Construction method for underpinning and reinforcing beam columns in reconstruction project

Abstract

The application discloses a construction method for beam column underpinning and reinforcement in reconstruction engineering, which comprises the following steps: S1) on-site line positioning, checking and canceling structural columns, adding structural columns and setting positions of frame beams to be underpinned; S2) setting temporary supports to support frame beams to be underpinned; S3) removing structural columns to be canceled; S4) erecting bent formwork, binding steel bars; constructing added structural columns, reinforcing and lengthening one side of frame beams and connecting to the added structural columns; S5) after concrete curing is completed, the bent formwork is used as temporary supports; S6) binding steel bars of structural columns to be added, and reinforcing and constructing the other side of frame beams to be underpinned; and S7) after concrete curing is completed, the bent formwork is removed. The construction method for beam column underpinning and reinforcement in reconstruction engineering can guarantee structural stability, improve construction safety, save material turnover, save construction period and cost.

Description

Technical Field

[0001] This invention relates to a method for beam-column replacement and reinforcement, and more particularly to a construction method for beam-column replacement and reinforcement in reconstruction projects. Background Technology

[0002] In the context of urban renewal, changes in building circulation often necessitate the relocation of structural columns. If the relocation distance is excessive, an additional structural column must be added within the beam span, altering the building's structural load-bearing system. In such cases, demolition of the existing structural column and the entire frame beam is required before reconstruction, resulting in high costs. However, in reality, each floor of a building often requires changes to the building's circulation, necessitating the removal of structural columns and frame beams on each floor. This method is risky and costly. Furthermore, it requires extensive temporary supports around the demolished structures. The drawback is that these temporary supports occupy significant space, limiting operational space and hindering the reinforcement binding and concrete pouring of the new structural columns and reconstructed frame beams.

[0003] Therefore, it is urgent to solve the construction problems in beam and column replacement and reinforcement in the reconstruction project, such as high risk, high cost, and the obstruction of construction by temporary support. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a construction method for beam and column replacement and reinforcement in reconstruction projects, which can ensure structural stability, improve construction safety, save material turnover, and save construction time and cost.

[0005] The technical solution adopted by this invention to solve the above-mentioned technical problems is to provide a construction method for beam-column replacement and reinforcement in a reconstruction project, including the following steps: S1) According to the design drawings, lay out and locate the structural columns to be cancelled, the structural columns to be added, and the frame beams to be replaced on site; S2) Set up temporary supports to support the frame beams to be replaced; S3) Remove the structural columns to be cancelled by mechanical chiseling, manual chiseling, or static cutting methods; S4) Erect scaffolding and formwork, and tie the reinforcing bars; after the construction of the newly added structural columns is completed, reinforce one side of the frame beam and extend it to connect to the newly added structural columns; S5) After the concrete has cured, use the scaffolding and formwork as temporary supports; remove the temporary supports set in step S2; S6) Tie the reinforcing bars of the newly added structural columns and complete the reinforcement construction of the frame beams to be replaced on the other side; S7) After the concrete has cured, remove the scaffolding and formwork to complete the beam-column replacement and reinforcement construction.

[0006] Furthermore, step S1 first verifies the structural columns that need to be removed from the upper structure and secondary structure.

[0007] Furthermore, in step S2, steel pipes with a diameter of 48mm and a wall thickness of 3mm are used to erect temporary supports by connecting them with horizontal bars in groups of a certain number of uprights.

[0008] Furthermore, the upright is provided with a top support and a wooden beam.

[0009] Furthermore, steps S4 and S6 include breaking the concrete of the frame beam that needs to be replaced, retaining the longitudinal reinforcement of the original frame beam and enlarging the cross-section during construction. Step S4 involves welding to extend the longitudinal reinforcement of the original frame beam; then, concrete is poured to form a reinforced frame beam, and the extension and thickened part of the reinforced frame beam have the same cross-section.

[0010] Furthermore, the concrete for the extension and thickening of the frame beam and the concrete for the newly added structural columns are poured simultaneously.

[0011] Furthermore, in step S3, all structural columns that need to be removed on all floors are demolished in one go from top to bottom.

[0012] Furthermore, in steps S4 and S6, all floor frame beams are extended and reinforced on the same side at one time and connected to the newly added structural columns.

