A new station and existing station transfer interface reconstruction construction method and structure
By constructing the upper beams and casting them together as a single unit during the construction phase of the new station's roof slab, and then removing the existing walls after sealing the roof slab to form a C-shaped beam structure, the problem of water intrusion in traditional construction was solved, achieving a safe connection between the new and old stations and controllable construction progress.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- RANKEN RAILWAY CONSTR GROUP
- Filing Date
- 2026-06-04
- Publication Date
- 2026-07-14
AI Technical Summary
In the renovation of interchange nodes between new and existing subway stations, traditional construction methods require the reservation of post-pouring strips, which makes it easy for water to infiltrate existing stations, affecting operational safety and construction progress is greatly affected by the weather. Existing auxiliary measures have failed to fundamentally solve the problem of water intrusion.
During the construction phase of the new station roof slab, the upper beams are first cast integrally with the roof slab. After the roof slab is sealed, the existing walls are demolished, and a C-shaped beam structure is formed by the fixed connection between the lower beams and the upper beams. The post-cast strip is eliminated to ensure the effective connection between the new and old station roof slabs.
This method enables the safe demolition of existing walls without reserving post-pouring strips, cutting off the path of water intrusion, ensuring the operational safety of existing stations, and improving the controllability of construction progress and the reliability of structural connections.
Smart Images
Figure CN122383010A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of building construction, specifically to a construction method and structure for the renovation of transfer interfaces between new and existing railway stations. Background Technology
[0002] With the rapid development of urban rail transit networks, the number of interchange projects between new subway lines and existing operating stations is increasing. At the interface between a new station and an existing station constructed using the open-cut method, to achieve structural continuity, it is usually necessary to demolish part of the existing station's side wall structure and leave a 3-5 meter wide post-cast strip on the roof slab of the new station to facilitate the removal of the demolished walls and the clearing of excavated soil. After the existing walls are demolished and the interface structure is completed, the post-cast strip is then sealed with a second pour.
[0003] However, the aforementioned traditional construction methods pose serious safety hazards. Due to the presence of post-cast strips, the roof slab of the new station cannot be sealed in a timely manner. In cases of underground water pipe network damage or surface runoff during the rainy season, water can easily seep into the existing subway station through the post-cast strips, significantly impacting the normal operation of the existing line and even causing safety accidents. Although the industry has tried auxiliary measures such as temporary shielding and enhanced drainage, none have fundamentally solved the problem of water intrusion. Furthermore, the presence of post-cast strips also restricts the roof slab sealing time, causing construction progress to be significantly affected by weather and uncontrollable pipeline damage. Therefore, how to safely demolish the existing station walls and achieve an effective connection between the old and new station roof slabs without reserving post-cast strips has become a pressing technical challenge in this field. Summary of the Invention
[0004] To address the aforementioned technical issues, the aim is to provide a construction method and structure for the renovation of the transfer interface between a new station and an existing station, which allows for the safe demolition of the existing station walls and the effective connection of the roof slabs of the new and old stations without the need for pre-cast strips.
[0005] This invention is achieved through the following technical solution:
[0006] A construction method for renovating the transfer interface between a new station and an existing station includes the following steps: Step 1: During the construction of the roof slab of the new station, the upper beam at the transfer node interface is constructed first, and the upper beam is cast integrally with the roof slab of the new station to seal the roof slab of the new station; Step 2: After the roof slab is sealed, the wall to be demolished at the transfer node interface of the existing station is removed; Step 3: After the wall is demolished, the lower beam at the transfer node interface is constructed, and the lower beam is fixedly connected to the upper beam to form a complete transfer node interface beam structure, thereby realizing the structural connection between the roof slab of the new station and the roof slab of the existing station.
[0007] The beneficial effects of this invention are that, by constructing the upper beams and casting them integrally with the roof slab during the construction phase of the new station roof slab to seal it, the roof slab of the new station is sealed before the existing walls are demolished. This eliminates the need for post-cast strips, which are required in traditional processes, and cuts off the path for surface water, rainwater, or leaks from damaged pipelines to intrude into the existing operating station. At the same time, the demolition of the existing walls is arranged after the roof slab is sealed, so that the demolition work is completed within the sealed space. This avoids the risk of water intrusion and enables subsequent structural connections between the new and existing station roof slabs. Thus, without reserving post-cast strips, the demolition of existing walls and the effective connection between the old and new station roof slabs can be safely completed, fundamentally solving the technical problem of water intrusion affecting the operational safety of existing railway lines.
