| Work Detail |
The foundation and installation specialist, IQIP, has put their newly developed piling technique EQ-Piling in action, which the Dutch company claims allows for the noise-compliant installation of even the largest monopiles.
Conventional impact piling is an established method for installing large monopile foundations at the required depths, but it generates noise that can be harmful to marine life, said the company with headquarters in Sliedrecht, the Netherlands.
According to IQIP, the challenge they faced was to achieve the required force to overcome soil resistance while reducing noise levels. EQ-Piling is said to meet this challenge by employing a newly developed technique featuring a prolonged impact force characteristic.
The method utilises a large water tank as a drop weight. The tank, containing up to 1,700 tonnes of seawater, is raised by hydraulic cylinders and released from the drop height setpoint.
The water tank falls onto buffer cylinders which transmit the impact force to the pile, dampening it to extend the impact time. The impact time is 15-20 times longer than that of conventional piling, resulting in a smooth energy transfer to the monopile and reduced noise levels, said the Dutch company.Unlike conventional methods that rely on impact force, EQ-Piling generates a pushing force. The technology ensures that developers, governments, and contractors can now work in full compliance with environmental regulations, according to the company.
Pile fatigue is reduced by up to 90 per cent, allowing the pre-installation of secondary steel fixings.
Reduced or eliminated noise mitigation measures can lower the foundation and installation project costs, decrease risks such as project interruptions, and cut CO2 emissions and energy consumption by reducing the need for vessels, IQIP added.
In July, Heerema Marine Contractors demonstrated a noise reduction of 24 decibels (dB) during installation work at EnBW’s He Dreiht offshore wind farm in Germany, where the offshore construction specialist employed a noise mitigation spread with equipment supplied by IQIP. |
