11) “RCC- The Remarkable Construction Technology“

Roller Compacted Concrete (RCC) is of great importance due to its advanced procedures which have been used for the past 25 years all over the world, as frequently being the most economical way to build safe dams. Concrete is the second largest material consumed by human beings after food and water as per WHO.

RCC continues to gain recognition as a competitive material for building new and rehabilitating existing dams. RCC had been touted in engineering journals during the 1970s as a revolutionary material suitable for, among other things, dam construction.  RCC has three key properties that make it uniquely suited for dams: economy, performance, and high-speed construction. American Concrete Institute (ACI) 207.5R-89 defines Roller Compacted Concrete (RCC) as concrete compacted by roller compaction.

In the quarter century since Willow Creek Dam, considerable research and experimentation have yielded innumerable improvements in concrete mix designs, dam designs and construction methods for roller-compacted concrete dams. Currently the highest dam of this type is Longtan Dam in China, at 216 m, with Diamer Basha Dam in Pakistan planned at 272 m. The repair of the collapsed intake tunnel of Tarbela Dam proved that the material had more adequate strength and durability.

The Water and Power Development Authority of Pakistan (WAPDA) intends to build number of new dams, hydropower projects in near future, those are based on Roller Compacted Concrete (RCC) Technology, a new field in Pakistan. WAPDA is interested to develop this in- house expertise for Diamer Basha Dam and other upcoming major RCC dam projects.

Central Material Testing Laboratory (CMTL), WAPDA is capable for carrying out testing activities in the field of Soil Mechanics, Concrete Section, Rock Mechanics, and Chemical Section. For the refurbishment and up-gradation of existing laboratory, WAPDA is trying to establish the testing facilities for Roller Compacted Concrete (RCC) with the same confidence and precision as typically done by internationally recognized authorities such as the U. S. Army Corps of Engineers and U.S. Bureau of Reclamation.

Diamer Bhasha dam with a height of 272 meters, cost of the US$ 13.684 billion dollar would generate 4500 MW electricity and store over 8.1 Million Acre Feet of water to meet country’s growing power and irrigation needs is being built on Indus river, about 315 kilometers upstream of Tarbela Dam. This world’s highest concrete dam on River Indus would produce 19 billion units of electricity annually and enhance life of Tarbela Dam by over 35 years.

Roller compacted concrete (RCC) is an accepted method of constructing new and rehabilitating old dams. Dam safety modifications must be conducted rapidly to minimize disruption of reservoir operations and exposure to dam failure during construction. Depending on the complexity of the structure, RCC costs 25 to 50% less than conventional concrete. RCC can be placed in a short time frame, allowing the dam to resume normal operations quickly. This concrete methodology is economical because it can generate high-volume, high-speed construction and this is the main reason for designers to select RCC for new dam construction.

Sara Shahid
Civil Engineer

Write Articles for civilengineerspk.com

Remarkable Construction Technology, Remarkable Construction Technology, Remarkable Construction Technology, Remarkable Construction Technology, Remarkable Construction Technology, Remarkable Construction Technology, Remarkable Construction Technology, Remarkable Construction Technology, Remarkable Construction Technology, Remarkable Construction Technology, Remarkable Construction Technology, Remarkable Construction Technology