A highway cable air-laying construction method

Abstract

This invention relates to the field of communication optical cable laying engineering technology, and discloses a method for air-blowing laying of highway cables. The method uses silicon core pipes between adjacent manholes or handholes as construction units. A pipe-driving tool is used to detect unobstructed flow, collecting data on length, turning positions, pipe drop, and water blockage to generate pipe section resistance indicators. The cable appearance, end sealing, and optical performance are inspected, and the cable outer diameter, allowable tension, and coiling direction are read to generate cable laying indicators. These two types of indicators are matched to generate blowing pressure, auxiliary traction force, cable feeding speed, and reel release speed. The cable is guided through an optical cable tray to a blowing machine, where high-pressure airflow is input and used for traction. During construction, surge, torsion, jamming, and small loop risks are assessed and parameters are corrected. After completion, cutting, splicing, heat fusion protection, junction box sealing, and optical performance retesting are performed to improve laying efficiency and reduce damage. The application of air-blowing construction technology extends the optical cable laying distance, reduces the number of joints, and thus reduces signal attenuation.

Description

Technical Field

[0001] This invention relates to the field of communication optical cable laying engineering technology, and in particular to a method for air-blowing laying of highway cables. Background Technology

[0002] As a crucial component of modern transportation infrastructure, the stability and reliability of communication systems directly impact the operational safety and management efficiency of highways. With the rapid development of information technology, highway construction and maintenance are increasingly becoming more intelligent and networked. Fiber optic communication, as a high-speed, stable, and high-capacity communication method, is widely used in highway communication systems. However, current highway fiber optic cable construction still faces numerous technical challenges and efficiency bottlenecks, urgently requiring systematic process research and optimization solutions.

[0003] The aforementioned and existing related technologies often suffer from the following drawbacks: Traditional construction methods, such as the traction method for laying optical cables, suffer from short cable-laying distances and slow speeds due to the high coefficient of friction within the duct walls, and are prone to mechanical stretching damage to the light rays. The traditional traction method is inefficient, resulting in a high rate of optical cable damage, severely impacting the stability and lifespan of the communication system. Furthermore, the complex construction environment of highways, with high traffic volume and short construction windows, places higher demands on construction techniques. Summary of the Invention

[0004] The technical problem to be solved by this invention is that the traditional traction method in the prior art has the disadvantages of high pipeline friction, short cable laying distance, slow speed and easy damage to optical cables. It can no longer meet the requirements of high efficiency and high quality laying process for the complex traffic and short construction window of highways. Therefore, we propose a gas blowing laying method for highway cables.

[0005] To achieve the above objectives, this application adopts the following technical solution: a method for air-blowing installation of highway cables, comprising the following steps: S1. Using the silicon core pipe between adjacent manholes or handholes as a construction unit, a pipe inserter is used to detect the unobstructed state inside the pipe, and the pipe section length, turning position, pipe opening drop and water accumulation blockage status are collected to generate pipe section resistance indicators. S2. Inspect the cable appearance, end sealing and optical performance, read the cable outer diameter, allowable tension and winding direction, install the cable reel on the roller and bracket and generate cable laying mark; S3. Match the pipe section resistance marking with the cable laying marking to generate an initial parameter set for the cable blowing pressure of the cable blowing machine, the auxiliary traction force of the traction machine, the cable feeding speed, and the cable reel laying speed. S4. The cable is guided into the cable blowing machine through the optical cable bracket. The cable blowing machine inputs high-pressure airflow into the silicon core tube, and the traction machine applies auxiliary traction force to the cable reinforcing core. S5. Collect data on cable entry speed, reel speed, auxiliary traction force, and pipe bending status to assess surge, torsion, jamming, and small loop risks. S6. Based on the risk assessment results, adjust the cable blowing pressure, cable feeding speed, auxiliary traction force, and cable reel release speed to ensure that the construction bending radius is not less than 20 times the cable radius. S7. After the cable reaches the target manhole or handhole, use cable cutters to cut the end according to the remaining length, prepare the end face of the fiber optic splice, perform fusion splicing, fix the protective heat fusion tube and seal the junction box, and retest the optical performance to confirm the laying quality.

[0006] Preferably, the pipe section resistance marking consists of length marking, turning marking, drop marking, water accumulation marking, and blockage marking. The location where the pipe inserter is obstructed in the silicon core pipe is marked with a blockage marking, and the location where the pipe inserter carries out water or mud and sand is marked with a water accumulation marking. The turning marking and drop marking are used to increase the correction weight of the cable blowing pressure of the cable blowing machine, and the water accumulation marking and blockage marking are used to decrease the correction weight of the cable feeding speed.

