Abstract:

To tackle the disposal dilemma of decommissioned wind turbine blades and explore their potential for high-value utilization in construction materials， this study comparatively analyzed the effects of recycled wind turbine blade fibers （RWTBF） and glass fibers at different dosages （0.5%， 1.0%， and 1.5%， mass fraction） on the hydration process of Portland cement. The research focused on the effects of these two fiber types on the mechanical properties and microstructure of the cement matrix. The results indicate that the incorporation of both fibers prolongs the initial and final setting time of the cement， exerting a slight retarding effect on the early hydration process. Regarding mechanical performance， RWTBF demonstrates a more pronounced reinforcing effect. At 28 d， the specimens with 1.5% RWTBF achieve a peak flexural strength of 11.7 MPa， significantly outperforming the 8.8 MPa of the control group and the 9.4 MPa of the equivalent glass fiber group. Concurrently， compared to the baseline compressive strength of 68.7 MPa for the control group， the compressive strength of the 1.5% RWTBF group increases to 71.4 MPa， while that of the equivalent glass fiber group rises to 70.9 MPa. Microstructural analysis reveals that， compared to glass fibers， RWTBF constructs a more effective network structure within the cement matrix， thereby substantially enhancing the flexural strength of the paste. In conclusion， the application of RWTBF in cementitious materials not only effectively improves material performance but also provides a viable pathway for the high-value recycling of wind energy waste.

Key words: Portland cement, recycled wind turbine blade fiber, glass fiber, hydration product, mechanical property, microstructure