Construction method for laying sensing optical cable on track traffic ballast bed

Abstract

The invention discloses a construction method for laying a sensing optical cable on a track traffic ballast bed. The construction method comprises the following steps: 1) acquiring information data of a to-be-constructed track traffic line; 2) dividing a to-be-constructed rail transit line into an embedding method laying section, a surface mounting method laying section and a special treatment section; (3) the whole rail transit line is divided into small construction units, and each construction unit serves as a stage to arrange a construction plan; (4) according to the construction plan, construction is conducted on each construction unit; (5) carrying out splicing / welding treatment, namely leading the optical cable to the tunnel wall along the ballast bed surface at the breakpoint of the optical cable, protecting the melting point by using a wire box after welding, fixing the wire box on the tunnel wall by using a fixture, and then testing the signal strength; and 6) debugging and acceptance inspection: converging the optical cable into a station machine room for debugging and acceptance inspection.

Description

Technical Field

[0001] The present invention relates to the field of rail transportation technology, and more particularly to a construction method for laying a sensor optical cable on a rail transportation roadbed. Background Art

[0002] The intelligent transformation of urban rail transit requires the support of advanced sensing technology. Fiber optic sensing technology has matured in recent years and features continuous and dense coverage, making its application in this continuous, long-range structure of urban rail transit highly practical.

[0003] To realize the application of fiber optic sensing technology in rail transit, the primary challenge is how to safely, quickly, and reliably lay the sensor cables longitudinally along the trackbed. This is especially true for lines already in operation. This ensures that the installation does not disrupt the next day's rail transit operations, existing equipment, or routine rail transit maintenance. Therefore, a comprehensive, reliable, and efficient construction plan is urgently needed.

[0004] Currently, most projects for laying sensor optical cables on the track bed are test sections with short lengths and no systematic construction methods. Therefore, after being tested in harsh conditions such as vibration loads from rail transit trains and humidity, peeling, cracking, and curling will occur in a short period of time, seriously affecting operational safety.

[0005] Therefore, a new sensor optical cable laying technology is needed to at least partially overcome the problems existing in the prior art. Summary of the Invention

[0006] The present invention mainly addresses the above-mentioned deficiencies in the prior art and aims to provide a complete set of construction methods for laying sensor optical cables on the roadbed of urban rail transit, which is used to guide the laying of sensor optical cables on the roadbed without affecting the normal operation of rail transit, damaging existing equipment and facilities, and affecting the maintenance of rail equipment.

[0007] According to one aspect of the present invention, a construction method for laying a sensor optical cable on a rail transit roadbed is provided, comprising:

[0008] 1) Obtain information on the rail transit lines to be constructed;

[0009] 2) Based on the acquired information, the rail transit line to be constructed is divided into three types of sensor cable laying: buried laying section, surface mounting laying section, and special treatment section;

[0010] 3) Determine the station where the machine room is to be located based on the basic information of the rail transit line. Combined with the mileage of each section, the entire rail transit line is divided into smaller construction units, and each construction unit is considered as a stage in the construction plan.

[0011] 4) Carry out construction for each construction unit according to the construction plan, including:

[0012] In the buried laying section, a laser level is used to locate the tangent line, which is 100 to 300 mm from the right edge of the trackbed in the direction of the rail transit. A slotting machine is used to cut a slot in the trackbed slab longitudinally along the rail transit line. The raised cement residue at the bottom of the slot is ground and cleaned. The sensor optical cable is then buried in the slot, and the cable is straightened as much as possible. Quick-hardening grouting material is used for filling and covering shallow burial. After the grouting material hardens, the surface is polished and smoothed with a grinder.

[0013] In the surface-mounting section, use an angle grinder to remove stains on the roadbed surface; remove dust from the roadbed surface; use carbon fiber impregnated adhesive to bond the optical cable and use carbon fiber cloth to cover it;

[0014] Special treatment sections are selected from the ends of steel spring floating plates, ends of high-vibration damping roadbeds, track-crossing pipelines, trackside equipment, civil air defense doors, and transition areas between high-vibration damping roadbeds and other roadbeds. Installation treatment is carried out separately for each special treatment section.