[0013] Compared with existing technologies, the present invention has the following advantages: The construction method for beam-column replacement and reinforcement in reconstruction projects provided by the present invention optimizes the construction sequence, requiring only the installation of temporary supports. These temporary supports, along with the original and newly added structural columns, work together to transfer loads and support the superstructure. The present invention employs a reinforcement method that increases the beam cross-section, avoiding the removal of an entire original frame beam, thus saving time and costs. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the frame beams and structural columns in the project to be renovated according to the present invention; Figure 2 This is a schematic diagram of the structure after one side of the structural column is removed in the reconstruction project of this invention; Figure 3 This is a schematic diagram of the reinforcement structure for extending one side of the first-floor frame beam in the project to be renovated according to the present invention; Figure 4 This is a schematic diagram of the extension and reinforcement structure of the second-floor frame beam on one side in the reconstruction project of this invention; Figure 5 This is a schematic diagram of the structure of the other side frame beam after it is extended and reinforced in the reconstruction project of this invention; Figure 6 This is a schematic diagram of the temporary support structure used in this invention; Figure 7 For along Figure 6A schematic diagram of the cross-sectional structure of line AA in the middle. Detailed Implementation

[0015] The present invention will now be further described with reference to the accompanying drawings and embodiments.

[0016] The construction method for beam-column replacement and reinforcement in reconstruction projects provided by this invention includes the following steps: Step 1: Based on the design drawings, lay out and verify the locations of structural columns to be removed, structural columns to be added, and frame beams to be replaced on-site. Any structures in the superstructure and secondary structure that need to be demolished should be removed first to reduce the load on the superstructure. For example... Figure 1 The structural column 1 to be retained, the frame beam 2 to be replaced, and the structural column 3 to be removed are also included. The frame beam 2 to be replaced consists of two beams on the upper and lower floors, totaling two beams.

[0017] Step 2: Set up temporary supports 4 to support the frame beam 2 that needs to be replaced. Temporary supports 4 can be made of steel pipes with a diameter of 48mm and a wall thickness of 3mm. They are erected in groups of a certain number of uprights 10, with top supports 9 and timber beams at the top of each upright 10. Each group of temporary supports 4 is connected by horizontal bars 11. Figure 6 and Figure 7 As shown.

[0018] Step 3: Once construction conditions permit, use methods such as mechanical chiseling, manual chiseling, or static cutting to remove the structural columns 3 that need to be eliminated from all floors of the building, from top to bottom. For example... Figure 2 The two structural columns on the upper and lower floors are 3.

[0019] Step 4: After the structural columns are removed, retain the longitudinal reinforcement of the original beams at the beam-column joints. Extend the longitudinal reinforcement of the original frame beams by welding, erect scaffolding and formwork, tie the reinforcement of the new structural columns, enlarge the cross-section of some frame beams, and reserve reinforcement for the enlarged cross-section. Simultaneously, extend the original frame beams, ensuring the extended beams have the same cross-section as the enlarged beams, and then pour concrete. Figure 3 The thickened frame beam 7 and frame beam extension 6 are shown. Repeat the above steps until all floors are completed, as follows: Figure 4 As shown.

[0020] Step 5: After the concrete has cured, do not remove the formwork scaffolding. Use the formwork scaffolding (scaffolding) as temporary support. Remove the temporary support on the other side. Position the structural columns to be added as described in Step 1. Similarly, use mechanical chiseling, manual chiseling, or static cutting methods to remove part of the frame beams (only break the concrete; retain the original longitudinal reinforcement). See... Figure 4 Frame beam 2 in the middle.

[0021] Step 6: Tie the reinforcing bars for the newly added structural columns, extend the pre-reserved beam reinforcement bars from Step 4 to complete the reinforcement construction of the enlarged section of the frame beams, and pour the concrete simultaneously with the newly added structural columns. Repeat the above steps until all floors are completed. See Figure 5 The thickened frame beam 7 and the newly added structural column 8 on the other side.

[0022] Step 7: After the concrete has cured, remove the formwork and complete the beam and column replacement and reinforcement construction. Figure 5 Structural column 1 is the original retained structural column, while structural columns 5 and 8 are newly added structural columns. The frame beam that needed to be replaced was enlarged and became the thickened frame beam 7, and an extension 6 of the frame beam was added.