[0008] In some embodiments, prior to implementing step one, barriers and temporary water barriers are constructed at the concourse level or transfer node interface location on the side of the existing station. Because these barriers and temporary water barriers are constructed at the concourse level or transfer node interface location on the side of the existing station before implementing step one, even in the early stages of construction before the roof of the new station is sealed, the barriers and water barriers can provide physical isolation in the event of accidental water intrusion (such as pipeline bursts or temporary water accumulation), preventing water from flowing into the existing station's operating area. This provides double safety assurance for the subsequent core process of sealing the roof before demolishing the walls, ensuring the absolute safety of the existing line's operation.
[0009] In some embodiments, prior to step one, the method further includes: after the excavation of the new station reaches the bottom, chiseling the upper end of the existing station's piles down to an elevation level flush with the bottom surface of the new station's central slab interface beam, while retaining the pile reinforcement; in subsequent construction, anchoring the retained pile reinforcement into the central slab interface beam of the new station, and casting it together with the central slab interface beam. Because the method of chiseling the upper end of the existing station's piles down to an elevation level flush with the bottom surface of the new station's central slab interface beam while retaining the pile reinforcement, and then anchoring the pile reinforcement into the central slab interface beam and casting it together in subsequent construction, allows the existing station's piles and the new station's central slab interface beam to form an integral load-bearing structure. This effectively compensates for the structure's buoyancy resistance and enhances the overall stability and structural safety of the transfer node interface, even without the need for post-cast strips and pre-sealing of the top slab.
[0010] In step one, the stirrups of the upper beam are thrown downwards to form reserved upper and lower beam stirrup ends; in step three, before pouring the lower beam, a cast corbel is first set at the interface between the upper beam and the lower beam, and then the reinforcing bars of the lower beam are installed and welded to the reserved upper and lower beam stirrup ends. The welding is a single-sided weld with a welding length of 10d, where d is the diameter of the reinforcing bar. The cast corbel is removed after the concrete of the lower beam reaches the design strength. By employing the method of extending the stirrups of the upper beam downwards in step one to reserve the stirrup extensions for the upper and lower beams, and by first setting up the cast-in-place corbel in step three, and then welding the lower beam reinforcement to the extended stirrup extensions on one side (weld length 10d), and then removing the corbel after the concrete has reached its strength, the upper and lower beams achieve a reliable load-bearing connection through steel reinforcement welding, ensuring the integrity of the structure after disassembly. At the same time, the setting of the cast-in-place corbel ensures the compactness and vibration quality of the concrete at the joint, further enhancing the waterproof performance and structural reliability of the joint.
[0011] In some embodiments, in step one, the lower opening of the top slab of the new station transfer node interface is cast at a 15° angle, with the angle sloping upwards from the side of the new station towards the side of the existing station. Because the lower opening of the top slab of the new station transfer node interface is cast at a 15° angle in step one, and the angle slopes upwards from the side of the new station towards the side of the existing station, the concrete can fill densely from bottom to top along the slope when the lower beam is subsequently poured. This effectively reduces cold joints and voids, thereby significantly improving the waterproofing performance at the joint between the upper and lower beams, preventing water from seeping in from the joint, and ensuring the waterproofing reliability of the transfer node interface.
[0012] This invention also provides a structural modification structure for the transfer interface between a new and existing station, comprising an upper beam and a lower beam. The upper beam is integrally cast with the roof slab of the new station and is located below and connected to the roof slab of the existing station. The lower beam is cast below the upper beam and fixedly connected to it. Together, the upper and lower beams form a C-shaped beam connecting the roof slabs of the new and existing stations. Because the upper beam is integrally cast with the roof slab and located below and connected to the roof slab of the existing station, and the lower beam is cast below and fixedly connected to the upper beam, the two together form a C-shaped beam structure. This allows for a reliable structural connection between the roof slabs of the new and existing stations without the need for pre-cast strips. Simultaneously, the integral casting of the upper beam with the roof slab allows for pre-sealing of the roof slab, preventing water intrusion from the structural design stage, ensuring structural safety and meeting waterproofing and flood prevention requirements.
[0013] In some embodiments, the lower opening of the upper beam is a 15° bevel, which slopes upwards from the side of the newly built station towards the side of the existing station. Because the upper beam has a 15° bevel at the bottom, and the bevel slopes upwards from the side of the newly built station towards the side of the existing station, a sloping structure is formed at the joint between the upper and lower beams, which facilitates concrete filling. Therefore, after the structure is formed, this bevel can guide possible seepage paths, enhance the self-waterproofing ability of the joint, and also provide a structural foundation for the dense pouring of the joint during construction.
