Challenges and Opportunities in Scaling Eco-Friendly Ultra-High-Performance Concrete with Hybrid Fibers: A Bibliometric and Technical ReviewChristo George, Suriya N, Somdutta, Abhishek Kumar, Alok Pandey and George Uwadiegwu AlanemeE3S Web Conf., 702 (2026) 01022DOI: https://doi.org/10.1051/e3sconf/202670201022