[0007] Preferably, the cable laying markings consist of cable outer diameter markings, allowable tension markings, coiling direction markings, pre-laying optical performance markings, and end sealing markings; the coiling direction markings are used to determine the cable reel's laying direction on the roller, the allowable tension markings are used to determine the upper limit of the auxiliary traction force of the traction machine, and the pre-laying optical performance markings are used to determine the difference between the pre-laying and post-laying retest results.

[0008] Preferably, the initial parameter set in S3 is generated according to the following steps: S31. Determine the cable blowing pressure of the cable blowing machine foundation based on the pipe section length; S32. Adjust the cable blowing pressure of the cable blowing machine foundation according to the turning position and the drop at the pipe opening; S33. Determine the cable feeding speed level based on the cable outer diameter; S34. Determine the upper limit of the auxiliary traction force of the traction machine based on the allowable tension. The upper limit of the auxiliary traction force shall not exceed 80% of the maximum allowable tension of the cable. S35. Determine the matching relationship between the cable reel feeding speed and the cable blowing machine feeding speed according to the cable winding direction.

[0009] Preferably, the optical cable tray is positioned between the cable reel and the cable blowing machine, and the guiding direction of the optical cable tray is consistent with the cable inlet direction of the cable blowing machine. When the cable swing amplitude at the optical cable tray increases and the reel speed fluctuates, this state is written into the surge risk, and the cable feeding speed of the reel and the cable blowing machine are reduced as linkage correction actions.

[0010] Preferably, the risk of jamming in S5 is determined and handled according to the following conditions: S51. When the cable feeding speed of the cable blowing machine is lower than the cable unloading speed of the cable reel and the auxiliary traction force of the traction machine continues to increase, it is judged as a risk of jamming. S52. First, reduce the cable feeding speed of the cable blowing machine and increase the cable blowing pressure; S53. If the auxiliary traction force continues to increase, stop cable feeding; S54. Use a pipe threading tool to perform reverse pipe verification of the silicon core tube from an adjacent manhole or handhole. S55. After the reverse pipe inspection is passed, the cable blowing construction will resume.

[0011] Preferably, the torsion risk in S5 is determined and handled according to the following conditions: when the cable rotates in the opposite direction before the cable inlet of the cable blower, it is determined to be a torsion risk; in response to the torsion risk, the cable blowing machine is suspended, the cable reel release direction, the optical cable bracket guide angle and the cable inlet position of the cable blower are corrected, and the reel speed and cable entry speed are collected again after correction.

[0012] Preferably, the small loop risk is determined and handled according to the following conditions: when the construction bending radius corresponding to the pipe bending state is less than 20 times the cable radius, it is determined to be a small loop risk; for the small loop risk, stop cable feeding and readjust the cable routing in front of the pipe opening until the construction bending radius is restored to not less than 20 times the cable radius before continuing cable feeding.

[0013] Preferably, the end face preparation includes stripping the fiber coating with a stripper, cleaning the bare fiber with acetone, and cutting the fiber end face with a fiber cleaver. After the fusion splicer fused the fiber, the splice quality was judged based on the splice image displayed by the fusion splicer. If the splice was not qualified, the fiber end face was re-prepared and fused again until the splice image was qualified.

[0014] Preferably, when fixing the protective heat fusion tube, the length of the fiber optic coating covering both ends of the protective heat fusion tube should be no less than 10mm; during fiber optic splicing and heat fusion protection, the bending radius of the fiber should be no less than 40mm; before sealing the junction box, the inner wall of the junction box, the sealing strip and the groove should be wiped with alcohol; after sealing the junction box, the pipe section resistance mark, cable laying mark, initial parameter group, risk assessment result, parameter correction result and optical performance retest result should be written into the construction unit record table and used for parameter preset of adjacent construction units.

[0015] The technical effects and advantages of this invention are as follows: In this invention, by employing an air-blowing method to lay cables within pre-installed silicon core pipes along highways, the continuous friction and concentrated stretching between the cable and the inner wall of the pipe, common in traditional traction methods, can be reduced. This allows the cable to be laid over longer distances under the combined action of high-pressure airflow, cable blowing, and traction, thereby reducing the number of intermediate joints and mitigating signal attenuation and potential malfunctions caused by increased splicing points. Furthermore, by generating pipe section resistance markers and cable laying markers before construction, the pipe section length, turning positions, pipe drop, and water blockage status are combined with the cable's outer diameter, allowable tension, coiling direction, and pre-laying optical performance. This ensures that the blowing pressure, cable feeding speed, auxiliary traction force, and cable reel release speed are matched according to the construction unit status. This avoids issues like jamming, overstretching, and asynchronous cable laying caused by overly coarse parameter settings. By collecting data on cable entry speed, reel speed, auxiliary traction force, and pipe bending status during construction, it allows for timely assessment of surge, torsion, jamming, and small loop risks. Corrections can be made to the cable blowing pressure, cable delivery speed, auxiliary traction force, and reel laying speed, reducing the probability of damage to the optical cable's outer sheath, bending damage, and mechanical tensile failure. Through end-face preparation, fusion splicing, protective heat fusion tube fixing, junction box sealing, and optical performance retesting, it is possible to promptly confirm laying quality and control communication attenuation. By reusing construction records to adjacent construction units, it is possible to improve the efficiency and stability of continuous laying in complex road sections, different climates, and short construction windows. Attached Figure Description