[0015] 5) Splicing / fusion splicing, which includes guiding the optical cable along the roadbed surface to the tunnel wall at the breakpoint of the optical cable, protecting the melting point with a wire box after fusion, and fixing the wire box to the tunnel wall with a clamp, and then testing the signal strength;

[0016] 6) Debugging and acceptance, including bringing the optical cables into the station machine room for debugging and acceptance.

[0017] According to an embodiment of the present invention, the tangent is 100 to 300 mm away from the right edge of the track bed in the forward direction of the rail transit, and the groove size is approximately width (15-20) mm*depth (10-12) mm.

[0018] According to an embodiment of the present invention, step 2) further comprises determining the mileage location of the optical cable breakpoint based on information of the rail transit line.

[0019] According to the embodiment of the present invention, the construction method for laying sensor optical cables on the track bed of rail transit further includes, before the construction, performing a pre-laying process of optical cables to spread the optical cables along the laying path; including using line clips to fix them at intervals of 2-3m in the slotted sections, fixing the optical cables according to the completion standards at the detours, tying the cables in the surface-mounted laying sections with pre-set optical cable brackets, and using strong adhesive tape or quick-adhesive powder to temporarily reinforce the middle of each track bed plate.

[0020] According to the embodiment of the present invention, the optical cable pre-laying process includes fixing the cables at intervals of 2-3m using line clips in the slotted section, fixing the optical cables in accordance with the completion standards at the detour, tying the cables in the surface-mounted laying section with pre-installed optical cable brackets, and temporarily reinforcing the middle of each track bed plate using strong tape or quick-adhesive powder.

[0021] According to an embodiment of the present invention, the special treatment sections are selected from the ends of steel spring floating plates, ends of advanced vibration-damping roadbeds, track crossing pipelines, trackside equipment, civil defense doors, and transition areas between advanced vibration-damping roadbeds and other roadbeds.

[0022] According to an embodiment of the present invention, when the special treatment section is the end of the high-vibration damping track bed plate, the optical cable is passed through a cable bracket (10) pre-fixed at the seam of the high-vibration damping track bed plate, and the cable bracket is installed no higher than the track bed surface.

[0023] According to an embodiment of the present invention, the cable bracket (10) includes a base (11) and a support plate (12), the support plate extends vertically upward from a part of the side of the base (11), and is formed with a through hole (121) and a groove (122) at the upper end, and the optical cable is arranged in the groove (122) and is bound using the through hole (121).

[0024] According to the implementation scheme of the present invention, when the special treatment section is the end of the steel spring floating plate, if there is no shear plate at the end of the steel spring floating plate but only a sealing strip, the optical cable is laid by the embedding method, and the sealing strip is temporarily removed during laying, and the optical cable is embedded under the sealing strip, and finally the sealing strip is restored; if there is a shear plate and a sealing strip at the end of the steel spring floating plate, the grooving machine cannot operate here, and the optical cable is laid here instead of embedded, and is surface-mounted below the sealing strip.

[0025] When the special treatment section is a pipeline crossing the track, whether the optical cable is installed by burial or surface mounting, first try to pass it under the pipeline crossing the track without affecting the existing function. If it is not possible to pass it under the pipeline, cross it over the pipeline. The upper part of the optical cable is protected by an elastic sleeve;

[0026] When the special treatment section is trackside equipment, the optical cable will be routed to the left track for further laying. After passing the trackside equipment, it will return to the right track for further laying. If it is not possible to route to the left track, it will be routed away from the rails along the junction of the roadbed and the tunnel wall.

