Research on non-steady-state chloride ion permeability characteristics of self-compacting concrete
Chloride penetration poses a major challenge to the long-term durability of concrete structures because it may corrode steel bars and deteriorate the internal structure of concrete.Silica fume and fly ash were used as mineral admixtures to prepare self-compacting concrete.The effects of electrification time and mineral admixtures on the chloride ion permeability coefficient and mechanical properties of self-compacting concrete were studied.The results show that the chloride ion permeability coefficient increases first and then decreases with the increase of electrification time from 12 h to 36 h,indicating that there is a healing and sealing mechanism in concrete,which enhances the ability to resist chloride ion penetration.After adding silica fume and fly ash,the chloride ion permeability coefficient decreased significantly.When the content of silica fume and fly ash was 15％and 30％,the coefficient decreased to 59.9％and 49.5％,respectively.Compared with the control group,the coefficient levels decreased by 39.49％and 46.87％after 24 h and 36 h,respectively.In addition,the extension of energization time and mineral admixtures improve the splitting tensile strength of self-compacting concrete.
self-compacting concretechloride ion penetrationsilica fumefly ash
万方数据
维普
