Construction method for burying tower crane foundation in raft

Abstract

The invention relates to the technical field of building engineering construction, in particular to a construction method for burying a tower crane foundation in a raft. The tower crane foundation can be directly used as a part of the raft foundation, secondary construction of the tower crane foundation on the raft foundation is not needed, and equivalently, part of the raft foundation is used for reinforcement to obtain the tower crane foundation; the manufacturing cost of the tower crane foundation can be greatly reduced, and the project amount is reduced; and the tower crane foundation can be constructed in advance, a tower crane can be installed for use after construction is completed, the construction period is shortened, meanwhile, the raft foundation formed through pouring and the tower crane foundation are connected into a whole, and the tower crane foundation is safer and more reliable.

Description

Technical Field

[0001] The invention relates to the technical field of building engineering construction, and in particular to a construction method in which a tower crane foundation is buried in a raft slab. Background Art

[0002] When large-scale group engineering construction is carried out, the first thing to solve is the vertical transportation problem. Tower cranes are the preferred vertical transportation tool in the current construction industry. In recent years, with the continuous development of my country's metallurgical industry, metallurgical construction projects have become common. Considering factors such as on-site construction sites, secondary handling of building materials, and transportation distance within the site, tower cranes are often erected next to the main building, and the tower crane foundation is generally located on the foundation or pile foundation. However, for tower cranes with small and complex on-site construction sites that cannot meet the rotation radius during installation, the tower crane will be placed on the upper part of the raft foundation to meet the construction requirements. However, in actual application, the tower crane foundation is set on the upper side of the raft foundation that has been constructed. This construction sequence requires waiting for the raft foundation construction to be completed before the tower crane foundation can be installed. The construction period is relatively long, so a new construction method is needed to solve the problems in the existing technology. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a construction method for burying a tower crane foundation in a raft slab, so as to achieve the technical effect of greatly reducing the engineering workload of the tower crane foundation and shortening the construction period.

[0004] To achieve this technical purpose, the present invention adopts the following scheme: A construction method for burying a tower crane foundation in a raft slab is carried out according to the following steps: S1. Locate the tower crane foundation in the construction drawings and combine it with the superstructure; S2. Before excavating the foundation pit or constructing the basement structure raft, determine the plane dimensions of the tower crane foundation; S3, the cushion layer of the raft slab casting area and the tower crane foundation casting area is cast as a whole; S4. Lay a waterproof layer at the bottom and joints of the tower crane foundation pouring area; S5. Tie the steel bars. Tie the lower steel bars first, then the upper steel bars. After the upper steel bars are tied, tie the tension bars between the upper and lower steel bars. S6. After the steel bar binding is completed, check the binding quality. If the quality is qualified, set the tower crane installation control line on the upper steel bar, and then install the anchor screws and positioning plates according to the control line. After installation, calibrate the position and verticality of the anchor screws; S7, install the water stop steel plate at the connection between the tower crane foundation casting area and the raft foundation casting area; a part of the water stop steel plate extends into the tower crane foundation casting area, and another part extends into the raft foundation casting area to cover the construction joint; S8. Set up the casting formwork, use the wire mesh as the casting formwork, and fix it with fixing parts; S9. Pour concrete in the tower crane foundation pouring area. The tower crane can be installed only when the concrete strength reaches more than 80%. After the initial height of the tower crane is installed, the tower crane body and the tower crane foundation should be connected to the lightning protection grounding.

[0005] Compared with the prior art, the present invention has the following beneficial effects: In the present invention, after the tower crane foundation is used, it can be directly used as a part of the raft foundation, and there is no need to construct the tower crane foundation for the second time on the raft foundation, which is equivalent to using part of the raft foundation to strengthen the tower crane foundation; it can greatly reduce the cost of the tower crane foundation and reduce the amount of engineering; and the tower crane foundation can be constructed in advance, and the tower crane can be installed for use after the construction is completed, which shortens the construction period. At the same time, the raft foundation formed by pouring is connected with the tower crane foundation, making the tower crane foundation safer and more reliable.

