Building pipeline transition waterproofing structure
By installing pipe shafts, waterproof eaves, and other components in existing buildings, the problem of rainwater leakage when mechanical and electrical equipment pipelines cross expansion joints is solved, achieving active shielding and centralized storage protection, and improving the waterproof performance of buildings and pipeline safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- GUANGZHOU DESIGN INST
- Filing Date
- 2025-07-18
- Publication Date
- 2026-07-31
AI Technical Summary
In the renovation of existing buildings, when the pipelines of mechanical and electrical equipment cross the expansion joints, rainwater can easily seep into the building through the outer wall of the pipelines, leading to structural erosion and safety threats.
Design an existing building pipeline transition waterproof and drainage structure, including components such as pipe wells, waterproof eaves, waterstops, foam filling boards and drainage channels. By setting waterproof eaves on the curtain wall to cover the expansion joints, setting cable passage cavities and water-blocking parts in the pipe wells, and combining drainage ditches and drying parts, active shielding and centralized storage protection are formed.
It effectively shields rainwater from the source, proactively protects pipelines, ensures orderly pipeline transitions and isolation from the external environment, reduces the risk of leakage, and improves the waterproofing performance and pipeline safety inside the building.
Smart Images
Figure CN120683944B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of building engineering technology, and in particular to a waterproof and drainage structure for transitioning existing building pipelines. Background Technology
[0002] When existing buildings are renovated or expanded, they are usually composed of multiple building units, such as a taller building tower (the first building unit) and a lower building podium (the second building unit), which are multiple independent structural units. In order to accommodate uneven settlement, thermal expansion and contraction, and seismic activity that may occur between different structural units, structural expansion joints must be set between them.
[0003] In renovation projects, a large number of mechanical and electrical equipment (such as air conditioning units and ventilation equipment) are often installed on the lower roof of the podium, while serving the higher building tower. This inevitably leads to a large number of mechanical and electrical pipelines (such as refrigerant pipes, water pipes, and cables) needing to originate from the podium roof, cross and traverse the expansion joint between the tower and the podium, and ultimately penetrate the tower's curtain wall to enter its interior. When these pipelines cross the expansion joint, the pipelines themselves become direct channels for rainwater to infiltrate the building's interior.
[0004] Specifically, when rainwater flows through the tower's curtain wall facade or lands in expansion joint areas, it easily flows along the outer walls of the pipes. Because the bonding interface between the pipes and the waterproofing layer or the first sealant is extremely small, and is constantly affected by temperature changes (the pipes' own thermal expansion and contraction), vibration, and building displacement, traditional sealing measures (such as applying the first sealant) are prone to cracking, aging, or detachment, creating leakage pathways. Once the seal fails, rainwater can flow unimpeded along the outer walls of the pipes, through the curtain wall, and into the building's interior. This leakage not only corrodes the building structure but also poses a serious threat to the safe operation of the pipes themselves. Summary of the Invention
[0005] The purpose of this invention is to provide a waterproof and drainage structure for the transition of pipelines in existing buildings, which aims to solve the problem in the prior art that when pipelines of electromechanical equipment cross deformation joints, rainwater can easily seep into the interior of the building along the outer wall of the pipelines.
[0006] To achieve the above objectives, the present invention provides a drainage and waterproofing structure for pipeline transition in existing buildings. The existing building includes a first building unit and a second building unit spaced apart horizontally. A curtain wall is provided on the end face of the first building unit near the second building unit. Mechanical and electrical equipment is installed on the top surface of the second building unit. The pipelines of the mechanical and electrical equipment pass through the curtain wall and enter the interior of the first building unit. The drainage and waterproofing structure for pipeline transition in existing buildings includes:
[0007] The manhole is located on the top surface of the second building unit and between the electromechanical equipment and the curtain wall. There is an expansion joint between the manhole and the curtain wall. The manhole has a cable passage cavity inside and a cable passage opening connected to the cable passage cavity is provided on the manhole. The pipeline of the electromechanical equipment passes through the cable passage opening and the cable passage cavity in sequence, passes through the top surface of the second building unit, passes through the expansion joint, passes through the curtain wall and enters the interior of the first building unit. The cable passage opening is provided with a water-blocking part to prevent rainwater from entering the cable passage cavity.
