前两天收到在UIUC时候的导师的电子邮件，说是我2000年在UIUC完成的毕业论文，终于发表在ACI Materials Journal上了。虽然现在已经不再干这一行了，听到这个消息还是蛮开心的。特此该文章收录在BLOG里，纪念一下。
||Effects of Air Entrainment on Rheology
||Leslie J. Struble and Qingye Jiang
||ACI Materials Journal
||air content; air entrainment; concrete; paste; rheology; viscosity; yield
||November 1, 2004
The effects of air entrainment on rheological parameters were studied using cement paste. The addition of air-entraining agent increased the air content up to a saturation level, above which no further increase in air content was observed. With increasing air content, the yield stress increased and the plastic viscosity decreased. The increase in yield stress was an unexpected result because increasing air is well known to cause an increase in slump, and yield stress and slump are known to be negatively correlated (as yield stress increases, slump decreases). Two competing effects are proposed to explain the effects of entrained air bubbles on rheological parameters: the attraction of cement particles and bubbles to form bubble bridges, and a fluid response of air bubbles due to their deformability. Bubble bridges are proposed to dominate in the yield stress and the fluid response is proposed to dominate when the sample is flowing.