[0014] In some embodiments, the internal reinforcement structure of the C-beam includes: C-beam main reinforcement arranged along the longitudinal length of the beam, C-beam structural reinforcement arranged on the side of the beam, C-beam upper and lower reinforcing stirrups densely arranged near the construction joint of the upper and lower L-beam interfaces, C-beam hook reinforcement connecting the C-beam main reinforcement and the C-beam structural reinforcement, C-beam anchoring reinforcement with one end anchored in the C-beam and the other end extending into the existing station roof slab and connected to the existing line roof slab reserved reinforcement connector, and new line roof slab main reinforcement provided in the new station roof slab and connected to the C-beam main reinforcement; the upper beam has reserved upper and lower beam stirrup outstretched ends that are thrown downwards, and the lower beam has reinforcement bars that are welded to the reserved upper and lower beam stirrup outstretched ends, the welding is a single-sided weld, the weld length is 10d, where d is the diameter of the reinforcement bar, and the welding point forms a C-beam upper and lower stirrup joint. By using C-shaped main reinforcement bars arranged along the entire length of the beam, C-shaped anchorage bars anchored to the existing station roof slab, and new main reinforcement bars for the new line roof slab located within the new station roof slab and connected to the main reinforcement bars, a complete force transmission path is formed between the split upper and lower beams, ensuring the structural integrity and load-bearing capacity of the connection node between the old and new station roof slabs. Simultaneously, by densely arranging upper and lower reinforcing stirrups of the C-shaped beams near the construction joint at the interface of the upper and lower beams, and by setting C-shaped hook reinforcement bars to connect the main reinforcement bars and structural reinforcement bars, the shear resistance and concrete strength of the joint area are effectively enhanced. The reinforcement effect prevents cracking at the joint due to stress or shrinkage. In addition, the reserved upper and lower beam stirrups of the upper beam are welded to the steel bars of the lower beam through single-sided welding (weld length 10d) to form C-shaped beam upper and lower stirrup joints, realizing a reliable connection of the beams after splitting, ensuring the continuous force transmission of the steel bars at the construction joint, and enabling the structural connection of the roof slabs of the new and old stations without reserving post-pouring strips. This ensures the stress reliability, crack resistance and durability of the transfer node interface, and solves the safety hazard of water intrusion into the existing operating station caused by the presence of post-pouring strips.
[0015] In some embodiments, the system also includes retained reinforcing bars from the existing station's piles. These retained reinforcing bars extend from below the bottom surface of the central slab interface beam of the new station into the interior of the central slab interface beam, are fixedly connected to the reinforcing cage of the central slab interface beam, and are integrally cast with the central slab interface beam. Because the existing station's pile reinforcing bars extend from below the bottom surface of the central slab interface beam of the new station into the interior of the central slab interface beam, are fixedly connected to the reinforcing cage of the central slab interface beam, and are integrally cast, the existing piles and the central slab interface beam of the new station form an integrated load-bearing system. This enhances the anti-buoyancy capacity and overall stability at the transfer node interface, effectively integrates the old and new structures, and demonstrates full utilization of the existing structure.
[0016] In some embodiments, the system also includes columns for the newly constructed station. The reinforcing bars of the columns are connected to the pre-reserved reinforcing bars below the upper beam via straight threaded sleeves, and the connection joint is located below the lower beam. The lower beam and the columns are integrally cast together. Because the reinforcing bars of the newly constructed station columns are connected to the pre-reserved reinforcing bars below the upper beam via straight threads, and the connection joint is located below the lower beam, and the lower beam and the columns are integrally cast together, a complete force transmission path is formed between the columns and the upper and lower beams. The location of the joint below the beam facilitates construction operations and avoids the core area of the node, thus meeting seismic design requirements. Simultaneously, the straight threaded connection ensures the reliability of the reinforcing bar connection and construction efficiency, further enhancing the integrity and safety of the transfer node interface structure.
[0017] Compared with the prior art, the present invention has the following advantages and beneficial effects:
[0018] 1. During the construction phase of the new station roof slab, the upper beam is constructed first and cast integrally with the roof slab to seal the roof slab. This ensures that the roof slab of the new station is sealed before the existing walls are demolished, thereby eliminating the need for the post-cast strip that must be reserved in the traditional process. This cuts off the path for surface water, rainwater, or leaks from damaged pipelines to enter the existing operating station from the source.
