Extension structure based on existing raft foundation
By using the design of connection parts, shears and welded reinforcement rods in the raft reconstruction project, the problem of damage to the original structure is solved, the integrity and safety of the building structure are ensured, construction costs are reduced, and efficient expansion effect.
Patent Information
- Application Number
- CN202420810967.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-18
- Publication Date
- 2024-12-10
- Estimated Expiration
- 2034-04-18
AI Technical Summary
In the raft reconstruction project, it is difficult for the existing technology to avoid direct damage, invisible damage and vibration damage to the original structure, and the reinforcement bar planting and binding process are complex, which affects the integrity and safety of the building structure.
Adopt an expanded structure based on the existing raft foundation. By setting up connections, shear-resistant and welded reinforcement rods on the side of the original raft structure, the fixed connection between the old and new structures is ensured, the shear-resistant and integrity are improved, and the original structure is reduced. damage.
It effectively avoids demolition and reconstruction problems, ensures the integrity and safety of the building structure, reduces construction costs, and improves the safety and efficiency of construction.
Smart Images
Figure CN222140151U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of building reconstruction construction, in particular to an expansion structure based on an existing raft foundation. Background Art
[0002] The raft reconstruction project includes both the partial demolition of the original raft and the expansion work on the original raft foundation. Due to the special construction, high quality requirements, and small site, it is very easy to cause direct damage to the undemolished structure, invisible damage (cracks in the structure), and vibration damage during the demolition work during the reconstruction and construction process. Therefore, the demolition method is the key consideration for the raft reconstruction. In addition, due to the complexity of the steel bars in the raft and the relatively small area after the raft is demolished, the raft steel bar cutting, binding, welding, planting and manual operation are relatively difficult. Therefore, the steel bar planting and binding during the expansion operation are also the difficulties of the raft reconstruction project. After the raft reconstruction, due to the change of structure, the elevator shaft and elevator sump need to be rebuilt, the basement outer wall needs to be demolished and rebuilt, and the shear wall and constraint edge member position change needs to be reconstructed. Therefore, under the principle of minimizing the damage to the original structure, the construction of the reconstruction structure based on the existing raft foundation is a construction problem that needs to be solved urgently in the raft reconstruction project. In the existing raft reconstruction construction, usually one side of the original raft is roughened and connected with steel bars, and the new building structure is directly constructed in the end area. This method has poor stability in the connection area and poor integrity of the building structure after construction, which affects the safety of the building structure. Utility Model Content
[0003] The utility model aims to provide an expansion structure based on an existing raft foundation, which can be expanded on the basis of the original structure, avoiding the problem of demolition and reconstruction, and reducing damage to the original structural foundation, ensuring the integrity and safety of the building structure, effectively reducing construction costs, and having strong scalability.
[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:
[0005] A construction extension structure based on an existing raft foundation comprises an original raft structure, wherein the original raft structure comprises original bottom steel bars, original top steel bars, an original concrete layer cast on the original bottom steel bars and the original top steel bars, and an original waterproof layer arranged on the bottom of the original bottom steel bars; a connection portion is arranged on one side of the original raft structure, an outward-expanded raft structure is arranged on the connection portion and an extension of the connection portion, and a shear member is arranged between the original raft structure and the outward-expanded raft structure; a bottom lap groove is arranged at the bottom of the original raft structure, the outward-expanded raft structure comprises an outward-expanded bottom steel bar, an outward-expanded top steel bar, an outward-expanded concrete layer cast on the outward-expanded bottom steel bars and the outward-expanded top steel bars, and an outward-expanded waterproof layer arranged on the bottom of the outward-expanded bottom steel bars, the original top steel bars are fixedly connected to the outward-expanded top steel bars, the original bottom steel bars are fixedly connected to the outward-expanded bottom steel bars, and the original waterproof layer is overlapped and connected to the outward-expanded waterproof layer.
[0006] Preferably, the width of the connecting portion is 1000 mm.
[0007] Preferably, the shear members are made of steel bars, and the depth of the shear members located in the original raft structure is less than the depth of the shear members located in the outwardly expanded raft structure.
[0008] Preferably, a plurality of the anti-shear members are provided, and the plurality of anti-shear members are arranged in a plum blossom shape.
[0009] Preferably, the overlapping area between the original top steel bar and the outwardly expanded top steel bar is located above the connecting portion.
[0010] Preferably, the overlapping area between the original bottom layer of steel bars and the outwardly expanded bottom layer of steel bars is located in the bottom overlapping groove.
[0011] Preferably, the overlapping area between the original waterproof layer and the externally expanded waterproof layer is located below the bottom of the connecting portion and the bottom overlapping groove.
[0012] Preferably, the original top steel bar and the outwardly expanded top steel bar are fixedly connected by welding, and a plurality of sections of first welded reinforcement rods are arranged on the original top steel bar and the outwardly expanded top steel bar.