[0027] When the special treatment section is a civil air defense door, the optical cable is laid to the civil air defense door, passed along the joint between the rail and the door sill and fixed; if the joint between the rail and the door sill cannot be passed, the optical cable is routed along the door sill to the reserved threading hole outside the door frame of the civil air defense door and the threading hole is sealed with fireproof putty after the construction is completed;

[0028] When the special treatment section is the transition zone between the high-vibration damping track bed and other track beds, the optical cable of the high-vibration damping track bed is laid on the inner side of the rail, and the other track beds are laid on the outer side of the rail. At the transition point, the optical cable passes under the rail to realize the conversion between the inside and outside of the rail. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of a process for laying a sensor optical cable on a rail transit roadbed according to an embodiment of the present invention;

[0030] Figure 2 Schematic diagram of the cross-sectional structure after laying the sensor optical cable using the embedding method and the surface mounting method in the construction method of laying the sensor optical cable on the rail transit roadbed according to the embodiment of the present invention;

[0031] Figure 3 (a) and (b) are schematic diagrams of the buried process structure of the construction method for laying a sensor optical cable on a rail transit roadbed according to an embodiment of the present invention;

[0032] Figure 4 A schematic diagram of the surface mounting process structure of a construction method for laying a sensor optical cable on a rail transit roadbed according to an embodiment of the present invention;

[0033] Figure 5 A schematic diagram of laying a sensor optical cable at the end of a high-vibration damping roadbed according to a construction method for laying a sensor optical cable on a rail transit roadbed according to an embodiment of the present invention;

[0034] Figure 6 (a) and (b) are respectively a front view and a top view of a cable support for a construction method for laying a sensor optical cable on a railway track bed according to an embodiment of the present invention; and

[0035] Figure 7 Schematic diagram of a method for transitioning between an advanced vibration-damping roadbed and other roadbeds according to a construction method for laying a sensor optical cable on a rail transit roadbed according to an embodiment of the present invention. DETAILED DESCRIPTION

[0036] The present invention can be better understood with reference to the accompanying drawings and the following embodiments. However, it is easy for those skilled in the art to understand that the contents described in the embodiments are only used to illustrate the present invention, and should not and will not limit the present invention.

[0037] Figure 1 The following is a flow chart of a construction method for laying sensor optical cables on a rail transit roadbed according to an embodiment of the present invention. As shown in the figure, the construction scheme for laying sensor optical cables on a rail transit roadbed according to the embodiment is as follows:

[0038] (1) First, obtain information and data related to the rail transit line to be constructed, such as typical drawings and basic information. Basic information may include: line mileage, station mileage, civil air defense door mileage, trackbed type, turnouts, pump room, etc. Typical drawings may include: weak current professional route diagram, drawings of the equipment room to be deployed, plan and cross-section drawings of typical trackbed, typical tunnel type drawings, etc. This can be obtained by searching design materials, public information, etc.

[0039] In addition, due to the limitations of construction drawings and basic information on rail transit lines, it may not be possible to fully grasp the actual situation. Therefore, a detailed survey of the entire line can be conducted to record the conditions of special points and corresponding mileage information and other information.

[0040] (2) Based on the information obtained, the rail transit lines to be constructed are divided into three types of laying sensor optical cables, namely, buried laying sections, surface laying sections and special treatment sections.

[0041] The embedding method is a construction method in which a longitudinal groove of a suitable size is opened on the surface of the roadbed and then the optical cable is embedded. This method can effectively avoid interference from pulsating wind pressure and damage to the optical cable caused by other subsequent operations. Therefore, if conditions permit, the embedding method is preferred. The surface-mounting method is to apply the optical cable to the surface of the roadbed using carbon fiber cloth + carbon fiber impregnated adhesive. If the optical cable is armored, it can also prevent damage to the optical cable from other operations to a certain extent; however, the protection of the optical cable is still limited, so the surface-mounting method is only used in areas where grooving and embedding are not possible. The surface-mounting method is suitable for special points such as high-vibration damping roadbed plates (because high-vibration damping roadbed plates are prestressed roadbed plates and cannot be grooved) and plate ends (prefabricated steel spring floating plate roadbeds have shear plates at the ends of the roadbed plates, and the groover does not have enough operating space). Figure 2 This is a schematic diagram of the cross-sectional structure after laying the sensor optical cable using the embedding method and the surface mounting method in the construction method of laying the sensor optical cable on the rail transit roadbed according to the embodiment of the present invention.

