| Title |
An Experimental Study on the Estimation of Compressive Strength of Ultra-High Strength Concrete Using Warm Water Curing Method |
| Authors |
Lee Jong-Seok ; Myung Ro-Oun ; Gong Min-Ho ; Paik Min-Su ; Lee Young-Do ; Jung Sang-Jin |
| Keywords |
Ultra High Strength Concrete ; Warm Water Curing ; Acceleration Curing ; Strength Control |
| Abstract |
In this study, prediction of later-age compressive strength of ultra-high strength concrete, based on the accelerated strength of concrete cured in hot water was investigated. Comparing other acceleration method, hot water curing method is relatively easy and intuitive to use in the real construction site. The amount of time for evaluation of the concrete strength using the hot water curing method in KS and JIS is too long to predict the strength of the ultra-high strength concrete that are used in the tall building structure. For that reason, curing temperature of 40, 50, 60℃ 3 levels were examined to shorten the amount of time for the evaluation of the strength. When curing in warm water, different strength characteristics are verified from the experiment. In case of F3 substituting 30% fly ash in combination, because of the curing temperature sensitivity of fly ash, differences of strength expression velocity was verified according to the curing temperature at the same age. In case of B4 substituting 40% ground granulated blast furnace slag, there were no big strength expression velocity differences of the specimen cured in 3 different level of curing temperature(40, 50, 60℃). The results show reliable accuracy by regression relation between 28day strength cured by standard curing method and accelerated strength of concrete cured in warm water.(y=1x-0.0002 R2=0.9866). As a result, the feasibility of 3day-prediction was confirmed using warm water curing method with accelerated strength of concrete cured for three days in warm water. |