The long term reliability of tidal turbines is critical if these structures are to be cost-effective. Optimized design requires a combination of material durability models and structural analyses which must be based on realistic loading conditions. This paper presents results from a series of flume tank measurements on strain gauged scaled turbine blades, aimed at studying these conditions. A detailed series of tests on a 3-blade horizontal axis turbine with 400 mm long blades is presented. The influence of both current and wave-current interactions on measured strains is studied. These tests show that wave-current interactions can cause large additional loading amplitudes compared to currents alone, which must be considered in the fatigue analysis of these systems. Highlights ► This is one of the first papers to describe how wave and current conditions affect tidal turbine blade deformation. ► There are also very few published data from devices at sea so these results are very important. ► Results from flume tank tests are presented first, showing how blade deformation depends on current speed. ► Then results indicate that the wave currents combination will significantly enhance blade loads compared to currents alone.

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractSynthetic fiber ropes are now being used in mooring systems off Brazil and in the Gulf of Mexico, and are being considered for deepwater handling applications. Their behavior under tension loads is well understood but induced torsion effects have received less attention. This paper presents tests to measure induced torque in full size steel, aramid and polyester wire ropes. Results are compared with model predictions and good correlation is obtained. A specially designed torque matched 500 ton break load polyester rope is tested and shown to enable steel wire rope to be used in series with polyester without inducing twist in the system.

For the last few years there is a more and more pressing need to develop system for detecting HAB at their early stage. Researchers have then been working on new in situ sensor. In this paper a submarine transducer based on surface plasmon resonance is reported. It demonstrated a refractive index resolution of 3.10 -6 , which is promising for later phytoplankton detection.