Steam-curing Temperature Effect and Its Influence on Heat Damage of Cement-based Material
MA Kunlin, HE Jionghuang, LONG Guangcheng, DANG Hanfei, XIE Youjun
School of Civil Engineering, Central South University, National Engineering Laboratory for Construction Technology of High Speed Railway, Changsha 410075
Abstract: The temperature change of cement-based material in moist-curing and steam-curing were measured by temperature sensors. The evolutions of hydration products and microstructure were investigated by means of XRD, SEM, TGA and MIP. Results show that in the steam-curing process, temperature of specimen surface increases first. At the end of temperature increasing, surface temperature is about 30 ℃ higher than the internal temperature. Afterwards, the internal temperature increasing exceeds the surface. Internal temperature is about 25 ℃ higher than surface after constant temperature(60 ℃) curing for 3 hours. The change of temperature and time exerts limited effects on the formation of hydration products, but it brings about remarkable influence on pore structure and microtopography on surface layer. At the end of steam-curing, the total porosity and harmful pore ratio with diameter larger than 200 nm in surface layer are 1.22 and 10.3 times of that of internal structure. The total porosity is reduced effectively in moist-curing at 28 d. However, the pore ratio with diameter greater than 200 nm is still 1.6 times of moist-curing specimens.
马昆林, 贺炯煌, 龙广成, 党晗菲, 谢友均. 蒸养温度效应及其对水泥基材料热伤损的影响*[J]. 《材料导报》期刊社, 2017, 31(23): 171-176.
MA Kunlin, HE Jionghuang, LONG Guangcheng, DANG Hanfei, XIE Youjun. Steam-curing Temperature Effect and Its Influence on Heat Damage of Cement-based Material. Materials Reports, 2017, 31(23): 171-176.
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