Wind Towers: Reaching for the Sky with Ductal® UHPC

12.13.2017

Ames, Iowa, USA

 

One of the fastest growing sources of energy

Wind power is one of the fastest growing sources of energy in the world. In the US alone, wind power has attracted more than $100 billion in private investment since 2008. In addition to the economic upside including creation of thousands of new jobs - there are many important environmental benefits, such as significant reductions to: greenhouse gas emissions; air pollutants; water consumption and withdrawals and; major carbon dioxide (about 125 million metric tons)1.

At Iowa State University (ISU), a research team led by Dr. Sri Sritharan (professor of civil, construction and environmental engineering) recently completed an 18-month, $1 million study of concrete technology for tall wind turbine towers (nearly twice as tall as current wind towers). LafargeHolcim was an "In-Kind" partner on this innovative project. Dr. Sritharan says that the "tall towers can add more capacity for renewable energy in all states across the nation".2

Hexcrete: the new concrete tower made with Ductal® UHPC

To achieve such unprecedented heights, he has been leading the development of a new concrete tower technology called "Hexcrete", assembled from precast panels and columns made with high-strength concrete or LafargeHolcim's ultra-high performance concrete (UHPC) called Ductal®. Hexcrete can also be combined with steel tubular technology to create hybrid wind turbine towers.

Hexcrete made with Ductal®
Hexcrete cells can be assembled on site and a crane can stack them up to 140m high. Image courtesy of Sri Sritharan.

Extensive lab tests conducted by the ISU team have demonstrated that the technology will work and economic studies indicate that the technology can be cost competitive 2, presenting a strong case for the future global construction of taller, extremely durable wind towers made with Ductal® UHPC!

  • The first UHPC (Ductal®) bridge in the US was built in Iowa. ISU, together with the Federal Highway Administration (FHWA), has been a valuable collaborator in the development, prototyping, testing and validation of various Ductal® bridge applications for about two decades. 

  • Our concrete and cement solutions have been used to erect wind farms in Canada, Brazil and Romania (the largest wind farm in Europe, supplying 400,000 households with clean energy)3 . Last year, LafargeHolcim SA and the Brazilian construction company and tower supplier, Dois A Tower System (DTS), Advanced Tower Systems (ATS), signed a memorandum of understanding to launch a new technology for manufacturing UHPC wind towers for the Brazilian market4.