length of the third rebar is L2-2L, and satisfy L1+L2=(L1+L)+(L2-L)=(L1+2L)+(L2-2L), so that the total length of the three rebars after splicing is L1+L2, achieving equal length.

[0060] Its effects are reflected in the following aspects: On the one hand, it avoids the overlap of joints or the failure to meet the standard due to the mismatch of the two structural arrangement forms, ensuring compliance with the requirements of the "Code for Welding and Acceptance of Reinforcing Steel"; on the other hand, through the complementarity of the corresponding arrangement forms, it ensures the overall stress continuity of the three-bar bundle after splicing, and each steel bar can bear the load evenly, reducing local stress concentration, improving the stability and reliability of the connection structure, while simplifying the length adjustment process in construction and improving the construction efficiency in cast-in-place scenarios.

[0061] In some specific implementations, the offset distance L formed by the length difference between steel bars of different lengths is not less than 35 times the diameter of the steel bar and not less than 500 mm.

[0062] Specifically, the staggered distance L formed by the length difference between any two reinforcing bars must meet the following requirements: L is not less than 35 times the diameter of the reinforcing bar, and not less than 500 mm. For example, if the diameter of the reinforcing bar is 20 mm and 35 times the diameter is 700 mm, then the staggered distance L should be ≥700 mm to ensure that the joints are completely dispersed in the longitudinal direction and avoid overlap.

[0063] During construction, the lower three-bar bundle structure 10 is first processed and formed according to the design length. Then, the length of each bar in the upper three-bar bundle structure 20 is determined according to its length parameters to ensure that the total length is equal. The joints of the three bars are placed in different longitudinal positions, and finally, they are fixed together by spot welding to form a whole.

[0064] This design maximizes the dispersion of the joints of the three-bar bundles, effectively solving the problem of joint concentration in traditional welding. Combined with the equal length state after butt welding, it ensures the overall stress continuity of the bundled steel bars, meeting the dual requirements of connection strength and construction convenience in cast-in-place scenarios.

[0065] Preferably, to further reduce stress abrupt changes at the weld joint, an arc-shaped transition section or a gradually changing diameter section (not shown) is provided at the staggered rebar joint of the lower three-bar bundle structure 10 and the upper three-bar bundle structure 20. The arc-shaped transition section at the rebar joint is formed by cold working process, and the transition radius is 3-5 times the diameter of the rebar; the length of the gradually changing diameter section is 10-15 times the diameter of the rebar, linearly increasing from the joint end to both sides to 1.2 times the original diameter and then maintaining a constant diameter. This design makes the stress flow at the weld joint smoother, and combined with the staggered joint design, it further improves crack resistance, especially suitable for high stress load scenarios (such as bridge pile foundations). The setting of the arc-shaped transition section or the gradually changing diameter section solves the defect of the prior art that only disperses stress by staggering distribution but does not optimize the joint itself. By optimizing the material distribution, the stress concentration coefficient is greatly reduced, and combined with the spot welding fixing method, the fatigue life of the connection is significantly improved.

[0066] In some specific embodiments, a connection calibration structure 30 is also included, which is used to realize the docking calibration between the lower three-rib bundle structure 10 and the upper three-rib bundle structure 20.

[0067] The connection calibration structure provides a rigid positioning frame for the docking of the lower three-bar bundled structure and the upper three-bar bundled structure. It can effectively limit the horizontal displacement or torsion of the steel bars that may occur during the docking process, and ensure that the steel bar joints of the two structures are accurately aligned. This solves the problems of difficult calibration and low accuracy in traditional manual docking.

[0068] Preferably, the connecting calibration structure 30 consists of two rings 31 and three connecting rods 32 of equal length. The three connecting rods 32 are arranged in a ring at equal intervals and staggered according to the arrangement of the three-bar bundle. This can form radial constraints on the three steel bars in the lower three-bar bundle structure 10 and the upper three-bar bundle structure 20, so as to limit the steel bars from shifting during the docking process and realize the positioning and fixing of the three-bar bundle steel bars.

