A new open-cut cable tunnel and the connection structure of the built municipal comprehensive pipe gallery

Abstract

The application relates to the technical field of open excavation cable tunnel construction, and discloses a connection structure of a newly-built open excavation cable tunnel and an existing municipal comprehensive pipe gallery, which comprises the existing municipal comprehensive pipe gallery and existing cables laid in the existing municipal comprehensive pipe gallery; a newly-built open excavation cable tunnel is arranged above the existing municipal comprehensive pipe gallery; the bottom plate of the newly-built open excavation cable tunnel is combined with the top plate of the existing municipal comprehensive pipe gallery to form a shared middle cross partition plate; a rectangular hole is arranged on the middle cross partition plate; the newly-laid cables in the newly-built open excavation cable tunnel enter the existing municipal comprehensive pipe gallery through the rectangular hole and are arranged in parallel with the existing cables; the two side edges of the middle cross partition plate are extended in the longitudinal direction to form a cantilever plate structure; the application has the advantages of wide adaptability to urban cable expansion, line addition and reconstruction engineering, convenient construction, low difficulty and low comprehensive cost through the reinforcing design of the upper and lower combined 'day' shaped overall structure and the double-side cantilever plate structure.

Description

Technical Field

[0001] This invention relates to a connection structure between a newly constructed open-cut cable tunnel and an existing municipal utility tunnel, belonging to the technical field of open-cut cable tunnel construction. Background Technology

[0002] With the continuous advancement of new urbanization in my country, underground municipal utility tunnels, as the core carrier of urban infrastructure, have been widely adopted in major and medium-sized cities. Among them, the power compartments of these tunnels serve as the main channels for laying high-voltage and medium-voltage cables, undertaking the core functions of power transmission and distribution in the city's main power grid, and are crucial underground structures ensuring a stable urban power supply. Currently, most common municipal utility tunnels are trunk channels planned as a whole for a specific area and constructed simultaneously. During the construction phase, they primarily meet the current power deployment needs, making it difficult to comprehensively predict the refined needs of long-term urban power expansion, new lines, and cable connections. This leads to a situation where, in subsequent urban power grid upgrades and new power supply projects, new open-cut cable tunnels need to be constructed to connect with existing municipal utility tunnels. However, existing municipal utility tunnels generally have high structural safety levels, deep burial depths, and thick overburden, and already contain a large number of in-use cables, supporting supports, and maintenance equipment. This results in limited overall construction space and stringent maintenance conditions for urban power grid upgrades and new power supply projects.

[0003] To achieve a safe connection between a newly constructed cable tunnel and an existing utility tunnel without interrupting power supply or damaging the existing structure, while avoiding interference between newly laid cables and existing cables and ensuring convenient maintenance and upkeep in the future, the following utility model patents exist: Chinese Patent Application No. CN202520664498.5 discloses a junction node between a utility tunnel and a power tunnel. By placing the power tunnel above the utility tunnel at the junction node, if a power tunnel compartment needs to be added later, construction can be carried out simply by removing the top slab of the utility tunnel at the connection point, greatly reducing the difficulty and cost of reconstruction. Another utility model patent, Chinese Patent Application No. CN202123061868.7, discloses a connection structure between an existing power tunnel and a newly constructed power tunnel. By setting the new power tunnel at the bottom of the existing power tunnel, it solves the connection problem between the existing and new power tunnels within a limited space, avoiding the adverse effects of a horizontal connection between the new and existing power tunnels on the existing power system.

[0004] However, these two methods have the following problems in practical application: For the technical solution disclosed in the utility model patent with the application number CN202520664498.5, it is only applicable to the new construction project scenarios with synchronous planning and simultaneous construction, and it cannot adapt to the working conditions of the subsequent secondary access and capacity expansion and renovation of the existing pipe galleries, with insufficient pertinence.

[0005] For the technical solution disclosed in the utility model patent with the application number CN202123061868.7, due to the generally large cross-sectional dimensions, large buried depths, and thick overburdens of the existing urban integrated pipe galleries, it is necessary to excavate ultra-deep foundation pits during construction, greatly increasing the construction difficulty and project cost; and there are many cable brackets pre-embedded inside the side walls of the pipe galleries and cables are laid, and the construction is extremely likely to disturb the original facilities. Summary of the Invention

[0006] In order to solve the above problems existing in the prior art, the present invention provides a connection structure between a newly built open-cut cable tunnel and an existing municipal integrated pipe gallery.