[0008] A waterproof eaves is installed on the curtain wall, and when viewed vertically, the waterproof eaves can cover the expansion joint.
[0009] Furthermore, a drainage ditch is provided between the electromechanical equipment and the manhole, the top surface of the waterproof eaves has a first drainage slope toward the manhole, and the manhole has a second drainage slope toward the drainage ditch.
[0010] Furthermore, the existing building pipeline transition drainage structure also includes a waterstop, and a first sealant is connected between the top surface of the pipe well and the bottom surface of the waterproof eaves. One end of the waterstop is set on the waterproof eaves, and the other end of the waterstop is attached to the upper end of the pipe well through the first sealant.
[0011] Furthermore, the existing building pipeline transition drainage structure also includes a foam filling board, which is installed in the expansion joint, and the two sides of the foam filling board are respectively connected to the curtain wall and the pipe shaft.
[0012] Furthermore, a fire-resistant strip is provided at the lower end of the foam-filled board.
[0013] Furthermore, a drainage channel is provided between the curtain wall and the second building unit, and the drainage channel is located below the fire-resistant strip.
[0014] Furthermore, the drainage channel has a third drainage slope.
[0015] Furthermore, the water-blocking part includes a rainproof louver disposed at the cable passage.
[0016] Furthermore, a drying section is provided on the wire passage, and the drying section is located inside the water-blocking section.
[0017] Furthermore, the drying section includes a drying fan.
[0018] Compared with existing technologies, the beneficial effects of the existing building pipeline transition waterproofing and drainage structure of this invention are as follows:
[0019] 1. Achieves source shielding and active protection: By installing waterproof eaves on the curtain wall that can cover the expansion joints, rainwater flowing down or falling directly along the curtain wall facade can be intercepted at the source, preventing it from directly washing away and intruding into the expansion joints and pipelines passing through the area, thus transforming the traditional passive sealing into active shielding and protection.
[0020] 2. Provides centralized storage and orderly transition: By setting up pipe wells, a centralized and protected internal passage cavity is provided for multiple pipelines that need to cross expansion joints. This not only makes the originally messy pipeline layout neat and orderly, but more importantly, it isolates the pipelines from the harsh external environment. The water-blocking part set at the passage opening further prevents rainwater from entering the passage cavity, providing a second layer of protection for the pipelines. Attached Figure Description
[0021] Figure 1 This is a schematic diagram of the existing building pipeline transition drainage structure according to an embodiment of the present invention;
[0022] Figure 2 This is a schematic diagram of the waterproof eaves of the existing building pipeline transition and drainage structure according to an embodiment of the present invention;
[0023] In the diagram, 1 represents the first building unit;
[0024] 2. Second building unit;
[0025] 3. Curtain wall
[0026] 4. Mechanical and electrical equipment;
[0027] 5. Well; 51. Cable passage cavity; 52. Cable passage opening;
[0028] 6. Water-blocking section; 61. Rainproof louvers;
[0029] 7. Waterproof eaves; 71. First eaves; 72. Second eaves;
[0030] 73. Connecting part; 731. First angle steel; 732. Steel beam;
[0031] 74. Support section; 741. First square tube; 742. Second square tube;
[0032] 75. Receiving cavity;
[0033] 76. Second angle steel;
[0034] 77. Second sealant;
[0035] 78. Third angle steel;
[0036] 79. Third sealant;
[0037] 7a. U-shaped channel steel;
[0038] 7b. Fourth sealant;
[0039] 8. Drainage ditch;
[0040] 9. Expansion joints;
[0041] 10. Waterstop strip;
[0042] 11. First sealant;
[0043] 12. Foam-filled board;
[0044] 13. Flame arrestor strip;
[0045] 14. Drainage trough;
[0046] 15. Drying section; 151. Drying fan;
[0047] X, the first direction; Y, the second direction. Detailed Implementation
[0048] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.
[0049] In the description of this invention, the terms "upper," "lower," "left," "right," "front," "rear," "inner," "outer," "lateral," and "longitudinal," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description. They are not intended to limit the indicated devices, elements, or components to having a specific orientation, or to be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention. Those skilled in the art can understand the specific meaning of these terms in this invention according to the specific circumstances.
