State Grid Xuzhou Power Supply Company: Utilizing prefabricated cable ducts for line renovation project

At the site of the Langshan–Dongshan 110 kV line renovation project, construction personnel from State Grid Xuzhou Power Supply Company directed hoisting equipment to successfully complete the installation of prefabricated cable ducts. From hoisting to assembly, the installation process for a single cable trench required only two steps and took less than three hours. It is the first line renovation project in Xuzhou to employ prefabricated cable ducts.

Prefabricated cable ducts are cast and manufactured at the production facility. After on-site workers finish excavating base trenches and pouring cushion layers, the preformed duct modules are transported to the site for assembly and installation. They are then connected and secured section by section using connectors. The entire construction process is as simple and efficient as "building blocks," allowing for incremental installation and backfilling and significantly improving construction efficiency.

The Langshan-Dongshan 110 kV line renovation project involves the construction of nearly 4 kilometers of new 110 kV lines. This includes approximately 1 kilometer of double-circuit overhead lines and about 2.48 kilometers of double-circuit cable lines. In traditional cable laying methods, the process of casting duct banks on-site involves intricate and labor-intensive steps. These include formwork installation, rebar binding, concrete pouring, and extended curing periods. This approach not only demands substantial labor and resources, but is also highly susceptible to adverse weather conditions such as rain and strong winds. These factors often lead to issues like cracking and inadequate structural strength.

"Compared to traditional construction methods, prefabricated ducts can reduce the on-site workload and waiting time by over 40 percent," said Li Qi, director of the Development and Construction Center at State Grid Xuzhou Jiawang Power Supply Company. He also emphasized that the integrated casting technology provides prefabricated cable ducts with stronger load-bearing capacity, making them better suited to complex underground environments. They effectively address issues such as high ground settlement pressure.