An optimized construction method for large-section beam-column joints

Abstract

This application relates to the field of building structure design and civil construction technology, and specifically discloses an optimized construction method for large cross-section beam-column joints, which includes the following steps: (1) Determining the arrangement of beam reinforcement: Based on the prestressed ducts, determine the position and distribution of the supporting stirrups, longitudinal reinforcement and stirrups; (2) Establishing the model of the steel column and prestressed beam-column joint: Use BIM to establish the model of the steel column and prestressed beam joint, find the positional relationship between the beam reinforcement, prestressed corrugated pipe and the steel column through model comparison, determine the connection relationship between each beam reinforcement and the steel column from the web passing through, the outer side bypassing, and the flange connection, and form a staggered relationship between the longitudinal and transverse prestressed beam reinforcements; According to the determined connection relationship between the beam reinforcement, prestressed corrugated pipe and the steel column, determine the position of the reserved holes on the web of the steel column and the connection parts on the flange of the steel column. This scheme uses BIM information model to deepen the beam-column joint to guide the steel structure processing and on-site installation.

Description

Technical Field

[0001] This invention relates to the field of building structure design and civil construction technology, specifically to an optimized construction method for large-section beam-column joints. Background Technology

[0002] With economic development, the application of long-span, long-cantilever structures in construction is increasing. These structures inevitably lead to increased column and beam cross-sectional dimensions. In most cases, we need to install steel sections in concrete structural columns and prestressed tendons in structural beams to meet load-bearing requirements. While prestressed tendons generally participate in load-bearing, the load-bearing capacity of a beam primarily relies on the reinforcing bars or steel sections. Prestressed tendons mainly address beam deflection and cracking issues. During construction, we have found that due to the large number and diameter of reinforcing bars at beam-column joints, and the presence of multiple rows of reinforcing bars in both longitudinal and transverse beams, the dense reinforcing bars and large-diameter corrugated metal pipes at beam-column joints are difficult to pass through the web of the steel column. This also easily causes conflicts between the prestressed corrugated pipes, reinforcing bars, and steel sections.

[0003] For example, the following problems exist in the arrangement and construction of reinforcing bars, structural steel, and prestressed corrugated pipes at large-section beam-column joints in an existing project:

[0004] (1) Due to the beam cross-section size of 2200*2400mm and the column cross-section size of 2400*2400mm, and the reinforcement is very dense, the reinforcement arrangement is very difficult.

[0005] (2) The prestressed corrugated pipe cannot pass smoothly through the web of the steel column.

[0006] (3) The longitudinal reinforcement of the prestressed beams in the longitudinal and transverse directions conflict at the beam-column joint, and cannot pass smoothly through the web of the steel column, nor can it be smoothly connected with the connecting plate and rebar connector on the steel column.

[0007] The aforementioned issues primarily highlight key and challenging aspects of construction, such as the positioning of prestressed corrugated pipes and longitudinal reinforcement bars in the steel columns, and the location of the connection between the longitudinal reinforcement bars and the steel columns. Conflicts between the pre-reserved positions of the beam reinforcement bars and the steel columns prevent the installation of the beam reinforcement bars, affecting the construction quality of the beam-column joint and increasing unnecessary rework later. Summary of the Invention

[0008] The purpose of this invention is to provide an optimized construction method for large-section beam-column joints, to clarify the positions of pre-reserved holes, connecting plates, and rebar connectors on steel columns, to complete the construction drawings through detailed design, and finally to guide the steel structure processing and on-site installation.

[0009] The optimized construction method for large-section beam-column joints includes the following steps:

[0010] (1) Determine the arrangement of beam reinforcement: Based on the prestressed duct, determine the position and distribution of the supporting stirrups, longitudinal bars and stirrups to ensure that the prestressed corrugated pipe can pass smoothly in the beam;

[0011] (2) Establishment of joint models for steel columns and prestressed beams and columns:

[0012] (2-1) Determine the connection relationship: Use BIM to build the node model of steel column and prestressed beam. Find the positional relationship between the beam reinforcement, prestressed corrugated pipe and steel column by comparing the model. Determine the connection relationship between each beam reinforcement and steel column from the three connection relationships of web passing through, outside bypassing and flange connection.