[0042] In addition to areas suitable for general embedment and surface mounting methods, there are also some special areas, such as the ends of steel spring floating plates, the ends of high-vibration damping roadbeds, track-crossing pipelines, trackside equipment, civil air defense doors, the transition area between high-vibration damping roadbeds and other roadbeds, and machine rooms. Special treatment measures can be adopted for these areas / facilities.

[0043] More specifically, this step involves planning cable routes and equipment deployment stations. For example, based on the information from step 1 and equipment capabilities, optical cables are segmented (according to required accuracy and resolution, etc.), defining sensor cable paths, classifying special points, and handling methods. The mileage locations of optical cable breakpoints are determined, and the cabinet placement in the station machine room is selected. For example, if a certain type of optical fiber demodulation equipment has a maximum effective operating range of 5 km, the mileage information is used to determine the station machine room where the demodulation equipment is deployed. Based on basic line information and on-site surveys, it is recommended that breakpoints be set at civil air defense doors or at the transition between high-vibration damping trackbed and other trackbeds. The distance between breakpoints is the length of each reel of optical cable.

[0044] (3) Determine the station where the machine room is to be set up based on the basic information of the rail transit line, and divide the entire rail transit line into smaller construction units based on the mileage length of each section. Each construction unit is arranged as a stage in the construction plan.

[0045] For example, a construction unit plan could be designed as follows:

[0046] Day 1 to Day N: The trackbed is grooved and the machine room can be renovated;

[0047] Day N+1 to Day N+a: Roadbed polishing, fiber optic cable bracket installation, and machine room renovation.

[0048] On Days N+a+1 to N+b, optical cables are pre-laid and the equipment room can be renovated.

[0049] Day N+b+1 to Day N+c: Cable burial, surface mounting, and special treatment;

[0050] Days N+c+1 to N+d: The optical cable is connected to the machine room and the breakpoints are spliced;

[0051] Day N+d+1 to Day N+e: debugging;

[0052] Day N+e+1 to Day N+f, intermediate acceptance.

[0053] (4) Carry out construction for each construction unit according to the construction plan:

[0054] Before construction begins, pre-laying the optical cables can be done to spread the cables along the route. This involves using cable clips at 2-3m intervals in slotted sections, securing cables at detours according to completion standards, securing cables to pre-installed cable supports in surface-mounted sections, and temporarily reinforcing each track slab using strong tape or quick-tack powder. The goal of pre-laying the cables is to minimize cable breakage and reduce signal attenuation.

[0055] A. During the buried section, use a laser level to locate the tangent line, 100-300mm from the right edge of the trackbed in the direction of the rail transit's travel (to minimize frequent left and right translation of the optical cable. Alternatively, use the rail as a reference to locate the tangent line). Use a slotting machine to create a slot in the trackbed slab longitudinally along the rail transit line, with a slot size of approximately (15-20)mm wide and (10-12)mm deep. The slotting machine can be sprayed with water to both cool the track and reduce dust. The slotting process will generate some dust, which can be removed with a vacuum cleaner or by activating the tunnel exhaust. Note: A slotting machine with a power of 5-7kW is recommended. This power rating ensures both efficiency and ease of operation in most slotting locations. Also, note that the total power of a single-section, single-line, 100-meter rail transit power supply box is typically 15kW. Therefore, the work surface must be properly arranged to avoid overload tripping. Grind away any raised cement residue at the bottom of the trench and clean the trench. Then, bury the optical sensor cable in the trench, keeping it as straight as possible but avoiding any pulling. Use quick-hardening grouting material for shallow filling and covering. (The grouting material must meet the requirements of Section 6 of GB 50728-2011, "Specifications for Safety Assessment of Reinforcement Materials for Engineering Structures"). After the grouting material hardens, use a grinder to smooth the surface. Spray water and vacuum to avoid contamination. Figure 3 (a) and (b) are schematic diagrams of the embedding process structure.

