REPRODUCTION OF DELAYED ETTRINGITE FORMATION IN CONCRETE AND ITS MECHANISM
The influence of constituents of concrete including a sulfate addition, on the expansion ofconcrete by delayed ettringite formation (DEF) is investigated in order to clarify, the DEFmechanism. Six types of mortar were prepared, with high early strength Portland cement, withwhite Portland cement which expands by more than 2.0％, with ordinary Portland cementwhich expands by 0.6％, and with moderate heat Portland cement, fly ash blended cementclass B and blast furnace slag cement class B which do not expand. The influence of the kindof aggregate is remarkable. Mortar made with quartz aggregate and ASR reactive aggregatealso exhibit great expansion during the first few days. The influence of limestone aggregateon expansion however is small compared to DEF. There exists a correlation between the freesulfate ion eluted from hardened concrete and the expansion volume of its mortar. A methodfor measuring these ions is useful in prediction of DEF.
Shunsuke Hanehara Tetsuya Oyamada Tadashi Fujiwara
Iwate University,Morioka,Japan
国际会议
南京
英文
143-152
2008-10-13（万方平台首次上网日期，不代表论文的发表时间）