[0019] 2. After the excavation of the new station reaches the bottom, the upper end of the piles of the existing station is chiseled down to the elevation level of the bottom surface of the interface beam of the middle slab of the new station, while retaining the pile reinforcement. In subsequent construction, the pile reinforcement is anchored into the interface beam of the middle slab and cast together, so that the piles of the existing station and the interface beam of the middle slab of the new station form an integral load-bearing structure. This effectively compensates for the structure's anti-buoyancy capacity and enhances the overall stability and structural safety of the transfer node interface, even with the elimination of the post-cast strip and the pre-closure of the top slab.
[0020] 3. Throw the stirrups of the upper beam downwards at the stubble, and first set up the cast corbel in step 3. Then weld the lower beam reinforcement to the stubble of the thrown stirrups on one side (weld length 10d). After the concrete reaches the strength, remove the corbel so that the upper beam and the lower beam can achieve a reliable stress connection through steel reinforcement welding, ensuring the integrity of the structure after disassembly. Attached Figure Description
[0021] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:
[0022] Figure 1 This is a longitudinal cross-sectional schematic diagram of the interface structure between the newly built station and the existing station in this invention;
[0023] Figure 2 For the present invention Figure 1 Cross-sectional schematic diagrams of the middle C-shaped beam, the upper L-shaped beam, and the lower L-shaped beam;
[0024] Figure 3 This is a schematic diagram of the C-shaped beam reinforcement structure in this invention;
[0025] Figure 4 This is a schematic diagram of the upper L-shaped beam and top slab formwork support system in this invention;
[0026] Figure 5 This is a schematic diagram of the lower L-shaped beam formwork support system in this invention.
[0027] The attached diagram shows the markings and corresponding component names:
[0028] 1. Existing line top slab; 2. Existing line middle slab; 3. Existing line bottom slab; 4. Existing line side wall to be demolished; 5. C-shaped beam; 6. Upper L-beam 5a; 7. Upper L-beam 5b; 8. Column joint; 9. Column pre-reserved reinforcement bar extension; 10. Pre-reserved upper and lower beam stirrup extension; 11. Existing line top slab pre-reserved steel bar connector; 12. Post-cast corbel; 13. Middle slab interface beam; 14. New station top slab; 15. New station middle slab; 16. New station bottom slab; 17. Existing station piles; 18. Temporary water retaining wall; 19. Construction enclosure; 20. Existing line earthwork slope line on one side; 21. C-shaped beam main reinforcement; 22. C-shaped beam structural reinforcement; 33. C-shaped beam upper reinforcement. 22. Lower reinforcing stirrups; 23. C-shaped beam hook bars; 24. C-shaped beam anchor bars; 25. C-shaped beam upper and lower stirrup joints; 27. New line top slab main reinforcement; 26. Straight threaded sleeves; 28. Beam bottom formwork secondary ribs; 29. Beam bottom formwork main ribs; 30. Wooden diagonal reinforcement; 31. New line top slab formwork; 32. New line top slab formwork secondary ribs; 33. New line top slab formwork and beam disc buckle support system; 34. Lower beam side formwork; 35. Side formwork secondary ribs; 36. Side formwork main ribs; 37. Bottom formwork; 38. Bottom formwork secondary ribs; 39. Bottom formwork main ribs; 40. Tie rods; 42. C-shaped beam lower beam disc buckle support system. Detailed Implementation
[0029] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.
[0030] Throughout this specification, references to "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the invention. Therefore, the phrases "an embodiment," "an example," "an example," or "an example" appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. Moreover, those skilled in the art will understand that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0031] In the description of this invention, the terms "front", "rear", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.
[0032] The terms "first," "second," etc., used in this invention are merely for clarity of description and are not intended to limit any order or emphasize importance. Furthermore, the term "connection" as used herein, unless otherwise specified, can refer to a direct connection or an indirect connection via other components.
