Contribuição ao projeto de fundações superficiais de aerogeradores assentes nas areias de dunas do litoral cearense

Abstract

This paper assesses the design methodologies for shallow foundations of wind generators founded in sand dunes. It derives its data from the study of a case history located in the sea front area of the Ceará State. The described research initially characterized the local wind regime, with subsequent analyses of structural instrumentation at field and small scale tests in wind tunnel. The soil at foundation level was fully characterized in laboratory by general geotechnical tests, together with oedometric and direct shear ones. Standard penetration tests were carried out on site, with energy and torque measurements, besides prebored pressuremeter tests. The foundation loads from the studied wind generator were estimated and compared by distinct theoretical approaches. Methodologies to derive the foundation´s vibration were also employed and compared. The obtained range of variation of the foundation´s vibration frequency was large, but without any resonance. It was also noticed that the decrease of the maximum operation velocity of the wind generator would allow for a considerable reduction on the foundation costs.