Investigation of early drying shrinkage of ultrahigh-performance concrete under windy conditions

Environmental factors (e.g., wind) may deteriorate the volume stability of ultrahigh-performance concrete (UHPC), which undermines structural safety. Therefore, in this study, the effects of wind speeds (WSs) on the early shrinkage (e.g., autogenous/drying shrinkage) of UHPC were investi-gated, and the shrinkage behaviors were further explained from the evaporation and pore structure distributions of UHPC. The results highlighted the effects of silica fume (SF) on the early shrinkage of UHPC under windy conditions, however, water evaporation should be combined with pore size distributions to obtain critical pores of UHPC. At the same time, based on the critical pore diameter, different early drying shrinkage developments were observed in UHPC under normal drying conditions and at a WS of 0.25 m/s. Further, in some cases, drying shrinkage may play a more important role that governs the early total shrinkage of UHPC than autogenous shrinkage, which complements current theories of shrinkage.