[0056] B. During the surface-mounting section, use an angle grinder to remove surface stains from the roadbed (e.g., high-grade vibration-damping roadbed). This roadbed grinding process will generate a small amount of dust, which can be removed by turning on the tunnel exhaust and using a vacuum cleaner for local purification. Try to perform this work just before cable laying to avoid re-contamination due to prolonged idle time. Then, remove dust from the roadbed surface. Use carbon fiber impregnated adhesive to bond the optical cable (carbon fiber impregnated adhesive must meet the requirements of GB 50728-2011, Specification for Safety Assessment of Engineering Structure Reinforcement Materials), and cover with carbon fiber cloth. The order of attachment is primer, optical cable, carbon fiber cloth, and secondary adhesive application. Figure 4 Shown is a schematic diagram of the surface mount process structure.

[0057] C. Treatment of special treatment sections. Special treatment sections can be selected from the ends of steel spring floating plates, ends of high-vibration damping roadbeds, track crossing pipelines, trackside equipment, civil air defense doors, and transition areas between high-vibration damping roadbeds and other roadbeds.

[0058] When the special treatment section is the end of the steel spring floating plate, if there is no shear plate at the end of the steel spring floating plate but only a sealing strip, the optical cable is laid by the embedding method. During laying, the sealing strip is temporarily removed, the optical cable is embedded under the sealing strip, and finally the sealing strip is restored. If there is a shear plate and a sealing strip at the end of the steel spring floating plate, the grooving machine cannot operate here, and the optical cable is laid here instead of embedded, and the surface is attached below the sealing strip.

[0059] When the special treatment section is the end of the high-vibration damping track bed plate, the optical cable is passed through a cable bracket (10) fixed in advance at the seam of the high-vibration damping track bed plate, and the cable bracket is installed no higher than the track bed surface. Figure 5 A schematic diagram of the laying of the high-grade vibration-damping trackbed plate end is shown.

[0060] Figure 6 (a) and (b) are respectively a front view and a top view of a cable bracket for a construction method for laying a sensor optical cable on a rail transit track bed according to an embodiment of the present invention. As shown in the figure, the cable bracket (10) includes a base (11) and a support plate (12). A bolt hole (111) can also be formed on the base (11) for fixing the entire cable bracket (10); the support plate (12) extends vertically upward from a part of the side of the base (11), and is formed with a perforation (121) and a groove (122) at the upper end, and the optical cable is arranged in the groove (122) and is bound by the perforation (121). The support plate (12) extends vertically upward from a part of the side of the base (11), that is, the width of the support plate (12) is smaller than the width of the base (11). Such a design makes the cable bracket (10) more stable and takes up less space. In addition, during the processing and production of the bracket, only simple processes such as punching, bending, and shearing are required, which improves production efficiency and reduces costs.

[0061] When the special treatment section is a track pipeline, no matter whether the optical cable is constructed by burial or surface mounting, under the premise of not affecting the existing function, first try to pass it under the track pipeline. If it is impossible to pass it under, cross it over the pipeline, and put the upper part of the optical cable into an elastic sleeve for protection. In addition, the daily maintenance of related professional equipment should be considered when installing the optical cable, and a spacing of about 1 cm can be reserved to avoid interference between maintenance and replacement.

[0062] When the special treatment section is the trackside equipment, the optical cable will go around to the left track to continue laying, and after passing the trackside equipment, it will return to the right track to continue laying; if it is impossible to go around to the left track, it will go around along the junction of the roadbed surface and the tunnel wall in the direction away from the rail.

[0063] When the special treatment section is the civil air defense door, the optical cable is laid to the civil air defense door, passed along the joint between the steel rail and the door sill and fixed; if the joint between the steel rail and the door sill cannot be passed, the optical cable is routed along the door sill to the reserved wire hole outside the door frame of the civil air defense door and passed through. After the construction is completed, the wire hole is sealed with fire-proof putty.

[0064] When the special treatment section is the transition zone between the high-vibration damping track bed and other track beds, the high-vibration damping track bed optical cable is laid on the inner side of the rail, and the other track beds are laid on the outer side of the rail. At the transition point, the optical cable passes under the rail to realize the conversion between the inner and outer sides of the rail. Figure 6A schematic diagram of the transition treatment method between the advanced vibration-damping track bed and other track beds is shown.