[0069] Specifically, such as Figures 4 to 6As shown, the connection calibration structure consists of two circular rings 31 and three connecting rods 32 of equal length, and is made of φ10 steel bars by spot welding.

[0070] The ring 31 is a closed ring structure. Its diameter is determined according to the outer diameter of the three-rib bundle. It needs to be slightly larger than the outer diameter of the three-rib bundle to ensure that it can be stably fitted outside the three-rib bundle, while providing sufficient radial constraint space.

[0071] Connecting rods 32, acting as connecting ribs, are arranged in a ring at equal intervals along the inner side of the circular ring (the included angle between two adjacent connecting rods 32 is 120°), and are staggered according to the triangular arrangement of the three parallel ribs. That is, the position of the connecting rods 32 corresponds to the gap between the three parallel ribs, avoiding interference with the rib body and ensuring that the bundle of three parallel ribs can smoothly pass through the calibration structure.

[0072] During construction, the connecting calibration structure 30 is first vertically inserted into the upper part of the lower three-bar bundle structure 10, so that the three steel bars of the lower three-bar bundle structure 10 are respectively embedded in the gap formed by the ring 31 and the connecting rod 32. At this time, the ring 31 and the connecting rod 32 form a radial limit on the lower three-bar bundle structure 10, preventing it from shifting in the horizontal direction. After adjustment, the connecting calibration structure 30 and the lower three-bar bundle structure 10 are fixed by spot welding to ensure that their relative positions are stable.

[0073] After the lower three-bar bundle structure 10 and the connecting calibration structure 30 are fixed, the lower end of the upper three-bar bundle structure 20 is vertically inserted into the upper end of the connecting calibration structure 30. Due to the limiting effect of the connecting calibration structure 30, the three steel bars of the upper three-bar bundle structure 20 will enter the corresponding gap along the guide of the connecting rod 32, thus naturally aligning with the corresponding steel bars of the lower three-bar bundle structure 10, ensuring precise fit at the joint position. After the upper and lower three-bar bundle structures are connected and welded, the connecting calibration structure 30 remains in the middle of the connection point and does not need to be removed, continuing to constrain the bundled steel bars.

[0074] The connecting calibration structure 30, through the combined design of the ring 31 and the connecting rod 32, provides a rigid positioning frame for the docking of the lower three-bar bundle structure 10 and the upper three-bar bundle structure 20. This effectively limits any horizontal offset or torsion that may occur during the docking process, ensuring precise alignment of the rebar joints in both structures. This solves the problems of difficult calibration and low accuracy in traditional manual docking. Traditional three-bar bundle docking requires multiple people to adjust the rebar positions, which is time-consuming and prone to deviations. The connecting calibration structure, however, can quickly guide the rebars into the correct position, reducing adjustment time and significantly improving docking efficiency. This is particularly suitable for cast-in-place concrete structures where construction progress is critical. During the docking process, the radial constraint of the connecting calibration structure 30 on the rebars prevents misalignment of the joints caused by external forces (such as construction vibration or the rebar's own weight), ensuring complete contact of the joint end faces during welding. This provides a foundation for subsequent welding quality. Furthermore, after welding, the retained calibration structure can further enhance the overall stiffness of the bundled rebars and improve the stability of the connection. Meanwhile, the connection and calibration structure is made of φ10 steel bars through spot welding. The material is readily available, the processing technology is simple, and it does not rely on complex equipment or special materials. Construction is convenient and highly compatible with the "rapid construction and immediate fixation" requirements of cast-in-place concrete structures, avoiding the dependence on curing time associated with grouting connections. Through this technical solution, the connection and calibration structure effectively solves the butt joint calibration problem when connecting three-bar bundles, providing an important guarantee for the reliability and construction efficiency of the overall connection structure.

