This study addresses the intrinsic effect of hybrid fibres 3D network on the electrochemical characteristics of Ultra-High Performance Fibre Reinforced Composites (UHPFRC), including experimental investigations and mechanism analysis. Firstly, the matrix of the UHPFRC is fabricated based on the modified Andreasen & Andersen model. Then, three types of fibres (long steel fibre (LSF), short steel fibre (SSF) and polyvinyl alcohol fibre (PVA)) are further incorporated into the developed UHPFRC to generate different hybrid fibres 3D network. After that, the mechanical properties, chloride permeability and electrochemical properties of the designed UHPFRC with hybrid fibres are analyzed. The obtained results exhibit that with an increase of PVA content, the steel fibre network can be significantly disturbed, and the capacity of designed UHPFRC almost decrease linearly. In contrast, the added SSF cause that the capacity of UHPFRC with hybrid will decrease firstly and then increase. This implies that there is a balance point for the fibres hybridization design, with which the electrochemical corrosion resistance and mechanical properties of UHPFRC can be well optimized. At last, X-ray CT is further employed to quantitatively understand the fibres 3D network structure of the developed UHPFRC.

这项研究解决了混合纤维3D网络对超高性能纤维增强复合材料（UHPFRC）电化学特性的内在影响，包括实验研究和机理分析。首先，基于修正的Andreasen＆Andersen模型制造UHPFRC矩阵。然后，将三种类型的纤维（长钢纤维（LSF），短钢纤维（SSF）和聚乙烯醇纤维（PVA））进一步整合到已开发的UHPFRC中，以生成不同的混合纤维3D网络。然后，分析了所设计的杂化纤维超高纯混凝土的力学性能，氯化物渗透性和电化学性能。获得的结果表明，随着PVA含量的增加，钢纤维网络会受到严重干扰，设计的UHPFRC的容量几乎呈线性下降。相反，添加的SSF导致具有混合动力的UHPFRC的容量先减小然后增大。这意味着在纤维杂交设计中有一个平衡点，利用它可以很好地优化UHPFRC的耐电化学腐蚀性能和机械性能。最后，进一步使用X射线CT来定量地了解已开发的UHPFRC的光纤3D网络结构。