Transient plane source measurements of the thermal properties of hydrating cement pastes
Transient plane source measurements of the thermal properties of hydrating cement pastes
复制标题
DOI：
10.1617/s11527-006-9206-9
复制
发表时间：
2007-12-01
影响因子：
3.8
通讯作者：
Bentz, D. P.
中科院分区：
文献类型：
--
作者：
Bentz, D. P.
瞬态平面源测量技术用于评估水化水泥浆在新鲜状态和在20℃下水化28 d过程中的热容量和导热系数。研究的变量包括水灰质量比（w/c - 0.3或0.4）和养护条件（密封或饱和养护）。将新鲜水泥浆体的热容数据与简单的混合定律进行了比较，并开发了两种养护条件下的热容作为水化程度的函数的解析表达式。通过hhashin - shtrikman （H-S）界限的应用，利用新鲜膏体的测量热导率和已知的水的热导率来估计原始水泥粉的热导率。可见水化作用对所测的导热系数只有很小的影响。讨论了热容混合定律和热导率H-S界的推广，以预测混凝土的相应性能。
A transient plane source measurement technique is applied to assessing the heat capacity and thermal conductivity of hydrating cement pastes in their fresh state and during the course of 28 d of hydration at 20 degrees C. Variables investigated include water-to-cement mass ratio (w/c - 0.3 or 0.4) and curing conditions (sealed or saturated curing). The heat capacity data for the fresh cement pastes are compared to a simple law of mixtures, and analytical expressions are developed to estimate the heat capacity as a function of degree of hydration for the two curing conditions. The measured thermal conductivities of the fresh pastes along with the known thermal conductivity of water are used to estimate the thermal conductivity of the original cement powder via application of the Hashin-Shtrikman (H-S) bounds. Hydration is seen to have only a minor influence on the measured thermal conductivity. Extension of the law of mixtures for heat capacity and the H-S bounds for thermal conductivity to predicting the corresponding properties of concretes are discussed.