[0013] Preferably, the original bottom steel bars and the outwardly expanded bottom steel bars are fixedly connected by welding, and a second welded reinforcement rod is provided on the original bottom steel bars and the outwardly expanded bottom steel bars, and the length of the second welded reinforcement rod is slightly shorter than the depth of the bottom lap groove.
[0014] Preferably, diagonal brace reinforcement rods are provided on the anti-shear members, and the diagonal brace reinforcement rods fixedly connect a plurality of anti-shear members.
[0015] In the utility model, the structure now has a connection portion formed by chiseling out a designated width on one side of the original raft structure, and retaining the original top steel bars above the connection portion for fixed connection with the expanded top steel bars of subsequent construction. The connection length is large, which enhances the integrity of the structure. The bottom lap groove is used for fixed connection construction of the original bottom steel bars and the expanded bottom steel bars, so that the newly constructed raft structure can be fixedly connected to the top and bottom of the original raft structure, ensuring the structural strength of the connection between the new and old structures. The shear-resistant parts are provided to improve the shear resistance of the new and old raft structures at the connection point, avoiding the situation where the raft structure is broken due to local settlement, and ensuring the safety of the structure. This solution adopts expansion based on the original structure, avoiding the problem of demolition and reconstruction, and reducing damage to the foundation of the original structure, ensuring the integrity and safety of the building structure, and effectively reducing construction costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a schematic cross-sectional view of the overall structure of the utility model;
[0017] In the figure: 1. original raft structure; 2. connection part; 3. outward-expanded raft structure; 4. shear member; 5. diagonal bracing reinforcement rod; 6. bottom lap groove; 7. first welded reinforcement rod; 8. second welded reinforcement rod; 10. bottom steel bar; 11. original top steel bar; 12. original concrete layer; 13. original waterproof layer; 30. outward-expanded bottom steel bar; 31. outward-expanded top steel bar; 32. outward-expanded concrete layer; 33. outward-expanded waterproof layer. DETAILED DESCRIPTION
[0018] The utility model is further described below in conjunction with the accompanying drawings:
[0019] like Figure 1 The expansion structure based on the existing raft foundation shown in the figure includes the original raft structure 1, the original raft structure 1 includes the original bottom steel bar 10, the original top steel bar 11, the original concrete layer 12 cast on the original bottom steel bar 10 and the original top steel bar 11, and the original waterproof layer 13 arranged below the bottom of the original bottom steel bar 10. A connection part 2 is arranged on one side of the original raft structure 1. The area corresponding to the connection part 2 is the area to be chiseled out on the side of the original raft structure 1 to be expanded. The cutting of this area can be carried out by water drilling. Before construction, the original top steel bar 11 located above the connection part 2 needs to be bent upward without damaging the original top steel bar 11. In this embodiment, the width of the connection part 2 is 1000mm. Of course, the width of the connection part 2 can also be set to 1200mm, 900mm or other values according to the requirements of structural strength.
[0020] An outward-expanded raft structure 3 is provided at the connection part 2 and the extension part of the connection part 2, and a shear member 4 is provided between the original raft structure 1 and the outward-expanded raft structure 3, and the shear member 4 improves the shear resistance between the original raft structure 1 and the outward-expanded raft structure 3. In this embodiment, the shear member 4 is made of steel bars, and the diameter of the steel bars is not less than the diameter of the original bottom steel bars 10 or the original top steel bars 11, and the depth of the shear member 4 in the original raft structure 1 is less than the depth in the outward-expanded raft structure 3. A plurality of shear members 4 are provided, and the plurality of shear members 4 are provided in a plum blossom shape or in a rectangular array. A diagonal brace reinforcement rod 5 is provided on the shear member 4, and the diagonal brace reinforcement rod 5 fixes and connects the plurality of shear members 4, thereby improving the connection strength. Specifically, the shear member 4 is located in the original raft structure 1 at a depth 16 times the diameter of the shear member 4, and the shear member 4 is located in the outward-expanded raft structure 3 at a depth 20 times the diameter of the shear member 4.
[0021] A bottom lap groove 6 is provided at the bottom of the original raft structure 1 by chiseling. The outward-expanded raft structure 3 includes an outward-expanded bottom steel bar 30, an outward-expanded top steel bar 31, an outward-expanded concrete layer 32 cast on the outward-expanded bottom steel bar 30 and the outward-expanded top steel bar 31, and an outward-expanded waterproof layer 33 provided at the bottom of the outward-expanded bottom steel bar 30. The original top steel bar 11 and the outward-expanded top steel bar 31 are fixedly connected by welding. Multiple sections of first welded reinforcing rods 7 are provided on the original top steel bar 11 and the outward-expanded top steel bar 31. The multiple sections of first welded reinforcing rods 7 are welded and connected to the original top steel bar 11 and the outward-expanded top steel bar 31, thereby improving the connection strength. The overlap area between the original top steel bar 11 and the outward-expanded top steel bar 31 is located above the connecting portion 2.
