Nanomechanical properties of cementitious materials
Nanomechanical properties of cementitious materials
复制标题
DOI：
10.21985/n29m9x
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
P. Mondal
中科院分区：
文献类型：
--
作者：
P. Mondal
胶凝材料的纳米力学性能虽然胶凝建筑材料主要是大规模和大量使用的，但诸如强度、延展性、蠕变、收缩和断裂行为等基本性能在很大程度上取决于在微观和纳米尺度上有效的结构元素和现象。这项研究包括使用各种成像技术表征胶凝材料的微米和纳米级性能，以及评估局部机械性能。利用原子力显微镜和一种新的纳米压痕技术研究了水泥浆体的微观结构和纳米结构。深入研究了养护龄期、水灰比、微纳改性剂对混凝土纳米力学性能的影响。此外，本研究还对混凝土界面过渡区(ITZ)的纳米力学特性进行了实验研究。尽管与ITZ的复杂性质相关的困难，这篇论文报道了第一个，最全面的努力，成功地测量其局部纳米机械性能。此外，还考察了硅灰和纳米二氧化硅添加剂对块体浆料的影响。本研究的最终目的是控制材料的宏观性能，开发性能更好的新材料。这项工作的发现将有助于更好地理解复杂的宏观现象，并为多尺度建模提供输入。
Nanomechanical Properties of Cementitious Materials Paramita Mondal Although cementitious construction materials are mainly used in a large scale and in huge quantities, fundamental properties such as strength, ductility, creep, shrinkage, and fracture behavior depend, to a great extent, on structural elements and phenomena which are effective at the microand nanoscale. This research involves characterization of the microand nanoscale properties of cementitious materials using various imaging techniques and evaluation of local mechanical properties. A systematic sample preparation technique developed in this work enabled the investigation of the microstructure and nanostructure of cement paste using atomic force microscopy and a novel nanoindentation technique. An in-depth study on the effects of curing age, water to cement ratio, and microand nano-modifiers on the nanomechanical properties of concrete was performed. Furthermore, this study examined experimentally the nanomechanical properties of the interfacial transition zone (ITZ) in concrete. Despite the difficulties associated with the complex nature of the ITZ, this dissertation reports one of the first, most comprehensive endeavors to successfully measure its local nanomechanical properties. Additionally, the effects of silica fume and nanosilica additives on bulk paste were investigated. The ultimate goal of this research is to control the macroscopic properties and develop new materials with improved properties. Findings from this work will lead to a better understanding of the complex macroscopic phenomena and also provide input for multiscale modeling.