[0050] In the description of this invention, the terms "provided with," "set up," "connected," and "placed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, elements, or components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0051] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, elements, or components (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.
[0052] The technical solution of the present invention will be further described below with reference to the embodiments and accompanying drawings.
[0053] like Figure 1-2 As shown in the figure, an embodiment of the present invention provides a waterproofing and drainage structure for the transition of pipelines in an existing building. The existing building includes a first building unit 1 and a second building unit 2 spaced apart in a horizontal direction. A curtain wall 3 is provided on the end face of the first building unit 1 near the second building unit 2. Mechanical and electrical equipment 4 is installed on the top surface of the second building unit 2. The pipelines of the mechanical and electrical equipment 4 pass through the curtain wall 3 and enter the interior of the first building unit 1. The waterproofing and drainage structure for the transition of pipelines in the existing building includes:
[0054] The manhole 5 is located on the top surface of the second building unit 2. The manhole 5 is located between the electromechanical equipment 4 and the curtain wall 3. There is an expansion joint 9 between the manhole 5 and the curtain wall 3. The manhole 5 has a cable passage cavity 51 inside. The manhole 5 has a cable passage opening 52 that is connected to the cable passage cavity 51. The pipeline of the electromechanical equipment 4 passes through the cable passage opening 52 and the cable passage cavity 51 in sequence, passes through the top surface of the second building unit 2, passes through the expansion joint 9, passes through the curtain wall 3 and enters the interior of the first building unit 1. The cable passage opening 52 is provided with a water-blocking part 6 to prevent rainwater from entering the cable passage cavity 51.
[0055] Waterproof eaves 7 are installed on the curtain wall 3. When viewed vertically, waterproof eaves 7 can cover the expansion joint 9.
[0056] Based on the above technical solution, by setting a waterproof eaves 7 on the curtain wall 3 that can cover the expansion joint 9, rainwater flowing down or falling directly along the facade of the curtain wall 3 can be intercepted at the source, preventing it from directly washing away and intruding into the expansion joint 9 and the pipelines passing through the area, thus transforming the traditional passive sealing into active shielding and protection; by setting a pipe well 5, a centralized and protected internal passage cavity 51 is provided for multiple pipelines that need to cross the expansion joint 9, which not only makes the originally messy pipeline layout more orderly, but more importantly, isolates the pipelines from the harsh external environment. The water-blocking part 6 set at the passage opening 52 further prevents ground rainwater from entering the passage cavity 51, providing a second layer of protection for the pipelines.
[0057] Preferably, a drainage ditch 8 is provided between the electromechanical equipment 4 and the manhole 5, the top surface of the waterproof eaves 7 has a first drainage slope toward the manhole 5, and the manhole 5 has a second drainage slope toward the drainage ditch 8.
[0058] The first drainage slope extends from the waterproof eaves 7 to the top surface of the manhole 5, ensuring that rainwater flowing down from the facade of the curtain wall 3 or falling directly onto the waterproof eaves 7 is actively and directionally guided to the top surface of the manhole 5. The second drainage slope extends from the top surface of the manhole 5 to the drainage ditch 8, ensuring that rainwater received from the waterproof eaves 7 and rainwater falling directly onto the manhole 5 is quickly and secondary guided to the drainage ditch 8. The synergistic effect of the two slopes avoids the possibility of water accumulation on the top surfaces of the two waterproof components, the waterproof eaves 7 and the manhole 5. Through rapid drainage, the hydrostatic pressure is greatly reduced, thereby significantly reducing the risk of leakage.
[0059] Preferably, the existing building pipeline transition drainage structure also includes a waterstop 10, and a first sealant 11 is connected between the top surface of the pipe well 5 and the bottom surface of the waterproof eaves 7. One end of the waterstop 10 is set on the waterproof eaves 7, and the other end of the waterstop 10 is attached to the upper end of the pipe well 5 through the first sealant 11.