[0016] The disclosure of this invention is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. In the drawings, the same reference numerals are used to refer to the same parts: Figure 1 This is a schematic diagram of the overall process of a method for air-blowing installation of highway cables according to the present invention. Figure 2 This is a schematic diagram of the air-blowing installation unit and equipment layout of an air-blowing installation method for highway cables according to the present invention. Figure 3 This is a schematic diagram illustrating the generation of pipe segment resistance markings in a method for air-blown laying of highway cables according to the present invention. Figure 4 This is a schematic diagram illustrating the identifier matching and initial parameter group generation of a method for air-blowing laying of highway cables according to the present invention. Figure 5 This is a schematic diagram of the air-blowing construction monitoring method for highway cable air-blowing installation according to the present invention. Figure 6 This is a schematic diagram illustrating the risk assessment and parameter correction of an air-blowing installation method for highway cables according to the present invention. Figure 7This is a schematic diagram illustrating the optical fiber end face preparation, splicing, sealing, and retesting of a method for air-blowing installation of highway cables according to the present invention. Figure 8 This is a construction unit record and a schematic diagram of the parameter preset of adjacent construction units for a method of air-blowing laying of highway cables according to the present invention. Detailed Implementation

[0017] It is readily understood that, based on the technical solution of this invention, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the invention. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solution of this invention and should not be considered as the entirety of the invention or as limitations or restrictions on the technical solution of this invention.

[0018] Reference Figures 1 to 8 As shown, this invention provides a technical solution: a method for air-blowing installation of cables for highways. This method uses pre-laid silicon core pipes between adjacent manholes or handholes along the highway as the construction object, defining a section of silicon core pipe between adjacent manholes or handholes as a construction unit. Before construction, the manholes, handholes, pipe openings, and equipment placement areas are cleaned, a dust-proof environment is set up, traffic safety precautions are taken, and tools such as rollers, supports, optical cable brackets, pipe pullers, traction machines, cable blowing machines, cable cutters, strippers, fiber optic cutters, fusion splicers, protective hot-melt tubes, junction boxes, communication tools, and cleaning tools are prepared. Construction personnel verify the optical cable model, specifications, and length to ensure they match design requirements and confirm that the silicon core pipes are ready for inspection and air-blowing operations. The specific implementation steps include the following: Step 1: Using the silicon core pipe between adjacent manholes or handholes as a construction unit, a pipe threading tool is used to check the unobstructed state of the pipe, collecting data on pipe section length, turning positions, pipe head drop, and water accumulation / blockage status to generate pipe section resistance indicators. The pipe section resistance indicators consist of length indicators, turning indicators, head drop indicators, water accumulation indicators, and blockage indicators. If the pipe threading tool can pass smoothly through the construction unit and does not carry out water, mud, sand, or debris upon retrieval, it is recorded as unobstructed. If the pipe threading tool is difficult to advance, stalls, cannot continue advancing, or experiences significantly increased retrieval resistance, the corresponding position is marked as blocked. If the pipe threading tool carries out water, mud, sand, or continuous watermarks appear at the pipe head during retrieval, the corresponding pipe section is marked as water accumulation. Construction personnel, combining pipeline data, on-site manhole and handhole locations, and pipe threading tool advancement status, record turning positions to form turning indicators; the elevation relationship between the two pipe heads confirms whether there is an unfavorable head drop in the cable blowing direction, forming head drop indicators. If there are signs of blockage or water accumulation, first perform pipe cleaning, drainage, or reverse pipe clearing verification. If the verification still fails, do not proceed with cable blowing construction.

[0019] The pipe section resistance indicator is used to identify the source of resistance during cable blowing construction; the length indicator is used to determine whether a construction unit is suitable for single-blow air-blowing laying; the bend and drop indicators are used to increase the selected cable blowing pressure level; the water accumulation and blockage indicators are used to reduce the cable delivery speed level and serve as a basis for determining whether pipe cleaning and verification are required. The pipe section resistance indicator uses length, bend, drop, water accumulation, and blockage as input conditions for subsequent parameter matching, allowing construction parameters to be adjusted according to the pipe section status.