[0075] Preferably, the inner side of the ring 31 is provided with anti-slip texture or micro-protrusions to enhance the friction with the steel bars in the lower three-bar bundle structure 10 and the upper three-bar bundle structure 20, and to prevent the steel bars from shifting relative to each other during the connection process.

[0076] Specifically, the circular ring 31 connecting the calibration structure 30 is formed by bending φ10 steel bars. The anti-slip texture or micro-protrusions on its inner side are made through a cold working process: the anti-slip texture can be a continuous strip pattern distributed along the inner circumference of the circular ring 31, with a depth of about 0.5-1mm and a spacing of 3-5mm; the micro-protrusions are uniformly distributed hemispherical protrusions with a diameter of 1-2mm, a height of 0.3-0.5mm, and a spacing of 5-8mm between adjacent protrusions. The two structural forms can be selected according to construction requirements. The core is to increase the contact friction between the inner side of the circular ring 31 and the surface of the steel bars in the bundle of three parallel bars.

[0077] During construction, when the lower three-bar bundle structure 10 is vertically inserted into the connection calibration structure 30, the outer surface of the rebar makes close contact with the anti-slip texture or micro-protrusions on the inner side of the ring 31. The texture or protrusions embed into the tiny unevenness of the rebar surface (or create mechanical interlocking), forming additional constraints. Similarly, when the upper three-bar bundle structure 20 is inserted, the relative sliding is further restricted through this contact method. This design does not affect the vertical insertion of the rebar, but it effectively prevents the rebar from shifting or rotating in the horizontal direction. Especially during the butt joint adjustment stage, it can reduce positional deviations caused by external force contact or vibration.

[0078] The anti-slip texture or micro-protrusions on the inner side of the ring enhance the radial constraint effect of the connection alignment structure on the three-bar bundle by increasing contact friction. The inner side of the traditional ring is a smooth surface, and the positioning between the steel bar and the ring mainly relies on the gap fit. Relative slippage can easily occur during construction vibration or eccentricity of the steel bar's own weight, leading to docking deviation. However, the anti-slip texture or micro-protrusions can ensure that the joint of the upper and lower three-bar bundle structure remains precisely aligned before welding and fixing through mechanical interlocking.

[0079] Meanwhile, this design requires no additional complex processing steps, achieving it solely through cold working without altering the overall stiffness and material properties of the connection calibration structure, and at a low cost. For common outdoor operations or multi-trade construction scenarios in cast-in-place concrete structures, this enhanced stability reduces the number of repeated adjustments, further shortening the connection time for a single joint and indirectly improving construction efficiency. Furthermore, the close contact between the anti-slip texture or micro-protrusions and the reinforcing steel reduces micro-vibrations during welding, providing a more stable operating base for spot welding, helping to reduce welding defect rates and ensure connection quality.

[0080] This utility model discloses a steel bar connection structure with three parallel bars bundled together. Through the coordinated cooperation of the lower three parallel bar bundled structure 10, the upper three parallel bar bundled structure 20, and the optional connection calibration structure 30, a highly efficient and reliable connection of the three parallel bars bundled together is achieved.

[0081] The lower three-bar bundle structure 10 and the upper three-bar bundle structure 20 adopt a design with at least one bar of different length, so that the splicing interface is staggered to form a staggered distance L, which disperses stress and avoids concentration, and solves the strength hazards caused by the dense welded joints in traditional welding. After the butt joint, it is fixed into a whole by spot welding to form a three-bar bundle of equal length, ensuring the effective transmission of force.

[0082] The connection calibration structure 30 consists of a ring 31 and a connecting rod 32, which can form a radial constraint on the reinforcing bars, limit the docking offset, improve calibration efficiency, and solve the problem of difficult positioning when the three-bar bundled reinforcing bars are docked; the anti-slip texture or micro-protrusions on the inner side of the ring 31 enhance the friction and further ensure the docking stability.

[0083] This structure eliminates the need for specialized grouting sleeves and grouting materials, avoiding the drawbacks of high grouting connection costs and long curing times, making it particularly suitable for cast-in-place concrete structures. The connection calibration structure 30 is made of φ10 steel bars spot-welded together, which is easy to source and process, and can be retained at the connection point to participate in the stress, enhancing overall stability.