[0065] (5) Perform splicing / fusion splicing. At the breakpoint of the optical cable, leave enough length at both ends of the optical cable (recommended 5 meters). Lead the optical cable along the roadbed to the tunnel wall. After fusion splicing, use a wire box to protect the melting point and fix the wire box to the tunnel wall with a clip. The excess optical cable is coiled into a coil with a diameter of about 0.5m and fixed to the tunnel wall with a wire clip (the coil is fixed at at least two points). The signal strength needs to be tested after each optical cable fusion (the signal attenuation of each construction unit shall not be greater than 0.8dB / km).

[0066] (6) Debugging and acceptance, including bringing the optical cables into the station machine room for debugging and acceptance.

[0067] The invention is the first to propose a complete and feasible plan for laying optical cables in rail transit roadbeds; the construction method of the invention has been compiled after field surveys of a large number of rail transit lines, basically covering all special locations, and customized treatment methods for all special locations; the plan specifically designs optical cable brackets for use between high-grade vibration-damping roadbed plates, which can not only meet the use requirements but also ensure the convenience of on-site construction. In addition, the processing and production of the brackets only require simple manufacturing processes such as shearing, punching and bending, which improves production efficiency and reduces costs; the construction method fully considers various precautions for construction in rail transit and can ensure smooth construction; the materials selected for construction refer to national standards, which ensures the quality of the project and provides a reference for the formulation of construction plans.

[0068] The above exemplary embodiments of the present invention are described, but the present invention is not limited to the embodiments described above. The basic concept of the present invention lies in the above basic scheme. For those skilled in the art, it does not require creative effort to design various modified models, formulas, and parameters based on the teachings of the present invention. Changes, modifications, substitutions, and variations of the embodiments without departing from the principles and spirit of the present invention remain within the scope of protection of the present invention.

Claims

1. A construction method for laying sensor optical cables on a rail transit roadbed, characterized in that: include: 1) Obtain information on the rail transit lines to be constructed; 2) Based on the acquired information, the rail transit line to be constructed is divided into three types of sensor cable laying: buried laying section, surface mounting laying section, and special treatment section; 3) Determine the station where the machine room is to be located based on the basic information of the rail transit line. Combined with the mileage of each section, the entire rail transit line is divided into smaller construction units, and each construction unit is considered as a stage in the construction plan. 4) Carry out construction for each construction unit according to the construction plan, including: In the buried laying section, a laser level is used to locate the tangent line, which is 100 to 300 mm from the right edge of the trackbed in the direction of the rail transit. A slotting machine is used to cut a slot in the trackbed slab longitudinally along the rail transit line. The raised cement residue at the bottom of the slot is ground and cleaned. The sensor optical cable is then buried in the slot, and the cable is straightened as much as possible. Quick-hardening grouting material is used for filling and covering shallow burial. After the grouting material hardens, the surface is polished and smoothed with a grinder. In the surface paving section, use an angle grinder to remove stains on the surface of the roadbed; remove dust from the surface of the roadbed; Use carbon fiber impregnated adhesive to bond the optical cables and use carbon fiber cloth to cover them; Special treatment sections are selected from the ends of steel spring floating plates, ends of high-vibration damping roadbeds, track-crossing pipelines, trackside equipment, civil air defense doors, and transition areas between high-vibration damping roadbeds and other roadbeds. Installation treatment is carried out separately for each special treatment section. 5) Splicing / fusion splicing, which includes guiding the optical cable along the roadbed surface to the tunnel wall at the breakpoint of the optical cable, protecting the melting point with a wire box after fusion, and fixing the wire box to the tunnel wall with a clamp, and then testing the signal strength; 6) Debugging and acceptance, including bringing the optical cables into the station machine room for debugging and acceptance.

2. The construction method for laying sensor optical cables on a rail transit roadbed according to claim 1, characterized in that: The tangent is 100 to 300 mm away from the right edge of the track bed in the direction of rail transit travel, and the groove size is approximately width (15-20) mm * depth (10-12) mm.

