In recent years, the international demand to produce green energy has been growing to address the issues of energy security and climate change. To date, wind technology has presented most maturity due to high availability of wind resources. Erecting wind turbines offshore, however, presents significant new engineering challenges. Offshore foundations for these energy converters must be able to resist large overturning moments as well as numerous cycles of lateral loading caused by waves and wind. Thus, the need for an efficient cost-effective foundation to support the turbines is becoming more important. In this paper, a specific design of a gravity base foundation system developed for offshore wind turbines is considered. The foundation is a conical hollow concrete gravity type structure which rests on the seabed and utilises its self-weight to support the turbine. A scale-model of the proposed foundation has been experimentally tested at the University College Dublin (UCD) test site in Blessington, Ireland. The structure’s performance has been analysed under a range of supporting conditions from the absence of pile foundations to the incorporation of piles. This paper presents the findings of this research.@en

Vibration-based Structural Health Monitoring (SHM) is an area of ongoing research and has received much attention from researchers in recent years. Online damage detection methods for bridges rely on placing sensors on the structure to detect anomalies in measured parameters such as acceleration, frequency or displacement among others. Changes in these parameters can be used to infer the presence of damage such as cracking in bridge beams, foundation scour etc. These methods mostly rely on using the signals arising on a bridge from ambient traffic or environmental loading. For foundation scour detection purposes, the lateral response of a bridge is of particular interest in that this has been shown to be particularly sensitive to the scour phenomenon. Vehicle-Bridge Interaction (VBI) effects can have a significant influence on the condition of output vibrations from a bridge element. In this paper, the effect of vehicle travelling velocity on the lateral response of a typical highway two-span integral bridge is investigated. It is shown that depending on the velocity of the vehicle relative to the oscillatory period of the bridge it traverses, the bridge’s dynamic response is either amplified or diminished by varying degrees. This phenomenon could influence the accuracy of a particular damage detection method relying on output system vibrations to infer damage.@en