Lee Dong Kyu, Choi Myoung Sung
Department of Safety Engineering, College of Engineering, Dongguk University-Gyeongju, 123 Dongdae-ro, Gyeongju 38066, Korea.
Materials (Basel). 2018 Oct 16;11(10):2001. doi: 10.3390/ma11102001.
For the general quantitative evaluation of the flow characteristics of a material, various factors that affect the flow should be examined. Notably, cement paste shows multi-dimensional flow characteristics owing to not only its inherent features such as its various particle sizes and hydration reaction, but also due to environmental factors including temperature, humidity, and pressure. Therefore, an analysis of those environmental factors is important for the quantitative evaluation of the flow characteristics of cement paste. In this study, we analyzed the flow characteristics of cement paste and a newly developed standard reference material (SRM) that has similar flow characteristics to cement paste at different temperatures. For the analysis, the flow characteristics of each cement paste mixture at five different temperatures (5 °C, 10 °C, 20 °C, 30 °C, and 40 °C) were examined, in consideration of variations in construction environments. Then, the flow characteristics of the developed SRM at different temperatures were also analyzed. The result of the analysis demonstrated a decrease in the rheology constant value following a rise in the temperature. Notably, the degree of variation in the flow characteristics was larger at a lower temperature, while flow characteristics remained nearly constant at higher temperatures. The result of the analysis also confirmed that cement paste and the newly developed SRM displayed similar tendencies for the change in flow characteristics following a change in temperature. In conclusion, the newly developed SRM is thought to be useful for consistently representing the flow characteristics of cement paste under various construction environments in consideration of temperature change.
为了对材料的流动特性进行一般定量评估，应研究影响流动的各种因素。值得注意的是，水泥浆体呈现多维流动特性，这不仅归因于其固有特性，如各种粒径和水化反应，还归因于包括温度、湿度和压力在内的环境因素。因此，分析这些环境因素对于定量评估水泥浆体的流动特性很重要。在本研究中，我们分析了水泥浆体以及一种新开发的标准参考材料（SRM）在不同温度下的流动特性，该标准参考材料具有与水泥浆体相似的流动特性。为了进行分析，考虑到施工环境的变化，研究了五种不同温度（5℃、10℃、20℃、30℃和40℃）下各水泥浆混合物的流动特性。然后，还分析了所开发的标准参考材料在不同温度下的流动特性。分析结果表明，流变常数随温度升高而降低。值得注意的是，在较低温度下流动特性的变化程度较大，而在较高温度下流动特性几乎保持不变。分析结果还证实，水泥浆体和新开发的标准参考材料在温度变化后流动特性的变化趋势相似。总之，考虑到温度变化，新开发的标准参考材料被认为有助于在各种施工环境下始终如一地体现水泥浆体的流动特性。