[0060] The first sealant 11 is filled between the top surface of the manhole 5 and the waterproof eaves 7, forming a continuous and dense surface waterproof layer that can prevent water vapor from entering the expansion joint 9. This is the first line of defense. The waterstop 10, as a wider and more reliable physical barrier, is set at both ends on the waterproof eaves 7 and at the connection between the first sealant 11 and the upper surface of the manhole 5. This is the second line of defense. Even if the first sealant 11 is partially damaged due to aging, extreme displacement between the first building unit 1 and the second building unit 2, or construction defects after long-term use, any water flow that attempts to seep in will be intercepted by the waterstop 10, provided that the first sealant 11 still has some adhesive ability.
[0061] In another embodiment, the waterproof eaves 7 can be detachably installed on the curtain wall 3.
[0062] Specifically, the waterproof eaves 7 includes a first eave body 71, a second eave body 72, two connecting parts 73, and a supporting part 74. The two connecting parts 73 are respectively located at both ends of the curtain wall 3 in the first direction X. The two ends of the supporting part 74 in the first direction X are respectively connected to the two connecting parts 73. The first eave body 71 and the second eave body 72 are detachably installed on the supporting part 74. The first eave body 71, the second eave body 72, and the facade of the curtain wall 3 together form a receiving cavity 75 for accommodating the supporting part 74.
[0063] More specifically, the connecting part 73 includes a first angle steel 731 and a steel beam 732. One side wall of the first angle steel 731 is bolted to the end of the curtain wall 3 in the first direction X. The steel beam 732 is welded to the other end face of the first angle steel 731. The steel beam 732 extends toward the second building unit 2. The supporting part 74 includes a first square tube 741 and a second room tube. The first square tube 741 and the second square tube 742 are arranged at intervals along the second direction Y. Both the first square tube 741 and the second square tube 742 are... Extending along the first direction X, the first square tube 741 is set close to the curtain wall 3. The two ends of the first square tube 741 and the second square tube 742 are respectively welded to the steel beams 732 of the two connecting parts 73. The first square tube 741 and the second square tube 742 are both accommodated in the receiving cavity 75. When viewed along the first direction X, the first eaves 71 is L-shaped. The second eaves 72 is installed below the support part 74. The first eaves 71 covers the upper surface of the support part 74 and the end face of the support part 74 in the second direction Y.
[0064] The end face of the first eaves 71 near the curtain wall 3 is connected to the first square tube 741 by a second angle steel 76 and bolts. The end face of the first eaves 71 near the curtain wall 3 is filled with a second sealant 77, which covers the head of the bolt of the second angle steel 76. The end face of the second eaves 72 near the curtain wall 3 is connected to the first square tube 741 by a third angle steel 78 and bolts. The end face of the second eaves 72 near the curtain wall 3 is filled with a third sealant 79, which covers the head of the bolt of the third angle steel 78.
[0065] The end face of the second eaves 72 away from the curtain wall 3 and the other end of the L-shaped first eaves 71 are respectively connected to the two side walls of the U-shaped channel steel 7a by bolts. The bottom wall of the U-shaped channel steel 7a is connected to the second square tube 742 by bolts. The fourth sealant 7b is filled between the end face of the second eaves 72 away from the curtain wall 3 and the other end of the L-shaped first eaves 71.
[0066] In this context, the first direction X and the second direction Y are perpendicular to each other.
[0067] The connecting part 73 (including the first angle steel 731 and the steel beam 732) and the supporting part 74 (including the first square tube 741 and the second square tube 742) constitute a stable load-bearing frame. The first eaves 71 and the second eaves 72 serve as outer covering panels and are detachably installed on the load-bearing frame through connectors such as the second angle steel 76, the third angle steel 78, the U-shaped channel steel 7a, and bolts. When the first eaves 71 or the second eaves 72 is damaged, no destructive work is required on the load-bearing frame. The outer panel can be replaced independently simply by disassembling the corresponding fasteners and connectors, simplifying the maintenance process and effectively reducing maintenance costs. The waterproof function between the waterproof eaves 7 and the curtain wall 3 is provided by the second sealant 77 and the third sealant 79. When these sealants reach the end of their service life and need to be replaced, the first eaves 71 and the second eaves 72 can be temporarily disassembled. This exposes the connection between the eaves and the curtain wall 3, providing unobstructed working conditions for thoroughly removing the aged sealant. The reversible disassembly and assembly process ensures the quality of maintenance and avoids waterproofing hazards caused by inconvenient maintenance, thereby effectively extending the service life of the waterproof eaves 7.
