WKA Beton Service GmbH protected 43 foundations in Taiwan

Therefore the west coast of the west pacific island is an ideal site for wind power plants. Due to the location of the island at the western edge of the Pacific Ring of Fire, a number of earthquakes happen to occur each year. Consistently appearing typhoons and rainy monsoons require a reliable long-term foundation protection.

Movement measurements of some of the towers revealed that special resin injections were necessary in order to stabilize the insert ring. The specialized WKA Concrete Service GmbH from Berlin with references in more than 20 countries was awarded the contract. Waterproofing and injections had to be done at 43 turbines at Taiwan’s west coast. The applied restoration and waterproofing systems had to meet enormous requirements such as subtropical climate, saltwater, and the dynamic stress due to permanently high wind speed.

For the injections a low-viscosity, duromer resin based on epoxy was applied. It is not only humidity-resistant and fast hardening under under dynamic stress, it also has a highly compressive strength.

More than 200 holes up to 1,25m depth were drilled without the usage of core drilling machines and therefore without destroying the reinforcement. Basis for a successful injection was also an endoscopy of all drilled holes. Electric and pneumatic driven diaphragm pumps were used during the pressing process. For the foundation sealing and the permanently elastic waterproofing of the joint between concrete and insert ring, a fleece-reinforced Polymethylmethacrylate (PMMA) was applied.

This system has specifically been developed for the application on wind turbines. The PMMA-material stays permanently elastic even at highest and lowest temperatures, which is also certified by the European technical approval. Further characteristics are e.g. salt water resistance, consistency against chemicals, UV and infrared rays. The resistance against hydrolysis, roots and rhizomes are additional important features for the application on wind turbines.

The WKA Beton Service GmbH has applied this system on more than 2500 turbines on two continents, including extreme locations such as the arctic circle, various coastal sites e.g. Orkney Islands, Aland Islands and Hybridean Islands as well as hot regions e.g. the Mediterranean area or Andalusia.

Trade show talks in Thailand and Vietnam as well as the recently acquired knowledge in Taiwan suggest that there is more to be done in south east Asia. The next restorations, injections and waterproofings will take place in Austria, Sweden, Italy and Scotland.

Visit us at the WindEnergy 2014 in Hamburg (Hall A1, Booth Nr. 537)