Sleek towers replace conventional HT lines

Vadodara: Sleek, lean and cost-effective transmission towers are replacing overhead extra high tension (EHT) lines in Gujarat to make way for the Mumbai-Ahmedabad High Speed Rail (MAHSR) Corridor popularly known as bullet train project.
According to officials of the National High Speed Rail Corporation Limited (NHSRCL), which is implementing the bullet train project, more than one-third of relocation work and 80% of foundation work, for the electrical transmission lines have already been completed.
NHSRCL is relocating more than 1,600 electrical transmission lines out of which 164 are overhead EHT lines that are infringing with the MAHSR in Gujarat from where around 75% of alignment will pass through.
The challenge before the engineers was the height of the transmission lines which is usually in the range of 6-9 m from ground level. In the case of national highway crossings, it is in the range of 8-11 m and for railway crossings it is 14-19 m.
But since the bullet train itself will run at a height of 8-12 m from ground level, the transmission lines crossing the corridor are required to be raised at a height of more than 30 m.
“To accommodate the height of towers and sustain weight, a broader foundation is required,” said an NHSRCL official.
After a lot of brainstorming, engineers from NHSRCL and the Gujarat Energy Transmission Corporation Limited (GETCO) improvised the design of the towers.
“Special narrow base tower design has been adopted which requires 80% less land for tower foundations. This has reduced requirement of concrete to one-third and steel reinforcement by one-sixth without compromising on safety and strength of the lines,” the official said.