[0033] Example 1
[0034] like Figures 1-5 As shown, traditional open-cut station transfer node interface construction requires reserving a 3-5m wide post-cast strip on the roof slab of the new station for removing excavated soil after demolishing the existing side walls. During this period, the post-cast strip is exposed for a long time, and surface water can easily seep into the existing operating station during underground pipe network damage or the rainy season, causing serious safety hazards. Although the industry has tried measures such as temporary shielding and enhanced drainage, these are all passive protections and cannot completely solve the problem of water intrusion. Moreover, the presence of the post-cast strip delays the slab closure, and the construction period is greatly affected by the weather. Therefore, this embodiment 1 provides a construction method for the renovation of the transfer interface between a new station and an existing station, including the following steps:
[0035] Step 1: Before carrying out the construction of the main structure of the new station, first set up construction barriers 18 and temporary water barriers 17 on the concourse level or transfer node interface of the existing station to prevent accidental water from flowing into the existing line operation area during construction.
[0036] Step Two: After the excavation of the new station reaches the bottom, the upper end of the existing station pile 16 is chiseled down to an elevation level flush with the bottom surface of the central slab interface beam 12 of the new station, while retaining the pile reinforcement. During subsequent construction, this retained reinforcement will be anchored into the central slab interface beam 12. When chiseling the pile, the elevation error of the pile top should be controlled to ≤ ±5mm to ensure that the length of the retained reinforcement extending into the central slab interface beam meets the design requirements.
[0037] Step 3: Construct the new station base slab 15, side walls up to the bottom of the new station middle slab 14, and simultaneously install the reinforcing bars of the middle slab interface beam 12, the new station middle slab 14, and the lower reinforcing bars of the new station columns 6. Then pour concrete to form the lower part of the new station base slab 15, side walls, new station middle slab 14, middle slab interface beam 12, and columns 6.
[0038] Step 4: Excavate the earthwork at the existing station transfer node interface up to above the existing station roof slab 1, remove the waterproof protective layer of the existing station roof slab 1, peel off the waterproof layer and protect it properly. The earthwork excavation is carried out according to the slope requirements of the earthwork slope line 19 on one side of the existing line to ensure the stability of the soil on the side of the existing station during the excavation process and prevent landslides from affecting the operation of the existing line. The slope coefficient is determined according to the geological conditions and the depth of the foundation pit. In this embodiment, the slope is 1:1.5.
[0039] Step 5: Roughen the surface of the side wall 4 to be demolished, and chisel out the pre-reserved steel bar connector 10 on the existing roof slab.
[0040] Step Six: Install the reinforcing bars for the upper L-shaped beam 5a (i.e., the upper beam) and the reinforcing bars for the newly built station roof slab 13. This specifically includes:
[0041] The stirrups of the upper L-shaped beam 5a are thrown downward to form the reserved stirrup ends 9 of the upper and lower beams;
[0042] 8 column reinforcement bars are reserved with 8 column reinforcement bar extensions, and 26 straight threaded sleeves are installed at the joints;
[0043] Install the main reinforcement 20, structural reinforcement 21, upper and lower reinforcing stirrups 22, hook reinforcement 23, anchorage reinforcement 24, and main reinforcement 27 of the new line top slab.
[0044] 34. Erect the new line top slab formwork and beam buckle support system;
[0045] Install the bottom formwork of the upper part of the C-shaped beam, and set the secondary rib 28 and the main rib 29 of the bottom formwork;
[0046] Wooden diagonal reinforcement members 30 are installed at the sloping opening of the bottom formwork of the beam to support and fix the formwork shape of the 15° sloping opening 17;
[0047] Install the new line top plate template 31, and set the new line top plate template secondary ribs 32 and the new line top plate template main ribs 33.
[0048] After the formwork is installed, the upper L-shaped beam 5a is integrally cast with the new station roof slab 13, and the lower edge of the roof slab is cast into a 15° sloping opening 17, which slopes upwards from the new station side towards the existing station side. At this point, the new station roof slab 13 is sealed, eliminating the need for a post-cast strip. The 15° sloping angle is not arbitrarily chosen; field tests have verified that when the angle is less than 10°, air bubbles are difficult to expel during concrete casting, easily leading to honeycomb-like pitting; when the angle is greater than 20°, the slope is too steep, causing concrete to slip easily, and the waterproofing effect at the joints decreases. The 15° sloping angle maximizes the self-waterproofing capacity at the joints while ensuring the density of the concrete casting.
[0049] Step 7: After the roof slab is sealed, demolish the side wall 4 to be demolished at the existing station transfer node interface. Since the roof slab is sealed, the demolition work is carried out in a safe environment, and water cannot enter.