[0020] Step two involves inspecting the cable's appearance, end seal, and optical performance. The cable's outer diameter, allowable tension, and coiling direction are recorded. The cable reel is then mounted on the roller and support, and a cable laying label is generated. This label consists of the cable's outer diameter, allowable tension, coiling direction, pre-laying optical performance, and end seal markings. Construction personnel check the cable's outer sheath for flattening, scratches, tears, and moisture damage. They also check the end seal for integrity and confirm the cable end is not submerged in water. The cable's outer diameter and maximum allowable tension are recorded using the sheath markings or construction data. The laying direction is confirmed by the cable reel markings and coiling status. The initial state of each fiber core is obtained through pre-laying optical performance testing. Cables with visibly damaged outer sheaths, substandard end seals, or abnormal pre-laying optical performance are not permitted to proceed with the cable blowing process.

[0021] After the cable reel is installed on the shaft and bracket, its stable rotation should be ensured. The cable is led out in the correct direction, guided by the optical cable tray, and then enters the cable blowing machine. The optical cable tray is positioned between the cable reel and the cable blowing machine, with its guiding direction consistent with the cable inlet direction of the cable blowing machine to prevent lateral bending, slack accumulation, and reverse twisting of the optical cable before it enters the machine. The winding direction marking is used to determine the cable reel's laying direction; the allowable tension marking is used to determine the upper limit of the auxiliary traction force of the traction machine. The traction force for laying the optical cable must not exceed 80% of the maximum allowable tension of the optical cable, and the instantaneous traction force must not exceed 100% of the maximum allowable tension of the optical cable. The main traction force is applied to the reinforcing core; the optical performance marking before laying is used for comparison with the results of post-laying retesting.

[0022] Step 3: Match the pipe section resistance markings with the cable laying markings to generate initial parameter sets for the cable blowing pressure of the cable blowing machine, the auxiliary traction force of the traction machine, the cable delivery speed, and the cable reel laying speed. The matching rules for the parameter sets are as follows: When the pipe section resistance markings indicate that the pipe section is unobstructed, without water accumulation or blockage, and the impact of bends and drops is minimal, use conventional cable blowing pressure, conventional cable delivery speed, and synchronous cable laying method; when the pipe section resistance markings indicate that the pipe section is long, has bends, or has unfavorable drops, increase the selected level of cable blowing pressure and decrease the selected level of cable delivery speed; when the pipe section resistance markings indicate the presence of water accumulation or blockage records, first complete pipe cleaning or verification, and then use a low-speed stable cable delivery method. The cable outer diameter marking is used to determine the cable delivery speed level. Optical cables with smaller outer diameters are more prone to slack and small loops before the pipe opening, so the cable delivery speed should be reduced and the cable laying should be kept synchronous; the allowable tension marking is used to limit the auxiliary traction force of the traction machine, and the upper limit of the auxiliary traction force shall not exceed 80% of the maximum allowable tension; the coiling direction marking is used to determine the direction of reel rotation and cable laying, so that the optical cable is laid synchronously and evenly.

[0023] The initial parameter set is generated according to the following steps: S31. Determine the cable blowing pressure of the cable blowing machine foundation based on the pipe section length. When the pipe section length is within the applicable range of single air blowing laying, determine the cable blowing pressure selection level in combination with the pipe section resistance marking. S32. Adjust the cable blowing pressure of the cable blowing machine foundation according to the turning position and the drop at the pipe opening. When there are turning marks or unfavorable drop marks for laying to a higher position, increase the cable blowing pressure selection level. S33. Determine the cable feeding speed level based on the cable outer diameter. If the cable outer diameter is small or loosening and accumulation are likely to occur before the pipe opening, reduce the cable feeding speed level. S34. Determine the upper limit of the auxiliary traction force of the traction machine based on the allowable tension. The upper limit of the auxiliary traction force shall not exceed 80% of the maximum allowable tension of the cable, and the instantaneous traction force shall not exceed 100% of the maximum allowable tension of the cable. S35. Determine the matching relationship between the cable reel unloading speed and the cable feeding speed of the cable blowing machine according to the cable winding direction, so that the cable reel unloading speed and the cable feeding speed are synchronized and uniform, and avoid the optical cable from accumulating in front of the pipe or being excessively pulled.

[0024] Step four: The cable is guided into the cable blowing machine via the cable tray. The cable blowing machine supplies high-pressure airflow to the silicon core tube, and the traction machine applies auxiliary traction force to the cable's reinforcing core. At startup, the cable blowing machine is turned on first to supply air, creating a stable airflow within the silicon core tube. Then, the cable feeding mechanism is activated, allowing the cable to enter the silicon core tube under the combined action of the high-pressure airflow, the cable blowing machine, and the traction machine. During construction, the cable reel rotation should be synchronized and uniform with the cable laying to avoid surges, twisting, and small loops. Communication should be maintained between manholes, handholes, and equipment operating positions, under the unified command of a designated person. Untrained personnel are not allowed to work, and operations must not be carried out without communication facilities.

