Research into novel hybrid joining concepts for segmented composite blades aims to inform the development of modular wind turbine technologies, supporting the industry’s pursuit of larger, more efficient blade design solutions.
As offshore wind turbines grow larger to improve energy capture, the design of wind turbine blades faces mounting challenges. Blade lengths now exceed 100 meters, especially in offshore applications, enhancing energy capture but complicating manufacturing, transport, and assembly. Traditional full-length blade construction is costly and logistically demanding, prompting the industry to explore modular blade designs.
Segmentation of blades, particularly spanwise segmentation i.e. splitting the blade into manageable-sized sections along its length—has emerged as a promising solution to mitigate these challenges. However, re-joining split blade sections while preserving structural integrity and performance comparable to a monolithic blade remains a significant engineering challenge. Existing solutions like mechanical fastening or adhesive bonding offer partial relief but are hindered by trade-offs such as added weight or complex assembly procedures.
To address this challenge, a research team based at the Bristol Composites Institute, University of Bristol, has developed a hybrid adhesive snap-fit joint concept tailored for wind turbine blades. This novel design integrates the alignment and retention features of snap-fit mechanisms with the smooth load transfer capability of adhesive bonding. The resulting joint design is lightweight, scalable, and easier to assemble on site, offering a compelling alternative to conventional joining methods.
This innovative hybrid joint is designed in such a way that the joint components are embedded into the critical load-bearing spar cap region of the blade, where it redirects load paths through the snap-fit joint features while preserving the aerofoil’s outer geometry. Maintaining the external blade profile allows the joint to be incorporated without compromising aerodynamic performance or requiring major design alterations to existing blade moulds, thereby supporting backward compatibility with current manufacturing processes.
Advanced finite element analysis (FEA), incorporating anisotropic composite material models and failure criteria, has demonstrated the joint’s ability to handle extreme load conditions representative of a 10 MW reference blade. The results showed that the joint can sustain design loads without material failure all while introducing less than 1% additional weight compared to a monolithic blade, representing a significant improvement over conventional joining methods. While further investigation is needed, including prototype building and fatigue loading evaluation, this study represents a significant step toward scalable and manufacturable joint solutions for modular wind turbine blades.
Further Information:
The hybrid adhesive snap-fit concept has broader relevance and could inform future joining strategies for composite structures across other engineering applications. Realising its full potential, including prototype development, will require collaborative efforts, and the research team welcomes engagement from industry and academic partners interested in advancing this work toward practical implementation.
Research Team:
Muhammad Basit Ansari, Dr Vincent Maes, Dr Terence Macquart, Dr Eric Kim, Dr Alberto Pirrera To learn more or explore collaboration opportunities, please contact
Muhammad Basit Ansari