[0050] Step 8: Install the formwork for the post-cast corbel 11 at the interface between the upper and lower beams. Then install the formwork support system for the lower L-shaped beam 5b (i.e., the lower beam body):
[0051] 42. Erect a C-shaped beam lower beam buckle support system;
[0052] Install the bottom formwork 38 of the lower beam, and set the secondary ribs 39 and the main ribs 40 of the bottom formwork;
[0053] Install the lower beam side formwork 35, and set the secondary side formwork ribs 36 and the main side formwork ribs 37;
[0054] Tie rods 41 are installed between the two side templates to resist the lateral pressure of the concrete.
[0055] Install the reinforcing bars of the lower L-shaped beam 5b and the remaining reinforcing bars of the newly built vehicle support column 6. Weld the reinforcing bars of the lower L-shaped beam 5b to the reserved upper and lower beam stirrup extensions 9 of the upper L-shaped beam 5a to form a C-shaped beam upper and lower stirrup joint 25, using single-sided welding with a welding length of 10d. Connect the reinforcing bars of column 6 to the reserved column reinforcement extensions 8 through a straight threaded sleeve 26.
[0056] Next, the concrete for the lower L-shaped beam 5b and the newly built vehicle support column 6 is poured, so that the lower L-shaped beam 5b and the column 6 are integrally formed. After the concrete reaches the design strength, the post-cast corbel 11 is removed. The single-sided weld length of 10d (d is the diameter of the reinforcing bar) is determined according to the requirements for the lap length of reinforcing bars in the "Code for Design of Concrete Structures" (GB50010) and in combination with the on-site pull-out test, which can ensure that the connection strength is not lower than that of the parent material and facilitate on-site construction operations.
[0057] Step 9: The upper L-shaped beam 5a and the lower L-shaped beam 5b form a complete C-shaped beam 5, realizing an effective connection between the new station roof slab 13 and the existing station roof slab 1.
[0058] By splitting the C-shaped beam 5 at the transfer node interface into an upper L-shaped beam 5a and a lower L-shaped beam 5b, and adopting the process of first sealing the top, then demolishing the walls, and then pouring the lower part, the post-pouring strip was eliminated, avoiding the risk of water intrusion into the existing station. At the same time, through structural measures such as spliced welding, 15° bevel, anchoring the pile reinforcement into the middle plate interface beam, and straight thread connection of column reinforcement, as well as the refined reinforcement design of the main reinforcement, structural reinforcement, reinforcing stirrups, hook reinforcement, and anchoring reinforcement of the C-shaped beam, the integrity, buoyancy resistance, and waterproof performance of the structure are ensured, significantly improving construction safety and schedule controllability.
[0059] Example 2
[0060] See Figures 1-5This embodiment 2 provides a modification structure for the transfer interface between a new station and an existing station, including an upper beam (upper L-beam 5a) and a lower beam (upper L-beam 5b). The upper beam is integrally cast with the roof slab 13 of the new station and is located below the side of the roof slab 1 of the existing station and connected to the roof slab 1 of the existing station. The lower beam is cast below the upper beam and is fixedly connected to the upper beam. The upper beam and the lower beam together constitute a C-shaped beam connecting the roof slab of the new station and the roof slab of the existing station. Because the upper beam is cast integrally with the new station roof slab 13 and is located below and connected to the existing station roof slab 1, and the lower beam is cast below the upper beam and fixedly connected to it, the two together form a C-shaped beam structure, which enables a reliable structural connection between the new station roof slab 13 and the existing station roof slab 1 without the need to reserve a post-cast strip; at the same time, the integral casting of the upper beam with the roof slab enables the roof slab to be sealed in advance, eliminating the path of water intrusion from the source of structural design, which not only ensures structural safety, but also meets the requirements of waterproofing and flood prevention.
[0061] See Figure 1 and Figure 3 The lower opening of the upper beam is a 15° bevel, sloping upwards from the side of the newly built station towards the side of the existing station. This 15° bevel at the bottom of the upper beam, sloping upwards from the side of the newly built station towards the side of the existing station, creates a sloping surface at the joint between the upper and lower beams that facilitates concrete filling. After the structure is formed, this bevel can guide potential water seepage paths, enhance the self-waterproofing ability of the joint, and also provide a structural foundation for the dense pouring of the joint during construction.