[0013] (2-2) For longitudinal and transverse prestressed beams, the reinforcement bars form a staggered layer relationship between upper and lower layers;

[0014] (2-3) For parallel multi-row beam reinforcement with flange connection, one row is welded to the steel column flange with a connecting plate, and the other rows are mechanically connected to the steel column flange with a rebar connector;

[0015] (2-4) Based on the determined connection relationship between the beam reinforcement, prestressed corrugated pipe and steel column, determine the position of the reserved holes on the web of the steel column and the connecting plate and connector on the flange of the steel column.

[0016] The beneficial effects of this plan are as follows:

[0017] (1) The beam-column joint is refined using BIM information model. The location of reserved holes, connecting plates and rebar connectors on the steel column is clarified through the model. Then, the construction drawings are drawn after the design is refined, and finally the steel structure processing and on-site installation are guided.

[0018] (2) By modeling and sorting out the possible beam reinforcement interference problems during node connection and installation, and planning connection schemes in advance for beam reinforcement interference, clarifying the connection points and connection methods at the nodes, reducing the impact on the construction quality of beam-column nodes caused by the conflict between the beam reinforcement and the reserved position on the steel column, and increasing unnecessary rework.

[0019] (3) The arrangement of beam reinforcement is based on prestressed ducts to ensure that prestressed corrugated pipes can pass smoothly through the beam, and to minimize the adjustment of the prestressed corrugated pipe routing during later construction, thereby reducing the difficulty of construction.

[0020] (4) Since the welding quality of connecting plates to steel columns is difficult to control, this scheme adopts one row of beam reinforcement to be connected to the steel column flange by welding connecting plates, and the other rows are mechanically connected to the steel column flange by steel bar connectors.

[0021] Preferred Option 1: As a further optimization of the basic scheme, in step (2-2), the beam reinforcement bars in different directions should be staggered by at least one steel bar diameter. This avoids beam reinforcement bars in different directions intersecting at the same elevation, which would increase the difficulty of arranging the beam reinforcement bars on site.

[0022] Preferred Option 2: As a further optimization of Preferred Option 1, in steps (2-3), the elevations of the connecting plates or rebar splices connecting the staggered beam reinforcement in different directions are at least one rebar diameter apart. This avoids beam reinforcement in different directions intersecting at the same elevation, increasing the difficulty of arranging the beam reinforcement on site.

[0023] Preferred Option 3: As a further optimization of Preferred Option 2, the connecting plates and rebar connectors in steps (2-3) that connect the beam reinforcement in the same direction and at the same level and are located on opposite sides of the flange are set at the same elevation. This avoids misalignment of the beam reinforcement, which could lead to intersections with beam reinforcement in different directions.

[0024] Preferred Option 4: As a further optimization of Preferred Option 3, the steel column in step (2) is welded from one I-beam and two T-beams. The webs of the two T-beams are welded to both sides of the web of the I-beam to form a steel column with a cross-section in the shape of a grid. This structural steel column is stable and centrally symmetrical. When it forms an intersection with the prestressed beams in the transverse and longitudinal directions, the beam reinforcements on each side are connected in the same way and structurally, which facilitates the arrangement of the beam reinforcements.

[0025] Preferred Option 5: As a further optimization of Preferred Option 4, in step (2-1), for the prestressed corrugated pipe that is directly opposite and perpendicular to the flange of the steel column at the node between the prestressed beam and the steel column, the prestressed corrugated pipe at this location is selected to pass through the web between two adjacent flanges of the steel column. This avoids the corrugated pipe going around the outside without damaging the steel column flange, which would result in a large bending amplitude in the corrugated pipe, thus hindering the later passage of prestressing tendons.

[0026] Preferred Option Six: As a further optimization of Preferred Option Four, it also includes step (3) prefabrication of steel columns. The welding of steel columns, the pre-drilled holes in steel columns, and the welding of connecting plates and connectors on the flanges of steel columns are completed in the factory. The construction of the joints between steel columns and each prestressed beam mainly revolves around the steel columns. Prefabrication of steel columns in the factory can make the pre-drilled holes and other connecting parts more accurate, which can reduce the difficulty of on-site reinforcement and installation.

[0027] Preferred Option Seven: As a further optimization of the basic option, a flange is provided on the side of the connecting plate opposite to the side welded to the flange of the steel column. The flange faces the side of the connecting plate that is welded to the beam reinforcement, and a through hole is provided on the flange for a single beam reinforcement to pass through. By providing a flange on the connecting plate and pre-opening a through hole on the flange, when the beam reinforcement is welded to the connecting plate, the beam reinforcement first passes through the through hole and then is welded to the connecting plate. Thus, the through hole has a positioning function for the beam reinforcement, facilitating the welding of the beam reinforcement, and at the same time reducing the positional error when arranging the beam reinforcement. Attached Figure Description

[0028] Figure 1 This is a diagram showing the distribution of reinforcement bars within a prestressed beam.

