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介绍了一种新的水泥水化产物的固相-液相-凝胶体系模型。之前描述水泥水化产物的固相-液相-凝胶体系主要考虑不同环境下特别是在干燥和寒冷环境下毛细孔水和固相-凝胶结构的不同。该新模型验证了Feldman-Sereda质量变化和收缩模型以及表面能与水化形变慕尼黑模型。但是,该模型的解释与之前的模型完全不同,因为该模型考虑了凝胶颗粒在硬化水泥体系中的膨胀。该差异可以用表面物理的理论来解释。研究结果是基于小的硬化水泥石试样上进行的高精度重力吸附测量,同时结合氦流比重计测定的密度、溶解热、以及等温长度变化(收缩)等实验。试验显示,如果基于给定的相对湿度条件下的质量变化,以及表面相互作用能,而不是基于相对湿度,各实验所得结果有较为密切的关系。质量变化与在不同的水蒸气分压区间存在的毛细孔水分的类型有关。根据不同的凝胶固相与毛细孔水分的相互作用可以分为两个不同的区域:其一为凝结区,主要为凝结的凝胶内毛细孔水。该水主要由表面的相互作用所控制,其密度根据水泥种类不同大概为1.15g/cm~3至1.25g/cm~3。这种水的溶解热比体相水低大约30%,它的损失是表面作用而引起的收缩。根据质量(固体+留存的吸附水)定义该区域的边界,该质量达到了明确定义的在从潮湿或密闭养护的新生态第一次脱附期间相对湿度为22%的能量级别。
A new model of solid-liquid-gel system for cement hydration products is introduced. The solid-liquid-gel system previously described for cement hydration products mainly considers differences in capillary water and solid-gel structures in different environments, especially in dry and cold environments. The new model validates the Feldman-Sereda mass change and shrinkage model as well as the surface energy and hydration deformation Munichian model. However, the interpretation of this model is completely different from the previous model because it takes into account the swelling of the gel particles in the hardened cement system. This difference can be explained by the theory of surface physics. The results are based on high-precision gravimetric adsorption measurements carried out on small, hardened cement stone samples, combined with experiments of density, heat of solution, and isothermal length changes (shrinkage) as determined by a helium flow pycnometer. Experiments have shown that the results obtained from the experiments are more closely related to the change in mass based on the given relative humidity, as well as the surface energy, rather than the relative humidity. The mass change is related to the type of capillary moisture present at different water vapor partial pressure intervals. According to different gel solid phase and capillary pore water interaction can be divided into two different areas: one is the condensation area, mainly condensed gel capillary water. The water is mainly controlled by surface interactions and its density varies from about 1.15 g / cm3 to 1.25 g / cm3 depending on the type of cement. The water heat of dissolution is about 30% lower than the bulk water, and its loss is caused by surface effects. The boundaries of this area are defined on the basis of mass (solids + retained adsorbed water) and the mass reaches a well-defined energy level of 22% relative humidity during the first desorption from wet or closed-up protected new ecosystems.