[0062] See Figures 1-3The internal reinforcement structure of the C-shaped beam includes: C-shaped beam main reinforcement 20 arranged along the longitudinal length of the beam; C-shaped beam structural reinforcement 21 arranged on the side of the beam; C-shaped beam upper and lower reinforcing stirrups 22 densely arranged near the construction joint 7 of the upper and lower L-shaped beam interface; C-shaped beam hook reinforcement 23 connecting the C-shaped beam main reinforcement 20 and the C-shaped beam structural reinforcement 21; C-shaped beam anchoring reinforcement 24 with one end anchored in the C-shaped beam and the other end extending into the existing station roof slab and connected to the existing line roof slab reserved reinforcement connector 10; and new line roof slab main reinforcement 27 located in the new station roof slab and connected to the C-shaped beam main reinforcement 20; the upper beam has reserved upper and lower beam stirrup extensions 9 extending downwards; the lower beam has reinforcement bars welded to the reserved upper and lower beam stirrup extensions 9; the welding is a single-sided welding with a weld length of 10d, where d is the diameter of the reinforcement bar; and the welding point forms a C-shaped beam upper and lower stirrup joint 25. By using C-shaped main reinforcement 20 arranged along the entire length of the beam, C-shaped anchor reinforcement 24 anchored to the existing station roof slab, and new line roof slab main reinforcement 27 located within the new station roof slab and connected to the main reinforcement, the split upper and lower beams form a complete force transmission path, ensuring the structural integrity and load-bearing capacity of the connection node between the old and new station roof slabs. Simultaneously, by densely arranging C-shaped upper and lower reinforcing stirrups 22 near the construction joint 7 at the interface of the upper and lower beams, and setting C-shaped hook reinforcement 23 to connect the main reinforcement and structural reinforcement, the shear resistance of the joint area is effectively enhanced. The concrete provides confinement, preventing cracking at the joints due to stress or shrinkage. Furthermore, the pre-reserved upper and lower beam stirrup extensions 9 of the upper beam are welded to the lower beam's reinforcing bars on one side (weld length 10d) to form C-shaped beam stirrup joints 25. This ensures a reliable connection between the split beams, guaranteeing continuous force transmission at the construction joints. This allows for structural connection between the new and old station roof slabs without the need for post-cast strips, ensuring the reliability, crack resistance, and durability of the transfer node interface, and resolving the safety hazard of water intrusion into existing operating stations caused by the presence of post-cast strips.
[0063] See Figure 1 and Figure 2 It also includes the retained reinforcing bars of the existing station piles 16. These retained reinforcing bars extend from below the bottom surface of the central slab interface beam 12 of the new station into the interior of the beam, and are fixedly connected to the reinforcing cage of the beam 12, and are integrally cast together with the beam 12. Because the existing station pile reinforcing bars extend from below the bottom surface of the central slab interface beam 12 of the new station into the interior of the beam 12, and are fixedly connected to the reinforcing cage of the beam 12 and integrally cast, the existing piles 16 and the central slab interface beam 12 of the new station form an integrated load-bearing system. This enhances the anti-buoyancy capacity and overall stability at the transfer node interface, and effectively integrates the old and new structures, demonstrating full utilization of the existing structure.
[0064] See Figures 1-5It also includes the columns 6 of the newly built station. The steel bars of the columns 6 are connected to the column pre-reserved steel bar ends 8 below the upper L-shaped beam 5a through straight threaded sleeves 26, and the connection joint is located below the lower L-shaped beam 5b. The lower L-shaped beam 5b and the columns 6 are integrally cast. Because the steel bars of the columns 6 of the newly built station are connected to the pre-reserved steel bars below the upper L-shaped beam 5a through straight threaded sleeves 26, and the connection joint is located below the lower L-shaped beam 5b, and the lower L-shaped beam 5b and the columns 6 are integrally cast, the columns 6, the upper L-shaped beam 5a and the lower L-shaped beam 5b form a complete force transmission path. The joint position is set below the beam, which is conducive to construction operation and avoids the core area of the node, so as to meet the seismic design requirements. At the same time, the straight threaded connection ensures the reliability of the steel bar connection and construction efficiency, further enhancing the integrity and safety of the transfer node interface structure.
[0065] This invention is not only applicable to the renovation of transfer nodes between newly built subway stations and existing operating stations through open-cut excavation, but can also be extended to the construction of new and old structure connections in other underground projects, such as underground integrated pipe corridors, underground commercial streets, and civil defense projects, which require structural connections without interrupting operations. It has a wide range of applicability.
