This time we are taking a visit to Odisha, one of the 29 states of India, located in the east of the country. Odisha has 485 km of coastline along the Bay of Bengal on its east, from Balasore to Malkangiri. It is the 9th largest state by area, and the 11th largest by population. Odia is the official and most widely-spoken language, with 33.2 million speakers.
The heavy industries of India
On August 15, 1947, India earned its independence. The baby steps towards achieving modernization and attaining infrastructural development for the young country led to the establishment of several heavy industries. Foremost among those were Rourkela Steel Plant (RSP), in Sambalpur District, Odisha. It was the first integrated public sector steel plant in the whole of India and was set up in collaboration with the former West Germany.
First plant in Asia with energy-efficient steelmaking process
The RSP, presently controlled by the Steel Authority of India (SAIL), produces a wide variety of special purpose steels, and has many firsts to its credit. In fact, it was the first plant in Asia to adopt the energy-efficient LD steelmaking process.
Versatile steel usage
Diverse RSP products are used in a variety of industrial applications, including the manufacture of LPG cylinders, automobiles, railway wagon chassis, silicon steels for the power sector, high quality pipes for the oil and gas sector, tin plates for the packaging industry and specialty steels for the defense sector among others.
The dam brings water to the plant
To cater for the water needs of this mammoth plant, Mandira dam was conceived and constructed by Hirakud Project Authority during the years 1957–59. The dam was built across Sankh River, a tributary of Brahmani River. The dam is located at a distance of 32 km from Rourkela, and the RSP plant is about 24 km downstream of it. It has a 426.72 m zoned embankment and releases a regulated supply of water of 100 cusecs through an 8 x 8 foot outlet sluice. It also has a weir (low dam) built across Brahmani river near Rourkela to pump out water from the pond to the plant area.
Structural damage of the dam had to be repaired
Over the past half century, the dam has suffered severe structural damage due to natural wear and tear, requiring intensive repair and retrofitting. Under closer scrutiny, it was found that the dam’s aprons, spillway, blocks and buckets had been acutely damaged. There were instances of massive pitting erosion and also cavity formation. While ensuring that operations continued running smoothly at RSP, renovation work on the dam began immediately as a matter of utmost priority.
Quality tests at the site
Sika products were used for the renovation works following approval by the Central Water and Power Research Station (CWPRS) in Pune, a renowned research institute under the Indian government’s Ministry of Water Resources. The products were subjected to a number of quality tests at the site, such as pot life, compressive strength, bond strength, shrinkage strength, abrasion test, and tensile
Getting it fixed again
The massive cavities created in the spillways were filled up using SikaTop®-122. It was lined with Sikadur®-31 primer and Sikadur®-41 up to 5 mm. Finally, two layers of epoxy coating Sikagard®-63/1 were applied to obtain a smooth surface. Next in line was the treatment for the cavities occurring in the chute, baffle block and weir walls. The walls and blocks were jacketed up to 75 mm using SikaRep® Microcrete-2 and further lined with Sikadur®-31 mortar primer and Sikadur®-41 mortar up to 5 mm. Here as well, two final coats of epoxy coating Sikagard®-63/1 were applied to achieve a smooth surface.
Cracks were treated with surface injections
The basin area had already been repaired with new concrete. However, to enhance the life of the concrete many times over, it was lined with Sikadur®-31 along with two final layers of Sikagard® epoxy coating. The cracks and voids found all over the dam were treated with surface injection using low viscosity injection epoxy resin, i.e. Sikadur®-52, whereas the construction and expansion joints were repaired employing the Sikadur - Combiflex® SG Tape System.
Total restauration completed
The Mandira dam has been completely restored to its former glory, preparing the way for RSP to reach new highs. And no wonder that RSP, which came on stream in the 1960s with an installed capacity of only 1 million tonnes per year, is now expected to increase that to an enormous 10.8 MTPA by 2025.