I-shaped column-full dry type connection RC beam column joint and connection method

Abstract

The invention discloses an I-shaped column-full dry type connection RC beam column joint and a connection method, and belongs to the technical field of building structure engineering. The joint comprises a prefabricated I-shaped column, a stepped beam, a shear connector and a U-shaped connecting steel plate. A long bracket and a short bracket are respectively arranged at the top and the bottom of the I-shaped column; the end part of the step-shaped beam is in an inverted step shape and is provided with an extending section; the shear connector is a long-strip-shaped steel member provided with a screw rod; and the U-shaped steel plate is provided with screw holes which are respectively matched with the shear connector and the beam end screw. During connection, rapid assembly is achieved in the mode that the brackets of the upper column and the lower column are in lap joint, shear key grooves are interlocked, the shear connectors penetrate into the square holes, the beam bodies are supported on the combined brackets, and finally the U-shaped steel plates are used for anchoring. According to the joint, complete dry type operation is achieved, cast-in-place concrete and steel bar welding are not needed, the construction efficiency is remarkably improved, wet operation is reduced, loads can be borne after installation, the overall performance is reliable, and the development requirement of fabricated buildings is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building structure engineering, in particular to a beam-column joint connection technology of a fabricated concrete structure, and especially to a H-shaped column-full dry connection RC beam-column joint and a connection method. BACKGROUND

[0002] Fabricated buildings have become an important direction for the transformation and upgrading of the construction industry due to their advantages of energy saving and emission reduction, fast construction, and quality controllability. The overall performance of fabricated structures, especially their seismic performance and safety, largely depends on the reliability and construction quality of the joint connection.

[0003] At present, common fabricated concrete beam-column joints mostly adopt the design concept of "equivalent cast-in-place", mainly including grouting sleeve connection and post-cast integral connection technologies. Although these methods can ensure the integrity of the structure to some extent, there are still many limitations in actual engineering applications: first, the end of the prefabricated component needs to extend a large number of steel bars during factory production, which are prone to deformation or damage during transportation and hoisting, increasing the difficulty and cost of protection. Second, during the on-site installation stage, the steel bars in the joint area are densely distributed and come from various sources, and steel bars of different directions are prone to spatial position conflicts, requiring high hoisting sequence and construction precision of the component, which often leads to low construction efficiency and increased labor costs. In addition, post-cast concrete requires a certain curing time, prolonging the construction period, and the amount of on-site wet work is large, which is contrary to the environmental protection and efficiency of the building industrialization.

[0004] Therefore, it is of great significance to develop a full dry beam-column joint connection technology that is convenient to install, reliable in force, and does not require on-site wet work, for promoting the further development of fabricated buildings. SUMMARY

[0005] The purpose of the present application is to overcome the shortcomings of the prior art, provide a H-shaped column-full dry connection RC beam-column joint and a connection method, to solve the problems of complex steel bar alignment, multiple on-site wet work, and low construction efficiency of existing fabricated joints, and realize rapid, efficient, and reliable assembly of the joint.

[0006] To achieve the above-mentioned purpose, the following technical solutions are adopted in the present application: A H-shaped column-full dry connection RC beam-column joint, comprising a H-shaped column, a stepped beam, a shear connector, and a U-shaped connecting steel plate; The H-shaped column is prefabricated from concrete, and a long corbel is provided at the top and a short corbel is provided at the bottom, and the length of the long corbel is greater than that of the short corbel; The end of the stepped beam is in the shape of an inverted ladder, and a protruding section is provided, and the length of the protruding section is equal to the length difference between the long corbel and the short corbel; The anti-shear connector is a long strip-shaped steel member, and threaded rods are arranged at the upper and lower ends of the long strip-shaped steel member; The U-shaped connecting steel plate is provided with a first group of screw holes matched with the threaded rods of the anti-shear connector at one part, and a second group of screw holes with the same number at another part.

[0007] Further, a plurality of square large holes are arranged on the short bracket, and square small holes corresponding to the square large holes in number and position are arranged on the long bracket.

[0008] Further, threaded rods are pre-buried at the two ends of the stepped beam, and the specifications and number of the threaded rods correspond to the threaded rods on the anti-shear connector.

