Compression-related performance of a structural concrete produced with crushed wind-turbine blade

Abstract

The sustainability of the concrete industry is an important issue worldwide. The need for concrete increases steadily, and the natural-resource exploitation and cement manufacturing are speeding up climate change and global warming, among others. The wind-energy sector is also facing sustainability issues, as some of the first-installed wind-turbine blades are approaching the end of their approximately twenty-year life span and need to be replaced. These two different fields can help each other by adding crushed wind-turbine blade to concrete, so a second life for the crushed wind-turbine blades can be found, thus also reducing the use of cement, which is the concrete´s most polluting raw material. This study aims to find out whether the addition of crushed wind-turbine blade is valid for structural use up to 6% vol., in steps of 1.5% vol. Hence, five different mixtures were made incorporating this alternative material as an addition and maintaining constant the aggregate and cement content. Occluded-air content, compressive strength, modulus of elasticity and Poisson´s coefficient have all been evaluated. This analysis demonstrates that the higher the crushed-blade content, the higher the occluded air, although it did not result in a notable loss of the compression-related mechanical properties when added in small percentages. Nevertheless, when the percentage of crushed wind-turbine blade was increased, these properties decreased their values, yet still largely maintaining their suitability for structural usage. The results yield that the addition of crushed wind-turbine blade to concrete fulfills the requirements for be used in structural applications becoming a plausible solution to the raising sustainability issue of the concrete-manufacturing industry and the wind-farming sector.