[0068] Preferably, the existing building pipeline transition drainage structure also includes a foam filling board 12, which is installed in the expansion joint 9, and the two sides of the foam filling board 12 are respectively connected to the curtain wall 3 and the pipe well 5.
[0069] More preferably, a fire-resistant strip 13 is provided at the lower end of the foam-filled board 12.
[0070] The foam filling board 12 serves as the direct carrier of the fire-resistant strip 13. The fire-resistant strip 13 can be fixed flat and continuously on the surface of the foam filling board 12, ensuring that the fire-resistant strip 13 can be heated evenly and reliably expanded when a fire occurs, thereby tightly sealing the gaps caused by structural deformation or material combustion, and effectively preventing the spread of flames and high-temperature smoke.
[0071] More preferably, a drainage channel 14 is provided between the curtain wall 3 and the second building unit 2, and the drainage channel 14 is located below the fire barrier 13.
[0072] The drainage channel 14 is located below all the upper waterproof structures (waterproof eaves 7, first sealant 11, waterstop 10). Its function is to intercept and collect any trace leakage water that may have seeped through the upper waterproof structure due to material aging, extreme weather or construction defects, eliminate potential leakage risks, and thus improve the long-term reliability and ultimate tolerance of the entire waterproof structure.
[0073] It effectively isolates and protects the fire-stopping system, ensuring its long-term performance stability. The fire resistance performance of the fire-stopping strip 13 has high requirements for the dryness of its working environment. Placing the drainage channel 14 below the fire-stopping strip 13 can block trace amounts of moisture from below, preventing the fire-stopping strip 13 from wetting or remaining wet for a long time. This comprehensive physical isolation and protection of the fire-stopping strip 13 effectively prevents the performance degradation of the fire-resistant material due to moisture (such as expansion failure or material degradation). This ensures that even if the drainage channel 14 is burned out during a fire, the fire-stopping strip 13 can still perform its pre-set sealing function, solving the technical hidden danger of fire-resistant structure failure due to moisture erosion.
[0074] More preferably, the drainage channel 14 has a third drainage slope.
[0075] Specifically, the third drainage slope is 1%-2%.
[0076] Preferably, the water-blocking part 6 includes a rainproof louver 61 disposed at the cable passage 52.
[0077] The rainproof louver 61 has an inclined blade structure. Raindrops captured by the blades are guided to the outside of the louver along its inclined direction and discharged into the drainage ditch 8, thus reliably preventing rainwater from directly splashing into or entering the wiring cavity 51 of the manhole 5. The rainproof louver 61 constitutes an active defense barrier, solving the problem of rainwater directly intruding into the manhole 5 under severe weather conditions from the source. It provides direct waterproof protection for the pipelines entering the wiring cavity 51. Moreover, the rainproof louver 61 can effectively prevent larger foreign objects, such as leaves, garbage, birds or small animals, from entering the wiring cavity 51, avoiding damage to the pipelines or causing dangers such as short circuits.
[0078] Preferably, the wire passage 52 is further provided with a drying section 15, which is located inside the water-blocking section 6.
[0079] More preferably, the drying section 15 includes a drying fan.
[0080] The drying section 15 is located inside the water-blocking section 6 and can handle any trace amounts of water mist, moisture, or splashing water droplets that may penetrate the water-blocking section 6. Based on the passive water-blocking mechanism, an active environmental control measure is added, thereby providing a more reliable drying environment for the wire-passing cavity 51 and effectively preventing various malfunction risks caused by moisture.
[0081] In summary, this invention provides a waterproofing structure for transitioning existing building pipelines, achieving source shielding and active protection: by setting a waterproof eaves 7 on the curtain wall 3 to cover the expansion joint 9, rainwater flowing down or falling directly along the facade of the curtain wall 3 can be intercepted at the source, preventing it from directly scouring and intruding into the expansion joint 9 and the pipelines crossing the area, transforming the traditional passive sealing into active shielding protection; it also provides centralized storage and orderly transition: by setting a pipe well 5, a centralized and protected internal passage cavity 51 is provided for multiple pipelines that need to cross the expansion joint 9. This not only makes the originally messy pipeline layout neat and orderly, but more importantly, it isolates the pipelines from the harsh external environment. The water-blocking part 6 set at the passage opening 52 further prevents ground rainwater from entering the passage cavity 51, providing a second layer of protection for the pipelines.