[0084] The overall structure comprehensively solves the problems of excessive joints, difficult calibration, high cost, and limited applicability in the connection of three-bar bundles by staggered joint design, simple calibration function and welding fixation method. It is easy to construct and the connection strength is reliable, which significantly improves the connection quality and efficiency of three-bar bundles in cast-in-place scenarios.

[0085] Of course, for those skilled in the art, other structures and working principles of the three-bar bundled steel bar connection structure are understandable and achievable, and will not be described in detail in this utility model.

[0086] Although specific embodiments of the present invention have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A steel reinforcement connection structure with three bundles of parallel bars, characterized in that, It includes a lower three-bar bundle structure (10) and an upper three-bar bundle structure (20); both the lower three-bar bundle structure (10) and the upper three-bar bundle structure (20) contain three steel bars, and at least one steel bar has a length that is different from the length of the other two steel bars. This length difference allows the splicing interface to be staggered to form a staggered distance (L), so as to disperse the force and avoid stress concentration, thereby improving the overall connection strength; after the lower three-bar bundle structure (10) and the upper three-bar bundle structure (20) are connected, the three steel bars are spliced ​​to form an equal length state, and the two are fixed together by welding points to achieve a reliable connection of the three-bar bundle and transmit stress.

2. The steel reinforcement connection structure with three bundled bars according to claim 1, characterized in that, It also includes a connection calibration structure (30) for achieving docking calibration between the lower three-rib bundled structure (10) and the upper three-rib bundled structure (20).

3. The steel reinforcement connection structure with three bundled bars according to claim 1, characterized in that, In both the lower three-bar bundled structure (10) and the upper three-bar bundled structure (20), two bars have the same length and the third bar has a different length.

4. The steel reinforcement connection structure with three bundled bars according to claim 1, characterized in that, In the lower three-bar bundled structure (10) and the upper three-bar bundled structure (20), the lengths of the three reinforcing bars are different.

5. The steel reinforcement connection structure with three bundled bars according to claim 3 or 4, characterized in that, The staggered distance (L) formed by the length difference between steel bars of different lengths shall not be less than 35 times the diameter of the steel bar and not less than 500 mm.

6. The steel reinforcement connection structure with three bundled bars according to claim 2, characterized in that, The connection calibration structure (30) consists of two rings (31) and three connecting rods (32) of equal length. The three connecting rods (32) are arranged in a ring at equal intervals and staggered according to the arrangement of the three-bar bundle. This can form radial constraints on the three bars in the lower three-bar bundle structure (10) and the upper three-bar bundle structure (20) to limit the displacement of the bars during the docking process and realize the positioning and fixing of the three-bar bundle bars.

7. The steel reinforcement connection structure with three bundled bars according to claim 6, characterized in that, The inner side of the ring (31) is provided with anti-slip texture or micro-protrusions to enhance the friction with the steel bars in the lower three-bar bundle structure (10) and the upper three-bar bundle structure (20) and prevent the steel bars from shifting relative to each other during the docking process.

8. The steel reinforcement connection structure with three bundled bars according to claim 6, characterized in that, The connection calibration structure (30) is made of φ10 steel bars by spot welding.

9. The steel reinforcement connection structure with three bundled bars according to claim 2, characterized in that, The connecting calibration structure (30) is vertically inserted into the lower three-bar bundle structure (10) and then welded and fixed. The upper three-bar bundle structure (20) is vertically inserted into the connecting calibration structure (30) and then fully fits with all the steel bar joints of the lower three-bar bundle structure (10). It is then fixed by welding. After welding, the connecting calibration structure (30) is retained in the middle position.

10. The steel reinforcement connection structure with three bundled bars according to claim 1, characterized in that, The connection between the lower three-rib bundle structure (10) and the upper three-rib bundle structure (20) is fixed by spot welding.

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