Conventional method of construction of an underground power house involves fabrication and erection of huge steel sections resulting in the use of significant and substantial steel in terms of tonnage. The steel sections, apart from supporting the power generators, turbines, and auxiliary equipment, the primary use is as a support for EOT cranes of the power house. The use of steel is obviously costly and adds to the project construction time.
This led us to ask ourselves “why cannot we use the available rock for this purpose?”
The answer was creation of the “rock ledge” on which the EOT crane could be supported and operated - saving cost and time.
The work needed to be done in cautious and controlled manner, as the “shape” of the ledge had to be retained while drill and blasting the rock during the making of the power house. Controlled blasting was also essential as the integrity and the strength of the rock to take the operative weights of the crane and power house equipment had to be ensured.
The success of this idea at Malana II (the rock ledge supports an EOT crane of 130 MT capacity) lead the designers and also Abir to replicate the same at Teesta III power house where the capacity of the EOT crane was 270 MT.
The idea was mooted by the designers of the project M/s Energy Infratech Private Limited. Abir rose up to the challenge.