3. The construction method for laying sensor optical cables on a rail transit roadbed according to claim 1, characterized in that: Step 2) also includes determining the mileage location of the optical cable breakpoint based on information about the rail transit line.

4. The construction method for laying sensor optical cables on a rail transit roadbed according to claim 1, characterized in that: It also includes a pre-laying process of optical cables before construction to spread the optical cables along the laying path.

5. The construction method for laying sensor optical cables on a rail transit roadbed according to claim 4, characterized in that: The optical cable pre-laying process includes using line clips to fix at intervals of 2-3m in the slotted section, fixing the optical cable in accordance with the completion standard at the detour, tying the surface-mounted cable sections to pre-installed optical cable brackets, and temporarily reinforcing the middle of each track bed slab with strong tape or quick-adhesive powder.

6. The construction method for laying sensor optical cables on a rail transit roadbed according to claim 1, characterized in that: The special treatment sections are selected from the ends of steel spring floating plates, ends of advanced vibration-damping roadbeds, track-crossing pipelines, trackside equipment, civil air defense doors, and transition areas between advanced vibration-damping roadbeds and other roadbeds.

7. The construction method for laying sensor optical cables on a rail transit roadbed according to claim 6, characterized in that: When the special treatment section is the end of the high-vibration damping track bed plate, the optical cable is passed through a cable bracket (10) fixed in advance at the seam of the high-vibration damping track bed plate, and the cable bracket is installed no higher than the track bed surface.

8. The construction method for laying sensor optical cables on a rail transit roadbed according to claim 7, characterized in that: The cable bracket (10) comprises a base (11) and a support plate (12); the support plate extends vertically upward from a portion of the side of the base (11), and is formed with a through hole (121) and a groove (122) at the upper end; the optical cable is arranged in the groove (122) and is bound using the through hole (121).

9. The construction method for laying sensor optical cables on a rail transit roadbed according to claim 6, characterized in that: When the special treatment section is the end of the steel spring floating plate, if there is no shear plate at the end of the steel spring floating plate but only a sealing strip, the optical cable is laid by the embedding method. During laying, the sealing strip is temporarily removed, the optical cable is embedded under the sealing strip, and finally the sealing strip is restored; if there is a shear plate and a sealing strip at the end of the steel spring floating plate, the grooving machine cannot operate here, and the optical cable is laid here instead of embedded, and the surface is attached below the sealing strip. When the special treatment section is a pipeline crossing the track, whether the optical cable is installed by burial or surface mounting, first try to pass it under the pipeline crossing the track without affecting the existing function. If it is not possible to pass it under the pipeline, cross it over the pipeline. The upper part of the optical cable is protected by an elastic sleeve; When the special treatment section is trackside equipment, the optical cable will be routed to the left track for further laying. After passing the trackside equipment, it will return to the right track for further laying. If it is not possible to route to the left track, it will be routed away from the rails along the junction of the roadbed and the tunnel wall. When the special treatment section is a civil air defense door, the optical cable is laid to the civil air defense door, passed along the joint between the rail and the door sill and fixed; if the joint between the rail and the door sill cannot be passed, the optical cable is routed along the door sill to the reserved threading hole outside the door frame of the civil air defense door and passed through. After the construction is completed, the threading hole is sealed with fireproof putty (the treatment method depends on the needs of the rail transit operating unit. Under normal circumstances, in order to ensure the airtightness of the civil air defense door, additional facilities and equipment are not allowed at the door sill). When the special treatment section is the transition zone between the advanced vibration-damping track bed and other track beds, the optical cable of the advanced vibration-damping track bed is laid on the inner side of the rail, and the other track beds are laid on the outer side of the rail. At the transition point, the optical cable passes under the rail to realize the conversion between the inside and outside of the rail (if the advanced vibration-damping track bed is narrow on the inside and wide on the outside of the rail, the optical cable is laid along the outside of the rail. In this case, the transition point does not need to cross the rail and can be directly transitioned).

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