[0082] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.
Claims
1. A drainage and waterproofing structure for pipeline transition in an existing building, wherein the existing building comprises a first building unit (1) and a second building unit (2) spaced apart in a horizontal direction, a curtain wall (3) is provided on the end face of the first building unit (1) near the second building unit (2), and electromechanical equipment (4) is installed on the top surface of the second building unit (2), wherein the pipelines of the electromechanical equipment (4) pass through the curtain wall (3) and enter the interior of the first building unit (1), characterized in that, include: The manhole (5) is located on the top surface of the second building unit (2). The manhole (5) is located between the electromechanical equipment (4) and the curtain wall (3). There is a deformation joint (9) between the manhole (5) and the curtain wall (3). The manhole (5) has a cable passage cavity (51) inside. The manhole (5) has a cable passage opening (52) connected to the cable passage cavity (51). The pipeline of the electromechanical equipment (4) passes through the cable passage opening (52) and the cable passage cavity (51) in sequence, passes through the top surface of the second building unit (2), passes through the deformation joint (9), passes through the curtain wall (3) and enters the interior of the first building unit (1). The cable passage opening (52) is provided with a water-blocking part (6) to prevent rainwater from entering the cable passage cavity (51). Waterproof eaves (7), the waterproof eaves (7) are set on the curtain wall (3). When viewed vertically, the waterproof eaves (7) can cover the expansion joint (9). The waterproof eaves (7) includes a first eave body (71), a second eave body (72), two connecting parts (73), and a support part (74). The two connecting parts (73) are respectively set at both ends of the curtain wall (3) in the first direction X. The two ends of the support part (74) in the first direction X are respectively connected to the two connecting parts (73). The first eave body (71) and the second eave body (72) are detachably installed on the support part (74). The first eave body (71), the second eave body (72) and the facade of the curtain wall (3) together form a receiving cavity (75) for receiving the support part (74).
2. The existing building pipeline transition drainage structure according to claim 1, characterized in that, A drainage ditch (8) is provided between the electromechanical equipment (4) and the manhole (5). The top surface of the waterproof eaves (7) has a first drainage slope toward the manhole (5), and the manhole (5) has a second drainage slope toward the drainage ditch (8).
3. The existing building pipeline transition drainage structure according to claim 1, characterized in that, It also includes a waterstop (10), and a first sealant (11) is connected between the top surface of the manhole (5) and the bottom surface of the waterproof eaves (7). One end of the waterstop (10) is set on the waterproof eaves (7), and the other end of the waterstop (10) is attached to the upper end of the manhole (5) through the first sealant (11).
4. The existing building pipeline transition drainage structure according to claim 1, characterized in that, It also includes a foam filling board (12), which is disposed in the expansion joint (9), and the two sides of the foam filling board (12) are respectively connected to the curtain wall (3) and the manhole (5).
5. The existing building pipeline transition drainage structure according to claim 4, characterized in that, The lower end of the foam filling board (12) is provided with a fire-resistant strip (13).
6. The existing building pipeline transition drainage structure according to claim 5, characterized in that, A drainage channel (14) is provided between the curtain wall (3) and the second building unit (2), and the drainage channel (14) is located below the fire barrier (13).
7. The existing building pipeline transition drainage structure according to claim 6, characterized in that, The drainage channel (14) has a third drainage slope.
8. The existing building pipeline transition drainage structure according to claim 1, characterized in that, The water-blocking part (6) includes a rainproof louver (61) disposed at the wire passage (52).
9. The existing building pipeline transition drainage structure according to claim 1, characterized in that, The cable outlet (52) is also provided with a drying section (15), which is located inside the water-blocking section (6).
10. The existing building pipeline transition drainage structure according to claim 9, characterized in that, The drying section (15) includes a drying fan (151).