Currently, with the rapid development of the economy and science and technology, and the increasing intelligence of the informatization level, the construction of substations is also becoming more and more intelligent. Among them, cable tunnels are an important means for substations to achieve intelligence. Therefore, in practical applications, higher technical and quality requirements are needed. For example, to meet the needs of complex signal transmission, the cable tunnels in substations are required to crisscross for hundreds of meters. To ensure that various cables and signal carriers in the tunnels can work stably, cable tunnels need to provide a long-term and stable working environment to ensure that the substations can supply power reliably.
In addition, cable tunnels are an important part of substation projects, and their construction progress, efficiency, and quality affect the entire project. Especially in recent years, people have paid more and more attention to the project quality and operation effect of substations. Generally, the methods of brick-built cable tunnels or cast-in-place concrete cable tunnels are usually adopted. However, due to some objective reasons, it is difficult to meet the needs of new substation construction. Therefore, this article discusses the installation measures of prefabricated U-shaped concrete cable tunnels in substations and proposes solutions to the existing problems, hoping to provide some help for relevant workers.
A cable tunnel refers to an underground channel that is excavated and built by relevant construction workers according to design standards. Load-bearing angle steel frames are welded on the side walls of the tunnel, and it is grounded in accordance with established standards. It is covered with a cover plate on the top. It is usually used as a special underground passage for laying cables and is widely applied in various construction, substation, municipal, and other projects. Currently, there are three traditional forms of cable tunnel construction: brick-built cable tunnels, cast-in-place concrete cable tunnels, and prefabricated U-shaped concrete cable tunnels.
Prefabricated U-shaped concrete cable tunnels are divided into above-ground and underground types. Their main advantages include simple operation, standardized factory production, short construction periods, and the ability to minimize the adverse effects of on-site wet work and winter construction as much as possible. Among them, the above-ground prefabricated U-shaped concrete cable tunnels are located above the ground and require less capital investment. However, due to problems such as the flatness of the tunnel cover plates and the color difference of the concrete, it is not easy to control the appearance quality.
Therefore, in substation construction, underground prefabricated U-shaped concrete cable tunnels are generally used. The cable tunnels do not protrude above the ground, which makes the site flat and will not affect the aesthetics of the entire site due to the aging of the cable tunnel cover plates. However, when using underground cable tunnels, attention should be paid to dealing with the problem of water accumulation in the tunnels. Underground prefabricated cable tunnels are more suitable for areas with less rainfall.
During construction, the first step is the excavation of the foundation earthwork. The relevant construction unit needs to use mechanical equipment and then cooperate with manual trench cleaning. At this time, great attention must be paid to construction safety, ensuring both the safety of the workers and the construction progress.
After entering the construction site, the construction unit should arrange for the prefabrication of concrete components. For all kinds of materials, it is necessary to ensure that there are certificates of conformity, and the manufacturer should be required to conduct re-inspection in the laboratory designated by the construction unit. The finished prefabricated components can enter the construction site only after passing the relevant inspection and obtaining the certificate of conformity. In addition, before installation, the trench should be properly repaired and compacted.
The specific methods are as follows: ①The width of the splicing joint of the U-shaped trough must be guaranteed to be 40mm, and the splicing of adjacent "U" - shaped troughs must be smooth, with a height difference not exceeding 2mm; ②The joints of the U-shaped troughs are sealed with 1:2 cement mortar. The joints must be flat and solid, and should not protrude above the trough plate surface. After sealing the joints, there should be no cement lumps in the trough.
After the installation and joint grouting of the U-shaped trough are completed, the construction unit should backfill the earthwork on both sides of the U-shaped trough and tamp it. It should be noted that when backfilling the earthwork, pay attention to backfilling both sides at the same time to avoid the U-shaped trough from shifting or tilting.