[0023] Preferably, the formwork support frame (scaffolding) is not dismantled in step 5. The formwork support frame (scaffolding) is used as a temporary support, which saves material turnover and avoids the repeated erection of temporary supports. At the same time, by avoiding the erection of full-span temporary supports, the construction problems such as the small space and insufficient working surface caused by full-span support frames are solved.

[0024] Preferably, the method of increasing the beam cross-section for reinforcement in step 4 does not require the removal of the entire frame beam, reducing waste removal and minimizing the amount of concrete and steel reinforcement used, thus saving costs.

[0025] Preferably, in steps 2 and 5, only some temporary supports need to be set up. The temporary supports, the original or newly added structural columns, and the formwork frame (scaffolding) can all play the role of transferring loads and supporting the upper structure, thus ensuring structural stability and improving construction safety.

[0026] Preferably, in step 3, all structural columns that need to be removed on all floors can be removed at once from top to bottom, and in steps 4 and 6, all floors can be completed at once, which shortens the construction cycle and saves time.

[0027] In summary, this invention provides a construction method for beam-column replacement and structural reinforcement in renovation projects, which can serve as a reference for similar construction projects, ensuring the smooth progress of projects, and has the following advantages: 1. By optimizing the construction sequence, only some temporary supports are needed. The temporary supports, the original or newly added structural columns, and the formwork (scaffolding) all play the role of transferring loads and supporting the superstructure, thus ensuring structural stability and improving construction safety.

[0028] 2. Utilizing formwork scaffolding (framework) as temporary support saves on material turnover and avoids the repeated erection of temporary supports. Furthermore, by avoiding the need for full-span temporary supports, it solves construction problems such as limited floor space and insufficient working surfaces caused by full-span support scaffolding.

[0029] 3. Because this invention uses a method of increasing the beam cross-section for reinforcement, it does not require the demolition of the entire frame beam, reducing waste removal and minimizing the amount of concrete and steel reinforcement used, thus saving costs.

[0030] 4. This invention can remove all structural columns that need to be eliminated from all floors at once, saving construction time.

[0031] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications and improvements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be defined by the claims.

Claims

1. A construction method for beam-column replacement and reinforcement in a reconstruction project, characterized in that, Includes the following steps: S1) Based on the design drawings, lay out and locate the structural columns that need to be cancelled, the structural columns that need to be added, and the frame beams that need to be replaced on site. S2) Install temporary supports to hold up the frame beams that need to be replaced; S3) Remove the structural columns that need to be eliminated by mechanical chiseling, manual chiseling, or static cutting methods; S4) Erect scaffolding and formwork, and tie steel bars; after the construction of the newly added structural column is completed, reinforce one side of the frame beam and extend it to connect to the newly added structural column; S5) After the concrete has cured, use the scaffolding as a formwork support; remove the temporary support set in step S2. S6) Tie the reinforcing bars of the structural columns that need to be added, and complete the reinforcement construction of the frame beam that needs to be replaced on the other side; S7) After the concrete has cured, remove the scaffolding and formwork, and complete the beam and column replacement and reinforcement construction; Steps S4 and S6 include breaking the concrete of the frame beam that needs to be replaced, retaining the longitudinal reinforcement of the original frame beam and enlarging the cross section. Step S4 involves welding and extending the longitudinal reinforcement of the original frame beam; then pouring concrete to form a reinforced frame beam, the extension and thickened part of the reinforced frame beam having the same cross section. The concrete for the extension and thickening of the frame beam and the concrete for the newly added structural columns were poured simultaneously. In step S3, all structural columns that need to be removed are demolished from top to bottom in one go. In steps S4 and S6, all floor frame beams are reinforced on the same side and connected to the newly added structural columns in one go.

2. The construction method for beam-column replacement and reinforcement in the reconstruction project as described in claim 1, characterized in that, Step S1 first verifies the structural columns that need to be removed from the upper and secondary structures.

3. The construction method for beam-column replacement and reinforcement in the reconstruction project as described in claim 1, characterized in that, Step S2 uses steel pipes with a diameter of 48mm and a wall thickness of 3mm, which are erected in groups of a certain number of uprights and connected by horizontal bars to form temporary support.

4. The construction method for beam-column replacement and reinforcement in the reconstruction project as described in claim 3, characterized in that, The upright is equipped with a top support and wooden blocks.

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