[0029] Figure 2 A comparison of the distribution of internal reinforcement bars in prestressed longitudinal beams and steel columns;

[0030] Figure 3 A comparison of the distribution of internal reinforcement bars in prestressed beams and steel columns;

[0031] Figure 4 A three-dimensional model of steel columns and prestressed beam-column joints;

[0032] Figure 5 A schematic diagram showing the fabrication and connection of pre-drilled holes, connecting plates, and rebar connectors on steel columns;

[0033] Figure 6 This is a cross-sectional view of a steel column;

[0034] Figure 7 This is a schematic diagram of the connection between the connecting plate and the steel column in Example 2;

[0035] Figure 8 for Figure 7 Enlarged view of section A;

[0036] Figure 9 for Figure 7 Enlarged view of section B. Detailed Implementation

[0037] The following detailed description illustrates the specific implementation method:

[0038] The reference numerals in the accompanying drawings include: connecting plate 10, limiting wheel 20, limiting post 21, mounting plate 22, and compression spring 23.

[0039] Example 1:

[0040] The optimized construction method for large-section beam-column joints includes the following steps:

[0041] (1)Determine the arrangement of beam reinforcement: Based on the prestressed ducts, determine the positions and distributions of supporting stirrups, longitudinal reinforcement, and stirrups to ensure that the prestressed corrugated pipes can pass smoothly within the beam.

[0042] (2)Establish the models of steel columns and prestressed beam-column joints:

[0043] (2-1)Determine the connection relationships: Use BIM to establish the models of steel columns and prestressed beam joints;

[0044] (a)First, determine the structure of the steel column. In this embodiment, the steel column is welded by one I-beam and two T-shaped steels. The webs of the two T-shaped steels are respectively welded on both sides of the web of the I-beam to form a steel section with a cross-section of a Chinese character "tian". And a reinforcing plate perpendicular to the web is welded between the I-beam and the T-shaped steel to enhance the strength and stability of the steel column;

[0045] (b)Find the positional relationships between the beam reinforcement, prestressed corrugated pipes and the steel column through model comparison, and determine the connection relationship between each beam reinforcement and the steel column from three connection relationships: passing through the web, bypassing outside, and connecting with the flange; for the prestressed corrugated pipe that is directly opposite and perpendicular to the flange of the steel column at the joint of the prestressed beam and the steel column, the prestressed corrugated pipe at this place is selected to pass through the web between two adjacent flanges of the steel column;

[0046] (2-2)For the beam reinforcement in the longitudinal and transverse prestressed beams to form a staggered relationship between the upper and lower layers, the beam reinforcement staggered in different directions (i.e., transverse and longitudinal) is at least staggered by one steel bar diameter;

[0047] (2-3)For multiple rows of parallel beam reinforcement connected by flanges, one row is welded to the flange of the steel column with a connecting plate, and the other rows are mechanically connected to the flange of the steel column with a steel bar coupler. The elevations of the connecting plates or steel bar couplers connecting the beam reinforcement staggered in different directions (i.e., transverse and longitudinal) are at least staggered by one steel bar diameter; <�

[0048] (2-4)According to the determined connection relationships between the beam reinforcement, prestressed corrugated pipes and the steel column, determine the reserved holes on the web of the steel column and the positions of the connecting plates and couplers on the flange of the steel column;

[0049] (2-5)Form the models of steel columns and prestressed beam-column joints.

[0050] (3)Pre-process the steel column: The welding of the steel column, the reserved holes of the steel column, and the welding of the connecting plates and couplers on the flange of the steel column are completed in the factory.

[0051] (4)Construct the beam-column joints: Based on the models of steel columns and prestressed beam-column joints formed in step (2), complete the docking construction of the prestressed beam and the steel column.

[0052] In step (1), taking the routing of the prestressed corrugated pipe as the main consideration, the positions of the supporting stirrups, longitudinal bars, and stirrups constituting the prestressed beam are optimized to form a structure as follows: Figure 1 The diagram shows the distribution of reinforcement bars within the prestressed beam.