[0006] Further, the preferred embodiment of the present invention is: In step S5, when tying the upper layer of steel bars, a steel bar saddle should be set up first to determine the spacing between the upper and lower layers of steel bars.

[0007] When installing the anchor bolts in step S6, the anchor bolts on each corner of the corresponding tower crane foundation should be positioned using a positioning plate, that is, the upper end of the anchor bolt is passed through the positioning plate and temporarily fixed with a nut. The upper end of the anchor bolt is covered with a plastic tube or wrapped with a plastic film to prevent the upper end of the anchor bolt from being contaminated.

[0008] The vertical height of the water-stop steel plate in step S7 is located at 1 / 2 of the foundation height.

[0009] In step S8, the horizontal spacing between the fixings is less than or equal to 200 mm, and the fixings are made of angle steel L50*5 or structural steel bars, which are removed after pouring is completed. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a schematic cross-sectional view of the tower crane foundation structure in the present invention; Figure 3 This is a schematic diagram of the tower crane foundation plane; The markings in the figure are: 1. Raft slab casting area; 2. Tower crane foundation casting area; 3. Structural steel bars; 4. Waterstop steel plate; 5. Connectors; 6. Positioning plates; 7. Anchor screws; 8. Fixing parts. DETAILED DESCRIPTION

[0011] In order to fully understand the purpose, features and effects of the present invention, the present invention is described in detail through the following specific implementation methods, but the present invention is not limited thereto.

[0012] A construction method for burying a tower crane foundation in a raft slab is carried out according to the following steps: S1. Locate the tower crane foundation in the construction drawings and combine it with the superstructure.

[0013] S2. Before excavating the foundation pit or constructing the basement structure raft, determine the plane size of the tower crane base and its position on the raft or basement structure raft.

[0014] S3, the cushion layers of the raft slab casting area 1 and the tower crane foundation casting area 2 are cast as a whole.

[0015] S4. Lay a waterproof layer at the bottom and interface of the tower crane foundation pouring area 2.

[0016] S5. Tie the steel bars. Tie the lower steel bars first. When tying the lower steel bars, raise the bottom steel bars to ensure that there is a certain distance between the bottom steel bars and the ground. After the lower steel bars are tied, tie the upper steel bars. When tying the upper steel bars, set up steel horse stools in advance to ensure the spacing between the upper and lower steel bars. After the horse stools are set up, tie the upper steel bars. After the upper steel bars are tied, tie the tension bars between the upper and lower steel bars.

[0017] S6. After the steel bar binding is completed, check the binding quality. If the quality is qualified, set the tower crane installation control line on the upper steel bar, and then install the anchor bolt 7 and the positioning plate 6 according to the control line. When installing the anchor bolt 7, the anchor bolt on each corner of the corresponding tower crane foundation should be positioned with the positioning plate 6, that is, the upper end of the anchor bolt 7 should be passed through the positioning plate 6 and temporarily fixed with a nut. The upper end of the anchor bolt 7 is covered with a plastic tube or wrapped with a plastic film to prevent the upper end of the anchor bolt from being contaminated; The two positioning plates 6 are connected by steel components to ensure the accuracy and reliability of the overall position of the anchor screw 7. After installation, the position and verticality of the anchor screw 7 should be corrected to ensure the installation accuracy of the tower crane standard section.

[0018] S7. Install the waterstop steel plate 4 at the connection between the tower crane foundation casting area 2 and the raft slab casting area 1. The vertical height of the waterstop steel plate 4 is located at 1 / 2 of the foundation height, and the upper and lower ends of the waterstop steel plate 4 are respectively fixed by connecting pieces 5. The connecting piece 5 in this embodiment is L50*5 or steel bar. A part of the waterstop steel plate 4 extends into the tower crane foundation casting area 2, and the other part extends into the raft slab casting area 1. The waterstop steel plate 4 covers the construction joint.