[0007] The technical solution of the present invention is as follows: A connection structure between a newly built open-cut cable tunnel and an existing municipal integrated pipe gallery, including an existing municipal integrated pipe gallery and cables already laid in the existing municipal integrated pipe gallery. A newly built open-cut cable tunnel is arranged above the existing municipal integrated pipe gallery. The bottom plate of the newly built open-cut cable tunnel and the top plate of the existing municipal integrated pipe gallery are overlapped to form a common intermediate transverse partition. The newly built open-cut cable tunnel forms a "day" - shaped structure through the up-and-down overlap with the existing municipal integrated pipe gallery. A rectangular hole is opened on the intermediate transverse partition. The newly laid cables laid in the newly built open-cut cable tunnel can enter the existing municipal integrated pipe gallery through the rectangular hole and be arranged in parallel with the already laid cables to ensure the consistency of cable layout. Both side edges of the intermediate transverse partition extend longitudinally to form a cantilever structure. The specific longitudinal extension length of the cantilever structure can be selected according to the actual situation, and it is preferred to be the same as the length at the overlapping position of the newly built open-cut cable tunnel and the existing municipal integrated pipe gallery. The cantilever structure can play a role in strengthening the overlapping structure of the newly built open-cut cable tunnel and the existing municipal integrated pipe gallery.

[0008] It should be noted that the overlapping part of the bottom plate of the newly built open-cut cable tunnel and the top plate of the existing municipal integrated pipe gallery can be selected according to the actual situation. Usually, the newly built open-cut cable tunnel forms a trajectory with an arc-shaped middle from the side position of the existing municipal integrated pipe gallery to directly above the existing municipal integrated pipe gallery. Therefore, the bottom plate of the straight overlapping part of the newly built open-cut cable tunnel and the existing municipal integrated pipe gallery and the top plate of the existing municipal integrated pipe gallery are overlapped to form the intermediate transverse partition.

[0009] To ensure the connection strength between the bottom slab of the newly constructed open-cut cable tunnel and the top slab of the existing municipal utility tunnel, further, a number of interface connecting bars are provided in the area where the middle cross partition does not have rectangular holes. The specific quantity and distribution of the interface connecting bars can be selected and set according to the actual situation. The interface connecting bars fixedly connect the bottom slab of the newly constructed open-cut cable tunnel and the top slab of the existing municipal utility tunnel. At the same time, the depth of the interface connecting bars anchored into the bottom slab of the newly constructed open-cut cable tunnel and the top slab of the existing municipal utility tunnel is not less than 15 times their own diameters to ensure the connection effect.

[0010] Further, the surface of the top slab of the existing municipal utility tunnel is also roughened to enhance its bonding force with the bottom slab of the newly constructed open-cut cable tunnel during the subsequent casting process of the bottom slab of the newly constructed open-cut cable tunnel, making the interface combination firm and not prone to problems such as delamination and hollowing.

[0011] To enhance the structural strength of the two side cantilever slabs to ensure their reinforcement effect, further, a number of transversely distributed cantilever slab transverse bars and a number of longitudinally distributed cantilever slab longitudinal bars are provided in the structures of the two side cantilever slabs. The specific distribution of the cantilever slab transverse bars and the cantilever slab longitudinal bars in the structures of the two side cantilever slabs can be selected and set according to the actual situation.

[0012] To meet the laying requirements of the newly laid cables, further, the rectangular holes are longitudinally spaced on the middle cross partition. The construction of the rectangular holes can adopt a low-disturbance cutting process to ensure minimal impact on the existing municipal utility tunnel and the laid cables inside it. The number of rectangular holes is set to be adapted to the number of circuits of the newly laid cables to ensure that each newly laid cable can enter the existing municipal utility tunnel through the corresponding rectangular hole. The size of the rectangular holes meets the laying and turning radius requirements for the newly laid cables to be laid into the existing municipal utility tunnel through the rectangular holes.

