The Need to Integrate Geophysical With Geotechnical Data to Aid Pile Design And Installation: A Case Study of the Sheringham Shoal Offshore Wind Farm

Birchall, R. (Gardline Geosurvey)

OnePetro 

Abstract:

Geotechnical and geophysical investigations have to be combined. It is further suggested that when considering existing guidelines, emphasis should be placed on bringing groups of professionals from different fields together to further understand geological settings and avoid costly mistakes. This project is an example of an integrated approach to survey design and interpretation. The data was gathered and fed back into the interpretation, eliminating much of the uncertainty and refining the model to mitigate the risks to the level required for pile design and installation. Geophysical data and borehole information should be tied together and to show how relying purely on one set of data could have potentially expensive consequences. For this project, combining the datasets provided further understanding of the geological model, allowed for refining of the model, and when combined with expert knowledge and planning, enabled long-term savings to be made.



1. Introduction

There are currently no recognised guidelines for conducting site investigations for renewable projects similar to those that are used for the installation of oil and gas related infrastructure. UK Offshore Oil and Gas Industry Association (UKOOA) guidelines are considered out of date and have now been superseded by the new International Association of Oil & Gas Producers (OGP) guidelines (OGP, 2011). The Offshore Site Investigation and Geotechnics Group from the Society of Underwater Technology (SUT) prepared guidance notes on site investigations for offshore renewable energy projects (OSIG, 2005) but these have yet to be finalised. Planning and integration of the site survey from an early stage by suitably experienced professionals will save operators significant resources. The main issue is the tight deadlines to which the developers work and the operator’s expectations of when the data and results can be presented. Sheringham Shoal wind farm is scheduled to come online in the summer of 2012.