WKA Beton Service accomplishes executions at 54 foundations in New Zealand

An ideal location on the north island is the Manawatu Gorge, a narrow canyon between the Ruahine Range and the Tararua Range. Continues winds from the tasmanien see result in outstanding earnings, yet the foundations are subject to extreme loads.

Movement measurements at the tower revealed the requirement for injections. A total of 54 turbines were inspected. 24 foundations needed injections, 10 of them even had to be shut down. All turbines needed a reliable coating.

After several meetings and building site visits in Europe the WKA Beton Service GmbH from Berlin was awarded the contract.

Influences like saltwater, subtropical climate and the permanently high dynamic strains set enormous demands on the renovation and waterproofing systems. For the injections a low viscosity, duromer resin based on epoxy was applied. This special resin is moisture compatible, fast hardening under dynamic stress and it has a highly compressive strength.

Almost 40 tons of different synthetic resin as well as equipment was shipped to New Zealand.
Long runtimes, customs formalities, earthquakes and floodings led to temporal deferrals and even more challenging conditions as initially planed. Nevertheless the shutdown turbines were back on the grid after only two weeks. Continuously excellent measurement results through external experts confirmed the success of the injections.
In order to prevent any damages to the reinforcement, some 750 drill holes were set without the usage of core drilling machines. All drillings led to the bottom flange of the insert ring in 2,27m depth. Following an extensive cleaning process all holes were inspected with endoscopes.

There will be further execution in New Zealand next year.
Restructuring measures at further WEC’s and fermenters of biogas plants in Australia, Thailand and the Philippines are in discussion.