[0013] To ensure that the above connection structure can be put into use smoothly, further, the width of the overlapping part between the newly constructed open-cut cable tunnel and the existing municipal utility tunnel is set to be adapted to the width of the existing municipal utility tunnel, specifically, they are equal, so that the "day"-shaped overlapping structure can be formed smoothly and thus have the corresponding structural strength. The length of the overlapping part between the newly constructed open-cut cable tunnel and the existing municipal utility tunnel meets the laying and operation and maintenance requirements of the newly laid cables. A steel ladder is also provided between the newly constructed open-cut cable tunnel and the existing municipal utility tunnel to form a maintenance passage for maintenance personnel. The steel ladder can be arranged at the middle position of one of the rectangular holes. If the steel ladder is selected to be arranged in the rectangular hole, the size of the rectangular hole is also set to meet the space requirements for setting the steel ladder in the maintenance passage.

[0014] The interior of the newly built open-cut cable tunnel is also provided with a fireproof partition wall, and a fireproof door is arranged inside the fireproof partition wall. The interior of the newly built open-cut cable tunnel is also provided with an anti-backflow wall, the height of the anti-backflow wall is not less than 0.5 m, steps are arranged on both sides of the anti-backflow wall, and the arrangements of the fireproof partition wall, the fireproof door and the anti-backflow wall enable the above-mentioned connection structure to have the required fireproof property and anti-backflow property.

[0015] The present invention has the following beneficial effects: By arranging the newly built open-cut cable tunnel on the existing municipal utility tunnel, the bottom slab of the newly built open-cut cable tunnel and the top slab of the existing municipal utility tunnel are overlapped to form a shared intermediate diaphragm, and a cantilever slab structure is arranged on both sides of the intermediate diaphragm and a rectangular hole for the newly laid cable to pass through is opened on the intermediate diaphragm. Through the reinforcement design of the "day" - shaped integral structure with upper and lower overlap + double - side cantilever slab structure, the coordinated force - bearing of the new and old structures and the structural reinforcement of the opening area are realized, and at the same time, multiple functions of anti - floating, pressure reduction and bearing capacity enhancement are achieved. Meanwhile, there is no need to deeply excavate the foundation pit and no need to construct on the side wall position of the existing municipal utility tunnel (such as making lateral openings, etc.), so as to avoid disturbing the internal facilities of the existing municipal utility tunnel. Compared with the prior art, it has the advantages of wide adaptability to urban cable capacity expansion, new line addition and renovation projects, low construction difficulty and low comprehensive cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Fig. 1 is the plan layout drawing of the embodiment of the present invention; Fig. 2 is the longitudinal section layout drawing of the embodiment of the present invention; Fig. 3 is the transverse section layout drawing of the embodiment of the present invention; Fig. 4 is the simplified structural mechanics model diagram of the embodiment of the present invention.

[0017] The reference signs in the drawings are represented as: 1. Existing municipal utility tunnel; 2. Existing laid cable; 3. Newly built open - cut cable tunnel; 4. Intermediate diaphragm; 5. Rectangular hole; 6. Newly laid cable; 7. Cantilever slab structure; 8. Interface connecting bar; 9. Cantilever slab transverse bar; 10. Cantilever slab longitudinal bar; 11. Steel ladder; 12. Fireproof partition wall; 13. Anti - backflow wall; 14. Step. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] The present invention will be described in detail below with reference to the drawings and specific embodiments.

[0019] Embodiment: Please refer to Figs. 1-4, in this embodiment, when a newly built open-cut cable tunnel 3 is connected to an existing municipal integrated utility tunnel 1 in the later stage, there are technical pain points such as great difficulty in structural connection, easy disturbance of the original structure, large interference in cable laying, high construction cost, mismatched reserved interfaces, and high risk of side opening. A connection structure between the newly built open-cut cable tunnel and the existing municipal integrated utility tunnel is provided. By setting a "day" - shaped connection structure that overlaps up and down, on the premise of ensuring the structural safety of the existing municipal integrated utility tunnel 1 and the normal operation of the already laid cables 2, efficient, safe, and economical connection of the new and old tunnels is achieved, adapting to the scenarios of urban existing utility tunnel expansion and new cable access projects. The following will make a detailed description of this embodiment in combination with specific structural parameters, construction techniques, and functional designs.