[0025] Step 5: Collect data on cable entry speed, reel speed, auxiliary traction force, and conduit bending status to assess surge, torsion, jamming, and small loop risks. Cable entry speed is obtained from the cable feeding status of the cable blower, the cable length fed per unit time, or the movement of on-site markers; reel speed is determined by the reel rotation status and the uniformity of cable release; auxiliary traction force is obtained from the traction machine display value or on-site recorded value; conduit bending status is verified according to the requirement that the bending radius of the optical cable during construction must not be less than 20 times the optical cable radius. The above information is recorded in the construction unit record sheet for risk assessment and parameter correction.

[0026] Surge risk is determined and handled according to the following conditions: S51. When the optical cable at the optical cable bracket shows alternating tension and swaying, the cable reel rotates erratically, and the optical cable in front of the pipe outlet shows short-term accumulation or shaking, it is judged as a surge risk. S52. To mitigate surge risk, reduce the cable reel unloading speed and the cable feeding speed of the cable blowing machine; S53. Adjust the guide direction of the optical cable tray to keep the direction of the optical cable entering the cable blowing machine straight; S54. Observe the rotation of the reel and the entry of the cable. After confirming that the cable laying is synchronized and uniform, continue the construction.

[0027] The risk of being stuck is determined and handled according to the following conditions: S55. When the cable feeding speed of the cable blowing machine is lower than the cable unloading speed of the cable reel, and the auxiliary traction force of the traction machine continues to increase, it is judged as a risk of jamming. S56. To address the risk of jamming, first reduce the cable feeding speed of the cable blowing machine and increase the cable blowing pressure. S57. If the auxiliary traction force continues to increase, stop cable feeding; S58. Use a pipe threading tool to perform reverse pipe verification of the silicon core tube from an adjacent manhole or handhole. S59. After the reverse pipe passage verification is passed, the cable blowing construction shall be resumed; if the reverse pipe passage verification still shows blockage, the construction of this construction unit shall be suspended and the silicon core tube shall be cleaned or repaired.

[0028] Risk of reversal is determined and handled according to the following conditions: S510. When the optical cable rotates in the opposite direction before entering the cable blowing machine, the cable reel's laying direction is inconsistent with the winding direction marking, or the optical cable undergoes continuous twisting before entering the cable blowing machine, it is judged as a twisting risk. S511. Stop the cable blowing machine from feeding the cable and correct the cable reel laying direction, optical cable bracket guide angle and cable blowing machine inlet position. S512. Arrange the optical cable before the pipe opening to ensure that the optical cable enters the pipe straight from the cable reel to the cable blowing machine. S513. After correction, re-observe the rotation of the reel and the entry of the cable. Continue construction after confirming that the cable laying is stable.

[0029] Small-circle risks are determined and handled according to the following conditions: S514. When the bending radius of the optical cable in front of the pipe is less than 20 times the radius of the optical cable, it is judged as a small loop risk. S515. Stop feeding the cable and straighten the optical cable route in front of the duct opening, and increase the bending radius in front of the duct opening. S516. Adjust the position of the optical cable bracket or add temporary guide supports until the construction bending radius is restored to not less than 20 times the optical cable radius before continuing to send the cable. S517. After the optical cable is laid, the remaining coil and fixation should have a bending radius of not less than 15 times the radius of the optical cable.

[0030] Step Six: Based on the risk assessment results, adjust the cable blowing pressure, cable delivery speed, auxiliary traction force, and cable reel release speed to ensure that the bending radius during construction is not less than 20 times the optical cable radius. In case of surge risk, reduce the cable reel release speed and the cable blowing machine's cable delivery speed, and adjust the optical cable tray guide direction; in case of jamming risk, reduce the cable delivery speed and increase the cable blowing pressure. If the auxiliary traction force still increases, stop the machine and reverse the flow through the conduit for verification; in case of torsion risk, pause cable delivery and correct the cable reel release direction, optical cable tray guide angle, and cable blowing machine inlet position; in case of small loop risk, stop cable delivery and tidy up the optical cable routing before the conduit opening; if optical cable damage is found, repair or replace it promptly. After parameter correction, record the pre-correction state, risk type, correction actions, and post-correction stable state in the construction unit record table.

[0031] Step 7: After the cable reaches the target manhole or handhole, use cable cutters to cut the end to the remaining length. Prepare the fiber end face, perform fusion splicing, fix the protective heat fusion tube, and seal the junction box. Retest the optical performance to confirm the laying quality. End face preparation includes stripping the fiber coating with a stripper, cleaning the bare fiber with acetone, and cutting the fiber end face with a fiber optic cleaver. If the end face is unqualified, recut it. After fusion splicing, monitor the estimated fusion value and observe the splice image. If the splice is unqualified, re-prepare the fiber end face and splice again until it is qualified. When fixing the protective heat fusion tube, the ends should cover the fiber coating by at least 10mm after shrinkage; the bending radius during fiber splicing should be at least 40mm. Before sealing the junction box, wipe the inner wall of the junction box, the sealing strip, and the groove with alcohol. Assembly should be performed according to the operating procedures. The ends of optical cables must be strictly sealed to prevent moisture and must not be submerged in water; unfinished optical cables must not be left in unattended outdoor areas; optical cables with a diameter of less than 12mm should be protected by conduits at manholes, handholes, or equipment room inlet holes, and manholes, handholes, and equipment room inlet holes should be sealed with cotton yarn or wire mesh soaked in rodenticide.