[0009] Further, the anti-shear connector comprises a first square solid body at the upper part and a second square solid body at the lower part, which are matched with the square large hole and the square small hole, respectively.

[0010] Further, the U-shaped connecting steel plate is composed of a bottom plate, side plates extending downward from both sides of the bottom plate, and a top plate extending upward from one end of the bottom plate close to the node core area.

[0011] Further, a prismatic shear key is arranged at the top end section of the I-shaped column, and a prismatic shear groove matched in shape is arranged at the bottom end section.

[0012] The application also provides a connecting method of the node, comprising the following steps: S1, prefabricating the I-shaped column, the stepped beam, the anti-shear connector and the U-shaped connecting steel plate in a factory; S2, overlapping the short bracket at the bottom of the upper I-shaped column on the long bracket at the top of the lower I-shaped column, and embedding the shear key at the bottom end of the upper column into the shear groove at the top end of the lower column; S3, sequentially inserting the anti-shear connector into the square large hole of the short bracket and the square small hole of the long bracket; S4, hoisting the stepped beam, so that the end extending section of the stepped beam is overlapped on the combined support surface composed of the long and short brackets; S5, sleeving the U-shaped connecting steel plate on the upper end threaded rod of the anti-shear connector and the pre-buried threaded rod of the beam end, and fastening with a nut.

[0013] Compared with the prior art, the application has the following beneficial effects: 1. Dry connection, efficient construction: all components are prefabricated in a factory, and only overlapping, inserting and bolt connection are needed on site, which completely avoids steel binding, welding and concrete cast-in-place operation, and the construction speed is extremely fast, and the construction period is significantly shortened.

[0014] .2. Clear force, reliable performance: shear force is transmitted through shear connectors, U-shaped steel plates provide restraint and transmit bending moment, shear key slots bear vertical shear force, multiple lines of defense work together, node bearing capacity and seismic performance are good, and the design goal of "equivalent cast-in-place" can be achieved.

[0015] 3. Controllable quality, environmental protection and energy saving: component precision is guaranteed by the factory, human factors are small on site, and quality is stable. Construction waste and on-site wet work are greatly reduced, meeting the requirements of green construction and energy saving and emission reduction.

[0016] 4. Easy to install, good fault tolerance: corbels provide natural support, shear connectors and square holes are gap-fitted, installation guidance is good, adaptability to construction errors is stronger, and requirements for worker technical level are reduced. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 A schematic diagram of the structure of the I-shaped column in the I-shaped column-full dry connection RC beam-column joint in the embodiment; Figure 2 A schematic diagram of the assembly process of the corbel combination in the I-shaped column-full dry connection RC beam-column joint in the embodiment; Figure 3 A schematic diagram of the structure of the I-shaped column combination in the I-shaped column-full dry connection RC beam-column joint in the embodiment; Figure 4 A schematic diagram of the structure of the I-shaped column-full dry connection RC beam-column joint in the embodiment; Figure 5 An exploded view of the I-shaped column-full dry connection RC beam-column joint in the embodiment; Figure 6 A schematic diagram of the frame structure of the I-shaped column-full dry connection RC beam-column joint in the embodiment; In the figure: 1-I-shaped column; 11-long corbel; 12-short corbel; 13-shear key; 14-shear slot; 111-square small hole; 121-square large hole; 2-stair-type beam; 21-protruding section; 22-pre-buried screw rod; 3-shear connector; 31-first square solid; 32-second square solid; 33-screw rod; 4-U-shaped connection steel plate; 41-bottom plate; 42-side plate; 43-top plate; 44-first group of screw holes; 45-second group of screw holes. DETAILED DESCRIPTION

[0018] The application will be further described in detail below in combination with the drawings and specific embodiments, but the protection scope of the application is not limited thereto. EMBODIMENT

[0019] As Figures 1 to 6 shown, the embodiment provides a specific implementation of an I-shaped column-full dry connection RC beam-column joint.