[0020] I. Overall Structural Arrangement and Core Dimension Parameters The overall layout of this connection structure adopts an up - and - down overlapping type. Taking the existing municipal integrated utility tunnel 1 as the lower chamber and the newly built open - cut cable tunnel 3 as the upper chamber, a combined overall "day" - shaped cross - section structure is formed, completely avoiding the defects of the traditional side - opening connection method, such as large excavation depth, high reinforcement difficulty, and easy interference with the original cables. The width of the overlapping part between the newly built open - cut cable tunnel 3 and the existing municipal integrated utility tunnel 1 is the same as the width of the existing municipal integrated utility tunnel 1, ensuring the overall regularity and force stability of the structure. The length of the overlapping part between the newly built open - cut cable tunnel 3 and the existing municipal integrated utility tunnel 1 is set to 5.95m, which can fully meet the space requirements for the smooth laying, turning arrangement, and later personnel operation and maintenance of the newly laid cables 6.

[0021] The standard dimensions of each structure are as follows: The internal clearance size of the existing municipal integrated utility tunnel 1 is 2.7m×4.0m, and the wall thickness is 0.35m; the internal clearance size of the newly built open - cut cable tunnel 3 is 2.7m×2.4m, and the wall thickness is 0.35m. The bottom slab of the newly built open - cut cable tunnel 3 overlaps with the top slab of the existing municipal integrated utility tunnel 1 to form a shared intermediate diaphragm 4. The total thickness of the overlapping slab is 0.7m, including the thickness of the existing municipal integrated utility tunnel 1 of 0.35m. After the combination of the new and old structures, a complete overall force - bearing system is formed. The radius of the central axis of the curve section of the newly built open - cut cable tunnel 3 is set to 4.7m to ensure the smooth transition of the line.

[0022] Both sides of the intermediate diaphragm 4 extend longitudinally along the newly built open - cut cable tunnel 3 to form a cantilever slab structure 7. The length of the single - side cantilever of the cantilever slab structure 7 is 1.25m, which can effectively expand the bearing area of the structure foundation, reduce the foundation pressure, and at the same time enhance the structural integrity and anti - deformation ability of the subsequent opening area of the intermediate diaphragm 4, compensating for the structural strength loss after the opening of the top slab of the existing municipal integrated utility tunnel 1. In addition, after the excavation of the upper soil body, the self - weight of the overlapping structure decreases and the anti - floating performance weakens. The double - side cantilever slab structure 7 can significantly improve the anti - floating stability of the overall structure, and at the same time enhance the bearing capacity of the overall structure to resist horizontal soil pressure, equivalently playing the role of strengthening the reinforcement beam.

[0023] II. Four-hole design in the middle horizontal partition To enable the continuous laying of cables and personnel access for maintenance within the existing municipal utility tunnel 1 and the newly built open-cut cable tunnel 3, rectangular holes 5 are opened longitudinally at intervals on the intermediate transverse partition 4. The number of holes can be flexibly adapted according to the actual number of cable circuits, and the hole size strictly conforms to the cable diameter and the minimum turning radius requirements of the standard, so as to avoid cross-interference between new and old cables from the source.

[0024] In this embodiment, two types of standardized openings can be set: opening 1 has a size of 2.7m × 2.1m, and opening 2 has a size of 2.7m × 1.1m; the interval between adjacent openings is 1m, and a safety distance of 0.5m is reserved between opening 2 and the end wall of the newly built open-cut cable tunnel 3. Actual measurements show that the turning radius of the newly laid cable 6 is controlled within the range of 2.0m to 3.2m, fully meeting the minimum bending radius requirement of the 20D operating specification for the newly laid cable 6, thus eliminating cable bending damage and potential discharge hazards. Simultaneously, the use of intermittent openings avoids weakening the structural strength of the existing municipal utility tunnel 1's roof slab with large-area continuous openings, minimizing the impact on the main load-bearing system of the existing municipal utility tunnel 1.

[0025] The entire process of opening the roof slab of the existing municipal utility tunnel 1 was carried out using diamond wire saw cutting technology. This technology has the advantages of high precision, low vibration, low noise, and no dust pollution, which can minimize the disturbance to the original structure of the existing municipal utility tunnel 1, the internal cables 2, and the surrounding soil. For large openings, a segmented cutting scheme was adopted, dividing the concrete of the opening into 2-3 independent hoisting blocks, with the weight of each block strictly controlled between 6-10 tons, which facilitates safe on-site hoisting and reduces construction difficulty.

[0026] III. Reinforcement Design for Connection Between New and Old Structures To achieve structural integration between the existing municipal utility tunnel 1 and the newly constructed open-cut cable tunnel 3, a composite connection process of roughening the top slab of the existing municipal utility tunnel 1 and the bottom slab of the newly constructed open-cut cable tunnel 3, consisting of interface connecting bars 8, is adopted. Before construction, the bonding surface of the top slab of the existing municipal utility tunnel 1 is thoroughly roughened to remove surface laitance and debris, ensuring a tight bond between the old and new concrete surfaces and preventing interface cracking and water seepage.