[0053] In step (2), the distribution diagrams of the beam reinforcement of the transverse and longitudinal prestressed beams obtained in step (1) are used as the basis. By comparing the distribution diagrams of the beam reinforcement of the prestressed beams with the steel column structure, the relationship between the beam reinforcement and the steel column is analyzed. The relationship is mainly reflected in the following two aspects:

[0054] (1) The beam reinforcement is located within the steel column. This situation can be further divided into two scenarios. Scenario 1: The beam reinforcement or prestressed corrugated pipe is directly opposite and perpendicular to the flange of the steel column; Scenario 2: As shown in the attached... Figure 6 As shown, viewed from one side of the steel column, the middle of the steel column has a wing plate facing forward, while there are two wing plates on each side facing to the sides. There is a gap between the front wing plate and the two side wing plates, and the web plate is located behind the gap.

[0055] For scenario 1, where the beam reinforcement faces the front flange, the beam reinforcement and flange are connected by a flange connection, i.e., the beam reinforcement is interrupted here and its end is connected to the flange through a connecting plate or a rebar connector; however, for the case where the prestressed corrugated pipe faces the front flange, since the prestressed corrugated pipe cannot be interrupted, the prestressed corrugated pipe is bent outward into the gap between the front flange and the side flange and passes through the web.

[0056] In this embodiment, the longitudinal reinforcement of the prestressed beam is distributed in the upper and lower parts of the beam, with two layers of longitudinal reinforcement in each part. For longitudinal reinforcement using flange connection, the upper layer of longitudinal reinforcement in the upper part is connected to the flange through a connecting plate, and the lower layer of longitudinal reinforcement in the upper part is connected to the flange through a steel bar connector; the upper layer of longitudinal reinforcement in the lower part is connected to the flange through a steel bar connector, and the lower layer of longitudinal reinforcement in the lower part is connected to the flange through a connecting plate.

[0057] For scenario 2, a pre-drilled hole is made in the web behind the gap between the front wing and the side wing, as shown in the attached diagram. Figure 5 As shown, without interrupting the beam reinforcement, the method of passing through the web is selected, and the beam reinforcement or prestressed corrugated pipe is directly passed through the reserved hole.

[0058] (2) The beam reinforcement is outside the range of the steel column. In this case, the reinforcement is directly selected to bypass the outside and there is no connection with the steel column.

[0059] At the intersection of steel columns and prestressed beams, there is a three-way intersection: the transverse prestressed beam, the longitudinal prestressed beam, and the steel column. Besides resolving the connection between the prestressed beam and the steel column, the crossing of the reinforcement bars in the transverse and longitudinal prestressed beams must also be addressed. The reinforcement bars in the longitudinal and transverse prestressed beams are staggered between upper and lower layers to avoid crossing, as shown in the attached diagram. Figure 1-3 As shown, the prestressed beam has two layers of reinforcement in the upper part, namely the upper layer and the lower layer; when dealing with the intersection of longitudinal and transverse prestressed beam reinforcement, the transverse and longitudinal reinforcement are staggered, as shown in the attached figure. Figure 4 As shown, the transverse upper beam reinforcement overlaps the longitudinal upper beam reinforcement, the longitudinal upper beam reinforcement overlaps the transverse lower beam reinforcement, and the longitudinal lower beam reinforcement is at the bottom layer.

[0060] Example 2:

[0061] The difference between Example 2 and Example 1 is that in Example 2, as... Figure 7 As shown, a flange is machined on one side of the connecting plate 10. When the connecting plate 10 is welded to the flange, the side of the connecting plate 10 opposite to the flange is welded to the flange, thus making the flange parallel to the flange. Secondly, a through hole is machined on the flange for a single beam reinforcement to pass through, which can be used to position the beam reinforcement. When welding the beam reinforcement to the connecting plate 10, the beam reinforcement to be welded to the positioning plate is first passed through the through hole. Due to the positioning effect of the through hole, it is not necessary to confirm the position of the beam reinforcement on the connecting plate 10.

[0062] like Figure 8 , Figure 9 As shown, a slot leading to the center of the through hole is provided on the outer edge of the flange. A limiting wheel 20 is provided in the slot, and the limiting wheel 20 is rotatably connected to the side wall of the slot via a pin. One side of the limiting wheel 20 is provided with a ratchet, and a limiting structure is provided on the outer side of the flange. The limiting structure is located on the side where the ratchet is located. The limiting structure includes a mounting plate 22 welded to the flange. The middle of the mounting plate 22 is raised to form a mounting groove. A limiting post 21 is installed in the mounting groove, and a compression spring 23 is installed in the mounting groove to press the limiting post 21 against the ratchet. Through the cooperation of the limiting post 21 and the ratchet, the limiting wheel 20 can only rotate in one direction.

