Objective THE AIM OF THIS PROJECT IS TO OBTAIN HIGH CYCLE FATIGUE DATA WITH RELEVANT VARIABLE AMPLITUDE LOADING FOR MATERIALS USED IN WINDTURBINES IN ORDER TO OBTAIN DESIGN AND SAFETY CRITERIA. IN COOPERATION BETWEEN THE DLR, ECN, AND NLR BY SUBCONTRACT A THREE-YEARS RESEARCH PROGRAMME IS SETTLED FOR THE FATIGUE TESTING OF SEVERAL WINDTURBINE MATERIALS AND SUBSTRUCTURES. AT ECN AN EXPERIMENTAL PROGRAMME IS CARRIED OUT TO INVESTIGATE THE EFFECT OF PRE-LOADING (HIGH-LOW STEP TESTS) ON THE CONSTANT AMPLITUDE FATIGUE PERFORMANCE OF GLASSFIBRE/POLYESTER COUPONS FOR TWO STRESS RATIOS, I.E. R=0.1 AND R=-1. THE STIFFNESS DEGRADATION IS MONITORED ON-LINE. THE RESULTS SHOW CONTRARY TO THE EXPECTATION, NOT THE DETRIMENTAL EFFECT ON THE C.A. FATIGUE LIFE AT R=0.1 HOWEVER, AT R=-1, THE C.A. FATIGUE LIFE IS REDUCED IN THE HIGHER STRESS RANGE. THE PRELIMINARY RESULTS OF SOME TESTS CARRIED OUT WITH THE WISPER LOAD SEQUENCE INDICATE, THAT THE EXPERIMENTAL FATIGUE LIFE IS LARGER THAN PREDICTED BY MINER'S RULE. IN A SIMILAR MANNER THE NLR HAS STARTED NOW CONSTANT AND VARIABLE AMPLITUDE TESTING OF FILAMENT WOUNT GLASSFIBRE/POLYESTER IN COOPERATION WITH RISOE (DK) AND RUG (B). FIRST RESULTS ARE SHOWN ON MATERIAL WITH A +/- 10 DEGREE C. LAY-UP. TESTING WAS DONE AT A R-RATIO R=10. THE AIM OF THE DLR PROJECT IS TO OBTAIN FATIGUE DATA OF GLAS-EPOXY (GI-EP) MATERIAL FOR ROTORBLADES AND TO SHOW THE LIMITS OF THE CERTIFICATION ALLOWABLE. FOR THIS PURPOSE THE PROGRAMME IS CARRIED OUT DOUBLETRACKED. THE TESTS ARE CARRIED OUT ON SMALL SPECIMENS AND ON STRUCTURAL BLADE COMPONENTS. THE FATIGUE BEHAVIOUR UP TO 10/8 LOAD CYCLES IS INVESTIGATED WITH CONSTANT AMPLITUDE. ADDITIONALLY, LOAD SEQUENCE TESTS WITH IEA-STANDARD WISPER WILL TAKE PLACE. THIS INCLUDES TIME INTENSIVE TESTS. THEREFORE, A SIMULTANEOUSLY WORKING TRIPLE CLAMPING DEVICE (TCD) FOR SPECIMENS AND A TRIPLE TESTING RIG (TTR) FOR THREE BLADE COMPONENTS WERE DEVELOPED. THE E - N CURVE FOR THE GI-EP COUPON SPECIMENS HAS A STACKING SEQUENCE OF (+/_ 45 DEGREES C. G1 / 0 DEGREES C. G1,5) SYM AND A STRESS RATIO OF R=-1. AT THE SPAR BEAMS STRAINS, DEFLECTION AND TORSION ARE MONITORED BEFORE AND AFTER DYNAMIC LOADINGS. AS A FURTHER INSPECTION METHOD THE DAMPING BEHAVIOUR IS BEING INVESTIGATED. Fields of science engineering and technologyenvironmental engineeringenergy and fuelsrenewable energywind power Programme(s) FP1-ENNONUC 3C - Research and development programme (EEC) in the field of Non-Nuclear Energy, 1985-1988 Topic(s) Data not available Call for proposal Data not available Funding Scheme CSC - Cost-sharing contracts Coordinator GERMAN AEROSPACE CENTRE EU contribution No data Address Linder Höhe 51147 KOELN Germany See on map Links Website Opens in new window Total cost No data Participants (3) Sort alphabetically Sort by EU Contribution Expand all Collapse all FA Germany EU contribution No data Address München See on map Total cost No data NATIONAL AEROSPACE LAB. (NLR) Netherlands EU contribution No data Address AMSTERDAM See on map Total cost No data Netherlands Energy Research Foundation Ecn Netherlands EU contribution No data Address 1755 ZG Petten See on map Total cost No data