Abrasion resistance of milling steel fiber-reinforced ultra-high-performance concrete under various wearing conditions

Ultrahigh-performance concrete (UHPC) is susceptible to various forms of abrasion during its service life. This study is an investigation of the abrasion resistance of UHPC, focusing on two primary causes of wear: dynamic traffic loads and hydraulic impacts. To enhance the material's resistance to abrasion, milling steel fibres were utilised. For comparative purposes, straight steel fibres and hybrid milling–straight steel fibres were also employed. The protective function of the steel fibres primarily comes into effect once the concrete cover has experienced wear. When subjected to traffic and hydraulic loads, UHPC containing milling fibres exhibited superior resistance, compared with that containing straight fibres, while maintaining favourable workability. Notably, the UHPC incorporating hybrid steel fibres, which form a composite skeleton, owing to the presence of two fibre types, demonstrated even greater effectiveness in resisting external abrasion. Furthermore, the abrasion resistances observed under both traffic and hydraulic conditions displayed a positive linear correlation, with R 2 > 0.8. These findings suggest the feasibility of evaluating the material's abrasion resistance under various wearing causes using a single test method. The outcomes of this study hold promise in advancing the development of UHPC and promoting its utilisation in conditions characterised by severe abrasion.