[0027] The interface connecting reinforcement 8 uses 14mm diameter rebars, spaced at 150mm intervals, with an effective length of 200mm for each rebar. The main rebars penetrate deep into the top slab and side walls of the existing municipal integrated pipe gallery 1, with the anchorage depth strictly adhering to the specification requirement of not less than 15 times the diameter of the rebar, ensuring the anchorage strength of the rebars. Simultaneously, bidirectional reinforcing bars are configured in the area of ​​the cantilever slab structure 7 on both sides. The longitudinal reinforcement 10 and transverse reinforcement 9 of the cantilever slab both use 14mm diameter rebars spaced at 150mm intervals, comprehensively enhancing the reinforcement, anti-buoyancy, and bearing capacity of the cantilever slab.

[0028] After the reinforcement is laid out, special side and bottom formwork is erected, and micro-expansion fine stone concrete with a strength one grade higher than that of the original structure is used for pouring. The concrete is vibrated and compacted throughout the process to eliminate quality defects such as honeycomb, pitting, and voids. After pouring, routine curing is carried out, and the formwork can only be removed after the concrete strength reaches 100% of the design strength to ensure the overall strength, stiffness, and integrity of the composite structure.

[0029] IV. Design of Ancillary Operation and Maintenance and Safety Protection Structure 1. Maintenance access structure: A steel ladder 11 is installed between the newly built open-cut cable tunnel 3 and the existing municipal integrated pipe gallery 1 to effectively eliminate the height difference between the upper and lower maintenance access channels, providing a safe and convenient vertical access channel for maintenance personnel to conduct daily inspections, equipment maintenance, and cable maintenance, and meeting long-term maintenance needs.

[0030] 2. Fireproof partition structure: Fireproof partitions 12 are installed inside the newly built open-cut cable tunnel 3. Fireproof doors are installed in the middle of the fireproof partitions 12 to realize fireproof partitions in sections of the tunnel, effectively blocking the spread of fire and smoke, eliminating the risk of large-scale safety hazards caused by single point failures, and improving the overall fire safety level of the cable tunnel.

[0031] 3. Backflow prevention structure: The interior of the newly built open-cut cable tunnel 3 is equipped with a backflow prevention wall 13 with a height of not less than 0.5m. Steps 14 are arranged on both sides of the backflow prevention wall 13. This can effectively prevent rainwater, water accumulation and debris from flowing back into the pipe gallery, ensuring that the interior is dry and clean and the equipment operates safely, without affecting the normal passage and maintenance of personnel.

[0032] V. Preliminary Verification and Key Construction Processes 1. Preliminary alignment verification: Before construction, priority is given to verifying the horizontal alignment, vertical height difference and spatial relationship between the existing municipal integrated utility tunnel 1 and the newly built open-cut cable tunnel 3. The alignment of the newly built open-cut cable tunnel 3 is finely adjusted according to the actual access position of the existing municipal integrated utility tunnel 1 to ensure accurate connection between the old and new structures and smooth connection of the line, thus solving the industry pain points of misalignment of pre-reserved interfaces, size mismatch and inability to connect lines in traditional projects.

[0033] 2. Opening optimization principle: Based on the actual turning trajectory of the cable, the installation space of the steel ladder 11, and the needs of personnel passage, the opening position and size are refined and optimized. Under the premise of meeting the functions of laying and operation and maintenance, the scale of the opening in the top plate is minimized to the greatest extent, the structural integrity of the existing municipal integrated pipe gallery 1 is preserved to the greatest extent, and the risk of structural stress weakening is reduced.

[0034] 3. Standardized construction of wire saw cutting: First, use a water drill to drill holes at the corners and midpoints of the long side of the cutting line, and open Φ100mm through guide holes as the channel for the wire saw chain to pass through; then, accurately install the positioning guide rail and active and passive guide wheels, calibrate the cutting line to completely coincide with the construction ink line, and fix the wire saw main unit to ensure that the equipment is stable and secure; finally, thread the diamond beaded rope to form a closed cutting loop, and tension it to the design tension through the hydraulic system to complete the cutting operation at a uniform speed, ensuring that the cutting surface is flat and the accuracy is controllable.