[0032] After construction, optical performance is retested at suspicious points, splices, and terminations, and the results are compared with the optical performance markings before laying. If any abnormalities are found, priority should be given to checking locations where surges, torsion, jamming, or small loops occurred during construction, as well as splices, termination seals, and pipe bends; any confirmed cable damage should be repaired or replaced promptly. The average attenuation coefficient of optical cable lines constructed using the air-blowing method is controlled to be below 0.2 dB / km, while the average attenuation coefficient of traditional traction methods is typically 0.35-0.4 dB / km. Through air-blowing laying, risk assessment, and dynamic correction, cable damage and the number of splices can be reduced, meeting the needs of high-definition video surveillance and real-time data transmission on highways.

[0033] The construction unit record sheet is used for parameter presetting of the next construction unit. The record sheet includes pipe section resistance identification, cable laying identification, initial parameter group, risk assessment results, parameter correction results, optical performance retest results, and anomaly handling results. When adjacent construction units use optical cables of the same specification and have similar duct conditions, the cable blowing pressure level, cable delivery speed level, auxiliary traction force control status, and cable reel release synchronization status during the stable laying of the previous construction unit should be used as the parameter preset basis for the next construction unit. If the next construction unit is longer, has more bends, more unfavorable drops, or has water accumulation and blockage, the cable blowing pressure level should be increased and the cable delivery speed level reduced based on this. If the previous construction unit has a surge risk, the cable reel release synchronization and optical cable bracket guidance should be checked carefully before the start of the next construction unit. If the previous construction unit has a jamming risk, the duct clearance verification requirements should be increased and the traction force should be controlled before the start of the next construction unit. If the previous construction unit has a torsion risk, the winding direction and cable inlet alignment should be checked before the start of the next construction unit. If the previous construction unit has a small loop risk, a straighter cable inlet path should be reserved before the start of the next construction unit, and the construction bending radius should be checked. If the optical performance retest of the previous construction unit is abnormal, its parameter records should not be directly used; the cause should be identified and repaired first.

[0034] Example: In the construction of a communication pipeline on a highway, a section of silicon core pipe between two adjacent manholes was used as a construction unit. The measured length of this section was 820m, the inner diameter of the silicon core pipe was 40mm, there was a bend at a 35-degree angle, and the opening of the starting manhole was 2.2m lower than the opening of the target manhole. A small amount of accumulated water and mud was brought out during pipe pulling. The outer diameter of the optical cable used was 12mm, the cable radius was 6mm, the maximum allowable tension was 2000N, the bending radius during construction was not less than 120mm, and the bending radius during fiber optic splicing and thermal fusion protection was not less than 40mm. Based on the above information, length markers, bend markers, drop markers, water accumulation markers, cable outer diameter markers, allowable tension markers, coiling direction markers, and pre-laying optical performance markers were generated, and this construction unit was determined to be a high-resistivity pipe section.

[0035] Table 1: Basic Data and Identification Usage of Construction Units

[0036] Based on the pipe section resistance markings and cable laying markings, the construction personnel generated an initial parameter set. The cable blowing pressure of the cable blowing machine was set to 0.70 MPa, the cable feeding speed of the cable blowing machine was set to 40 m / min, the cable reel laying speed was set to 41 m / min, the initial auxiliary traction force of the traction machine was set to 800 N, and the auxiliary traction force alarm value was set to 1600 N. During construction, the cable blowing machine was first turned on to input high-pressure airflow into the silicon core tube, and then the cable feeding mechanism and traction machine were started to allow the optical cable to smoothly enter the cable blowing machine through the optical cable bracket. The cable reel was laid out in the reverse direction of the winding direction, and the cable reel laying speed was kept synchronized with the cable feeding speed of the cable blowing machine to avoid cable slack and accumulation in front of the pipe opening.

[0037] Table 2: Initial Parameter Set and Risk Correction Parameter Table

[0038] When construction reached the 360m mark, the cable sway at the fiber optic cable tray increased to 25mm, and the reel rotation speed fluctuated significantly, indicating a surge risk. The construction team immediately reduced the cable feeding speed of the cable blower from 40m / min to 38m / min and the cable release speed of the reel from 41m / min to 38m / min. They also adjusted the guide angle of the fiber optic cable tray to align the cable with the cable inlet of the blower. After adjustment, the cable sway decreased to below 15mm, the reel rotation returned to uniformity, and construction continued according to the corrected parameters.