[0022] The original bottom steel bar 10 and the outer bottom steel bar 30 are fixedly connected by welding, and the overlapping area of the original bottom steel bar 10 and the outer bottom steel bar 30 is located in the bottom overlapping groove 6. A second welded reinforcing rod 8 is fixedly arranged on the original bottom steel bar 10 and the outer bottom steel bar 30 by welding, and the length of the second welded reinforcing rod 8 is slightly shorter than the depth of the bottom overlapping groove 6 or is adapted to the depth of the bottom overlapping groove 6.
[0023] The original waterproof layer 13 is connected with the external waterproof layer 33 by overlapping, and the overlapping area of the original waterproof layer 13 and the external waterproof layer 33 is located below the bottom of the connecting portion 2 and the bottom overlapping groove 6. The overlapping length of the original waterproof layer 13 and the external waterproof layer 33 is located at the bottom of the entire demolition construction area to avoid damage to the original waterproof layer 13 during the construction process and ensure the waterproof ability of the structure after construction. The external waterproof layer 33 uses a 4mm thick waterproof roll.
[0024] During the construction of the outward-expanded raft structure 3, the chiseled section of the outward-expanded raft structure 3 needs to be roughened, and the outward-expanded concrete layer 32 of the extended part of the connection part 2 is constructed first. The outward-expanded concrete layer 32 is cast with C40 slightly-expanded fine stone concrete. After the strength of the outward-expanded concrete layer 32 of this part reaches 80% of the preset value, the outward-expanded concrete layer 32 corresponding to the connection part 2 is cast, thereby realizing the overall connection between the original raft structure 1 and the outward-expanded raft structure 3.
[0025] The above embodiments are only some descriptions of the concept and implementation of the utility model, and are not intended to limit the concept and implementation of the utility model. Under the concept of the utility model, technical solutions that have not been substantially changed are still within the scope of protection.
Claims
1. An expansion structure based on an existing raft foundation, comprising an original raft structure, wherein the original raft structure comprises an original bottom steel bar, an original top steel bar, an original concrete layer cast on the original bottom steel bar and the original top steel bar, and an original waterproof layer arranged on the bottom of the original bottom steel bar, characterized in that: A connecting portion is arranged on one side of the original raft structure, an outward-expanded raft structure is arranged on the connecting portion and an extended portion of the connecting portion, and a shear member is arranged between the original raft structure and the outward-expanded raft structure; a bottom lap groove is arranged at the bottom of the original raft structure, the outward-expanded raft structure comprises an outward-expanded bottom layer of steel bars, an outward-expanded top steel bar, an outward-expanded concrete layer cast on the outward-expanded bottom layer of steel bars and the outward-expanded top steel bar, and an outward-expanded waterproof layer arranged on the bottom of the outward-expanded bottom layer of steel bars, the original top steel bar is fixedly connected to the outward-expanded top steel bar, the original bottom steel bar is fixedly connected to the outward-expanded bottom steel bar, and the original waterproof layer is overlapped and connected to the outward-expanded waterproof layer.
2. The expansion structure based on the existing raft foundation according to claim 1, characterized in that: The width of the connecting portion is 1000 mm.
3. The expansion structure based on the existing raft foundation according to claim 1, characterized in that: The shear member is made of steel bars, and the depth of the shear member located in the original raft structure is less than the depth of the shear member located in the outwardly expanded raft structure.
4. The expansion structure based on the existing raft foundation according to claim 1 or 3, characterized in that: The anti-shear members are arranged in plurality, and the plurality of anti-shear members are arranged in a plum blossom shape.
5. The expansion structure based on the existing raft foundation according to claim 1, characterized in that: The overlapping area between the original top steel bar and the outwardly expanded top steel bar is located above the connecting portion.
6. The expansion structure based on the existing raft foundation according to claim 1, characterized in that: The overlapping area between the original bottom layer steel bars and the outwardly expanded bottom layer steel bars is located in the bottom overlapping groove.
7. The expansion structure based on the existing raft foundation according to claim 1, characterized in that: The overlapping area between the original waterproof layer and the externally expanded waterproof layer is located below the bottom of the connecting portion and the bottom overlapping groove.
8. The expansion structure based on the existing raft foundation according to claim 1 or 5, characterized in that: The original top steel bar and the outward-expanded top steel bar are fixedly connected by welding, and a plurality of sections of first welded reinforcing rods are arranged on the original top steel bar and the outward-expanded top steel bar.
9. The expansion structure based on the existing raft foundation according to claim 1 or 6, characterized in that: The original bottom steel bars and the outwardly expanded bottom steel bars are fixedly connected by welding, and a second welded reinforcement rod is arranged on the original bottom steel bars and the outwardly expanded bottom steel bars, and the length of the second welded reinforcement rod is slightly shorter than the depth of the bottom lap groove.
10. The expansion structure based on the existing raft foundation according to claim 1, characterized in that: A diagonal brace reinforcement rod is arranged on the anti-shear member, and the diagonal brace reinforcement rod fixes and connects a plurality of anti-shear members.