Rate of penetration prediction for large-diameter offshore drilling for wind farm structures

It is essential to shift towards sustainable energy in a world with increased awareness of global warming and climate change. There is an anticipated increase in offshore wind farms in the upcoming years. There is a need to explore new locations in tougher soil conditions for the wind farm developments as the sweet spots or technically easy spots have been taken. The rock strength must be overcome in the new locations of concern. Due to pile buckling the conventional pile driving technique becomes an undesirable solution. An alternative method that can complete wind farm infrastructure efficiently in challenging soil and rocks is drilling. In addition, there are some regions where pile driving becomes unviable due to the rules associated with maximum noise levels. The cost of the project increases significantly in the case of the use of noise mitigation measurements. Again, drilling can be considered as an alternative solution, because as a result, the noise generated during installation decreases significantly. The important role in the total drilling process is the drilling phase itself, and it can easily be equal to more than half of the total pile installation time. It is necessary to have a very decent prediction of the drilling rate for the installation of a large number of foundation piles, especially since it is important to have this information during the tender phase of a project. The currently available drilling rate models are based on empirical evidence and tend to be specific to certain drilling methods in each type of rock. This study aims to better predict the drilling rate which will be applicable for different amounts of large-diameter drilling for various rock and soil types. Significant importance will be given to the analysis of conventional top-hole drilling performance. Investigation of top hole and deep hole drilling bit design will be conducted and its applicability to soil drilling for windfarm installation will be tested.