[0039] When construction reached the 610m mark, the cable-feeding machine showed a cable-feeding speed of 32m / min, while the cable-laying speed remained at 38m / min. The auxiliary traction force of the traction machine increased from 800N to 1050N and continued to rise, indicating a risk of jamming. Construction personnel reduced the cable-feeding speed to 30m / min and increased the cable-feeding pressure from 0.70MPa to 0.75MPa, while observing changes in the auxiliary traction force. After adjustment, the auxiliary traction force stabilized below 1100N, and the cable-feeding speed returned to 30m / min, not exceeding the 1600N upper limit, allowing construction to continue. If the auxiliary traction force continues to rise, cable feeding will be stopped, and a pipe-threading device will be used to reverse the pipe flow from the target manhole for verification.

[0040] After the optical cable reaches the target manhole, a 15m allowance is reserved according to the design. The end is cut with cable cutters and immediately sealed for moisture protection. During splicing, the fiber coating is stripped using a stripper, the bare fiber is cleaned with acetone, and then the end face is cut with a fiber optic cleaver; if the end face is not up to standard, it is recut. After the fusion splicer completes the splicing, the estimated fusion value and splicing image are observed. If the splicing is not up to standard, the end face is re-prepared and fusion is performed again. When fixing the protective heat fusion tube, the length of the fiber coating covering both ends of the protective heat fusion tube is not less than 10mm. Before sealing the junction box, the inner wall of the junction box, the sealing strip, and the groove are wiped with alcohol. After sealing, the optical performance is retested. The retest results show that the average attenuation coefficient of this construction unit is 0.18dB / km, which is lower than 0.2dB / km. No suspicious damage points were found, and the laying quality is judged to be qualified.

[0041] Table 3: Construction Unit Record Contents and Adjacent Construction Unit Reuse Rules

[0042] If the next adjacent construction unit still uses 12mm outer diameter optical cable, and the pipe section length is within the range of 780m to 850m, the following parameters can be preset: cable blowing pressure of 0.75MPa, cable delivery speed of 30m / min to 38m / min, auxiliary traction force not exceeding 1100N, and cable reel release speed synchronized with cable delivery speed. If the next pipe section has fewer bends and no water accumulation, the cable delivery speed should be restored to 38m / min to 40m / min, and the cable blowing pressure reduced to 0.70MPa to 0.72MPa. After this record sheet is reused, the next construction unit does not need to start with blank parameters for trial adjustment, which can reduce the number of surge, jamming, torsion, and small loop risks, and improve the laying efficiency within the short construction window of the highway.

[0043] By identifying pipe section length, bends, elevation differences, cement and sand conditions, and cable laying parameters before construction, pipe section resistance and cable laying indicators are generated, and an initial parameter set is determined accordingly. During cable blowing, the blowing pressure, cable delivery speed, auxiliary traction force, and cable reel laying status are adjusted based on the risks of surges, jamming, torsion, and small loops. After construction, the risk assessment, parameter corrections, and optical performance retest results are recorded in the construction unit record table and reused for parameter presetting in adjacent construction units. This reduces repeated trial adjustments, lowers the probability of optical cable damage within the short construction window of highways, and improves the stability and construction efficiency of continuous pipe section air-blown laying.

[0044] The technical scope of this invention is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this invention, and all such modifications and variations should fall within the protection scope of this invention.

Claims

1. A method of highway cable air blast installation construction, characterized by, Includes the following steps: S1. Using the silicon core pipe between adjacent manholes or handholes as a construction unit, a pipe inserter is used to detect the unobstructed state inside the pipe, and the pipe section length, turning position, pipe opening drop and water accumulation blockage status are collected to generate pipe section resistance indicators. S2. Inspect the cable appearance, end sealing and optical performance, read the cable outer diameter, allowable tension and winding direction, install the cable reel on the roller and bracket and generate cable laying mark; S3. Match the pipe section resistance marking with the cable laying marking to generate an initial parameter set for the cable blowing pressure of the cable blowing machine, the auxiliary traction force of the traction machine, the cable feeding speed, and the cable reel laying speed. S4. The cable is guided into the cable blowing machine through the optical cable bracket. The cable blowing machine inputs high-pressure airflow into the silicon core tube, and the traction machine applies auxiliary traction force to the cable reinforcing core. S5. Collect data on cable entry speed, reel speed, auxiliary traction force, and pipe bending status to assess surge, torsion, jamming, and small loop risks. S6. Based on the risk assessment results, adjust the cable blowing pressure, cable feeding speed, auxiliary traction force, and cable reel release speed to ensure that the construction bending radius is not less than 20 times the cable radius. S7. After the cable reaches the target manhole or handhole, use cable cutters to cut the end according to the remaining length, prepare the end face of the fiber optic splice, perform fusion splicing, fix the protective heat fusion tube and seal the junction box, and retest the optical performance to confirm the laying quality.