[0020] The I-shaped column (1) is prefabricated in a factory with C40 concrete, and its cross section is a standard I shape with a profile size of 600mm × 600mm and a column height of 3000mm. The top of the column is integrally formed with a cuboid long bracket (11) with a cross section size of 300mm × 300mm and a length of 500mm. The bottom of the column is integrally formed with a cuboid short bracket (12) with a cross section size of 300mm × 300mm and a length of 400mm. Four square small holes (111) with a side length of 40mm are reserved on the long bracket (11), and the hole centers are spaced 100mm along the beam length and 150mm along the beam width. Four square large holes (121) with a side length of 60mm are reserved on the short bracket (12) corresponding to the square small holes (111). A prismatic concrete shear key (13) is provided at the center of the top surface of the column, with an upper surface size of 300mm × 300mm, a lower surface size of 400mm × 400mm, and a height of 150mm. A prismatic shear groove (14) with a matching shape is provided at the center of the bottom surface of the column. The contact surface of the bracket and the surrounding area of the shear key groove are roughened, and the stirrup configuration rate is increased to enhance the shear capacity.

[0021] The stepped beam (2) is prefabricated with C40 concrete, and the beam end is processed into an inverted stepped shape to form an overhanging segment (21) with a height of 300mm and a length of 100mm (i.e. 500mm-400mm). Inside the beam end, four M20 grade, 20mm diameter, full-threaded screw rods (22) are embedded, with an exposed length of 40mm.

[0022] The shear connector (3) is made of Q355B steel by integral forging or machining, with a total length of 600mm. The upper part is a first square solid (31) with a cross section size of 59mm × 59mm, designed to form a 1mm gap fit with the square large hole (121) (60mm) on the short bracket. The lower part is a second square solid (32) with a cross section size of 39mm × 39mm, designed to form a 1mm gap fit with the square small hole (111) (40mm) on the long bracket. Two 20mm diameter, externally threaded screw rods (33) are provided at the upper and lower ends of the connector, with a length of about 40mm. To enhance the compactness, structural adhesive can be applied to the surface of the shear connector (3) to fill the gap between it and the hole wall. The size difference between the upper and lower square solids can effectively prevent the connector from falling out of the hole, facilitating construction and installation.

[0023] The U-shaped connecting steel plate (4) is made of Q355B steel plate with a thickness of 12 mm. The main body is a rectangular bottom plate (41). One end of the bottom plate (41) (close to the node core area) is bent upward by 90 degrees to form a top plate (43) with a length of about 100 mm, which is used to tightly attach the column body of the I-shaped column (1). The two sides of the bottom plate (41) are bent downward by 90 degrees to form two side plates (42) with a length of about 20 mm. Two groups of a total of 8 screw holes are formed on the bottom plate (41): 4 of them are the first group of screw holes (44), the hole diameter and hole pitch of which match the screw rod (33) on the shear connector (3); the other 4 are the second group of screw holes (45), the hole diameter and hole pitch of which match the pre-buried screw rod (22) at the end of the stepped beam (2).

[0024] The field installation of the node is carried out according to the following steps: S1, all components (I-shaped column 1, stepped beam 2, shear connector 3, U-shaped connecting steel plate 4 and matching nuts) are prefabricated in the factory, and are transported to the construction site after passing the inspection.

[0025] S2, hoist the lower I-shaped column (1) and fix it in place. Then hoist the upper I-shaped column (1) and accurately overlap the short bracket (12) at the bottom of the upper column with the long bracket (11) at the top of the lower column. During this process, the operator needs to guide the shear key (13) of the upper column to accurately embed into the shear slot (14) of the lower column to realize vertical bearing and preliminary shear resistance.

[0026] S3, from the side of the node, the shear connector (3) is vertically and sequentially inserted into the square large hole (121) of the short bracket (12) and the square small hole (111) of the long bracket (11). Due to the gap design between them, the insertion process is smooth, and after being positioned, the connector is reliably positioned, connecting the upper and lower brackets into a whole to work together.

[0027] S4, hoist the prefabricated stepped beam (2) and smoothly overlap the protruding section (21) at the end of the beam on the horizontal support surface formed by the top surface of the upper column short bracket (12) and the lower column long bracket (11).