When formulating the design plan, first of all, it is necessary to scientifically plan the power grid structure of the substation to ensure the rationality of the plan. Moreover, it is necessary to closely integrate with the overall urban planning and strengthen cooperation with various power stations to achieve the rationalization of the distribution network structure of the substation and select an installation method suitable for the "prefabricated U-shaped concrete cable tunnel". Secondly, estimate the load power of the distribution network lines of the substation and correspondingly improve the load supply level to ensure the normal operation of the power grid and ensure an adequate power supply to meet people's demand. Finally, high-quality hardware facilities for the substation cable tunnel should be selected to ensure the construction quality.
To ensure the normal use of the cable tunnel, it is necessary to strengthen the maintenance and management of the daily operation of the substation. First, use advanced detection equipment and scientific detection methods to regularly detect and inspect the commonly used equipment in the substation, summarize and submit monthly, quarterly, and annual maintenance reports, and regularly maintain the substation equipment to ensure its normal operation. Scientifically manage the substation maintenance equipment and formulate a scientific guidance plan to provide reference for the daily inspection and maintenance work of employees.
Secondly, unify the standards, improve the standardization of the cable tunnel, and use the rapidity of network information to achieve the sharing and transmission of power information resources, saving time and promoting standardization construction. Finally, improve the operation and maintenance management mode of the substation, regularly carry out fault emergency drill activities, improve the safety awareness of employees, and the maintenance command center should play a leading role. Carry out courses to enhance the safety awareness of maintenance personnel, improve their response ability, ensure the safety of power transmission, and provide high-quality services for users.
Before the project construction, to avoid construction problems, the relevant person in charge and technicians must be present when conducting the construction site survey. When carrying out on-site operations, it is necessary to comply with safety regulations, standardize the construction, and ensure the safety of protective measures. In addition, safety training should be provided to the staff, imparting skills, improving work efficiency, enhancing their safety awareness and professional quality. The construction personnel are required to strictly comply with safety regulations and construct according to the construction plan. If problems occur during the construction process, they must be reported to the management department and scientifically handled to prevent safety accidents. Once a safety accident occurs, it must be dealt with immediately, and emergency measures should be taken to minimize the impact of the accident.
First, before the formal construction, the relevant supervision unit must review the professionalism of the cable tunnel construction plan to ensure its operability. Once any abnormality is detected, the relevant construction unit should be required to correct it. In accordance with relevant industry standards, handle the review of relevant materials of the construction plan to improve the operation level and extend its operation cycle. Secondly, during the project construction, establish a professional supervision department as soon as possible, arrange special staff to go to the construction site for supervision, and reasonably standardize the construction behavior.
Actively implement the construction responsibility system, assign the work of each link to individuals, which can correspondingly enhance the sense of responsibility of the construction personnel and improve the construction quality level. Finally, after the project is completed, the relevant inspectors need to carefully carry out a comprehensive and systematic inspection work in accordance with relevant industry regulations. At the same time, invite the supervision department and technical workers to jointly carry out the acceptance work of the cable tunnel project. After the acceptance is passed, the relevant responsible person should be required to sign and confirm, and then file it to prevent the problem of shirking responsibility by future workers.
Before the construction of the cable tunnel project, the construction unit should strengthen the skill training of employees to improve their professional abilities. First, the construction unit needs to carefully review the professional level of the trainers, invite trainers with strong professional abilities and rich training experience, and provide targeted training programs according to the project requirements, so that the construction personnel can receive systematic training. After the training, test the construction employees to ensure their level and ensure the completion of the construction project of the prefabricated U-shaped concrete cable tunnel.
In conclusion, the construction quality of prefabricated U-shaped concrete cable tunnels is an important prerequisite for ensuring the safe operation of substations. Therefore, the construction unit should make scientific and reasonable planning and design, and the manager should innovate the management mode, increase the construction management intensity, pay attention to the construction quality, and ensure the safety of the construction. In addition, the relevant workers must keep pace with the times, continuously improve and enhance the installation technical level of prefabricated U-shaped concrete cable tunnels, so as to ensure the safe and efficient operation of the entire power system and strive to achieve the dual improvement of economic and social benefits.