2. A method of highway cable blowing installation according to claim 1, characterized in that: The pipe section resistance markings consist of length markings, turning markings, drop markings, water accumulation markings, and blockage markings. The location where the pipe threader is obstructed in the silicon core pipe is marked as a blockage marking, and the location where the pipe threader carries out water or mud is marked as a water accumulation marking. The turning markings and drop markings are used to increase the correction weight of the cable blowing pressure of the cable blowing machine, while the water accumulation markings and blockage markings are used to decrease the correction weight of the cable feeding speed.

3. The method of claim 1, wherein: The cable laying markings consist of cable outer diameter markings, allowable tension markings, coiling direction markings, pre-laying optical performance markings, and end sealing markings. The coiling direction markings are used to determine the cable reel's laying direction on the roller, the allowable tension markings are used to determine the upper limit of the auxiliary traction force of the traction machine, and the pre-laying optical performance markings are used to determine the difference between the pre-laying and post-laying retest results.

4. The method of claim 1, wherein: The initial parameter set in S3 is generated according to the following steps: S31. Determine the cable blowing pressure of the cable blowing machine foundation based on the pipe section length; S32. Adjust the cable blowing pressure of the cable blowing machine foundation according to the turning position and the drop at the pipe opening; S33. Determine the cable feeding speed level based on the cable outer diameter; S34. Determine the upper limit of the auxiliary traction force of the traction machine based on the allowable tension. The upper limit of the auxiliary traction force shall not exceed 80% of the maximum allowable tension of the cable. S35. Determine the matching relationship between the cable reel feeding speed and the cable blowing machine feeding speed according to the cable winding direction.

5. The method of claim 1, wherein: The optical cable bracket is installed between the cable reel and the cable blowing machine, and the guiding direction of the optical cable bracket is consistent with the cable inlet direction of the cable blowing machine. When the cable swing amplitude at the optical cable tray increases and the cable reel speed fluctuates, this state is written into the surge risk, and the cable reel feeding speed and the cable blowing machine feeding speed are reduced as linkage correction actions.

6. A method of air blowing a highway cable according to claim 1, wherein: The risk of jamming in S5 is determined and handled according to the following conditions: S51. When the cable entering speed of the cable blowing machine is lower than the cable release speed of the cable reel and the auxiliary traction force of the traction machine continues to increase, it is judged as a risk of jamming. S52. First, reduce the cable feeding speed of the cable blowing machine and increase the cable blowing pressure; S53. If the auxiliary traction force continues to increase, stop cable feeding; S54. Use a pipe threading tool to perform reverse pipe verification of the silicon core tube from an adjacent manhole or handhole. S55. After the reverse pipe inspection is passed, the cable blowing construction will resume.

7. A method of highway cable air-laying construction according to claim 6, wherein: The torsion risk in S5 is determined and handled according to the following conditions: when the cable rotates in the opposite direction before the cable inlet of the cable blowing machine, it is determined to be a torsion risk; in response to the torsion risk, the cable blowing machine is suspended from feeding the cable, the cable reel release direction, the optical cable bracket guide angle and the cable blowing machine inlet position are corrected, and the reel rotation speed and cable entry speed are collected again after correction.

8. A method of highway cable blowing installation according to claim 7, characterised in that: The small circle risk is determined and handled according to the following conditions: when the construction bending radius corresponding to the pipe opening bending state is less than 20 times the cable radius, it is determined to be a small circle risk; for the small circle risk, stop cable feeding and readjust the cable routing in front of the pipe opening until the construction bending radius is restored to not less than 20 times the cable radius before continuing cable feeding.

9. A method of air blowing a highway cable according to claim 1, wherein: The end face preparation includes stripping the fiber coating with a stripper, cleaning the bare fiber with acetone, and cutting the fiber end face with a fiber cleaver. After the fusion splicer fused the fiber, the splice quality was judged based on the splice image displayed by the fusion splicer. If the splice was not qualified, the fiber end face was re-prepared and fused again until the splice image was qualified.

10. The method of claim 1, wherein: When the protective heat fusion tube is fixed, the length of the fiber coating covering both ends of the protective heat fusion tube shall not be less than 10mm; during the fiber splicing and heat fusion protection process, the bending radius of the fiber shall not be less than 40mm. Before sealing the junction box, wipe the inner wall of the junction box, the sealing strip and the groove with alcohol. After sealing the junction box, write the pipe section resistance mark, cable laying mark, initial parameter group, risk assessment result, parameter correction result and optical performance retest result into the construction unit record table, and use it for parameter preset of adjacent construction units.

Images