[0063] The outer circumferential surface of the limiting wheel 20 is provided with crisscrossing anti-slip patterns. When the beam reinforcement is inserted into the through hole, the friction between the beam reinforcement and the anti-slip patterns of the limiting wheel 20 causes the limiting wheel 20 to rotate in one direction, thereby pressing the limiting wheel 20 into the through hole. Since the limiting wheel 20 can only rotate in one direction, the friction between the anti-slip patterns and the beam reinforcement prevents the beam reinforcement from actively coming out of the through hole. Therefore, after the beam reinforcement is inserted into the through hole, it can be directly welded. The setting of the limiting wheel 20 facilitates the initial positioning of the beam reinforcement.

[0064] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An optimized construction method at the joint of a large cross-section beam column, characterized by: Includes the following steps: (1) Determine the arrangement of beam reinforcement: Based on the prestressed duct, determine the position and distribution of the supporting stirrups, longitudinal bars and stirrups to ensure that the prestressed corrugated pipe can pass smoothly in the beam; (2) Establishment of joint models for steel columns and prestressed beams and columns: (2-1) Determine the connection relationship: Use BIM to build the node model of steel column and prestressed beam. Find the positional relationship between the beam reinforcement, prestressed corrugated pipe and steel column by comparing the model. Determine the connection relationship between each beam reinforcement and steel column from the three connection relationships of web passing through, outside bypassing and flange connection. (2-2) For longitudinal and transverse prestressed beams, the reinforcement bars form a staggered layer relationship between upper and lower layers; (2-3) For parallel multi-row beam reinforcement with flange connection, one row is welded to the steel column flange with a connecting plate, and the other rows are mechanically connected to the steel column flange with a rebar connector; (2-4) Based on the determined connection relationship between the beam reinforcement, prestressed corrugated pipe and steel column, determine the position of the reserved holes on the web of the steel column and the position of the connecting plate and connector on the flange of the steel column; The connecting plate has a flange on the opposite side of the side welded to the flange of the steel column. The flange faces the side of the connecting plate that is welded to the beam reinforcement. The flange has a through hole for a single beam reinforcement to pass through. A slot leading to the center of the through hole is provided on the outer edge of the flange. A limiting wheel is provided in the slot. The limiting wheel is rotatably connected to the side wall of the slot by a pin. A ratchet is provided on one side of the limiting wheel. A limiting structure is provided on the outer side of the flange. The limiting structure is located on the side where the ratchet is located. The limiting structure includes a mounting plate welded to the flange. The middle of the mounting plate is raised to form a mounting groove. A limiting post is installed in the mounting groove. A compression spring is installed in the mounting groove to press the limiting post against the ratchet. Through the cooperation of the limiting post and the ratchet, the limiting wheel can only rotate in one direction. The outer circumference of the limiting wheel has crisscrossing anti-slip patterns.

2. The method of optimizing construction at a large cross-section beam column joint according to claim 1, wherein: In step (2-2), the beam reinforcement bars that are staggered in different directions are at least one steel bar diameter apart.

3. The method of optimizing construction at a large cross-section beam column joint according to claim 2, wherein: In steps (2-3), the elevation of the connecting plate or rebar splice connecting the beam bars that are staggered in different directions is at least one rebar diameter away from each other.

4. The method of optimizing construction at a large cross-section beam column joint of claim 3, wherein: Step (2-3) The connecting plate and rebar connector that connect the beam reinforcement in the same direction and at the same level and are located on opposite sides of the flange are set at the same elevation.

5. The method of optimizing construction at a large cross-section beam column joint according to claim 4, wherein: The steel column in step (2) is welded from an I-beam and two T-beams. The webs of the two T-beams are welded to both sides of the web of the I-beam to form a steel column with a cross-section in the shape of a grid.

6. The method of optimizing construction at a large cross-section beam column joint of claim 5, wherein: In step (2-1), for the prestressed corrugated pipe that is directly opposite and perpendicular to the flange of the steel column at the node between the prestressed beam and the steel column, the prestressed corrugated pipe at this location is selected to pass through the web between two adjacent flanges of the steel column.

7. The method of optimizing construction at a large cross-section beam column joint of claim 5, wherein: It also includes step (3) pre-processing of steel columns, welding of steel columns, welding of pre-drilled holes in steel columns and welding of connecting plates and connectors on the wing plates of steel columns are completed in the factory.

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