[0028] S5, lift the U-shaped connecting steel plate (4) so that the first group of screw holes (44) are aligned with the screw rod (33) at the upper end of the shear connector (3), and the second group of screw holes (45) are aligned with the pre-buried screw rod (22) at the end of the stepped beam (2). After all the screw rods are inserted, high-strength nuts are tightened on the screw rods and a designed pre-tightening force is applied, so that the beam, column and shear connector are firmly anchored together to form a complete rigid node connection.

[0029] The embodiment successfully realizes the full dry type and non-welding node connection through the cooperation of the specific size and material. Field installation is simple and efficient, and does not need any concrete cast-in-place operation and steel bar connection operation. The construction period is shortened by more than 50% compared with the traditional mode. The combination design of the shear key / slot and the shear connector effectively transmits the vertical shear and the bending moment. The U-shaped steel plate not only provides reliable connection, but also restrains the beam-column connection end, and optimizes the stress distribution. Through finite element analysis, the node can immediately bear the design load after installation, the bearing capacity, stiffness and energy dissipation capacity are equivalent to the cast-in-place node, and the requirements of the prefabricated building rapid construction, energy saving and carbon reduction and structural safety are fully met.

[0030] The above merely describes the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can make equivalent replacements or changes according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A full dry connection of H-shaped column-RC beam column joint, comprising an H-shaped column, a stepped beam, a shear connector and a U-shaped connecting steel plate, characterized in that: the H-shaped column is prefabricated by concrete, and has a long bracket at the top and a short bracket at the bottom, the length of the long bracket is greater than that of the short bracket; the end of the stepped beam is configured as an inverted stepped shape and has an overhanging section, the length of the overhanging section is equal to the length difference between the long bracket and the short bracket; the shear connector is a long strip-shaped steel member, and both upper and lower ends of the shear connector are provided with threaded bolts; a part of the U-shaped connecting steel plate is provided with a first group of screw holes matched with the threaded bolts on the shear connector, and another part is provided with a second group of screw holes with the same number; 2. The I-shaped column-to-full dry connection RC beam column joint according to claim 1, wherein: at least four square large holes are provided on the short bracket, and square small holes corresponding in number and position to the square large holes are provided on the long bracket; the shear connector is configured to be simultaneously arranged in the square large holes and the square small holes.

3. The I-shaped column-to-full dry connection RC beam column joint according to claim 2, wherein: a threaded bolt is embedded in the end of the stepped beam, and the position of the threaded bolt corresponds to the second group of screw holes on the U-shaped connecting steel plate.

4. The I-shaped column-to-full dry connection RC beam column joint according to claim 3, wherein: the shear connector comprises a first square solid at the upper part and a second square solid at the lower part, the outer dimensions of the first square solid are matched with the square large holes with a gap, and the outer dimensions of the second square solid are matched with the square small holes with a gap.

5. The I-shaped column-to-full-pedestal connection RC beam-column joint according to claim 1, wherein: the U-shaped connecting steel plate comprises a rectangular bottom plate, side plates extending vertically from both sides of the bottom plate in the same direction, and a top plate extending vertically from one end of the bottom plate close to the joint core area.

6. The I-shaped column-to-full-pedestal connection RC beam-column joint according to claim 1, wherein: the top end cross section of the H-shaped column is provided with a prismatic shear key, and the bottom end cross section is provided with a prismatic shear groove matched with the shape of the shear key.

7. A method of connecting a full dry connection of an I-shaped column-RC beam column joint according to any one of claims 1 to 6, characterized in that, comprising the following steps: S1, prefabricating the H-shaped column, the stepped beam, the shear connector and the U-shaped connecting steel plate; S2, overlapping the short bracket at the bottom of the upper H-shaped column on the long bracket at the top of the lower H-shaped column, and embedding the shear key at the bottom end of the upper column into the shear groove at the top end of the lower column; S3, arranging the shear connector in the square large holes of the short bracket and the square small holes of the long bracket; S4, hoisting the stepped beam so that the overhanging section at the end of the stepped beam is overlapped on the support surface formed by the upper and lower brackets; S5, aligning the first group of screw holes of the U-shaped connecting steel plate with the threaded bolts at the upper end of the shear connector, and the second group of screw holes with the threaded bolts embedded in the end of the stepped beam, and installing nuts and fastening.

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