Effect of initial water-curing period and curing condition on the properties of self-compacting concrete

The effect of initial water-curing period and curing condition on properties of self-compacting concrete (SCC) was studied. Six different curing regimes were applied to the specimens, the first of which the sample was stored under initial water-curing periods of 3, 7, 14 days, in the remaining three regimes, the samples were continuous full water (FW) curing condition, continuous full standard (FS) curing condition and continuous full room (FR) curing condition. The mechanical properties of SCC under different initial water-curing period and curing condition were tested, the relationship between compressive strength of concrete and curing time was analyzed by linear regression, the strength-gaining rates of SCC were calculated by using this regression equation, the durability properties of SCC, i.e. the carbonation depth, the chloride ion diffusion coefficient of SCC, were also evaluated, the relationship between 28-days compressive strength and 28-days carbonation depths of SCC under different initial water-curing period and curing condition was studied. The test results showed that it is necessary to apply water-curing to SCC for the initial 7 days period to expose the pozzolanic activity, SCC under FR curing condition has a higher compressive strength, flexural strength, a lower carbonation depth and chloride ion diffusion coefficient than SCC under FS, FW curing condition.

► The initial water-curing period and curing condition effect on the properties of SCC. ► The initial water-curing for 7 days is necessary for SCC. ► SCC under FR curing condition has higher mechanical and better durability properties. ► 28-days strength and 28-days carbonation depth of SCC has a high correlation.