[0066] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A construction method for renovating the transfer interface between a newly built station and an existing station, characterized in that, Includes the following steps: Step 1: During the construction phase of the new station roof slab, first construct the upper beam at the interchange node interface, and then cast the upper beam integrally with the new station roof slab to seal the new station roof slab. Step 2: After the roof slab is sealed, remove the existing wall structure at the transfer node interface of the station. Step 3: After the wall is demolished, construct the lower beam at the transfer node interface and fix the lower beam to the upper beam to form a complete transfer node interface beam structure, thus realizing the structural connection between the roof of the new station and the roof of the existing station.
2. The construction method for renovating the transfer interface between a new station and an existing station according to claim 1, characterized in that, Before implementing step one, construct barriers and temporary water barriers at the concourse level or transfer node interface location on one side of the existing station.
3. The construction method for renovating the transfer interface between a newly built station and an existing station according to claim 1, characterized in that, Before step one, the process also includes: after the excavation of the new station reaches the bottom, the upper end of the piles of the existing station is chiseled down to an elevation level that is flush with the bottom surface of the interface beam of the middle plate of the new station, while retaining the pile reinforcement; in subsequent construction, the retained pile reinforcement is anchored into the interface beam of the middle plate of the new station and cast together with the interface beam.
4. The construction method for renovating the transfer interface between a newly built station and an existing station according to claim 1, characterized in that, In step one, the stirrups of the upper beam are thrown downwards to form reserved upper and lower beam stirrup ends; in step three, before pouring the lower beam, a cast corbel is first set at the interface between the upper beam and the lower beam, and then the reinforcing bars of the lower beam are installed and welded to the reserved upper and lower beam stirrup ends. The welding is a single-sided weld with a welding length of 10d, where d is the diameter of the reinforcing bar. The cast corbel is removed after the concrete of the lower beam reaches the design strength.
5. The construction method for renovating the transfer interface between a newly built station and an existing station according to claim 1, characterized in that, In step one, the lower opening of the top plate of the transfer node interface of the new station is cast into a 15° sloping opening, which slopes upward from the side of the new station towards the side of the existing station.
6. A structure for modifying the transfer interface between a newly built station and an existing station, characterized in that, include: The upper beam is cast integrally with the roof slab of the new station and is located on the side below the roof slab of the existing station and connected to the roof slab of the existing station. The lower beam is cast below the upper beam and fixedly connected to the upper beam. The upper beam and the lower beam together form a C-shaped beam connecting the roof of the new station and the roof of the existing station.
7. The structure for modifying the transfer interface between a newly built station and an existing station according to claim 6, characterized in that, The lower opening of the upper beam is a 15° sloping opening, which slopes upward from the side of the newly built station toward the side of the existing station.
8. The structure for modifying the transfer interface between a newly built station and an existing station according to claim 6, characterized in that, The internal reinforcement structure of the C-shaped beam includes: C-shaped beam main reinforcement arranged along the longitudinal length of the beam; C-shaped beam structural reinforcement arranged on the side of the beam; C-shaped beam upper and lower reinforcing stirrups densely arranged near the construction joint of the upper and lower L-shaped beams; C-shaped beam hook reinforcement connecting the C-shaped beam main reinforcement and the C-shaped beam structural reinforcement; C-shaped beam anchoring reinforcement with one end anchored in the C-shaped beam and the other end extending into the existing station roof slab and connected to the existing line roof slab reserved reinforcement connector; and new line roof slab main reinforcement located in the roof slab of the new station and connected to the C-shaped beam main reinforcement. The upper beam has reserved upper and lower beam stirrup extensions that extend downwards, and the lower beam has reinforcements welded to the reserved upper and lower beam stirrup extensions. The welding is a single-sided weld with a weld length of 10d, where d is the diameter of the reinforcement. The weld point forms a C-shaped beam upper and lower stirrup joint.
9. The structure for modifying the transfer interface between a newly built station and an existing station according to claim 6, characterized in that, It also includes the retained reinforcing bars of the existing station piles. The retained reinforcing bars extend from below the bottom surface of the middle plate interface beam of the new station into the interior of the middle plate interface beam and are fixedly connected to the reinforcing cage of the middle plate interface beam, and are integrally cast with the middle plate interface beam.
10. The structure for modifying the transfer interface between a newly built station and an existing station according to claim 6, characterized in that, It also includes the columns of the newly built station, wherein the steel bars of the columns are connected to the column pre-reserved steel bar ends below the upper beam through straight threaded sleeves, and the connection joint is located below the lower beam. The lower beam and the columns are integrally cast together.