[0035] 4. Layered cable layout: The newly laid cable 6 is uniformly arranged in the upper part of the internal structure of the existing municipal integrated pipe gallery 1, and is arranged in layers with the existing cable 2. This completely avoids the problem of crossover and mutual interference between new and old cables, ensures the stable operation of the cables, and facilitates later zonal maintenance, replacement and capacity expansion.

[0036] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A connection structure between a newly constructed open-cut cable tunnel and an existing municipal utility tunnel, comprising an existing municipal utility tunnel (1) and a pre-laid cable (2) laid within the existing municipal utility tunnel (1), characterized in that: A new open-cut cable tunnel (3) is set above the existing municipal integrated pipe gallery (1). The bottom plate of the new open-cut cable tunnel (3) and the top plate of the existing municipal integrated pipe gallery (1) are superimposed to form a shared intermediate diaphragm (4). A rectangular hole (5) is opened on the intermediate diaphragm (4). The newly laid cable (6) laid in the new open-cut cable tunnel (3) enters the existing municipal integrated pipe gallery (1) through the rectangular hole (5) and is set parallel to the laid cable (2). The two sides of the intermediate diaphragm (4) extend longitudinally to form a cantilever structure (7).

2. The connection structure between a newly constructed open-cut cable tunnel and an existing municipal integrated utility tunnel according to claim 1, characterized in that: Several interface connecting bars (8) are set in the area where the rectangular holes (5) are not opened in the intermediate diaphragm (4). The interface connecting bars (8) fix the bottom plate of the newly built open-cut cable tunnel (3) to the top plate of the existing municipal integrated pipe gallery (1).

3. The connection structure between a newly constructed open-cut cable tunnel and an existing municipal integrated utility tunnel according to claim 2, characterized in that: The surface of the top plate of the existing municipal integrated pipe gallery (1) has been roughened.

4. The connection structure between a newly constructed open-cut cable tunnel and an existing municipal integrated utility tunnel according to claim 2, characterized in that: The depth to which the interface connecting bar (8) is anchored into the bottom slab of the newly built open-cut cable tunnel (3) and the top slab of the existing municipal integrated pipe gallery (1) is not less than 15 times its own diameter.

5. The connection structure between a newly constructed open-cut cable tunnel and an existing municipal integrated utility tunnel according to claim 1, characterized in that: Both sides of the cantilever structure (7) are provided with several horizontally distributed cantilever horizontal ribs (9) and several vertically distributed cantilever longitudinal ribs (10).

6. The connection structure between a newly constructed open-cut cable tunnel and an existing municipal integrated utility tunnel according to claim 1, characterized in that: The rectangular holes (5) are arranged longitudinally on the middle transverse partition (4). The number of rectangular holes (5) is adapted to the number of loops of the newly laid cable (6). The size of the rectangular holes (5) meets the requirements for the laying and turning radius of the newly laid cable (6) when it is laid into the existing municipal integrated pipe gallery (1) through the rectangular holes (5).

7. The connection structure between a newly constructed open-cut cable tunnel and an existing municipal integrated utility tunnel according to claim 1, characterized in that: The width of the newly built open-cut cable tunnel (3) and the existing municipal integrated pipe gallery (1) overlaps with the width of the existing municipal integrated pipe gallery (1), and the length of the newly built open-cut cable tunnel (3) and the existing municipal integrated pipe gallery (1) overlaps meets the requirements for laying and maintenance of the new cable (6).

8. The connection structure between a newly constructed open-cut cable tunnel and an existing municipal integrated utility tunnel according to claim 1, characterized in that: A steel ladder (11) is installed between the newly built open-cut cable tunnel (3) and the existing municipal integrated pipe gallery (1) to form a maintenance passage.

9. The connection structure between a newly constructed open-cut cable tunnel and an existing municipal integrated utility tunnel according to claim 1, characterized in that: The newly constructed open-cut cable tunnel (3) is equipped with a fireproof partition wall (12), and a fireproof door is installed inside the fireproof partition wall (12).

10. The connection structure between a newly constructed open-cut cable tunnel and an existing municipal integrated utility tunnel according to claim 1, characterized in that: The newly constructed open-cut cable tunnel (3) is equipped with an anti-backflow wall (13) with a height of not less than 0.5m. Steps (14) are arranged on both sides of the anti-backflow wall (13).

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