Research On Mechanical Performance Of Steel-concrete Composite Structure For Wind Turbine Tower

As people gradually pay attention to wind energy, wind power has developed rapidly. Therefore, wind turbine unit capacity is increasing rapidly, which will lead to height, wall thickness and the diameter of traditional steel frame increase greatly, bring difficulties to the tower of manufacturing, installation and transportation, the cost has increased dramatically. However, concrete-filled double skin steel tube has the same good mechanical performance of traditional solid concrete-filled steel tube, but also has advantages of relatively high stiffness, small deadweight and high economic efficiency. In order to reduce the large capacity wind turbine tower construction cost, people is going to study and pay attention to new structure. On the basis of the wind turbine tower research status and concrete-filled double skin steel tube advantages, this paper provided new steel-concrete composite structure for wind turbine tower which based on concrete-filled double skin steel tube, and designed the structure. Through experiments and numerical simulation studies, obtained steel-concrete composite structures working mechanism and a reasonable structure design.This paper designed 5 types of steel-concrete composite structures for wind turbine tower based on concrete-filled double skin steel tube, the difference between 5 types of structure is different arrangements of ribs inside and outside the steel tubes’ surfaces contact with concrete. Through the axial compression test of all kinds of specimens, deformation and destruction form of steel tubes, the relation between axial load and strain and the influence of ribs arranged in different ways on the specimen bearing capacity are investigated. From the test results, full-length ribs welded on the inner and outer tubes improved the deformation and compressive stiffness and bearing capacity of specimens. As used herein, ABAQUS finite element software simulated the axial compression tests of 5 types of specimen. Compared the calculation and test results, and then verified the validity of the finite element model. The contrast study on the entire load process of 5 types of specimen from compression stiffness, ductility characteristics and working mechanism of internal and external steel tube aspects obtained from the finite element calculation results. At the same time, through the stress distribution at the feature points in the load process analyzed the reason of deformation and destruction form of specimens in the test process, which verified the full-length rib alleviate or avoid steel tube early into the yield stage, and prevented the specimens destroyed by steel tube partial buckling.Finally, the contrast analysis of comprehensive performance of 5 types of specimen combined with the bearing capacity, compressive stiffness and ductility characteristics. Compared to the layered rib, full-length is more applicable in steel-concrete composite structure for wind turbine tower, and draw some conclusions for practical engineering design reference. Reasonable structure is based on the manufacturing cost, installation and transportation to further optimize.