Preparation and properties of lightweight, high-strength, and low-shrinkage ECC materials for new steel bridge deck composite pavement

作者：Wei Xie, Yanwei Fang, Wei Xu, Jinhui Li, Fang Xu, Tusheng He, Jun Wang, Hao Yan, Zi Yu, Qingjun Ding, Wei Du, Leheng Li · 发表于：Case Studies in Construction Materials · 年份：2025 · DOI：10.1016/j.cscm.2025.e05200 · 被引用次数：2 · 研究领域：Innovative concrete reinforcement materials、Concrete and Cement Materials Research、Concrete Properties and Behavior

To address the challenges of conventional cement concrete pavement materials for orthotropic steel-concrete composite bridge decks, including high self-weight, low tensile deformation capacity, high brittleness, and susceptibility to cracking, all of which adversely affect their service life, a novel lightweight, high-strength, high-toughness, and low-shrinkage Engineered Cementitious Composite (ECC) material has been developed. This advancement was achieved through three strategies: 1) the incorporation of calcium carbonate whiskers for microstructural enhancement, 2) hybrid reinforcement using organic fibers and steel fibers for toughening, and 3) the synergistic application of expansion agents paired with internal curing aggregates for shrinkage reduction. The mechanisms underlying the performance enhancement of this ECC material were investigated through low-field nuclear magnetic resonance and scanning electron microscopy. Furthermore, a new composite pavement structural system for steel bridge decks based on the developed ECC was proposed. The results indicate that, Compared to PE fibers, steel fibers have a lesser impact on the workability of ECC materials but significantly improve their strength, toughness, and crack propagation control. A hybrid mix of 1 vol% PE fibers and 0.5 vol% SF provides optimal performance. Substituting fly ash cenospheres (FAC) with ceramic sand as fine aggregate increases the apparent density and compressive strength of the ECC material. The...