[0019] S8. Support the casting formwork, use wire mesh as the casting formwork, and fix it with fixing parts 8. In this embodiment, the fixing parts 8 can be L50*5 or steel bars. The horizontal spacing between the horizontal and vertical fixing parts 8 is less than or equal to 200mm. The fixing parts 8 are removed after the casting is completed.

[0020] S9. Pour concrete in the tower crane foundation pouring area 2. When pouring, prevent the vibrator from colliding with the anchor screw 7 and avoid vibrating the vibrator on the steel bar. When the surface concrete of the tower crane foundation pouring area 2 is applied, a scraper should be used for leveling, and a level ruler should be used to check the horizontality of the tower crane body to ensure the flatness of the tower crane foundation section during installation. After the tower crane foundation is poured, the tower crane can be installed only when its concrete strength reaches more than 80%. After the initial height of the tower crane is installed, the tower crane body and the tower crane foundation should be connected to the lightning protection grounding.

[0021] The present invention can significantly reduce the cost of the tower crane foundation, reduce the amount of engineering work, and the tower crane foundation can be constructed in advance. After the construction is completed, the tower crane can be installed for use, thereby shortening the construction period.

[0022] Finally, it should be noted that the above are only preferred embodiments of the present invention. Of course, those skilled in the art can make changes and modifications to the present invention. If these modifications and variations fall within the scope of the claims of the present invention and their equivalent technologies, they should be considered to be within the scope of protection of the present invention.

Claims

1. A construction method for burying a tower crane foundation in a raft slab is carried out according to the following steps: S1. Locate the tower crane foundation in the construction drawings and combine it with the superstructure; S2. Before excavating the foundation pit or constructing the basement structure raft, determine the plane dimensions of the tower crane foundation; Features: S3, the cushion layer of the raft slab casting area and the tower crane foundation casting area is cast as a whole; S4. Lay a waterproof layer at the bottom and joints of the tower crane foundation pouring area; S5. Tie the steel bars. Tie the lower steel bars first, then the upper steel bars. After the upper steel bars are tied, tie the tension bars between the upper and lower steel bars. S6. After the steel bar binding is completed, check the binding quality. If the quality is qualified, set the tower crane installation control line on the upper steel bar, and then install the anchor screws and positioning plates according to the control line. After installation, calibrate the position and verticality of the anchor screws; S7, install the water stop steel plate at the connection between the tower crane foundation casting area and the raft foundation casting area; a part of the water stop steel plate extends into the tower crane foundation casting area, and another part extends into the raft foundation casting area to cover the construction joint; S8. Set up the casting formwork, use the wire mesh as the casting formwork, and fix it with fixing parts; S9. Pour concrete in the tower crane foundation pouring area. The tower crane can be installed only when the concrete strength reaches more than 80%. After the initial height of the tower crane is installed, the tower crane body and the tower crane foundation should be connected to the lightning protection grounding.

2. The construction method of embedding a tower crane foundation in a raft according to claim 1, characterized in that: In step S5, when tying the upper layer of steel bars, a steel bar saddle should be set up first to determine the spacing between the upper and lower layers of steel bars.

3. The construction method of embedding a tower crane foundation in a raft according to claim 1, characterized in that: When installing the anchor bolts in step S6, the anchor bolts on each corner of the corresponding tower crane foundation should be positioned using a positioning plate, that is, the upper end of the anchor bolt is passed through the positioning plate and temporarily fixed with a nut. The upper end of the anchor bolt is covered with a plastic tube or wrapped with a plastic film to prevent the upper end of the anchor bolt from being contaminated.

4. The construction method of embedding a tower crane foundation in a raft according to claim 1, characterized in that: The vertical height of the water-stop steel plate in step S7 is located at 1 / 2 of the foundation height.

5. The construction method of embedding a tower crane foundation in a raft slab according to claim 1, characterized in that: In step S8, the horizontal spacing between the fixings is less than or equal to 200 mm, and the fixings are made of angle steel L50*5 or structural steel bars, which are removed after pouring is completed.

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